IL4

UniProt ID: P05112
Organism: Homo sapiens
Review Status: COMPLETE
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Gene Description

Interleukin-4 (IL-4) is a secreted four-helix bundle cytokine of the IL-4/IL-13 family, produced primarily by Th2 cells, basophils, mast cells, eosinophils, and group 2 innate lymphoid cells (ILC2s). It functions as the master regulator of type 2 immunity by binding the IL-4 receptor alpha chain (IL4RA) and signaling through two receptor complexes: the type I complex (IL4RA/IL2RG) on hematopoietic cells, and the type II complex (IL4RA/IL13RA1) on non-hematopoietic and some hematopoietic cells. IL-4 signals canonically through JAK1/JAK3-STAT6, leading to GATA3 induction that drives Th2 differentiation, B cell class switch recombination to IgE and IgG4, MHC class II upregulation on B cells, and M2 macrophage polarization. IL-4 also activates IRS-2/PI3K pathways contributing to cell survival and proliferation. It is a central mediator of allergic inflammation, anti-helminth defense, and various immune regulatory processes. The protein has three disulfide bonds (Cys3-Cys127, Cys24-Cys65, Cys46-Cys99) and one N-glycosylation site (Asn62). An alternatively spliced isoform (IL-4delta2) lacking exon 2 acts as a natural antagonist.

Existing Annotations Review

GO Term Evidence Action Reason
GO:0035771 interleukin-4-mediated signaling pathway
IBA
GO_REF:0000033
ACCEPT
Summary: IL-4 is the defining ligand of the IL-4-mediated signaling pathway. It binds IL4RA to initiate JAK/STAT6 signaling cascades that drive Th2 differentiation, IgE class switching, and other downstream effects. This is a core biological process for IL-4.
Reason: This is the most specific and appropriate BP term for IL-4 as the initiating ligand of this pathway. The IBA annotation is phylogenetically well-supported and represents the central biological role of the protein. Extensively documented in the deep research and UniProt function annotation.
Supporting Evidence:
file:human/IL4/IL4-deep-research-falcon.md
IL-4 signals via two receptor complexes...type I (IL-4R-alpha/gamma-c) largely on hematopoietic cells and type II (IL-4R-alpha/IL-13R-alpha1) on many non-hematopoietic cells. JAK-STAT is canonical...converging on STAT6
PMID:12574355
IL-4-dependent AID induction was inhibited by a dominant-negative STAT6, indicating that IL-4 induced AID expression via the Janus kinase (JAK)/STAT6 signaling pathway
GO:0045893 positive regulation of DNA-templated transcription
IBA
GO_REF:0000033
ACCEPT
Summary: IL-4 signaling via STAT6 activates transcription of numerous target genes including GATA3, germline Ig epsilon transcripts, CD23, and MHC class II genes. This is a well-established downstream consequence of IL-4 signaling.
Reason: IL-4 is well-documented as a transcriptional activator through STAT6-mediated signaling. The IBA annotation is broadly correct and represents a core downstream activity. This is a general term but appropriate for a cytokine with pleiotropic transcriptional effects.
Supporting Evidence:
PMID:12574355
IL-4 was able to induce AID expression in human primary B cells and B cell lines, and IL-4-induced AID expression was further enhanced by CD40 signaling
PMID:20554961
IL-4 promotes Th2 development by inducing the expression of the GATA3 transcription factor
GO:0050776 regulation of immune response
IBA
GO_REF:0000033
ACCEPT
Summary: IL-4 is a major immunoregulatory cytokine that shapes adaptive immune responses by driving Th2 polarization, B cell activation and class switching, and M2 macrophage polarization, while simultaneously suppressing Th1 responses.
Reason: This is a broad but accurate term for IL-4. As a key immunoregulatory cytokine, IL-4 fundamentally regulates immune responses. The IBA annotation is well-supported. While more specific terms exist and are also annotated, this general term appropriately captures the broad immunoregulatory role.
Supporting Evidence:
file:human/IL4/IL4-deep-research-falcon.md
IL-4 is a central driver of type-2 endotypes (eosinophilic/allergic) across airway and barrier diseases
GO:0050728 negative regulation of inflammatory response
IBA
GO_REF:0000033
ACCEPT
Summary: IL-4 has well-documented anti-inflammatory properties, particularly in suppressing pro-inflammatory Th1/M1 macrophage responses, inhibiting TNF-alpha production, and promoting M2 (anti-inflammatory) macrophage polarization. This is a core function of IL-4 in immune regulation.
Reason: IL-4 is a canonical anti-inflammatory cytokine that promotes M2 macrophage polarization and suppresses pro-inflammatory cytokine production. The IBA annotation is phylogenetically well-supported and consistent with extensive experimental evidence.
Supporting Evidence:
file:human/IL4/IL4-deep-research-falcon.md
IL-4 drives...alternative (M2) macrophage activation
GO:0005125 cytokine activity
IEA
GO_REF:0000043
ACCEPT
Summary: IL-4 is by definition a cytokine - a secreted signaling molecule that modulates immune cell behavior. This is the most fundamental molecular function classification for IL-4.
Reason: IL-4 is unambiguously a cytokine. The IEA annotation from UniProt keyword mapping is correct and consistent with the IDA annotation for the same term. This broad MF term is appropriate alongside the more specific GO:0005136 (interleukin-4 receptor binding).
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
Cytokine secreted primarily by mast cells, T-cells, eosinophils, and basophils that plays a role in regulating antibody production, hematopoiesis and inflammation
GO:0005126 cytokine receptor binding
IEA
GO_REF:0000002
ACCEPT
Summary: IL-4 binds cytokine receptors (IL4RA, IL13RA1) as part of its signaling mechanism. This is a parent term of the more specific GO:0005136 (interleukin-4 receptor binding).
Reason: This is a correct but less specific parent term. Since the more specific GO:0005136 is also annotated, this IEA annotation is redundant but not incorrect. Acceptable as an IEA capturing the broader category.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
Upon binding to IL4, IL4R receptor dimerizes either with the common IL2R gamma chain/IL2RG...or with the IL13RA1
GO:0005136 interleukin-4 receptor binding
IEA
GO_REF:0000002
ACCEPT
Summary: IL-4 specifically binds the IL-4 receptor alpha chain (IL4RA) at its site I interface (helices A-C, key residues Glu9/Arg88). This is the most specific and informative MF term for IL-4.
Reason: This is the core molecular function of IL-4 as a ligand. The IEA annotation from InterPro domain mapping is correct and supported by extensive structural and biochemical data, including crystal structures of the IL-4/IL4RA complex.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
Interacts with IL4R...Interacts with IL13RA1
file:human/IL4/IL4-deep-research-falcon.md
structure-function mapping identifies site I on helices A-C as the IL-4R-alpha interface (key residues Glu9, Arg88)
GO:0005576 extracellular region
IEA
GO_REF:0000120
ACCEPT
Summary: IL-4 is a secreted cytokine that functions in the extracellular region. UniProt annotates it as Secreted.
Reason: IL-4 is a secreted protein with a signal peptide (residues 1-24). The extracellular region localization is correct and well-established. This is broader than GO:0005615 (extracellular space) but acceptable as an IEA annotation.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
SUBCELLULAR LOCATION: Secreted
GO:0005615 extracellular space
IEA
GO_REF:0000043
ACCEPT
Summary: IL-4 is secreted into the extracellular space where it functions as a paracrine/ autocrine signaling molecule.
Reason: Correct IEA annotation consistent with the IDA evidence for the same term. IL-4 is a secreted cytokine that acts in the extracellular space.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
SUBCELLULAR LOCATION: Secreted
GO:0006955 immune response
IEA
GO_REF:0000002
ACCEPT
Summary: IL-4 is a key mediator of immune responses, particularly type 2 immunity. This is a very broad BP term.
Reason: This is a very general but correct IEA annotation. IL-4 is fundamentally an immune response mediator. More specific terms are also annotated. Acceptable as a broad IEA classification.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
Cytokine secreted primarily by mast cells, T-cells, eosinophils, and basophils that plays a role in regulating antibody production, hematopoiesis and inflammation, and the development of effector T-cell responses
GO:0008083 growth factor activity
IEA
GO_REF:0000120
KEEP AS NON CORE
Summary: IL-4 was historically known as B-cell stimulatory factor 1 (BSF-1) and promotes proliferation of B and T cells. However, its primary identity is as a cytokine rather than a classical growth factor.
Reason: While IL-4 does promote cell proliferation (B cells, T cells), its primary molecular function is better described as cytokine activity (GO:0005125) and IL-4 receptor binding (GO:0005136). Growth factor activity is a secondary characterization. The UniProt keyword mapping that generated this annotation reflects the historical BSF-1 naming but is not the most informative descriptor.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
AltName...B-cell stimulatory factor 1; Short=BSF-1
GO:0010628 positive regulation of gene expression
IEA
GO_REF:0000117
ACCEPT
Summary: IL-4 upregulates expression of numerous genes through STAT6 signaling, including GATA3, AID, germline Ig epsilon transcripts, CD23, and MHC class II molecules.
Reason: This is a broad but correct IEA annotation from ARBA. IL-4 is a potent inducer of gene expression in immune cells. More specific transcription regulation terms are also annotated.
Supporting Evidence:
PMID:12574355
IL-4 was able to induce AID expression in human primary B cells and B cell lines
GO:0030335 positive regulation of cell migration
IEA
GO_REF:0000117
KEEP AS NON CORE
Summary: IL-4 can promote cell migration in certain contexts, including macrophage and tumor cell migration. This is a secondary, context-dependent effect.
Reason: While there is evidence that IL-4 can regulate cell migration, this is not a core function of the cytokine. It represents a pleiotropic downstream effect rather than the primary evolved function. The ARBA-generated IEA annotation is acceptable but should not be considered a defining function.
GO:0042113 B cell activation
IEA
GO_REF:0000043
ACCEPT
Summary: IL-4 is a major B cell activating factor that induces B cell proliferation, class switching to IgE and IgG, and upregulation of MHC class II and CD23. This is one of the historically defining functions of IL-4 (originally named B-cell stimulatory factor 1).
Reason: B cell activation is a core function of IL-4. The IEA from UniProt keyword mapping accurately reflects that IL-4 was originally identified as BSF-1 precisely because of its B cell activating properties.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
Induces the expression of class II MHC molecules on resting B-cells. Enhances both secretion and cell surface expression of IgE and IgG1
GO:0045321 leukocyte activation
IEA
GO_REF:0000117
ACCEPT
Summary: IL-4 activates multiple leukocyte types including B cells, T cells, macrophages, and dendritic cells. This is a broad parent term.
Reason: This broad IEA term is correct. IL-4 activates multiple leukocyte populations. More specific child terms (B cell activation, T cell activation, macrophage activation) are also annotated.
GO:0051239 regulation of multicellular organismal process
IEA
GO_REF:0000117
MARK AS OVER ANNOTATED
Summary: IL-4 regulates immune processes at the organismal level, affecting allergic responses, anti-helminth immunity, and tissue remodeling.
Reason: This is an extremely broad and uninformative term. While technically true, it provides no useful information about IL-4 function. More specific terms are available and annotated. The ARBA machine learning annotation is too general to be informative.
GO:0080090 regulation of primary metabolic process
IEA
GO_REF:0000117
MARK AS OVER ANNOTATED
Summary: IL-4 can regulate metabolic processes in target cells, but this is an extremely broad and uninformative annotation.
Reason: This term is far too general to be informative for IL-4 annotation. While IL-4 signaling does affect metabolic processes in target cells, this ARBA-generated term does not convey any meaningful biological insight about the protein.
GO:0005515 protein binding
IPI
PMID:10219247
Crystal structure of the interleukin-4/receptor alpha chain ...
MODIFY
Summary: PMID:10219247 reports the crystal structure of IL-4 in complex with IL4RA at 2.30 angstroms resolution, demonstrating direct protein-protein interaction. The WITH column specifies UniProtKB:P24394 (IL4R).
Reason: The protein binding annotation is uninformative. The interaction demonstrated in PMID:10219247 is specifically IL-4 binding to the IL-4 receptor alpha chain, which is better captured by GO:0005136 (interleukin-4 receptor binding), which is already annotated via IEA, TAS, and IDA evidence.
Proposed replacements: interleukin-4 receptor binding
Supporting Evidence:
PMID:10219247
IL-4 binds with high affinity and specificity to the ectodomain of the IL-4 receptor alpha chain (IL4-BP)
file:human/IL4/IL4-uniprot.txt
X-RAY CRYSTALLOGRAPHY (2.30 ANGSTROMS) OF 25-153 IN COMPLEX WITH IL4R...INTERACTION WITH IL4R
GO:0005515 protein binding
IPI
PMID:18243101
Molecular and structural basis of cytokine receptor pleiotro...
MODIFY
Summary: PMID:18243101 reports the crystal structure of IL-4 in complex with IL13RA1 and IL4RA, elucidating the molecular basis of cytokine receptor pleiotropy in the IL-4/IL-13 system. The GOA TSV shows two separate annotations from this PMID, one with IL4R (P24394) and one with IL13RA1 (P78552).
Reason: The generic protein binding term is uninformative. The interaction with IL4RA is better captured by GO:0005136, and the interaction with IL13RA1 represents a component of the type II receptor complex formation.
Proposed replacements: interleukin-4 receptor binding
Supporting Evidence:
PMID:18243101
Here we present the crystal structures of the complete set of type I (IL-4R alpha/gamma(c)/IL-4) and type II (IL-4R alpha/IL-13R alpha1/IL-4, IL-4R alpha/IL-13R alpha1/IL-13) ternary signaling complexes
file:human/IL4/IL4-uniprot.txt
X-RAY CRYSTALLOGRAPHY (2.93 ANGSTROMS) OF 25-153...INTERACTION WITH IL13RA1, AND FUNCTION
GO:0005515 protein binding
IPI
PMID:23597562
Inhibition of tumor angiogenesis and growth by a small-molec...
MODIFY
Summary: PMID:23597562 is about a small-molecule FGFR inhibitor (SSR128129E) and its anti-tumor angiogenesis effects. The WITH column specifies IL4R (P24394). This annotation likely derives from an IntAct high-throughput dataset associated with this publication where IL4-IL4R interaction was detected.
Reason: The IL-4/IL-4R interaction is well-established but the generic protein binding term is uninformative. If the interaction is genuine, it is better captured by GO:0005136 (interleukin-4 receptor binding). Additionally, the primary publication focus is FGFR biology, making the provenance of this specific annotation unclear.
Proposed replacements: interleukin-4 receptor binding
Supporting Evidence:
PMID:23597562
we report the pharmacologic characterization of the chemical SSR128129E (SSR), which inhibits fibroblast growth factor receptor (FGFR) signaling
GO:0005515 protein binding
IPI
PMID:8266078
Interleukin-2 receptor gamma chain: a functional component o...
MODIFY
Summary: PMID:8266078 demonstrates that the IL-2 receptor gamma chain is a functional component of the IL-4 receptor, showing IL-4 binding and signaling through the IL4RA/IL2RG complex.
Reason: As with the other protein binding annotations for IL-4, the interaction with IL4R is better captured by the specific term GO:0005136 (interleukin-4 receptor binding). The generic protein binding term is uninformative.
Proposed replacements: interleukin-4 receptor binding
Supporting Evidence:
PMID:8266078
IL-2R gamma was demonstrated to be a component of the IL-4 receptor on the basis of chemical cross-linking data, the ability of IL-2R gamma to augment IL-4 binding affinity, and the requirement for IL-2R gamma in IL-4-mediated phosphorylation of insulin receptor substrate-1
GO:0007259 cell surface receptor signaling pathway via JAK-STAT
IDA
PMID:23103943
Redirecting cell-type specific cytokine responses with engin...
ACCEPT
Summary: IL-4 signals through JAK1/JAK3 (type I receptor) and JAK1/TYK2 (type II receptor) to activate STAT6, and to a lesser extent STAT3. This annotation captures the canonical signaling mechanism.
Reason: JAK-STAT signaling is the primary intracellular signaling pathway activated by IL-4. The IDA annotation from ComplexPortal is well-supported by extensive literature.
Supporting Evidence:
PMID:23103943
Formation of the IL-4/IL-4Rα/γc or IL-4/IL-4Rα/IL-13Rα1 complex on the cell surface activates intracellular signaling pathways including the Jak-STAT and the PI3K/Akt pathways
file:human/IL4/IL4-uniprot.txt
Engagement of both types of receptors initiates JAK3 and to a lower extend JAK1 phosphorylation leading to activation of the signal transducer and activator of transcription 6/STAT6
file:human/IL4/IL4-deep-research-falcon.md
JAK-STAT is canonical...type I (primarily JAK1/JAK3) and type II (JAK2/TYK2 reported), converging on STAT6
GO:0035771 interleukin-4-mediated signaling pathway
NAS
PMID:18243101
Molecular and structural basis of cytokine receptor pleiotro...
ACCEPT
Summary: PMID:18243101 elucidated the structural basis for cytokine receptor pleiotropy in the IL-4/IL-13 system, providing mechanistic insight into IL-4 signaling through both type I and type II receptor complexes.
Reason: This NAS annotation is well-supported. The referenced paper provides definitive structural evidence for IL-4 receptor complex assembly, which is the initiating event of the IL-4-mediated signaling pathway. Duplicate of the IBA annotation but with different evidence, which is acceptable.
Supporting Evidence:
PMID:18243101
Here we present the crystal structures of the complete set of type I (IL-4R alpha/gamma(c)/IL-4) and type II (IL-4R alpha/IL-13R alpha1/IL-4, IL-4R alpha/IL-13R alpha1/IL-13) ternary signaling complexes
file:human/IL4/IL4-uniprot.txt
X-RAY CRYSTALLOGRAPHY...OF 25-153, DISULFIDE BONDS, INTERACTION WITH IL13RA1, AND FUNCTION
GO:0042531 positive regulation of tyrosine phosphorylation of STAT protein
NAS
PMID:18243101
Molecular and structural basis of cytokine receptor pleiotro...
ACCEPT
Summary: IL-4 receptor engagement leads to JAK-mediated phosphorylation of STAT6 (at Y641) and STAT3 (at Y705). This is a direct mechanistic consequence of IL-4 signaling.
Reason: STAT6 tyrosine phosphorylation is the key signaling event downstream of IL-4 receptor activation. The NAS annotation from ComplexPortal accurately captures this core signaling mechanism. The Reactome pathway also documents JAK1 phosphorylation of STAT3 and STAT6.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
Engagement of both types of receptors initiates JAK3 and to a lower extend JAK1 phosphorylation leading to activation of the signal transducer and activator of transcription 6/STAT6
PMID:12574355
IL-4-dependent AID induction was inhibited by a dominant-negative STAT6, indicating that IL-4 induced AID expression via the Janus kinase (JAK)/STAT6 signaling pathway
GO:1902107 positive regulation of leukocyte differentiation
NAS
PMID:23103943
Redirecting cell-type specific cytokine responses with engin...
ACCEPT
Summary: IL-4 drives differentiation of multiple leukocyte lineages including Th2 cells from naive T cells, dendritic cells from monocytes, and M2 macrophages from monocytes/ macrophages.
Reason: This is a well-supported annotation. IL-4 is a key driver of leukocyte differentiation programs, particularly Th2 differentiation and dendritic cell differentiation. The NAS evidence from ComplexPortal is consistent with extensive experimental data.
Supporting Evidence:
PMID:23103943
Cytokines dimerize their receptors, with the binding of the 'second chain' triggering signaling
file:human/IL4/IL4-deep-research-falcon.md
IL-4 drives Th2 differentiation (via STAT6->GATA3), B-cell proliferation and class-switch recombination to IgE, and alternative (M2) macrophage activation
GO:0007259 cell surface receptor signaling pathway via JAK-STAT
IGI
PMID:12574355
Human activation-induced cytidine deaminase is induced by IL...
ACCEPT
Summary: PMID:12574355 demonstrates that IL-4 induces AID expression via JAK/STAT6 signaling, and that CD45 negatively regulates this pathway by acting as a JAK phosphatase. The IGI annotation with STAT6 (P42226) provides genetic interaction evidence.
Reason: The paper directly demonstrates IL-4 activates JAK/STAT6 signaling using dominant- negative STAT6 experiments. The genetic interaction with STAT6 provides strong evidence for this pathway annotation.
Supporting Evidence:
PMID:12574355
IL-4-dependent AID induction was inhibited by a dominant-negative STAT6, indicating that IL-4 induced AID expression via the Janus kinase (JAK)/STAT6 signaling pathway
GO:0035771 interleukin-4-mediated signaling pathway
IDA
PMID:12574355
Human activation-induced cytidine deaminase is induced by IL...
ACCEPT
Summary: PMID:12574355 directly demonstrates IL-4 signaling through JAK/STAT6 in the context of AID gene induction in B cells.
Reason: The paper provides direct experimental evidence for IL-4-mediated signaling pathway activation using IL-4 stimulation of B cells and demonstrating JAK-dependent STAT6 activation.
Supporting Evidence:
PMID:12574355
IL-4 was able to induce AID expression in human primary B cells and B cell lines...IL-4-induced AID expression was further enhanced by CD40 signaling
GO:0045944 positive regulation of transcription by RNA polymerase II
IGI
PMID:12574355
Human activation-induced cytidine deaminase is induced by IL...
ACCEPT
Summary: PMID:12574355 shows IL-4 induces AID gene transcription through STAT6-dependent mechanisms. The IGI evidence includes interactions with CD45 (P08575), CD40 (P29965), and STAT6 (P42226).
Reason: The paper demonstrates IL-4 positively regulates transcription of the AID gene in B cells, with genetic interaction evidence from STAT6 dominant-negative, CD45, and CD40 experiments.
Supporting Evidence:
PMID:12574355
IL-4 was able to induce AID expression in human primary B cells and B cell lines, and IL-4-induced AID expression was further enhanced by CD40 signaling
GO:0005125 cytokine activity
IDA
PMID:10219247
Crystal structure of the interleukin-4/receptor alpha chain ...
ACCEPT
Summary: PMID:10219247 reports the crystal structure of the IL-4/IL4RA complex and characterizes the receptor binding interface, providing direct structural evidence for IL-4's cytokine activity.
Reason: This IDA annotation is well-supported. The referenced paper demonstrates direct IL-4/receptor interaction through structural analysis, confirming IL-4 functions as a cytokine that binds and activates its cognate receptor.
Supporting Evidence:
PMID:10219247
Interleukin-4 (IL-4) is a principal regulatory cytokine during an immune response and a crucial determinant for allergy and asthma
file:human/IL4/IL4-uniprot.txt
Crystal structure of the interleukin-4/receptor alpha chain complex reveals a mosaic binding interface
GO:0005615 extracellular space
IDA
PMID:3279117
Modulation of phenotypic and functional properties of human ...
ACCEPT
Summary: PMID:3279117 demonstrates that exogenous recombinant IL-4 acts on monocytes in culture, confirming its activity as a secreted extracellular protein. The paper shows IL-4 modulates monocyte phenotype and function when added to culture medium.
Reason: IL-4 is a secreted cytokine with a signal peptide. Its localization to the extracellular space is unambiguous. The paper demonstrates IL-4 acting as an extracellular factor on monocytes.
Supporting Evidence:
PMID:3279117
Highly purified peripheral blood monocytes were cultured in the presence of rIL-4
file:human/IL4/IL4-uniprot.txt
SUBCELLULAR LOCATION: Secreted
GO:0035771 interleukin-4-mediated signaling pathway
IDA
PMID:10219247
Crystal structure of the interleukin-4/receptor alpha chain ...
ACCEPT
Summary: PMID:10219247 provides structural evidence for IL-4 receptor complex formation, the initiating event of the IL-4-mediated signaling pathway.
Reason: The crystal structure of IL-4 bound to IL4RA demonstrates the molecular basis of IL-4 signaling initiation. This IDA annotation is well-supported and consistent with other annotations for the same GO term.
Supporting Evidence:
PMID:10219247
this intermediate complex recruits the common gamma chain (gamma c), thereby initiating transmembrane signaling
file:human/IL4/IL4-uniprot.txt
Crystal structure of the interleukin-4/receptor alpha chain complex reveals a mosaic binding interface
GO:0000122 negative regulation of transcription by RNA polymerase II
IDA
PMID:11967989
Interleukin-4 regulates connective tissue growth factor expr...
KEEP AS NON CORE
Summary: PMID:11967989 shows that IL-4 attenuates TGF-beta-stimulated induction of CTGF mRNA expression in human lung fibroblasts, through interference with TGF-beta-induced transcriptional activation of the CTGF gene.
Reason: The paper demonstrates IL-4 can negatively regulate specific gene transcription (CTGF), but this is a context-specific effect in lung fibroblasts rather than a core function of IL-4. IL-4's primary role is transcriptional activation of immune genes, not transcriptional repression.
Supporting Evidence:
PMID:11967989
IL-4 attenuated the TGF-beta-stimulated induction of CTGF mRNA expression by 50%...IL-4 interfered with the TGF-beta-induced transcriptional activation of the CTGF gene
GO:1903845 negative regulation of cellular response to transforming growth factor beta stimulus
IDA
PMID:11967989
Interleukin-4 regulates connective tissue growth factor expr...
KEEP AS NON CORE
Summary: PMID:11967989 directly demonstrates that IL-4 antagonizes TGF-beta signaling in lung fibroblasts by attenuating TGF-beta-induced CTGF expression.
Reason: While the paper provides direct evidence for this annotation, IL-4's antagonism of TGF-beta signaling in fibroblasts is a tissue-specific context-dependent effect, not a core function of the cytokine. This represents pleiotropic activity.
Supporting Evidence:
PMID:11967989
IL-4 attenuated the TGF-beta-stimulated induction of CTGF mRNA expression by 50%. This effect was selective because IL-4 did not affect fibronectin or alpha1(I) collagen mRNA expression induced by TGF-beta
GO:0008284 positive regulation of cell population proliferation
IGI
PMID:31432141
miR‑320a upregulation contributes to the development of pree...
KEEP AS NON CORE
Summary: PMID:31432141 identifies IL-4 as a direct target of miR-320a in trophoblast cells (HTR-8/SVneo). Rescue experiments demonstrate that IL-4 overexpression partially reverses the anti-proliferative effect of miR-320a on trophoblast cells (MTT assay). The IGI evidence involves miR-320a (RNAcentral:URS00003CF1AD_9606) with acts_upstream_of_or_within qualifier. The proliferation effect is in trophoblast cells in the context of preeclampsia.
Reason: The paper provides evidence that IL-4 promotes trophoblast cell proliferation in the preeclampsia context. While IL-4 also promotes B and T cell proliferation as a core function (annotated separately via ISS), this specific annotation reflects a non-immune cell proliferation effect that is not a core function of the cytokine.
Supporting Evidence:
PMID:31432141
restoring the expression level of IL-4 partially decreased the inhibitory effect of miR-320a overexpression on HTR-8/SVneo cell proliferation
PMID:31432141
Collectively, the present data suggested that IL-4 was a functional target gene of miR-320a, and miR-320a upregulation inhibited the proliferation and invasion of HTR-8/SVneo cells by directly targeting IL-4
GO:0030335 positive regulation of cell migration
IGI
PMID:31432141
miR‑320a upregulation contributes to the development of pree...
KEEP AS NON CORE
Summary: PMID:31432141 studies miR-320a in preeclampsia trophoblast cells (HTR-8/SVneo). IL-4 is identified as a direct target of miR-320a. Rescue experiments show that overexpression of IL-4 partially reverses the inhibitory effect of miR-320a on trophoblast cell invasion (Transwell assay). The IGI evidence involves miR-320a (RNAcentral:URS00003CF1AD_9606) as the interacting partner, with acts_upstream_of_or_within qualifier. The cell migration/invasion effect is in trophoblast cells, not immune cells.
Reason: The paper provides evidence that IL-4 promotes trophoblast cell invasion in the context of preeclampsia, which is consistent with the IEA annotation for the same term that was already marked KEEP_AS_NON_CORE. Cell migration promotion is not a core immune function of IL-4 but represents a pleiotropic effect in non-immune cell types.
Supporting Evidence:
PMID:31432141
overexpression of IL-4 in HTR-8/SVneo cells reduced the inhibitory effect of miR-320a overexpression on cell invasion
PMID:31432141
miR-320a upregulation inhibited the proliferation and invasion of HTR-8/SVneo cells by directly targeting IL-4
GO:0032733 positive regulation of interleukin-10 production
IGI
PMID:30634164
IL-16 regulates macrophage polarization as a target gene of ...
ACCEPT
Summary: PMID:30634164 studies macrophage polarization and shows that M2 macrophages (induced by IL-4 and IL-13) express higher levels of IL-10 than M1 macrophages. The IGI evidence involves IL-13 (P35225), reflecting the cooperative use of IL-4 and IL-13 in M2 polarization protocols.
Reason: The paper demonstrates that IL-4/IL-13-induced M2 macrophages express higher IL-10 levels than M1 macrophages, supporting IL-4's role in promoting IL-10 production. This is consistent with IL-4's well-established anti-inflammatory M2-polarizing function and the known IL-10 production by M2 macrophages.
Supporting Evidence:
PMID:30634164
M1 macrophages express higher levels of IL-16 than M2 macrophages but express lower levels of IL-10 and mir-145 than M2 cells
GO:0042116 macrophage activation
IGI
PMID:30634164
IL-16 regulates macrophage polarization as a target gene of ...
ACCEPT
Summary: PMID:30634164 uses IL-4 and IL-13 to induce M2 macrophage polarization from THP-1 monocytes. IL-4 is a canonical driver of alternative macrophage activation (M2 polarization). The IGI evidence with IL-13 (P35225) reflects the cooperative use of these cytokines in M2 polarization.
Reason: M2 macrophage activation by IL-4 is one of its best-established functions. The paper directly uses IL-4 in the M2 polarization protocol. This is extensively documented in the deep research and is a core function of IL-4 in innate immunity.
Supporting Evidence:
PMID:30634164
THP-1 cells were induced by IL-4 and IL-13 following PMA incubation (M2 polarized macrophages) or induced by IFN-gamma and LPS (M1 classical macrophage activation)
file:human/IL4/IL4-deep-research-falcon.md
IL-4 drives...alternative (M2) macrophage activation; IL-13 overlaps but acts more directly on structural cells
GO:0050728 negative regulation of inflammatory response
IGI
PMID:30634164
IL-16 regulates macrophage polarization as a target gene of ...
ACCEPT
Summary: PMID:30634164 demonstrates that IL-4/IL-13-induced M2 macrophages have an anti-inflammatory profile with high IL-10 and low pro-inflammatory cytokines. IL-4 suppresses inflammatory responses through M2 macrophage polarization. The IGI evidence with IL-13 (P35225) reflects cooperative anti-inflammatory signaling.
Reason: This is a duplicate of the IBA annotation for the same term, with independent IGI evidence. The anti-inflammatory role of IL-4 is well-established and represents a core function. Duplicate annotations with different evidence codes are acceptable.
Supporting Evidence:
PMID:30634164
THP-1 cells were induced by IL-4 and IL-13 following PMA incubation (M2 polarized macrophages) or induced by IFN-gamma and LPS (M1 classical macrophage activation)
file:human/IL4/IL4-deep-research-falcon.md
IL-4 drives...alternative (M2) macrophage activation
GO:0010628 positive regulation of gene expression
ISS
GO_REF:0000024
ACCEPT
Summary: IL-4 upregulates gene expression in target cells through STAT6-mediated transcriptional activation. Transferred from mouse IL-4 (P07750) and rat IL-4 (P20096).
Reason: This ISS annotation is well-supported by the conserved function of IL-4 across mammals. IL-4 is a potent inducer of gene expression through STAT6 signaling. The annotation is consistent with the IDA evidence for transcription regulation and with the IEA annotation for the same term.
Supporting Evidence:
PMID:12574355
IL-4 was able to induce AID expression in human primary B cells and B cell lines
GO:0150076 neuroinflammatory response
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: IL-4 has been implicated in neuroinflammation, particularly in the context of neuroprotection and microglial polarization. Transferred from mouse IL-4 (P20096) by ARUK-UCL curators.
Reason: While IL-4 has documented roles in neuroinflammation (primarily anti-inflammatory/ neuroprotective effects via M2 microglial polarization), this is a tissue-specific context-dependent activity, not a core immune function of IL-4. The ISS from mouse is reasonable but this represents a specialized function.
GO:0032720 negative regulation of tumor necrosis factor production
ISS
GO_REF:0000024
ACCEPT
Summary: IL-4 suppresses TNF-alpha production, particularly in macrophages, as part of its anti-inflammatory and M2-polarizing activity. Transferred from mouse IL-4 (P07750).
Reason: Suppression of TNF-alpha production is a well-established function of IL-4 in the context of its anti-inflammatory M2 macrophage polarization program. The ISS from mouse is appropriate given conserved IL-4 function.
Supporting Evidence:
file:human/IL4/IL4-deep-research-falcon.md
IL-4 drives...alternative (M2) macrophage activation
GO:1901857 positive regulation of cellular respiration
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: IL-4 has been reported to promote mitochondrial respiration in macrophages as part of M2 metabolic reprogramming. Transferred from mouse IL-4 (P07750) by ARUK-UCL.
Reason: While IL-4-driven M2 macrophage polarization involves metabolic reprogramming toward oxidative phosphorylation, this metabolic effect is a downstream consequence of M2 polarization rather than a core function of IL-4 itself. The annotation is not incorrect but represents a specialized downstream effect.
GO:2001171 positive regulation of ATP biosynthetic process
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: Related to the metabolic reprogramming of M2 macrophages toward oxidative phosphorylation. Transferred from mouse IL-4 (P07750) by ARUK-UCL.
Reason: This is a highly specific metabolic effect that is downstream of M2 macrophage polarization. Not a core function of IL-4 as a cytokine. Over-specific annotation of a downstream metabolic consequence.
GO:0150079 negative regulation of neuroinflammatory response
IC
GO_REF:0000111
KEEP AS NON CORE
Summary: IC annotation inferred from ISS evidence. IL-4 has anti-inflammatory effects in the CNS, promoting M2 microglial polarization and suppressing neuroinflammation.
Reason: While IL-4 has documented neuroprotective and anti-neuroinflammatory effects, these are tissue-specific activities rather than core immune functions. The IC evidence based on ISS is reasonable but this represents a specialized function.
GO:0048260 positive regulation of receptor-mediated endocytosis
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: IL-4 may promote receptor-mediated endocytosis in certain cell types, possibly related to amyloid-beta clearance by microglia. Transferred from mouse IL-4 (P07750 and P20096) by ARUK-UCL.
Reason: This annotation likely relates to IL-4's role in promoting microglial phagocytic clearance of amyloid-beta, which is a very specialized neuroimmune function rather than a core IL-4 activity.
GO:1900223 positive regulation of amyloid-beta clearance
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: IL-4 has been reported to promote amyloid-beta clearance by microglia in Alzheimer's disease models. Transferred from mouse IL-4 (P07750 and P20096) by ARUK-UCL.
Reason: While there is mouse literature supporting IL-4's role in promoting amyloid-beta clearance, this is a highly specialized neuroimmune function that is far from the core evolved function of IL-4 as an immune cytokine. The ISS transfer is reasonable but this represents a tissue-specific activity.
GO:0016239 positive regulation of macroautophagy
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: IL-4 has been reported to stimulate autophagy in dendritic cells. The UniProt function annotation notes IL-4 stimulates autophagy by interfering with mTORC1 signaling and through RUFY4 induction. Transferred from mouse IL-4 (P07750).
Reason: While UniProt documents this function, autophagy induction is a specialized downstream effect of IL-4 signaling rather than a core function. The ISS annotation is supported by the UniProt function description.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
Stimulates autophagy in dendritic cells by interfering with mTORC1 signaling and through the induction of RUFY4
GO:0120162 positive regulation of cold-induced thermogenesis
ISS
PMID:24906148
Eosinophils and type 2 cytokine signaling in macrophages orc...
KEEP AS NON CORE
Summary: PMID:24906148 demonstrates that IL-4/IL-13 signaling in macrophages is required for cold-induced beige fat biogenesis. Administration of IL-4 to thermoneutral mice increases beige fat mass and thermogenic capacity. The ISS is from mouse IL-4 (P07750).
Reason: While the paper provides compelling evidence that IL-4 promotes beige fat thermogenesis through alternatively activated macrophages, this is a specialized metabolic function far removed from IL-4's core immune role.
Supporting Evidence:
PMID:24906148
Genetic loss of eosinophils or IL-4/13 signaling impairs cold-induced biogenesis of beige fat
PMID:24906148
administration of IL-4 to thermoneutral mice increases beige fat mass and thermogenic capacity to ameliorate pre-established obesity
GO:0042110 T cell activation
IGI
PMID:18337562
CCL5-mediated T-cell chemotaxis involves the initiation of m...
UNDECIDED
Summary: PMID:18337562 is about CCL5-mediated T cell chemotaxis involving mTOR/4E-BP1 translation initiation. The paper studied CD4+ T cell migration in response to CCL5, not IL-4. The IGI evidence involves CD82 (P10747). The connection to IL-4 is unclear.
Reason: The referenced publication (PMID:18337562) is about CCL5 (RANTES)-mediated T cell chemotaxis, not IL-4 function. While IL-4 is known to activate T cells (particularly driving Th2 differentiation), this specific annotation appears to reference an unrelated paper. The annotation may have been made based on a secondary finding or data in the paper, but the primary focus is CCL5.
Supporting Evidence:
PMID:18337562
CCL5-mediated T-cell chemotaxis involves the initiation of mRNA translation through mTOR/4E-BP1
GO:0045892 negative regulation of DNA-templated transcription
IDA
PMID:16606666
B7-H4 expression identifies a novel suppressive macrophage p...
KEEP AS NON CORE
Summary: PMID:16606666 demonstrates that IL-4 inhibits B7-H4 (VTCN1) expression on tumor macrophages in human ovarian carcinoma. IL-4 negatively regulates B7-H4 transcription, in contrast to IL-6 and IL-10 which stimulate its expression.
Reason: The paper provides direct evidence that IL-4 negatively regulates B7-H4 expression on macrophages. This is consistent with the other GO:0045892 annotation from PMID:18579517 (also KEEP_AS_NON_CORE) and the GO:0000122 annotation from PMID:11967989 for CTGF. IL-4's ability to repress specific genes is a real but context-dependent activity, not a core function.
Supporting Evidence:
PMID:16606666
granulocyte/macrophage colony-stimulating factor and IL-4, which are limited in the tumor microenvironment, inhibit B7-H4 expression
GO:0005576 extracellular region
TAS
Reactome:R-HSA-6785821
ACCEPT
Summary: Reactome annotation for IL-4 participation in the IL-4/IL-13 signaling pathway, specifically the SOCS5/SOCS1 binding to IL4RA reaction. IL-4 is correctly placed in the extracellular region.
Reason: IL-4 is a secreted cytokine in the extracellular region. These Reactome TAS annotations correctly reflect IL-4's participation in signaling pathway reactions as an extracellular ligand.
GO:0005576 extracellular region
TAS
Reactome:R-HSA-6786058
ACCEPT
Summary: Reactome annotation for IL-4 signaling - JAK1 binding to IL4R in IL4-bound complex.
Reason: Duplicate CC annotation from Reactome pathway. IL-4 is correctly localized to the extracellular region as part of the receptor-ligand complex.
GO:0005576 extracellular region
TAS
Reactome:R-HSA-6786070
ACCEPT
Summary: Reactome annotation for type II receptor complex assembly (IL-4 complex binding IL13RA1/TYK2).
Reason: Duplicate CC annotation from Reactome pathway. Correct localization.
GO:0005576 extracellular region
TAS
Reactome:R-HSA-6786072
ACCEPT
Summary: Reactome annotation for STAT3/STAT6 dissociation step in IL-4 signaling.
Reason: Duplicate CC annotation from Reactome pathway. Correct localization.
GO:0005576 extracellular region
TAS
Reactome:R-HSA-6786092
ACCEPT
Summary: Reactome annotation for type I receptor complex assembly (IL-4 complex binding IL2RG/JAK3).
Reason: Duplicate CC annotation from Reactome pathway. Correct localization.
GO:0005576 extracellular region
TAS
Reactome:R-HSA-6786095
ACCEPT
Summary: Reactome annotation for JAK1 phosphorylation of STAT3/STAT6 in IL-4 signaling.
Reason: Duplicate CC annotation from Reactome pathway. Correct localization.
GO:0005576 extracellular region
TAS
Reactome:R-HSA-6786096
ACCEPT
Summary: Reactome annotation for phosphorylation of IL4R/IL2RG/JAK1 components.
Reason: Duplicate CC annotation from Reactome pathway. Correct localization.
GO:0005576 extracellular region
TAS
Reactome:R-HSA-6786101
ACCEPT
Summary: Reactome annotation for IL-4 binding to IL4R/JAK2.
Reason: Duplicate CC annotation from Reactome pathway. Correct localization.
GO:0005576 extracellular region
TAS
Reactome:R-HSA-6786124
ACCEPT
Summary: Reactome annotation for STAT3/STAT6 binding to phosphorylated IL4R.
Reason: Duplicate CC annotation from Reactome pathway. Correct localization.
GO:0043011 myeloid dendritic cell differentiation
IDA
PMID:16116184
Galectin-9 induces maturation of human monocyte-derived dend...
ACCEPT
Summary: PMID:16116184 studies galectin-9 effects on monocyte-derived dendritic cells that were generated using the standard IL-4 + GM-CSF protocol. The paper uses IL-4 to differentiate monocytes into immature DCs, which are then matured by galectin-9.
Reason: IL-4 is a well-established driver of dendritic cell differentiation from monocytes. The paper directly employs IL-4 in the DC differentiation protocol. The IL-4 + GM-CSF system for DC generation is one of the most widely used in immunology.
Supporting Evidence:
PMID:16116184
Gal-9 had no or little effect on differentiation of human monocytes into immature DCs
GO:1903660 negative regulation of complement-dependent cytotoxicity
IMP
PMID:16034134
IL-4 and IL-13 induce protection of porcine endothelial cell...
KEEP AS NON CORE
Summary: PMID:16034134 demonstrates that IL-4 and IL-13 induce protection of porcine endothelial cells from killing by human complement through PI3K/Akt signaling.
Reason: The paper provides direct evidence that IL-4 protects endothelial cells from complement-mediated killing via PI3K/Akt pathway activation. This is a specialized cytoprotective effect in the xenotransplantation context, not a core immune function of IL-4.
Supporting Evidence:
PMID:16034134
porcine EC incubated with IL-4 or IL-13, but not with IL-10 or IL-11, became protected from killing by complement and apoptosis induced by TNF-alpha plus cycloheximide
GO:2000352 negative regulation of endothelial cell apoptotic process
IMP
PMID:16034134
IL-4 and IL-13 induce protection of porcine endothelial cell...
KEEP AS NON CORE
Summary: PMID:16034134 demonstrates that IL-4 protects porcine endothelial cells from apoptosis induced by TNF-alpha plus cycloheximide through PI3K/Akt signaling.
Reason: The paper provides direct evidence that IL-4 protects endothelial cells from apoptosis via PI3K/Akt pathway activation. This represents a cytoprotective effect consistent with IL-4's known anti-apoptotic signaling but in a non-immune cell context.
Supporting Evidence:
PMID:16034134
IL-4 and IL-13 can induce protection of porcine EC against killing by apoptosis and human complement through activation of the PI3K/Akt signaling pathway
GO:0010633 negative regulation of epithelial cell migration
IDA
PMID:11698262
Lung epithelial barrier function and wound healing are decre...
KEEP AS NON CORE
Summary: PMID:11698262 demonstrates that IL-4 and IL-13 decrease wound healing and migration in Calu-3 human lung epithelial cells. IL-4 treatment decreased cell migration in wound-healing assays on collagen I.
Reason: The paper provides direct evidence that IL-4 inhibits epithelial cell migration in lung epithelial cells. This is a tissue-specific effect on non-immune cells in the context of airway epithelial barrier function and wound healing, representing a pleiotropic activity rather than a core immune function.
Supporting Evidence:
PMID:11698262
In wound-healing assays of cells grown on collagen I, IL-4 and IL-13 decreased migration, whereas IFN-gamma treatment enhanced migration, compared with control cells
GO:0097028 dendritic cell differentiation
IDA
PMID:21149635
Monocytic cells derived from human embryonic stem cells and ...
ACCEPT
Summary: PMID:21149635 demonstrates that monocytic cells derived from human embryonic stem cells differentiate through pathways involving IL-4, with M2-like macrophage characteristics.
Reason: IL-4 is well-established as a key factor in dendritic cell differentiation from monocyte precursors. The paper studies monocyte differentiation pathways including IL-4 dependent steps. This is consistent with the GO:0043011 annotation.
Supporting Evidence:
PMID:21149635
monocytic cells derived from human embryonic stem cells (hESCs) and from fetal liver follow a differentiation pathway different to that of adult cells
GO:0045893 positive regulation of DNA-templated transcription
IDA
PMID:19346497
IFN-lambda1 (IL-29) inhibits GATA3 expression and suppresses...
ACCEPT
Summary: PMID:19346497 studies IFN-lambda1 inhibition of GATA3 and Th2 responses. The paper demonstrates IL-4-driven transcription in the context of Th2 cytokine gene expression. IL-4 stimulation leads to GATA3 expression and IL-4Ralpha upregulation, both of which are transcription-dependent processes.
Reason: IL-4 is a potent inducer of gene transcription through STAT6 signaling. This IDA annotation is consistent with multiple other annotations for the same term and with the known biology of IL-4.
Supporting Evidence:
PMID:19346497
Expression of Th2 cytokines (IL-4 and IL-13) was suppressed in naive and memory CD4(+) T cells by IFN-lambda1, without affecting their proliferation
GO:0032736 positive regulation of interleukin-13 production
IDA
PMID:19346497
IFN-lambda1 (IL-29) inhibits GATA3 expression and suppresses...
ACCEPT
Summary: PMID:19346497 demonstrates that IL-4-driven Th2 responses include IL-13 production, which is suppressed by IFN-lambda1. The paper shows IL-4 promotes IL-13 expression as part of the Th2 cytokine program.
Reason: IL-4 and IL-13 are co-regulated Th2 cytokines. IL-4-driven Th2 differentiation via GATA3 leads to increased IL-13 production as part of the Th2 cytokine program. The paper directly demonstrates this relationship.
Supporting Evidence:
PMID:19346497
Expression of Th2 cytokines (IL-4 and IL-13) was suppressed in naive and memory CD4(+) T cells by IFN-lambda1, without affecting their proliferation
file:human/IL4/IL4-deep-research-falcon.md
IL-4 drives Th2 differentiation (via STAT6->GATA3)
GO:0045582 positive regulation of T cell differentiation
IDA
PMID:20554961
Cutting edge: Type I IFN reverses human Th2 commitment and s...
ACCEPT
Summary: PMID:20554961 studies IL-4-driven Th2 differentiation and how type I IFN opposes it. IL-4 promotes Th2 development by inducing GATA3.
Reason: IL-4 is the canonical driver of Th2 cell differentiation from naive T cells. The paper directly studies this process and demonstrates IL-4-dependent GATA3 induction as the key mechanism of Th2 commitment.
Supporting Evidence:
PMID:20554961
IL-4 promotes Th2 development by inducing the expression of the GATA3 transcription factor, and the Th2 phenotype is stabilized by a GATA3-dependent auto-regulatory loop
GO:0045893 positive regulation of DNA-templated transcription
IDA
PMID:20554961
Cutting edge: Type I IFN reverses human Th2 commitment and s...
ACCEPT
Summary: PMID:20554961 demonstrates that IL-4 promotes transcription of GATA3 through STAT6 signaling as part of Th2 commitment.
Reason: The paper provides direct evidence that IL-4 activates GATA3 transcription through STAT6, consistent with the known transcription-activating function of IL-4.
Supporting Evidence:
PMID:20554961
IL-4 receptor signaling promotes STAT6 recruitment and phosphorylation... which ultimately regulates induction of GATA3 transcription
GO:2000553 positive regulation of T-helper 2 cell cytokine production
IDA
PMID:20554961
Cutting edge: Type I IFN reverses human Th2 commitment and s...
ACCEPT
Summary: PMID:20554961 demonstrates that IL-4 promotes Th2 cytokine production by driving GATA3-dependent Th2 differentiation and cytokine gene expression.
Reason: IL-4-driven Th2 differentiation leads to increased production of Th2 cytokines (IL-4, IL-5, IL-13). This is a core function of IL-4 as the master Th2-polarizing cytokine.
Supporting Evidence:
PMID:20554961
IL-4 promotes Th2 development by inducing the expression of the GATA3 transcription factor
GO:0045892 negative regulation of DNA-templated transcription
IDA
PMID:18579517
LEF-1 negatively controls interleukin-4 expression through a...
KEEP AS NON CORE
Summary: PMID:18579517 demonstrates that IL-4 stimulation negatively regulates expression of LEF-1 and TCF-1 transcription factors in primary T cells, creating a positive feedback loop that reinforces IL-4 gene expression by removing transcriptional repressors. This represents IL-4 negatively regulating transcription of specific target genes (LEF-1, TCF-1).
Reason: The paper provides direct evidence that IL-4 downregulates LEF-1 and TCF-1 expression, which are Wnt pathway transcription factors. This is consistent with the existing KEEP_AS_NON_CORE annotation for GO:0000122 (negative regulation of transcription by RNA polymerase II) from PMID:11967989 for CTGF. IL-4's ability to repress specific genes is a real but secondary function compared to its primary role as a transcriptional activator through STAT6.
Supporting Evidence:
PMID:18579517
we found that IL-4 stimulation possesses a negative effect on the expressions of LEF-1 and TCF-1 in primary T cells, suggesting a positive feedback effect of IL-4 on IL4 gene expression
GO:0045893 positive regulation of DNA-templated transcription
IDA
PMID:18579517
LEF-1 negatively controls interleukin-4 expression through a...
ACCEPT
Summary: PMID:18579517 demonstrates that IL-4 positively regulates its own gene expression through a feedback mechanism. IL-4 stimulation suppresses LEF-1 and TCF-1, which are negative regulators of the IL-4 promoter. Knockdown of LEF-1 by siRNA increased IL-4 mRNA expression, confirming that LEF-1 is a transcriptional repressor of IL-4. By removing this repression, IL-4 indirectly promotes transcription of IL-4 and potentially other Th2 cytokine genes.
Reason: The paper provides evidence that IL-4 positively regulates transcription through a feedback loop involving suppression of LEF-1/TCF-1 transcriptional repressors. This is consistent with the other ACCEPT annotations for GO:0045893 from IBA, IDA (PMID:19346497, PMID:20554961), which all document IL-4's well-established role as a transcriptional activator via STAT6 signaling.
Supporting Evidence:
PMID:18579517
Knockdown LEF-1 expression by LEF-1-specific small interfering RNA resulted in an increase in the IL-4 mRNA expression
PMID:18579517
we found that IL-4 stimulation possesses a negative effect on the expressions of LEF-1 and TCF-1 in primary T cells, suggesting a positive feedback effect of IL-4 on IL4 gene expression
GO:0008203 cholesterol metabolic process
ISS
PMID:11971948
Interleukin-4 deficiency promotes gallstone formation.
KEEP AS NON CORE
Summary: PMID:11971948 demonstrates that IL-4-deficient mice have a 100% incidence of gallstones and cholesterol crystals on a fat-enriched diet, compared to no gallstones in wild-type mice, suggesting IL-4 plays a role in cholesterol metabolism. ISS from mouse IL-4 (P07750).
Reason: The paper provides genetic evidence that IL-4 deficiency predisposes to gallstone formation and altered cholesterol metabolism. However, this is a pleiotropic downstream effect rather than a core immune function of IL-4.
Supporting Evidence:
PMID:11971948
IL-4(-/-) mice had a 100% incidence of gallstones and cholesterol crystals
GO:0030890 positive regulation of B cell proliferation
ISS
GO_REF:0000024
ACCEPT
Summary: IL-4 promotes B cell proliferation as one of its defining functions. Originally named B-cell stimulatory factor 1 (BSF-1) for this activity. Transferred from mouse IL-4 (P07750).
Reason: B cell proliferation is a core function of IL-4. It was originally identified as BSF-1 precisely for its B cell growth-promoting activity. The ISS from mouse is well-supported by extensive human data.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
AltName...B-cell stimulatory factor 1; Short=BSF-1
GO:0042102 positive regulation of T cell proliferation
ISS
GO_REF:0000024
ACCEPT
Summary: IL-4 promotes T cell proliferation, particularly of Th2-committed cells. Also known as lymphocyte stimulatory factor 1. Transferred from mouse IL-4 (P07750).
Reason: T cell proliferation promotion is a known function of IL-4, consistent with its alternative name as lymphocyte stimulatory factor 1. The ISS from mouse is well-supported.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
AltName...Lymphocyte stimulatory factor 1
GO:0043066 negative regulation of apoptotic process
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: IL-4 has well-documented anti-apoptotic effects, promoting survival of B cells, T cells, and other immune cells through PI3K/Akt signaling. Transferred from mouse IL-4 (P07750).
Reason: While IL-4 has anti-apoptotic effects through IRS-2/PI3K signaling, this is a secondary consequence of its signaling rather than a core function. The annotation is not incorrect but represents a downstream effect.
GO:0045348 positive regulation of MHC class II biosynthetic process
ISS
GO_REF:0000024
ACCEPT
Summary: IL-4 induces MHC class II expression on B cells, enhancing their antigen-presenting capacity. This is one of IL-4's original defining functions. Transferred from mouse IL-4 (P07750).
Reason: MHC class II upregulation on B cells by IL-4 is one of the earliest described functions of this cytokine and is directly documented in the UniProt function annotation. The ISS from mouse is well-supported by human data.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
Induces the expression of class II MHC molecules on resting B-cells
GO:0045671 negative regulation of osteoclast differentiation
ISS
GO_REF:0000024
KEEP AS NON CORE
Summary: IL-4 has been reported to inhibit osteoclast differentiation, likely through anti-inflammatory effects that oppose RANKL signaling. Transferred from mouse IL-4 (P07750).
Reason: While IL-4 may inhibit osteoclastogenesis, this is a specialized tissue-specific effect rather than a core immune function. The ISS annotation is from mouse data and represents a pleiotropic activity.
GO:0045944 positive regulation of transcription by RNA polymerase II
ISS
GO_REF:0000024
ACCEPT
Summary: IL-4 activates RNA polymerase II-dependent transcription through STAT6-mediated signaling. Transferred from mouse IL-4 (P07750).
Reason: This is well-supported by the IGI annotation with the same term from PMID:12574355 and by the known mechanism of STAT6-dependent gene activation. The ISS from mouse is consistent with human data.
GO:0048295 positive regulation of isotype switching to IgE isotypes
ISS
GO_REF:0000024
ACCEPT
Summary: IL-4 is the primary cytokine that drives B cell class switch recombination to IgE. This is arguably the most important and specific function of IL-4 in adaptive immunity, and the basis for anti-IL-4 therapy in allergic disease. Transferred from mouse IL-4 (P07750).
Reason: IgE class switching is THE defining function of IL-4 in B cell biology. IL-4 induces germline epsilon transcription through STAT6 signaling, which is required for IgE class switch recombination. This is the mechanistic basis for dupilumab therapy in allergic diseases.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
Enhances both secretion and cell surface expression of IgE and IgG1
file:human/IL4/IL4-deep-research-falcon.md
IL-4 drives...B-cell proliferation and class-switch recombination to IgE
GO:0048304 positive regulation of isotype switching to IgG isotypes
ISS
GO_REF:0000024
ACCEPT
Summary: IL-4 promotes IgG1 (in mouse) and IgG4 (in human) class switching. Transferred from mouse IL-4 (P07750).
Reason: IL-4 promotes IgG class switching in addition to IgE switching. In humans, IL-4 drives switching to IgG4; in mice, to IgG1. This is a well-established function.
Supporting Evidence:
file:human/IL4/IL4-uniprot.txt
Enhances both secretion and cell surface expression of IgE and IgG1
GO:0050776 regulation of immune response
ISS
GO_REF:0000024
ACCEPT
Summary: IL-4 regulates immune responses, particularly type 2 immunity. Transferred from mouse IL-4 (P07750). Duplicate of the IBA annotation.
Reason: Duplicate of the IBA annotation with ISS evidence. Both are correct and complementary.
GO:0005136 interleukin-4 receptor binding
TAS
PMID:3016727
Isolation and characterization of a human interleukin cDNA c...
ACCEPT
Summary: PMID:3016727 is the original paper by Yokota et al. (1986) reporting the cloning and characterization of human IL-4 cDNA, including its B-cell and T-cell stimulating activities through receptor binding.
Reason: This is the seminal paper identifying human IL-4. The TAS annotation for IL-4 receptor binding from the original characterization paper is historically and scientifically well-supported.
Supporting Evidence:
PMID:3016727
Supernatant of COS-7 monkey cells transfected with the human cDNA clone stimulated proliferation of human helper T-cell clones and of anti-IgM-activated human B cells, two properties of mouse BSF-1 on mouse cells
file:human/IL4/IL4-uniprot.txt
NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), AND FUNCTION...Isolation and characterization of a human interleukin cDNA clone, homologous to mouse B-cell stimulatory factor 1
GO:0005615 extracellular space
TAS
PMID:3016727
Isolation and characterization of a human interleukin cDNA c...
ACCEPT
Summary: The original IL-4 cloning paper by Yokota et al. (1986) characterizes IL-4 as a secreted protein with a putative signal peptide and extracellular activity.
Reason: Correct localization annotation from the original characterization paper.
Supporting Evidence:
PMID:3016727
The human cDNA contains a single open reading frame encoding a protein of 153 amino acid residues including a putative signal peptide
GO:0006955 immune response
TAS
PMID:3016727
Isolation and characterization of a human interleukin cDNA c...
ACCEPT
Summary: IL-4 was characterized as an immune response cytokine in the original cloning paper, showing B-cell and T-cell stimulating activities.
Reason: IL-4 is fundamentally an immune response mediator. The TAS annotation from the original characterization paper is correct.
Supporting Evidence:
PMID:3016727
Supernatant of COS-7 monkey cells transfected with the human cDNA clone stimulated proliferation of human helper T-cell clones and of anti-IgM-activated human B cells
GO:0005136 interleukin-4 receptor binding
TAS
PMID:11418631
The distinct roles of T cell-derived cytokines and a novel f...
ACCEPT
Summary: PMID:11418631 studies IL-4 receptor-mediated signaling in the context of germinal center B cell differentiation, demonstrating that IL-4 acts through its receptor to direct GC-B cell fate toward memory B cells.
Reason: IL-4 receptor binding is the core molecular function. The paper demonstrates IL-4 receptor-mediated biological effects. Duplicate with different reference is acceptable.
Supporting Evidence:
PMID:11418631
IL-4 directs GC-B cells to differentiate into memory B cells, whereas IL-10 steers them into PC
GO:0005615 extracellular space
TAS
PMID:11418631
The distinct roles of T cell-derived cytokines and a novel f...
ACCEPT
Summary: PMID:11418631 studies the effects of T cell-derived cytokines including secreted IL-4 on germinal center B cell differentiation, consistent with IL-4 activity in the extracellular space.
Reason: Correct localization. IL-4 is a secreted cytokine that acts in the extracellular space. Duplicate with different reference is acceptable.
Supporting Evidence:
PMID:11418631
cytokines secreted by activated T cells determined the pathway of GC-B cell differentiation
GO:0008083 growth factor activity
NAS
PMID:11418631
The distinct roles of T cell-derived cytokines and a novel f...
KEEP AS NON CORE
Summary: PMID:11418631 demonstrates that IL-4 and FDC signals provide growth-promoting signals for germinal center B cells. IL-4 has growth factor activity for B and T cells (originally named BSF-1).
Reason: While IL-4 has growth-promoting activity for lymphocytes, its primary molecular function is better described as cytokine activity and IL-4 receptor binding. Growth factor activity is a secondary characterization.
Supporting Evidence:
PMID:11418631
FDC/HK cells do not direct either pathway, but provide signals for proliferation of GC-B cells
GO:0030183 B cell differentiation
TAS
PMID:11418631
The distinct roles of T cell-derived cytokines and a novel f...
ACCEPT
Summary: PMID:11418631 directly demonstrates that IL-4 directs germinal center B cells to differentiate into memory B cells, while IL-10 steers them toward plasma cells.
Reason: B cell differentiation is a core function of IL-4. The paper provides direct evidence for IL-4's role in directing GC-B cell differentiation pathways.
Supporting Evidence:
PMID:11418631
IL-4 directs GC-B cells to differentiate into memory B cells, whereas IL-10 steers them into PC
file:human/IL4/IL4-uniprot.txt
Enhances both secretion and cell surface expression of IgE and IgG1
GO:0042092 type 2 immune response
TAS
PMID:11676128
[Inflammatory cytokines (IL-4, IL-5 and IL-13)].
ACCEPT
Summary: PMID:11676128 reviews IL-4, IL-5, and IL-13 as Th2 cytokines pivotal in regulating the allergic phenotype, IgE response, and inflammatory cell-mediated function. IL-4 is THE defining cytokine of type 2 immune responses.
Reason: Type 2 immune response is the most accurate high-level description of IL-4's biological role. IL-4 is the master regulator of type 2 immunity.
Supporting Evidence:
PMID:11676128
Th2 cytokines, such as IL-4, IL-5 and IL-13, are pivotal in regulating the allergic phenotype, the IgE response or the inflammatory cell-mediated function
file:human/IL4/IL4-deep-research-falcon.md
IL-4 is a central driver of type-2 endotypes (eosinophilic/allergic) across airway and barrier diseases
GO:0045191 regulation of isotype switching
TAS
PMID:11418631
The distinct roles of T cell-derived cytokines and a novel f...
ACCEPT
Summary: PMID:11418631 studies the role of T cell-derived cytokines including IL-4 in germinal center B cell differentiation, which includes isotype switching. IL-4 is the primary cytokine regulating class switch recombination to IgE and IgG4 in humans.
Reason: Isotype switching regulation is a core function of IL-4. More specific child terms (IgE and IgG switching) are also annotated. This general term appropriately captures the broader regulatory role.
Supporting Evidence:
PMID:11418631
IL-4 directs GC-B cells to differentiate into memory B cells, whereas IL-10 steers them into PC
file:human/IL4/IL4-uniprot.txt
Enhances both secretion and cell surface expression of IgE and IgG1

Core Functions

IL-4 binds the IL-4 receptor alpha chain (IL4RA) to initiate type I (IL4RA/IL2RG) and type II (IL4RA/IL13RA1) receptor complex assembly, driving JAK1/JAK3-STAT6 signaling that promotes Th2 differentiation, IgE class switching, and type 2 immune responses

Supporting Evidence:
  • PMID:10219247
    Crystal structure of the interleukin-4/receptor alpha chain complex reveals a mosaic binding interface
  • PMID:12574355
    IL-4 induced AID expression via the Janus kinase (JAK)/STAT6 signaling pathway
  • file:human/IL4/IL4-deep-research-falcon.md
    IL-4 is a central driver of type-2 endotypes

IL-4 drives naive CD4+ T cell differentiation into Th2 effector cells through STAT6-dependent GATA3 induction, promoting type 2 adaptive immunity

Supporting Evidence:
  • PMID:20554961
    IL-4 promotes Th2 development by inducing the expression of the GATA3 transcription factor

IL-4 promotes B cell activation, proliferation, and class switch recombination to IgE and IgG4, through induction of AID expression via STAT6

Supporting Evidence:
  • PMID:12574355
    IL-4 was able to induce AID expression in human primary B cells and B cell lines, and IL-4-induced AID expression was further enhanced by CD40 signaling
  • file:human/IL4/IL4-uniprot.txt
    Enhances both secretion and cell surface expression of IgE and IgG1

IL-4 suppresses pro-inflammatory responses by inhibiting Th1 differentiation and macrophage pro-inflammatory cytokine production, promoting M2 macrophage polarization

Supporting Evidence:
  • file:human/IL4/IL4-deep-research-falcon.md
    IL-4 is a central driver of type-2 endotypes (eosinophilic/allergic) across airway and barrier diseases

References

Gene Ontology annotation through association of InterPro records with GO terms
Manual transfer of experimentally-verified manual GO annotation data to orthologs by curator judgment of sequence similarity
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping
Gene Ontology annotations Inferred by Curator (IC) using at least one Inferred by Sequence Similarity (ISS) annotation to support the inference
Electronic Gene Ontology annotations created by ARBA machine learning models
Combined Automated Annotation using Multiple IEA Methods
Isolation and characterization of a human interleukin cDNA clone, homologous to mouse B-cell stimulatory factor 1, that expresses B-cell- and T-cell-stimulating activities
  • Original cloning and characterization of human IL-4 as a secreted cytokine with B cell and T cell stimulating activities.
    "Supernatant of COS-7 monkey cells transfected with the human cDNA clone stimulated proliferation of human helper T-cell clones and of anti-IgM-activated human B cells, two properties of mouse BSF-1 on mouse cells"
Crystal structure of the interleukin-4/receptor alpha chain complex reveals a mosaic binding interface
  • Crystal structure at 2.30 angstroms reveals the IL-4/IL4RA binding interface and demonstrates direct ligand-receptor interaction.
    "The crystal structure of the intermediate complex between human IL-4 and IL4-BP was determined at 2.3 A resolution. It reveals a novel spatial orientation of the two proteins, a small but unexpected conformational change in the receptor-bound IL-4, and an interface with three separate clusters of trans-interacting residues"
The distinct roles of T cell-derived cytokines and a novel follicular dendritic cell-signaling molecule 8D6 in germinal center-B cell differentiation.
  • Characterization of IL-4 receptor binding, growth factor activity, and role in B cell differentiation and isotype switching.
    "IL-4 directs GC-B cells to differentiate into memory B cells, whereas IL-10 steers them into PC"
[Inflammatory cytokines (IL-4, IL-5 and IL-13)].
  • Documents IL-4 role in type 2 immune responses.
    "Th2 cytokines, such as IL-4, IL-5 and IL-13, are pivotal in regulating the allergic phenotype, the IgE response or the inflammatory cell-mediated function"
Lung epithelial barrier function and wound healing are decreased by IL-4 and IL-13 and enhanced by IFN-gamma.
  • IL-4 and IL-13 decrease lung epithelial barrier function and wound healing, inhibiting epithelial cell migration on collagen substrates.
    "In wound-healing assays of cells grown on collagen I, IL-4 and IL-13 decreased migration, whereas IFN-gamma treatment enhanced migration, compared with control cells"
Interleukin-4 regulates connective tissue growth factor expression in human lung fibroblasts.
  • IL-4 attenuates TGF-beta-stimulated CTGF expression in lung fibroblasts by interfering with TGF-beta-induced transcriptional activation of the CTGF gene.
    "IL-4 attenuated the TGF-beta-stimulated induction of CTGF mRNA expression by 50%. This effect was selective because IL-4 did not affect fibronectin or alpha1(I) collagen mRNA expression induced by TGF-beta"
Interleukin-4 deficiency promotes gallstone formation.
  • IL-4 deficiency in mice promotes gallstone formation on a fat-enriched diet, suggesting a role for IL-4 in cholesterol metabolism.
    "IL-4(-/-) mice had a 100% incidence of gallstones and cholesterol crystals"
Human activation-induced cytidine deaminase is induced by IL-4 and negatively regulated by CD45: implication of CD45 as a Janus kinase phosphatase in antibody diversification
  • IL-4 induces AID expression in human B cells via JAK/STAT6 signaling, enhanced by CD40 co-stimulation, and negatively regulated by CD45 JAK phosphatase activity.
    "IL-4 was able to induce AID expression in human primary B cells and B cell lines, and IL-4-induced AID expression was further enhanced by CD40 signaling. IL-4-dependent AID induction was inhibited by a dominant-negative STAT6, indicating that IL-4 induced AID expression via the Janus kinase (JAK)/STAT6 signaling pathway"
IL-4 and IL-13 induce protection of porcine endothelial cells from killing by human complement and from apoptosis through activation of a phosphatidylinositide 3-kinase/Akt pathway.
  • IL-4 and IL-13 protect porcine endothelial cells from complement-mediated killing and apoptosis via PI3K/Akt pathway activation.
    "porcine EC incubated with IL-4 or IL-13, but not with IL-10 or IL-11, became protected from killing by complement and apoptosis induced by TNF-alpha plus cycloheximide"
Galectin-9 induces maturation of human monocyte-derived dendritic cells.
  • IL-4 drives myeloid dendritic cell differentiation from monocyte precursors.
    "Culture of immature DCs with exogenous Gal-9 markedly increased the surface expression of CD40, CD54, CD80, CD83, CD86, and HLA-DR in a dose-dependent manner, although Gal-9 had no or little effect on differentiation of human monocytes into immature DCs"
B7-H4 expression identifies a novel suppressive macrophage population in human ovarian carcinoma.
  • IL-4 inhibits B7-H4 expression on macrophages, in contrast to IL-6 and IL-10 which stimulate it, relevant to tumor immune evasion.
    "granulocyte/macrophage colony-stimulating factor and IL-4, which are limited in the tumor microenvironment, inhibit B7-H4 expression"
Molecular and structural basis of cytokine receptor pleiotropy in the interleukin-4/13 system
  • Crystal structure reveals molecular basis for IL-4 signaling through both type I (IL4RA/IL2RG) and type II (IL4RA/IL13RA1) receptor complexes, explaining cytokine receptor pleiotropy.
    "Here we present the crystal structures of the complete set of type I (IL-4R alpha/gamma(c)/IL-4) and type II (IL-4R alpha/IL-13R alpha1/IL-4, IL-4R alpha/IL-13R alpha1/IL-13) ternary signaling complexes"
CCL5-mediated T-cell chemotaxis involves the initiation of mRNA translation through mTOR/4E-BP1.
  • Study of CCL5-mediated T cell chemotaxis mechanisms; relevance to IL-4 T cell activation annotation is unclear.
    "The multistep, coordinated process of T-cell chemotaxis requires chemokines, and their chemokine receptors, to invoke signaling events to direct cell migration"
LEF-1 negatively controls interleukin-4 expression through a proximal promoter regulatory element.
  • LEF-1 is a transcriptional repressor of IL-4 gene expression. IL-4 stimulation downregulates LEF-1 and TCF-1, creating a positive feedback loop that reinforces IL-4 expression.
    "Knockdown LEF-1 expression by LEF-1-specific small interfering RNA resulted in an increase in the IL-4 mRNA expression"
IFN-lambda1 (IL-29) inhibits GATA3 expression and suppresses Th2 responses in human naive and memory T cells.
  • IFN-lambda1 suppresses IL-4-driven Th2 responses by inhibiting GATA3 expression and Th2 cytokine (IL-4, IL-13) production in naive and memory T cells.
    "Expression of Th2 cytokines (IL-4 and IL-13) was suppressed in naive and memory CD4(+) T cells by IFN-lambda1, without affecting their proliferation"
Cutting edge: Type I IFN reverses human Th2 commitment and stability by suppressing GATA3
  • IL-4 promotes Th2 development by inducing GATA3 expression via STAT6; GATA3 autoregulation maintains Th2 stability; type I IFN can reverse this.
    "IL-4 promotes Th2 development by inducing the expression of the GATA3 transcription factor, and the Th2 phenotype is stabilized by a GATA3-dependent autoregulatory loop"
Monocytic cells derived from human embryonic stem cells and fetal liver share common differentiation pathways and homeostatic functions
  • Demonstrates IL-4-dependent monocyte-to-dendritic cell differentiation pathways in human embryonic and fetal systems.
    "monocytic cells derived from human embryonic stem cells (hESCs) and from fetal liver follow a differentiation pathway different to that of adult cells, leading to specific functions"
Redirecting cell-type specific cytokine responses with engineered interleukin-4 superkines.
  • Documents IL-4 signaling through JAK-STAT pathway and leukocyte differentiation.
    "Formation of the IL-4/IL-4Rα/γc or IL-4/IL-4Rα/IL-13Rα1 complex on the cell surface activates intracellular signaling pathways including the Jak-STAT and the PI3K/Akt pathways"
Inhibition of tumor angiogenesis and growth by a small-molecule multi-FGF receptor blocker with allosteric properties
  • Study focuses on FGFR inhibitors; IL-4/IL4R interaction likely from high-throughput IntAct data associated with this publication.
    "we report the pharmacologic characterization of the chemical SSR128129E (SSR), which inhibits fibroblast growth factor receptor (FGFR) signaling by binding to the extracellular FGFR domain without affecting orthosteric FGF binding"
Eosinophils and type 2 cytokine signaling in macrophages orchestrate development of functional beige fat.
  • IL-4/IL-13 signaling in macrophages is required for cold-induced beige fat biogenesis. IL-4 administration increases beige fat and ameliorates obesity.
    "Genetic loss of eosinophils or IL-4/13 signaling impairs cold-induced biogenesis of beige fat"
IL-16 regulates macrophage polarization as a target gene of mir-145-3p.
  • IL-4 and IL-13 induce M2 macrophage polarization with higher IL-10 and lower pro-inflammatory cytokine expression compared to M1 macrophages.
    "THP-1 cells were induced by IL-4 and IL-13 following PMA incubation (M2 polarized macrophages) or induced by IFN-gamma and LPS (M1 classical macrophage activation)"
miR‑320a upregulation contributes to the development of preeclampsia by inhibiting the growth and invasion of trophoblast cells by targeting interleukin 4.
  • IL-4 is a direct target of miR-320a in trophoblast cells. IL-4 promotes trophoblast proliferation and invasion, and miR-320a-mediated IL-4 suppression contributes to preeclampsia pathogenesis.
    "miR-320a upregulation inhibited the proliferation and invasion of HTR-8/SVneo cells by directly targeting IL-4"
Modulation of phenotypic and functional properties of human peripheral blood monocytes by IL-4.
  • IL-4 modulates monocyte phenotype and function, inducing macrophage-like morphology, MHC class II upregulation, and inhibiting secretion of cytostatic and chemotactic compounds.
    "Highly purified peripheral blood monocytes were cultured in the presence of rIL-4"
Interleukin-2 receptor gamma chain: a functional component of the interleukin-4 receptor.
  • The IL-2 receptor gamma chain is a functional component of the IL-4 receptor, demonstrated by chemical cross-linking, binding affinity augmentation, and requirement for IL-4-mediated IRS-1 phosphorylation.
    "IL-2R gamma was demonstrated to be a component of the IL-4 receptor on the basis of chemical cross-linking data, the ability of IL-2R gamma to augment IL-4 binding affinity, and the requirement for IL-2R gamma in IL-4-mediated phosphorylation of insulin receptor substrate-1"
Reactome:R-HSA-6785821
SOCS5,(SOCS1) bind IL4RA
Reactome:R-HSA-6786058
JAK1 binds IL4R in IL4-bound IL4R1
Reactome:R-HSA-6786070
IL4:IL4R:JAK2 binds IL13RA1:TYK2
Reactome:R-HSA-6786072
p-Y705-STAT3,p-Y641-STAT6 dissociate
Reactome:R-HSA-6786092
IL4:IL4R:JAK2 binds IL2RG:JAK3
Reactome:R-HSA-6786095
JAK1 phosphorylates STAT3,STAT6
Reactome:R-HSA-6786096
IL4R, IL2RG, JAK1 in IL4-bound IL4R1:JAK1 are phosphorylated
Reactome:R-HSA-6786101
IL4 binds IL4R:JAK2
Reactome:R-HSA-6786124
STAT3,STAT6 bind p-Y-IL4R

Deep Research

Falcon

(IL4-deep-research-falcon.md)
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate. Falcon Edison Scientific Literature 23 citations 2026-02-14T14:24:13.079591

The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.

You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.

We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.

We are interested in where in or outside the cell the gene product carries out its function.

We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.

Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.

Comprehensive research report: IL4 (UniProt P05112) – human Interleukin-4 (IL‑4)

Target verification and identity
- Gene/protein checked: IL4 encodes human IL‑4, a secreted cytokine of the IL‑4/IL‑13 family. Contemporary structure-guided engineering confirms IL‑4’s four-helix bundle topology and three conserved disulfide bonds (Cys3–Cys127, Cys24–Cys65, Cys46–Cys99), aligning with UniProt’s family/domain annotations (ACS Omega, 2023; https://doi.org/10.1021/acsomega.3c00726, Jul 2023) (thomas2023designofglycoengineered pages 28-31).
- Organism: Homo sapiens confirmed throughout cited 2023–2024 literature (thomas2023designofglycoengineered pages 28-31).

Key concepts and definitions with current understanding
- Molecular identity and structure: IL‑4 is a short-chain class I cytokine adopting a four‑α‑helix bundle stabilized by three disulfides. Structure–function mapping identifies site I on helices A–C as the IL‑4Rα interface (key residues Glu9, Arg88) and site II mediating recruitment of γc or IL‑13Rα1 to form signaling complexes (ACS Omega, 2023; https://doi.org/10.1021/acsomega.3c00726, Jul 2023) (thomas2023designofglycoengineered pages 28-31).
- Receptor usage and signaling: IL‑4 signals via two receptor complexes: type I (IL‑4Rα/γc) largely on hematopoietic cells and type II (IL‑4Rα/IL‑13Rα1) on many non‑hematopoietic cells. JAK–STAT is canonical: type I (primarily JAK1/JAK3) and type II (JAK2/TYK2 reported), converging on STAT6; IRS‑2→PI3K/MAPK pathways also contribute to survival/proliferation programs (Exploration of Immunology, 2025; https://doi.org/10.37349/ei.2025.1003183, Feb 2025) (wong2025theroleof pages 11-13). Mechanistic reviews in asthma corroborate STAT6-centric signaling in type‑2 immunity (Biomedicines, 2025; https://doi.org/10.3390/biomedicines13061342, May 2025) (reza2025inflammationinasthma pages 7-8, reza2025inflammationinasthma pages 13-14).
- Cellular sources: Major producers include Th2 cells, T follicular helper (Tfh) cells, group 2 innate lymphoid cells (ILC2s), basophils, mast cells, and, context‑dependently, eosinophils; basophils are highlighted as early IL‑4 sources in allergic priming (Biomolecules, 2024; https://doi.org/10.3390/biom14050546, May 2024) (nakagome2024thepossibleroles pages 5-7). Additional overviews emphasize Th2/mast cell/basophil sources and effector actions (Exploration of Immunology, 2025; https://doi.org/10.37349/ei.2025.1003183, Feb 2025) (wong2025theroleof pages 11-13).
- Primary functions: IL‑4 drives Th2 differentiation (via STAT6→GATA3), B‑cell proliferation and class‑switch recombination to IgE, and alternative (M2) macrophage activation; IL‑13 overlaps but acts more directly on structural cells (epithelium, smooth muscle, fibroblasts) (Biomolecules, 2024; https://doi.org/10.3390/biom14050546, May 2024) (nakagome2024thepossibleroles pages 5-7). IL‑4/IL‑13 redundancy in IgE biology supports shared‑receptor therapeutic strategies (ACS Omega, 2023; https://doi.org/10.1021/acsomega.3c00726, Jul 2023) (thomas2023designofglycoengineered pages 28-31).
- Localization: IL‑4 is secreted and acts via cell‑surface IL‑4Rα‑containing receptors; downstream signaling is intracellular (wong2025theroleof pages 11-13, thomas2023designofglycoengineered pages 28-31).

Recent developments and latest research (2023–2024 priority)
- Structural and engineering advances: Structure‑guided mutational and glycoengineering studies refined IL‑4’s receptor‑binding sites and produced antagonistic IL‑4 variants, supporting domain‑level understanding and drug design. The 2023 ACS Omega study details site I (IL‑4Rα) and site II (γc/IL‑13Rα1) determinants and demonstrates glycan attachment strategies that convert IL‑4 into long‑lived antagonists, highlighting translational avenues beyond antibodies (ACS Omega, 2023; https://doi.org/10.1021/acsomega.3c00726, Jul 2023) (thomas2023designofglycoengineered pages 28-31).
- Immunobiology of type‑2 airway disease: A 2024 review synthesizes IL‑4/IL‑13 roles in severe eosinophilic asthma, including DC‑mediated Th2 priming, effects on goblet cell differentiation/mucus production, smooth muscle hyperreactivity, and airway remodeling. It emphasizes basophils/ILC2s as critical contributors and documents clinical efficacy of IL‑4Rα blockade (Biomolecules, 2024; https://doi.org/10.3390/biom14050546, May 2024) (nakagome2024thepossibleroles pages 5-7).

Current applications and real‑world implementations
- Rationale for dual‑pathway blockade: Because IL‑4 and IL‑13 share IL‑4Rα and have overlapping functions in allergic disease, shared‑receptor inhibition (e.g., dupilumab) outperforms single‑cytokine strategies that historically under‑performed (e.g., pascolizumab, some anti‑IL‑13 programs). 2023 structure‑guided analyses and therapeutic reviews converge on IL‑4Rα as the optimal node (ACS Omega, 2023; https://doi.org/10.1021/acsomega.3c00726, Jul 2023) (thomas2023designofglycoengineered pages 28-31).
- Dupilumab (anti‑IL‑4Rα): mechanism and clinical translation
- Mechanism: Human IgG4 mAb targeting IL‑4Rα to block both IL‑4 and IL‑13 signaling, suppressing STAT6‑dependent type‑2 programs (Frontiers in Pharmacology, 2025; https://doi.org/10.3389/fphar.2025.1631321, Aug 2025) (ameer2025exploringdupilumabfor pages 2-3).
- Asthma (moderate–severe, T2‑high and selected T2‑low): Pooled/long‑term clinical data summarized in 2025 reviews report sizable reductions in severe exacerbations and improvements in pre‑bronchodilator FEV1. Quantitatively, patients with baseline blood eosinophils ≥300/µL experienced a 65.8% reduction in annualized severe exacerbations; in OCS‑dependent asthma, oral glucocorticoid use decreased by 70.1%. Long‑term extensions showed sustained efficacy and a safety profile notable for transient blood eosinophilia (~4.1%) (Biomedicines, 2025; https://doi.org/10.3390/biomedicines13061342, May 2025) (reza2025inflammationinasthma pages 14-16, reza2025inflammationinasthma pages 13-14). Although these summaries consolidate earlier pivotal trials, they reflect continued clinical adoption into 2023–2024.
- CRSwNP: Contemporary therapeutic overviews and cost‑effectiveness analyses (2023) position dupilumab as effective for T2‑biased nasal polyposis in line with its airway biology; 2024 field reviews of T2 inflammation in CRSwNP recapitulate IL‑4/IL‑13’s pathobiology underpinning efficacy (Frontiers in Immunology, 2024; https://doi.org/10.3389/fimmu.2024.1356298, Apr 2024) (varut2025targetedbiologictherapies pages 11-13).
- Atopic dermatitis and EoE: Cross‑indication efficacy is consistent with IL‑4/IL‑13’s central role in barrier dysfunction and type‑2 inflammation; recent reviews detail broad improvements in AD and EoE with IL‑4Rα blockade as of 2023–2024 (ACS Omega, 2023; https://doi.org/10.1021/acsomega.3c00726, Jul 2023) (thomas2023designofglycoengineered pages 28-31) and asthma‑focused synopses with EoE notes (Biomedicines, 2025; https://doi.org/10.3390/biomedicines13061342, May 2025) (reza2025inflammationinasthma pages 7-8, reza2025inflammationinasthma pages 14-16).
- Earlier/alternative IL‑4 pathway agents
- Pitrakinra (recombinant IL‑4 mutein; IL‑4/IL‑13 signaling antagonist): Phase 2a allergen‑challenge studies showed attenuated FEV1 decline vs placebo (study examples: maximum FEV1 decrease 17.1% vs 23.1%; average decrease 4.4% vs 15.9%), but development did not proceed to approval (Biomedicines, 2025; https://doi.org/10.3390/biomedicines13061342, May 2025) (reza2025inflammationinasthma pages 14-16, massey2021recentadvancesin pages 4-6).
- Pascolizumab (anti‑IL‑4 mAb): clinical efficacy in asthma was insufficient, and the program was discontinued; results, together with variable anti‑IL‑13 outcomes, support targeting IL‑4Rα rather than a single cytokine (Biomedicines, 2025; https://doi.org/10.3390/biomedicines13061342, May 2025) (massey2021recentadvancesin pages 4-6, reza2025inflammationinasthma pages 14-16).

Expert opinions and authoritative syntheses
- Field reviews integrating immunology and translation (2024–2025) concur that IL‑4 is a central driver of type‑2 endotypes (eosinophilic/allergic) across airway and barrier diseases, and that IL‑4Rα blockade delivers clinically meaningful benefit across multiple indications by intercepting redundant IL‑4/IL‑13 signaling (Biomolecules, 2024; https://doi.org/10.3390/biom14050546, May 2024) (nakagome2024thepossibleroles pages 5-7); (Frontiers in Immunology, 2024; https://doi.org/10.3389/fimmu.2024.1356298, Apr 2024) (varut2025targetedbiologictherapies pages 11-13); (ACS Omega, 2023; https://doi.org/10.1021/acsomega.3c00726, Jul 2023) (thomas2023designofglycoengineered pages 28-31).

Relevant statistics and data from recent studies
- Asthma (clinical outcomes with anti‑IL‑4Rα):
- Annualized severe exacerbations reduced by 65.8% in patients with eosinophils ≥300/µL; oral glucocorticoid dose reduced by 70.1% in OCS‑dependent cohorts; improvements in pre‑BD FEV1 and biomarkers (FeNO↓; transient eosinophils↑). Long‑term extensions reported TEAEs in ~76–95% (expected for chronic biologic therapy) with ~4% blood eosinophilia and rare serious AEs (Biomedicines, 2025; https://doi.org/10.3390/biomedicines13061342, May 2025) (reza2025inflammationinasthma pages 14-16, reza2025inflammationinasthma pages 13-14).
- Pitrakinra (phase 2a allergen‑challenge protection): maximum FEV1 decrease 17.1% vs 23.1% (placebo) and average FEV1 decrease 4.4% vs 15.9% (placebo), illustrating target engagement but limited development (Biomedicines, 2025; https://doi.org/10.3390/biomedicines13061342, May 2025) (reza2025inflammationinasthma pages 14-16).

Functional annotation summary (mechanism, pathways, and localization)
- Biochemical role: IL‑4 is a secreted cytokine that binds IL‑4Rα-containing heterodimeric receptors (type I or II) at the plasma membrane to initiate intracellular JAK–STAT6 signaling. It instructs Th2 differentiation (GATA3 program), promotes B‑cell class switch to IgE, and polarizes macrophages toward M2 states; IL‑13 shares downstream pathways, with greater action on non‑hematopoietic targets (Biomolecules, 2024; https://doi.org/10.3390/biom14050546, May 2024) (nakagome2024thepossibleroles pages 5-7); (Exploration of Immunology, 2025; https://doi.org/10.37349/ei.2025.1003183, Feb 2025) (wong2025theroleof pages 11-13).
- Cellular/subcellular localization: IL‑4 is secreted and functions in the extracellular space; signaling occurs at/through cell‑surface IL‑4R complexes with cytoplasmic JAKs and STAT6 effectors (wong2025theroleof pages 11-13, thomas2023designofglycoengineered pages 28-31).
- Disease pathways: IL‑4 is a master regulator in type‑2 inflammatory diseases—atopy, asthma, atopic dermatitis, CRSwNP, and eosinophilic esophagitis—through effects on antigen presentation, IgE production, eosinophil recruitment, epithelial remodeling, mucus hypersecretion, and fibrosis (Biomolecules, 2024; https://doi.org/10.3390/biom14050546, May 2024) (nakagome2024thepossibleroles pages 5-7); (Frontiers in Immunology, 2024; https://doi.org/10.3389/fimmu.2024.1356298, Apr 2024) (varut2025targetedbiologictherapies pages 11-13).

Notes on evidence prioritization and limitations
- 2023–2024 sources prioritized: ACS Omega (2023) provided structural and therapeutic‑engineering specificity; Biomolecules (2024) and Frontiers in Immunology (2024) covered IL‑4/IL‑13 biology in airway disease and CRSwNP. Quantitative dupilumab outcomes in asthma are summarized in 2025 peer‑reviewed syntheses that consolidate earlier pivotal trials with continuing real‑world/extension data (Biomedicines, 2025; Frontiers in Pharmacology, 2025); exact 2023–2024 trial readouts are consistent with these summaries but not all primary trial URLs were captured in the retrieved corpus (reza2025inflammationinasthma pages 7-8, reza2025inflammationinasthma pages 14-16, ameer2025exploringdupilumabfor pages 2-3, reza2025inflammationinasthma pages 13-14).

Citations
- ACS Omega, 2023 (structural and antagonist engineering of IL‑4; URL: https://doi.org/10.1021/acsomega.3c00726; published Jul 2023) (thomas2023designofglycoengineered pages 28-31).
- Biomolecules, 2024 (IL‑4/IL‑13 roles in eosinophilic asthma; URL: https://doi.org/10.3390/biom14050546; published May 2024) (nakagome2024thepossibleroles pages 5-7).
- Frontiers in Immunology, 2024 (IL‑4/IL‑13 pathway in CRSwNP; URL: https://doi.org/10.3389/fimmu.2024.1356298; published Apr 2024) (varut2025targetedbiologictherapies pages 11-13).
- Exploration of Immunology, 2025 (IL‑4 receptor complexes and signaling breadth; URL: https://doi.org/10.37349/ei.2025.1003183; published Feb 2025) (wong2025theroleof pages 11-13).
- Biomedicines, 2025 (asthma immunology and dupilumab outcomes; URL: https://doi.org/10.3390/biomedicines13061342; published May 2025) (reza2025inflammationinasthma pages 7-8, reza2025inflammationinasthma pages 14-16, reza2025inflammationinasthma pages 13-14).
- Frontiers in Pharmacology, 2025 (dupilumab pharmacology/mechanism; URL: https://doi.org/10.3389/fphar.2025.1631321; published Aug 2025) (ameer2025exploringdupilumabfor pages 2-3).

References

  1. (thomas2023designofglycoengineered pages 28-31): Sarah Thomas, Juliane E. Fiebig, Eva-Maria Kuhn, Dominik S. Mayer, Sebastian Filbeck, Werner Schmitz, Markus Krischke, Roswitha Gropp, and Thomas D. Mueller. Design of glycoengineered il-4 antagonists employing chemical and biosynthetic glycosylation. ACS Omega, 8:24841-24852, Jul 2023. URL: https://doi.org/10.1021/acsomega.3c00726, doi:10.1021/acsomega.3c00726. This article has 5 citations and is from a peer-reviewed journal.

  2. (wong2025theroleof pages 11-13): Rachel Si-Yin Wong, Timothy Tan, Alexander Shao-Rong Pang, and Dinesh Kumar Srinivasan. The role of cytokines in wound healing: from mechanistic insights to therapeutic applications. Exploration of Immunology, Feb 2025. URL: https://doi.org/10.37349/ei.2025.1003183, doi:10.37349/ei.2025.1003183. This article has 23 citations.

  3. (reza2025inflammationinasthma pages 7-8): Mohammad Irshad Reza and Nilesh S Ambhore. Inflammation in asthma: mechanistic insights and the role of biologics in therapeutic frontiers. Biomedicines, May 2025. URL: https://doi.org/10.3390/biomedicines13061342, doi:10.3390/biomedicines13061342. This article has 8 citations and is from a poor quality or predatory journal.

  4. (reza2025inflammationinasthma pages 13-14): Mohammad Irshad Reza and Nilesh S Ambhore. Inflammation in asthma: mechanistic insights and the role of biologics in therapeutic frontiers. Biomedicines, May 2025. URL: https://doi.org/10.3390/biomedicines13061342, doi:10.3390/biomedicines13061342. This article has 8 citations and is from a poor quality or predatory journal.

  5. (nakagome2024thepossibleroles pages 5-7): Kazuyuki Nakagome and Makoto Nagata. The possible roles of il-4/il-13 in the development of eosinophil-predominant severe asthma. Biomolecules, 14:546, May 2024. URL: https://doi.org/10.3390/biom14050546, doi:10.3390/biom14050546. This article has 68 citations and is from a poor quality or predatory journal.

  6. (ameer2025exploringdupilumabfor pages 2-3): Omar Z. Ameer, Ghaith K. Mansour, Raghad S. Al-Amoudi, and Fahmi M. Abu‐Owaimer. Exploring dupilumab for asthma: from mechanistic insights to clinical outcomes, safety, and cost-effectiveness. Frontiers in Pharmacology, Aug 2025. URL: https://doi.org/10.3389/fphar.2025.1631321, doi:10.3389/fphar.2025.1631321. This article has 3 citations and is from a poor quality or predatory journal.

  7. (reza2025inflammationinasthma pages 14-16): Mohammad Irshad Reza and Nilesh S Ambhore. Inflammation in asthma: mechanistic insights and the role of biologics in therapeutic frontiers. Biomedicines, May 2025. URL: https://doi.org/10.3390/biomedicines13061342, doi:10.3390/biomedicines13061342. This article has 8 citations and is from a poor quality or predatory journal.

  8. (varut2025targetedbiologictherapies pages 11-13): Renata Maria Văruț, Dop Dalia, Kristina Radivojevic, Diana Maria Trasca, George-Alin Stoica, Niculescu Stefan Adrian, Niculescu Elena Carmen, and Cristina Elena Singer. Targeted biologic therapies in severe asthma: mechanisms, biomarkers, and clinical applications. Pharmaceuticals, 18:1021, Jul 2025. URL: https://doi.org/10.3390/ph18071021, doi:10.3390/ph18071021. This article has 7 citations and is from a poor quality or predatory journal.

  9. (massey2021recentadvancesin pages 4-6): Oliver Massey and Cenk Suphioglu. Recent advances in the inhibition of the il-4 cytokine pathway for the treatment of allergen-induced asthma. International Journal of Molecular Sciences, 22:13655, Dec 2021. URL: https://doi.org/10.3390/ijms222413655, doi:10.3390/ijms222413655. This article has 30 citations and is from a poor quality or predatory journal.

Citations

  1. thomas2023designofglycoengineered pages 28-31
  2. wong2025theroleof pages 11-13
  3. nakagome2024thepossibleroles pages 5-7
  4. ameer2025exploringdupilumabfor pages 2-3
  5. varut2025targetedbiologictherapies pages 11-13
  6. reza2025inflammationinasthma pages 14-16
  7. reza2025inflammationinasthma pages 7-8
  8. reza2025inflammationinasthma pages 13-14
  9. massey2021recentadvancesin pages 4-6
  10. https://doi.org/10.1021/acsomega.3c00726,
  11. https://doi.org/10.37349/ei.2025.1003183,
  12. https://doi.org/10.3390/biomedicines13061342,
  13. https://doi.org/10.3390/biom14050546,
  14. https://doi.org/10.3389/fphar.2025.1631321,
  15. https://doi.org/10.3389/fimmu.2024.1356298,
  16. https://doi.org/10.1021/acsomega.3c00726;
  17. https://doi.org/10.3390/biom14050546;
  18. https://doi.org/10.3389/fimmu.2024.1356298;
  19. https://doi.org/10.37349/ei.2025.1003183;
  20. https://doi.org/10.3390/biomedicines13061342;
  21. https://doi.org/10.3389/fphar.2025.1631321;
  22. https://doi.org/10.3390/ph18071021,
  23. https://doi.org/10.3390/ijms222413655,

📄 View Raw YAML

id: P05112
gene_symbol: IL4
product_type: PROTEIN
status: COMPLETE
taxon:
  id: NCBITaxon:9606
  label: Homo sapiens
description: 'Interleukin-4 (IL-4) is a secreted four-helix bundle cytokine of the
  IL-4/IL-13 family, produced primarily by Th2 cells, basophils, mast cells, eosinophils,
  and group 2 innate lymphoid cells (ILC2s). It functions as the master regulator
  of type 2 immunity by binding the IL-4 receptor alpha chain (IL4RA) and signaling
  through two receptor complexes: the type I complex (IL4RA/IL2RG) on hematopoietic
  cells, and the type II complex (IL4RA/IL13RA1) on non-hematopoietic and some hematopoietic
  cells. IL-4 signals canonically through JAK1/JAK3-STAT6, leading to GATA3 induction
  that drives Th2 differentiation, B cell class switch recombination to IgE and IgG4,
  MHC class II upregulation on B cells, and M2 macrophage polarization. IL-4 also
  activates IRS-2/PI3K pathways contributing to cell survival and proliferation. It
  is a central mediator of allergic inflammation, anti-helminth defense, and various
  immune regulatory processes. The protein has three disulfide bonds (Cys3-Cys127,
  Cys24-Cys65, Cys46-Cys99) and one N-glycosylation site (Asn62). An alternatively
  spliced isoform (IL-4delta2) lacking exon 2 acts as a natural antagonist.'
alternative_products:
- name: 1 (Long)
  id: P05112-1
- name: 2 (Short, IL-4delta2)
  id: P05112-2
  sequence_note: VSP_002672
existing_annotations:
- term:
    id: GO:0035771
    label: interleukin-4-mediated signaling pathway
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  review:
    summary: IL-4 is the defining ligand of the IL-4-mediated signaling pathway. It
      binds IL4RA to initiate JAK/STAT6 signaling cascades that drive Th2 differentiation,
      IgE class switching, and other downstream effects. This is a core biological
      process for IL-4.
    action: ACCEPT
    reason: This is the most specific and appropriate BP term for IL-4 as the initiating
      ligand of this pathway. The IBA annotation is phylogenetically well-supported
      and represents the central biological role of the protein. Extensively documented
      in the deep research and UniProt function annotation.
    supported_by:
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: IL-4 signals via two receptor complexes...type I (IL-4R-alpha/gamma-c)
        largely on hematopoietic cells and type II (IL-4R-alpha/IL-13R-alpha1) on
        many non-hematopoietic cells. JAK-STAT is canonical...converging on STAT6
    - reference_id: PMID:12574355
      supporting_text: IL-4-dependent AID induction was inhibited by a dominant-negative
        STAT6, indicating that IL-4 induced AID expression via the Janus kinase (JAK)/STAT6
        signaling pathway
- term:
    id: GO:0045893
    label: positive regulation of DNA-templated transcription
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  review:
    summary: IL-4 signaling via STAT6 activates transcription of numerous target genes
      including GATA3, germline Ig epsilon transcripts, CD23, and MHC class II genes.
      This is a well-established downstream consequence of IL-4 signaling.
    action: ACCEPT
    reason: IL-4 is well-documented as a transcriptional activator through STAT6-mediated
      signaling. The IBA annotation is broadly correct and represents a core downstream
      activity. This is a general term but appropriate for a cytokine with pleiotropic
      transcriptional effects.
    supported_by:
    - reference_id: PMID:12574355
      supporting_text: IL-4 was able to induce AID expression in human primary B cells
        and B cell lines, and IL-4-induced AID expression was further enhanced by
        CD40 signaling
    - reference_id: PMID:20554961
      supporting_text: IL-4 promotes Th2 development by inducing the expression of
        the GATA3 transcription factor
- term:
    id: GO:0050776
    label: regulation of immune response
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  review:
    summary: IL-4 is a major immunoregulatory cytokine that shapes adaptive immune
      responses by driving Th2 polarization, B cell activation and class switching,
      and M2 macrophage polarization, while simultaneously suppressing Th1 responses.
    action: ACCEPT
    reason: This is a broad but accurate term for IL-4. As a key immunoregulatory
      cytokine, IL-4 fundamentally regulates immune responses. The IBA annotation
      is well-supported. While more specific terms exist and are also annotated, this
      general term appropriately captures the broad immunoregulatory role.
    supported_by:
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: IL-4 is a central driver of type-2 endotypes (eosinophilic/allergic)
        across airway and barrier diseases
- term:
    id: GO:0050728
    label: negative regulation of inflammatory response
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  review:
    summary: IL-4 has well-documented anti-inflammatory properties, particularly in
      suppressing pro-inflammatory Th1/M1 macrophage responses, inhibiting TNF-alpha
      production, and promoting M2 (anti-inflammatory) macrophage polarization. This
      is a core function of IL-4 in immune regulation.
    action: ACCEPT
    reason: IL-4 is a canonical anti-inflammatory cytokine that promotes M2 macrophage
      polarization and suppresses pro-inflammatory cytokine production. The IBA annotation
      is phylogenetically well-supported and consistent with extensive experimental
      evidence.
    supported_by:
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: IL-4 drives...alternative (M2) macrophage activation
- term:
    id: GO:0005125
    label: cytokine activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000043
  review:
    summary: IL-4 is by definition a cytokine - a secreted signaling molecule that
      modulates immune cell behavior. This is the most fundamental molecular function
      classification for IL-4.
    action: ACCEPT
    reason: IL-4 is unambiguously a cytokine. The IEA annotation from UniProt keyword
      mapping is correct and consistent with the IDA annotation for the same term.
      This broad MF term is appropriate alongside the more specific GO:0005136 (interleukin-4
      receptor binding).
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Cytokine secreted primarily by mast cells, T-cells, eosinophils,
        and basophils that plays a role in regulating antibody production, hematopoiesis
        and inflammation
- term:
    id: GO:0005126
    label: cytokine receptor binding
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  review:
    summary: IL-4 binds cytokine receptors (IL4RA, IL13RA1) as part of its signaling
      mechanism. This is a parent term of the more specific GO:0005136 (interleukin-4
      receptor binding).
    action: ACCEPT
    reason: This is a correct but less specific parent term. Since the more specific
      GO:0005136 is also annotated, this IEA annotation is redundant but not incorrect.
      Acceptable as an IEA capturing the broader category.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Upon binding to IL4, IL4R receptor dimerizes either with the
        common IL2R gamma chain/IL2RG...or with the IL13RA1
- term:
    id: GO:0005136
    label: interleukin-4 receptor binding
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  review:
    summary: IL-4 specifically binds the IL-4 receptor alpha chain (IL4RA) at its
      site I interface (helices A-C, key residues Glu9/Arg88). This is the most specific
      and informative MF term for IL-4.
    action: ACCEPT
    reason: This is the core molecular function of IL-4 as a ligand. The IEA annotation
      from InterPro domain mapping is correct and supported by extensive structural
      and biochemical data, including crystal structures of the IL-4/IL4RA complex.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Interacts with IL4R...Interacts with IL13RA1
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: structure-function mapping identifies site I on helices A-C
        as the IL-4R-alpha interface (key residues Glu9, Arg88)
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  review:
    summary: IL-4 is a secreted cytokine that functions in the extracellular region.
      UniProt annotates it as Secreted.
    action: ACCEPT
    reason: IL-4 is a secreted protein with a signal peptide (residues 1-24). The
      extracellular region localization is correct and well-established. This is broader
      than GO:0005615 (extracellular space) but acceptable as an IEA annotation.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: 'SUBCELLULAR LOCATION: Secreted'
- term:
    id: GO:0005615
    label: extracellular space
  evidence_type: IEA
  original_reference_id: GO_REF:0000043
  review:
    summary: IL-4 is secreted into the extracellular space where it functions as a
      paracrine/ autocrine signaling molecule.
    action: ACCEPT
    reason: Correct IEA annotation consistent with the IDA evidence for the same term.
      IL-4 is a secreted cytokine that acts in the extracellular space.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: 'SUBCELLULAR LOCATION: Secreted'
- term:
    id: GO:0006955
    label: immune response
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  review:
    summary: IL-4 is a key mediator of immune responses, particularly type 2 immunity.
      This is a very broad BP term.
    action: ACCEPT
    reason: This is a very general but correct IEA annotation. IL-4 is fundamentally
      an immune response mediator. More specific terms are also annotated. Acceptable
      as a broad IEA classification.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Cytokine secreted primarily by mast cells, T-cells, eosinophils,
        and basophils that plays a role in regulating antibody production, hematopoiesis
        and inflammation, and the development of effector T-cell responses
- term:
    id: GO:0008083
    label: growth factor activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  review:
    summary: IL-4 was historically known as B-cell stimulatory factor 1 (BSF-1) and
      promotes proliferation of B and T cells. However, its primary identity is as
      a cytokine rather than a classical growth factor.
    action: KEEP_AS_NON_CORE
    reason: While IL-4 does promote cell proliferation (B cells, T cells), its primary
      molecular function is better described as cytokine activity (GO:0005125) and
      IL-4 receptor binding (GO:0005136). Growth factor activity is a secondary characterization.
      The UniProt keyword mapping that generated this annotation reflects the historical
      BSF-1 naming but is not the most informative descriptor.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: AltName...B-cell stimulatory factor 1; Short=BSF-1
- term:
    id: GO:0010628
    label: positive regulation of gene expression
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  review:
    summary: IL-4 upregulates expression of numerous genes through STAT6 signaling,
      including GATA3, AID, germline Ig epsilon transcripts, CD23, and MHC class II
      molecules.
    action: ACCEPT
    reason: This is a broad but correct IEA annotation from ARBA. IL-4 is a potent
      inducer of gene expression in immune cells. More specific transcription regulation
      terms are also annotated.
    supported_by:
    - reference_id: PMID:12574355
      supporting_text: IL-4 was able to induce AID expression in human primary B cells
        and B cell lines
- term:
    id: GO:0030335
    label: positive regulation of cell migration
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  review:
    summary: IL-4 can promote cell migration in certain contexts, including macrophage
      and tumor cell migration. This is a secondary, context-dependent effect.
    action: KEEP_AS_NON_CORE
    reason: While there is evidence that IL-4 can regulate cell migration, this is
      not a core function of the cytokine. It represents a pleiotropic downstream
      effect rather than the primary evolved function. The ARBA-generated IEA annotation
      is acceptable but should not be considered a defining function.
- term:
    id: GO:0042113
    label: B cell activation
  evidence_type: IEA
  original_reference_id: GO_REF:0000043
  review:
    summary: IL-4 is a major B cell activating factor that induces B cell proliferation,
      class switching to IgE and IgG, and upregulation of MHC class II and CD23. This
      is one of the historically defining functions of IL-4 (originally named B-cell
      stimulatory factor 1).
    action: ACCEPT
    reason: B cell activation is a core function of IL-4. The IEA from UniProt keyword
      mapping accurately reflects that IL-4 was originally identified as BSF-1 precisely
      because of its B cell activating properties.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Induces the expression of class II MHC molecules on resting
        B-cells. Enhances both secretion and cell surface expression of IgE and IgG1
- term:
    id: GO:0045321
    label: leukocyte activation
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  review:
    summary: IL-4 activates multiple leukocyte types including B cells, T cells, macrophages,
      and dendritic cells. This is a broad parent term.
    action: ACCEPT
    reason: This broad IEA term is correct. IL-4 activates multiple leukocyte populations.
      More specific child terms (B cell activation, T cell activation, macrophage
      activation) are also annotated.
- term:
    id: GO:0051239
    label: regulation of multicellular organismal process
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  review:
    summary: IL-4 regulates immune processes at the organismal level, affecting allergic
      responses, anti-helminth immunity, and tissue remodeling.
    action: MARK_AS_OVER_ANNOTATED
    reason: This is an extremely broad and uninformative term. While technically true,
      it provides no useful information about IL-4 function. More specific terms are
      available and annotated. The ARBA machine learning annotation is too general
      to be informative.
- term:
    id: GO:0080090
    label: regulation of primary metabolic process
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  review:
    summary: IL-4 can regulate metabolic processes in target cells, but this is an
      extremely broad and uninformative annotation.
    action: MARK_AS_OVER_ANNOTATED
    reason: This term is far too general to be informative for IL-4 annotation. While
      IL-4 signaling does affect metabolic processes in target cells, this ARBA-generated
      term does not convey any meaningful biological insight about the protein.
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:10219247
  review:
    summary: PMID:10219247 reports the crystal structure of IL-4 in complex with IL4RA
      at 2.30 angstroms resolution, demonstrating direct protein-protein interaction.
      The WITH column specifies UniProtKB:P24394 (IL4R).
    action: MODIFY
    reason: The protein binding annotation is uninformative. The interaction demonstrated
      in PMID:10219247 is specifically IL-4 binding to the IL-4 receptor alpha chain,
      which is better captured by GO:0005136 (interleukin-4 receptor binding), which
      is already annotated via IEA, TAS, and IDA evidence.
    proposed_replacement_terms:
    - id: GO:0005136
      label: interleukin-4 receptor binding
    supported_by:
    - reference_id: PMID:10219247
      supporting_text: IL-4 binds with high affinity and specificity to the ectodomain
        of the IL-4 receptor alpha chain (IL4-BP)
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: X-RAY CRYSTALLOGRAPHY (2.30 ANGSTROMS) OF 25-153 IN COMPLEX
        WITH IL4R...INTERACTION WITH IL4R
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:18243101
  review:
    summary: PMID:18243101 reports the crystal structure of IL-4 in complex with IL13RA1
      and IL4RA, elucidating the molecular basis of cytokine receptor pleiotropy in
      the IL-4/IL-13 system. The GOA TSV shows two separate annotations from this
      PMID, one with IL4R (P24394) and one with IL13RA1 (P78552).
    action: MODIFY
    reason: The generic protein binding term is uninformative. The interaction with
      IL4RA is better captured by GO:0005136, and the interaction with IL13RA1 represents
      a component of the type II receptor complex formation.
    proposed_replacement_terms:
    - id: GO:0005136
      label: interleukin-4 receptor binding
    supported_by:
    - reference_id: PMID:18243101
      supporting_text: Here we present the crystal structures of the complete set
        of type I (IL-4R alpha/gamma(c)/IL-4) and type II (IL-4R alpha/IL-13R alpha1/IL-4,
        IL-4R alpha/IL-13R alpha1/IL-13) ternary signaling complexes
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: X-RAY CRYSTALLOGRAPHY (2.93 ANGSTROMS) OF 25-153...INTERACTION
        WITH IL13RA1, AND FUNCTION
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:23597562
  review:
    summary: PMID:23597562 is about a small-molecule FGFR inhibitor (SSR128129E) and
      its anti-tumor angiogenesis effects. The WITH column specifies IL4R (P24394).
      This annotation likely derives from an IntAct high-throughput dataset associated
      with this publication where IL4-IL4R interaction was detected.
    action: MODIFY
    reason: The IL-4/IL-4R interaction is well-established but the generic protein
      binding term is uninformative. If the interaction is genuine, it is better captured
      by GO:0005136 (interleukin-4 receptor binding). Additionally, the primary publication
      focus is FGFR biology, making the provenance of this specific annotation unclear.
    proposed_replacement_terms:
    - id: GO:0005136
      label: interleukin-4 receptor binding
    supported_by:
    - reference_id: PMID:23597562
      supporting_text: we report the pharmacologic characterization of the chemical
        SSR128129E (SSR), which inhibits fibroblast growth factor receptor (FGFR)
        signaling
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:8266078
  review:
    summary: PMID:8266078 demonstrates that the IL-2 receptor gamma chain is a functional
      component of the IL-4 receptor, showing IL-4 binding and signaling through the
      IL4RA/IL2RG complex.
    action: MODIFY
    reason: As with the other protein binding annotations for IL-4, the interaction
      with IL4R is better captured by the specific term GO:0005136 (interleukin-4
      receptor binding). The generic protein binding term is uninformative.
    proposed_replacement_terms:
    - id: GO:0005136
      label: interleukin-4 receptor binding
    supported_by:
    - reference_id: PMID:8266078
      supporting_text: IL-2R gamma was demonstrated to be a component of the IL-4
        receptor on the basis of chemical cross-linking data, the ability of IL-2R
        gamma to augment IL-4 binding affinity, and the requirement for IL-2R gamma
        in IL-4-mediated phosphorylation of insulin receptor substrate-1
- term:
    id: GO:0007259
    label: cell surface receptor signaling pathway via JAK-STAT
  evidence_type: IDA
  original_reference_id: PMID:23103943
  review:
    summary: IL-4 signals through JAK1/JAK3 (type I receptor) and JAK1/TYK2 (type
      II receptor) to activate STAT6, and to a lesser extent STAT3. This annotation
      captures the canonical signaling mechanism.
    action: ACCEPT
    reason: JAK-STAT signaling is the primary intracellular signaling pathway activated
      by IL-4. The IDA annotation from ComplexPortal is well-supported by extensive
      literature.
    supported_by:
    - reference_id: PMID:23103943
      supporting_text: Formation of the IL-4/IL-4Rα/γc or IL-4/IL-4Rα/IL-13Rα1 complex
        on the cell surface activates intracellular signaling pathways including the
        Jak-STAT and the PI3K/Akt pathways
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Engagement of both types of receptors initiates JAK3 and to
        a lower extend JAK1 phosphorylation leading to activation of the signal transducer
        and activator of transcription 6/STAT6
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: JAK-STAT is canonical...type I (primarily JAK1/JAK3) and type
        II (JAK2/TYK2 reported), converging on STAT6
- term:
    id: GO:0035771
    label: interleukin-4-mediated signaling pathway
  evidence_type: NAS
  original_reference_id: PMID:18243101
  review:
    summary: PMID:18243101 elucidated the structural basis for cytokine receptor pleiotropy
      in the IL-4/IL-13 system, providing mechanistic insight into IL-4 signaling
      through both type I and type II receptor complexes.
    action: ACCEPT
    reason: This NAS annotation is well-supported. The referenced paper provides definitive
      structural evidence for IL-4 receptor complex assembly, which is the initiating
      event of the IL-4-mediated signaling pathway. Duplicate of the IBA annotation
      but with different evidence, which is acceptable.
    supported_by:
    - reference_id: PMID:18243101
      supporting_text: Here we present the crystal structures of the complete set
        of type I (IL-4R alpha/gamma(c)/IL-4) and type II (IL-4R alpha/IL-13R alpha1/IL-4,
        IL-4R alpha/IL-13R alpha1/IL-13) ternary signaling complexes
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: X-RAY CRYSTALLOGRAPHY...OF 25-153, DISULFIDE BONDS, INTERACTION
        WITH IL13RA1, AND FUNCTION
- term:
    id: GO:0042531
    label: positive regulation of tyrosine phosphorylation of STAT protein
  evidence_type: NAS
  original_reference_id: PMID:18243101
  review:
    summary: IL-4 receptor engagement leads to JAK-mediated phosphorylation of STAT6
      (at Y641) and STAT3 (at Y705). This is a direct mechanistic consequence of IL-4
      signaling.
    action: ACCEPT
    reason: STAT6 tyrosine phosphorylation is the key signaling event downstream of
      IL-4 receptor activation. The NAS annotation from ComplexPortal accurately captures
      this core signaling mechanism. The Reactome pathway also documents JAK1 phosphorylation
      of STAT3 and STAT6.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Engagement of both types of receptors initiates JAK3 and to
        a lower extend JAK1 phosphorylation leading to activation of the signal transducer
        and activator of transcription 6/STAT6
    - reference_id: PMID:12574355
      supporting_text: IL-4-dependent AID induction was inhibited by a dominant-negative
        STAT6, indicating that IL-4 induced AID expression via the Janus kinase (JAK)/STAT6
        signaling pathway
- term:
    id: GO:1902107
    label: positive regulation of leukocyte differentiation
  evidence_type: NAS
  original_reference_id: PMID:23103943
  review:
    summary: IL-4 drives differentiation of multiple leukocyte lineages including
      Th2 cells from naive T cells, dendritic cells from monocytes, and M2 macrophages
      from monocytes/ macrophages.
    action: ACCEPT
    reason: This is a well-supported annotation. IL-4 is a key driver of leukocyte
      differentiation programs, particularly Th2 differentiation and dendritic cell
      differentiation. The NAS evidence from ComplexPortal is consistent with extensive
      experimental data.
    supported_by:
    - reference_id: PMID:23103943
      supporting_text: Cytokines dimerize their receptors, with the binding of the
        'second chain' triggering signaling
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: IL-4 drives Th2 differentiation (via STAT6->GATA3), B-cell
        proliferation and class-switch recombination to IgE, and alternative (M2)
        macrophage activation
- term:
    id: GO:0007259
    label: cell surface receptor signaling pathway via JAK-STAT
  evidence_type: IGI
  original_reference_id: PMID:12574355
  review:
    summary: PMID:12574355 demonstrates that IL-4 induces AID expression via JAK/STAT6
      signaling, and that CD45 negatively regulates this pathway by acting as a JAK
      phosphatase. The IGI annotation with STAT6 (P42226) provides genetic interaction
      evidence.
    action: ACCEPT
    reason: The paper directly demonstrates IL-4 activates JAK/STAT6 signaling using
      dominant- negative STAT6 experiments. The genetic interaction with STAT6 provides
      strong evidence for this pathway annotation.
    supported_by:
    - reference_id: PMID:12574355
      supporting_text: IL-4-dependent AID induction was inhibited by a dominant-negative
        STAT6, indicating that IL-4 induced AID expression via the Janus kinase (JAK)/STAT6
        signaling pathway
- term:
    id: GO:0035771
    label: interleukin-4-mediated signaling pathway
  evidence_type: IDA
  original_reference_id: PMID:12574355
  review:
    summary: PMID:12574355 directly demonstrates IL-4 signaling through JAK/STAT6
      in the context of AID gene induction in B cells.
    action: ACCEPT
    reason: The paper provides direct experimental evidence for IL-4-mediated signaling
      pathway activation using IL-4 stimulation of B cells and demonstrating JAK-dependent
      STAT6 activation.
    supported_by:
    - reference_id: PMID:12574355
      supporting_text: IL-4 was able to induce AID expression in human primary B cells
        and B cell lines...IL-4-induced AID expression was further enhanced by CD40
        signaling
- term:
    id: GO:0045944
    label: positive regulation of transcription by RNA polymerase II
  evidence_type: IGI
  original_reference_id: PMID:12574355
  review:
    summary: PMID:12574355 shows IL-4 induces AID gene transcription through STAT6-dependent
      mechanisms. The IGI evidence includes interactions with CD45 (P08575), CD40
      (P29965), and STAT6 (P42226).
    action: ACCEPT
    reason: The paper demonstrates IL-4 positively regulates transcription of the
      AID gene in B cells, with genetic interaction evidence from STAT6 dominant-negative,
      CD45, and CD40 experiments.
    supported_by:
    - reference_id: PMID:12574355
      supporting_text: IL-4 was able to induce AID expression in human primary B cells
        and B cell lines, and IL-4-induced AID expression was further enhanced by
        CD40 signaling
- term:
    id: GO:0005125
    label: cytokine activity
  evidence_type: IDA
  original_reference_id: PMID:10219247
  review:
    summary: PMID:10219247 reports the crystal structure of the IL-4/IL4RA complex
      and characterizes the receptor binding interface, providing direct structural
      evidence for IL-4's cytokine activity.
    action: ACCEPT
    reason: This IDA annotation is well-supported. The referenced paper demonstrates
      direct IL-4/receptor interaction through structural analysis, confirming IL-4
      functions as a cytokine that binds and activates its cognate receptor.
    supported_by:
    - reference_id: PMID:10219247
      supporting_text: Interleukin-4 (IL-4) is a principal regulatory cytokine during
        an immune response and a crucial determinant for allergy and asthma
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Crystal structure of the interleukin-4/receptor alpha chain
        complex reveals a mosaic binding interface
- term:
    id: GO:0005615
    label: extracellular space
  evidence_type: IDA
  original_reference_id: PMID:3279117
  review:
    summary: PMID:3279117 demonstrates that exogenous recombinant IL-4 acts on monocytes
      in culture, confirming its activity as a secreted extracellular protein. The
      paper shows IL-4 modulates monocyte phenotype and function when added to culture
      medium.
    action: ACCEPT
    reason: IL-4 is a secreted cytokine with a signal peptide. Its localization to
      the extracellular space is unambiguous. The paper demonstrates IL-4 acting as
      an extracellular factor on monocytes.
    supported_by:
    - reference_id: PMID:3279117
      supporting_text: Highly purified peripheral blood monocytes were cultured in
        the presence of rIL-4
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: 'SUBCELLULAR LOCATION: Secreted'
- term:
    id: GO:0035771
    label: interleukin-4-mediated signaling pathway
  evidence_type: IDA
  original_reference_id: PMID:10219247
  review:
    summary: PMID:10219247 provides structural evidence for IL-4 receptor complex
      formation, the initiating event of the IL-4-mediated signaling pathway.
    action: ACCEPT
    reason: The crystal structure of IL-4 bound to IL4RA demonstrates the molecular
      basis of IL-4 signaling initiation. This IDA annotation is well-supported and
      consistent with other annotations for the same GO term.
    supported_by:
    - reference_id: PMID:10219247
      supporting_text: this intermediate complex recruits the common gamma chain (gamma
        c), thereby initiating transmembrane signaling
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Crystal structure of the interleukin-4/receptor alpha chain
        complex reveals a mosaic binding interface
- term:
    id: GO:0000122
    label: negative regulation of transcription by RNA polymerase II
  evidence_type: IDA
  original_reference_id: PMID:11967989
  review:
    summary: PMID:11967989 shows that IL-4 attenuates TGF-beta-stimulated induction
      of CTGF mRNA expression in human lung fibroblasts, through interference with
      TGF-beta-induced transcriptional activation of the CTGF gene.
    action: KEEP_AS_NON_CORE
    reason: The paper demonstrates IL-4 can negatively regulate specific gene transcription
      (CTGF), but this is a context-specific effect in lung fibroblasts rather than
      a core function of IL-4. IL-4's primary role is transcriptional activation of
      immune genes, not transcriptional repression.
    supported_by:
    - reference_id: PMID:11967989
      supporting_text: IL-4 attenuated the TGF-beta-stimulated induction of CTGF mRNA
        expression by 50%...IL-4 interfered with the TGF-beta-induced transcriptional
        activation of the CTGF gene
- term:
    id: GO:1903845
    label: negative regulation of cellular response to transforming growth factor
      beta stimulus
  evidence_type: IDA
  original_reference_id: PMID:11967989
  review:
    summary: PMID:11967989 directly demonstrates that IL-4 antagonizes TGF-beta signaling
      in lung fibroblasts by attenuating TGF-beta-induced CTGF expression.
    action: KEEP_AS_NON_CORE
    reason: While the paper provides direct evidence for this annotation, IL-4's antagonism
      of TGF-beta signaling in fibroblasts is a tissue-specific context-dependent
      effect, not a core function of the cytokine. This represents pleiotropic activity.
    supported_by:
    - reference_id: PMID:11967989
      supporting_text: IL-4 attenuated the TGF-beta-stimulated induction of CTGF mRNA
        expression by 50%. This effect was selective because IL-4 did not affect fibronectin
        or alpha1(I) collagen mRNA expression induced by TGF-beta
- term:
    id: GO:0008284
    label: positive regulation of cell population proliferation
  evidence_type: IGI
  original_reference_id: PMID:31432141
  review:
    summary: PMID:31432141 identifies IL-4 as a direct target of miR-320a in trophoblast
      cells (HTR-8/SVneo). Rescue experiments demonstrate that IL-4 overexpression
      partially reverses the anti-proliferative effect of miR-320a on trophoblast
      cells (MTT assay). The IGI evidence involves miR-320a (RNAcentral:URS00003CF1AD_9606)
      with acts_upstream_of_or_within qualifier. The proliferation effect is in trophoblast
      cells in the context of preeclampsia.
    action: KEEP_AS_NON_CORE
    reason: The paper provides evidence that IL-4 promotes trophoblast cell proliferation
      in the preeclampsia context. While IL-4 also promotes B and T cell proliferation
      as a core function (annotated separately via ISS), this specific annotation
      reflects a non-immune cell proliferation effect that is not a core function
      of the cytokine.
    supported_by:
    - reference_id: PMID:31432141
      supporting_text: restoring the expression level of IL-4 partially decreased
        the inhibitory effect of miR-320a overexpression on HTR-8/SVneo cell proliferation
    - reference_id: PMID:31432141
      supporting_text: Collectively, the present data suggested that IL-4 was a functional
        target gene of miR-320a, and miR-320a upregulation inhibited the proliferation
        and invasion of HTR-8/SVneo cells by directly targeting IL-4
- term:
    id: GO:0030335
    label: positive regulation of cell migration
  evidence_type: IGI
  original_reference_id: PMID:31432141
  review:
    summary: PMID:31432141 studies miR-320a in preeclampsia trophoblast cells (HTR-8/SVneo).
      IL-4 is identified as a direct target of miR-320a. Rescue experiments show that
      overexpression of IL-4 partially reverses the inhibitory effect of miR-320a
      on trophoblast cell invasion (Transwell assay). The IGI evidence involves miR-320a
      (RNAcentral:URS00003CF1AD_9606) as the interacting partner, with acts_upstream_of_or_within
      qualifier. The cell migration/invasion effect is in trophoblast cells, not immune
      cells.
    action: KEEP_AS_NON_CORE
    reason: The paper provides evidence that IL-4 promotes trophoblast cell invasion
      in the context of preeclampsia, which is consistent with the IEA annotation
      for the same term that was already marked KEEP_AS_NON_CORE. Cell migration promotion
      is not a core immune function of IL-4 but represents a pleiotropic effect in
      non-immune cell types.
    supported_by:
    - reference_id: PMID:31432141
      supporting_text: overexpression of IL-4 in HTR-8/SVneo cells reduced the inhibitory
        effect of miR-320a overexpression on cell invasion
    - reference_id: PMID:31432141
      supporting_text: miR-320a upregulation inhibited the proliferation and invasion
        of HTR-8/SVneo cells by directly targeting IL-4
- term:
    id: GO:0032733
    label: positive regulation of interleukin-10 production
  evidence_type: IGI
  original_reference_id: PMID:30634164
  review:
    summary: PMID:30634164 studies macrophage polarization and shows that M2 macrophages
      (induced by IL-4 and IL-13) express higher levels of IL-10 than M1 macrophages.
      The IGI evidence involves IL-13 (P35225), reflecting the cooperative use of
      IL-4 and IL-13 in M2 polarization protocols.
    action: ACCEPT
    reason: The paper demonstrates that IL-4/IL-13-induced M2 macrophages express
      higher IL-10 levels than M1 macrophages, supporting IL-4's role in promoting
      IL-10 production. This is consistent with IL-4's well-established anti-inflammatory
      M2-polarizing function and the known IL-10 production by M2 macrophages.
    supported_by:
    - reference_id: PMID:30634164
      supporting_text: M1 macrophages express higher levels of IL-16 than M2 macrophages
        but express lower levels of IL-10 and mir-145 than M2 cells
- term:
    id: GO:0042116
    label: macrophage activation
  evidence_type: IGI
  original_reference_id: PMID:30634164
  review:
    summary: PMID:30634164 uses IL-4 and IL-13 to induce M2 macrophage polarization
      from THP-1 monocytes. IL-4 is a canonical driver of alternative macrophage activation
      (M2 polarization). The IGI evidence with IL-13 (P35225) reflects the cooperative
      use of these cytokines in M2 polarization.
    action: ACCEPT
    reason: M2 macrophage activation by IL-4 is one of its best-established functions.
      The paper directly uses IL-4 in the M2 polarization protocol. This is extensively
      documented in the deep research and is a core function of IL-4 in innate immunity.
    supported_by:
    - reference_id: PMID:30634164
      supporting_text: THP-1 cells were induced by IL-4 and IL-13 following PMA incubation
        (M2 polarized macrophages) or induced by IFN-gamma and LPS (M1 classical macrophage
        activation)
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: IL-4 drives...alternative (M2) macrophage activation; IL-13
        overlaps but acts more directly on structural cells
- term:
    id: GO:0050728
    label: negative regulation of inflammatory response
  evidence_type: IGI
  original_reference_id: PMID:30634164
  review:
    summary: PMID:30634164 demonstrates that IL-4/IL-13-induced M2 macrophages have
      an anti-inflammatory profile with high IL-10 and low pro-inflammatory cytokines.
      IL-4 suppresses inflammatory responses through M2 macrophage polarization. The
      IGI evidence with IL-13 (P35225) reflects cooperative anti-inflammatory signaling.
    action: ACCEPT
    reason: This is a duplicate of the IBA annotation for the same term, with independent
      IGI evidence. The anti-inflammatory role of IL-4 is well-established and represents
      a core function. Duplicate annotations with different evidence codes are acceptable.
    supported_by:
    - reference_id: PMID:30634164
      supporting_text: THP-1 cells were induced by IL-4 and IL-13 following PMA incubation
        (M2 polarized macrophages) or induced by IFN-gamma and LPS (M1 classical macrophage
        activation)
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: IL-4 drives...alternative (M2) macrophage activation
- term:
    id: GO:0010628
    label: positive regulation of gene expression
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 upregulates gene expression in target cells through STAT6-mediated
      transcriptional activation. Transferred from mouse IL-4 (P07750) and rat IL-4
      (P20096).
    action: ACCEPT
    reason: This ISS annotation is well-supported by the conserved function of IL-4
      across mammals. IL-4 is a potent inducer of gene expression through STAT6 signaling.
      The annotation is consistent with the IDA evidence for transcription regulation
      and with the IEA annotation for the same term.
    supported_by:
    - reference_id: PMID:12574355
      supporting_text: IL-4 was able to induce AID expression in human primary B cells
        and B cell lines
- term:
    id: GO:0150076
    label: neuroinflammatory response
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 has been implicated in neuroinflammation, particularly in the context
      of neuroprotection and microglial polarization. Transferred from mouse IL-4
      (P20096) by ARUK-UCL curators.
    action: KEEP_AS_NON_CORE
    reason: While IL-4 has documented roles in neuroinflammation (primarily anti-inflammatory/
      neuroprotective effects via M2 microglial polarization), this is a tissue-specific
      context-dependent activity, not a core immune function of IL-4. The ISS from
      mouse is reasonable but this represents a specialized function.
- term:
    id: GO:0032720
    label: negative regulation of tumor necrosis factor production
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 suppresses TNF-alpha production, particularly in macrophages, as
      part of its anti-inflammatory and M2-polarizing activity. Transferred from mouse
      IL-4 (P07750).
    action: ACCEPT
    reason: Suppression of TNF-alpha production is a well-established function of
      IL-4 in the context of its anti-inflammatory M2 macrophage polarization program.
      The ISS from mouse is appropriate given conserved IL-4 function.
    supported_by:
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: IL-4 drives...alternative (M2) macrophage activation
- term:
    id: GO:1901857
    label: positive regulation of cellular respiration
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 has been reported to promote mitochondrial respiration in macrophages
      as part of M2 metabolic reprogramming. Transferred from mouse IL-4 (P07750)
      by ARUK-UCL.
    action: KEEP_AS_NON_CORE
    reason: While IL-4-driven M2 macrophage polarization involves metabolic reprogramming
      toward oxidative phosphorylation, this metabolic effect is a downstream consequence
      of M2 polarization rather than a core function of IL-4 itself. The annotation
      is not incorrect but represents a specialized downstream effect.
- term:
    id: GO:2001171
    label: positive regulation of ATP biosynthetic process
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: Related to the metabolic reprogramming of M2 macrophages toward oxidative
      phosphorylation. Transferred from mouse IL-4 (P07750) by ARUK-UCL.
    action: KEEP_AS_NON_CORE
    reason: This is a highly specific metabolic effect that is downstream of M2 macrophage
      polarization. Not a core function of IL-4 as a cytokine. Over-specific annotation
      of a downstream metabolic consequence.
- term:
    id: GO:0150079
    label: negative regulation of neuroinflammatory response
  evidence_type: IC
  original_reference_id: GO_REF:0000111
  review:
    summary: IC annotation inferred from ISS evidence. IL-4 has anti-inflammatory
      effects in the CNS, promoting M2 microglial polarization and suppressing neuroinflammation.
    action: KEEP_AS_NON_CORE
    reason: While IL-4 has documented neuroprotective and anti-neuroinflammatory effects,
      these are tissue-specific activities rather than core immune functions. The
      IC evidence based on ISS is reasonable but this represents a specialized function.
- term:
    id: GO:0048260
    label: positive regulation of receptor-mediated endocytosis
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 may promote receptor-mediated endocytosis in certain cell types,
      possibly related to amyloid-beta clearance by microglia. Transferred from mouse
      IL-4 (P07750 and P20096) by ARUK-UCL.
    action: KEEP_AS_NON_CORE
    reason: This annotation likely relates to IL-4's role in promoting microglial
      phagocytic clearance of amyloid-beta, which is a very specialized neuroimmune
      function rather than a core IL-4 activity.
- term:
    id: GO:1900223
    label: positive regulation of amyloid-beta clearance
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 has been reported to promote amyloid-beta clearance by microglia
      in Alzheimer's disease models. Transferred from mouse IL-4 (P07750 and P20096)
      by ARUK-UCL.
    action: KEEP_AS_NON_CORE
    reason: While there is mouse literature supporting IL-4's role in promoting amyloid-beta
      clearance, this is a highly specialized neuroimmune function that is far from
      the core evolved function of IL-4 as an immune cytokine. The ISS transfer is
      reasonable but this represents a tissue-specific activity.
- term:
    id: GO:0016239
    label: positive regulation of macroautophagy
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 has been reported to stimulate autophagy in dendritic cells. The
      UniProt function annotation notes IL-4 stimulates autophagy by interfering with
      mTORC1 signaling and through RUFY4 induction. Transferred from mouse IL-4 (P07750).
    action: KEEP_AS_NON_CORE
    reason: While UniProt documents this function, autophagy induction is a specialized
      downstream effect of IL-4 signaling rather than a core function. The ISS annotation
      is supported by the UniProt function description.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Stimulates autophagy in dendritic cells by interfering with
        mTORC1 signaling and through the induction of RUFY4
- term:
    id: GO:0120162
    label: positive regulation of cold-induced thermogenesis
  evidence_type: ISS
  original_reference_id: PMID:24906148
  review:
    summary: PMID:24906148 demonstrates that IL-4/IL-13 signaling in macrophages is
      required for cold-induced beige fat biogenesis. Administration of IL-4 to thermoneutral
      mice increases beige fat mass and thermogenic capacity. The ISS is from mouse
      IL-4 (P07750).
    action: KEEP_AS_NON_CORE
    reason: While the paper provides compelling evidence that IL-4 promotes beige
      fat thermogenesis through alternatively activated macrophages, this is a specialized
      metabolic function far removed from IL-4's core immune role.
    supported_by:
    - reference_id: PMID:24906148
      supporting_text: Genetic loss of eosinophils or IL-4/13 signaling impairs cold-induced
        biogenesis of beige fat
    - reference_id: PMID:24906148
      supporting_text: administration of IL-4 to thermoneutral mice increases beige
        fat mass and thermogenic capacity to ameliorate pre-established obesity
- term:
    id: GO:0042110
    label: T cell activation
  evidence_type: IGI
  original_reference_id: PMID:18337562
  review:
    summary: PMID:18337562 is about CCL5-mediated T cell chemotaxis involving mTOR/4E-BP1
      translation initiation. The paper studied CD4+ T cell migration in response
      to CCL5, not IL-4. The IGI evidence involves CD82 (P10747). The connection to
      IL-4 is unclear.
    action: UNDECIDED
    reason: The referenced publication (PMID:18337562) is about CCL5 (RANTES)-mediated
      T cell chemotaxis, not IL-4 function. While IL-4 is known to activate T cells
      (particularly driving Th2 differentiation), this specific annotation appears
      to reference an unrelated paper. The annotation may have been made based on
      a secondary finding or data in the paper, but the primary focus is CCL5.
    supported_by:
    - reference_id: PMID:18337562
      supporting_text: CCL5-mediated T-cell chemotaxis involves the initiation of
        mRNA translation through mTOR/4E-BP1
- term:
    id: GO:0045892
    label: negative regulation of DNA-templated transcription
  evidence_type: IDA
  original_reference_id: PMID:16606666
  review:
    summary: PMID:16606666 demonstrates that IL-4 inhibits B7-H4 (VTCN1) expression
      on tumor macrophages in human ovarian carcinoma. IL-4 negatively regulates B7-H4
      transcription, in contrast to IL-6 and IL-10 which stimulate its expression.
    action: KEEP_AS_NON_CORE
    reason: The paper provides direct evidence that IL-4 negatively regulates B7-H4
      expression on macrophages. This is consistent with the other GO:0045892 annotation
      from PMID:18579517 (also KEEP_AS_NON_CORE) and the GO:0000122 annotation from
      PMID:11967989 for CTGF. IL-4's ability to repress specific genes is a real but
      context-dependent activity, not a core function.
    supported_by:
    - reference_id: PMID:16606666
      supporting_text: granulocyte/macrophage colony-stimulating factor and IL-4,
        which are limited in the tumor microenvironment, inhibit B7-H4 expression
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-6785821
  review:
    summary: Reactome annotation for IL-4 participation in the IL-4/IL-13 signaling
      pathway, specifically the SOCS5/SOCS1 binding to IL4RA reaction. IL-4 is correctly
      placed in the extracellular region.
    action: ACCEPT
    reason: IL-4 is a secreted cytokine in the extracellular region. These Reactome
      TAS annotations correctly reflect IL-4's participation in signaling pathway
      reactions as an extracellular ligand.
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-6786058
  review:
    summary: Reactome annotation for IL-4 signaling - JAK1 binding to IL4R in IL4-bound
      complex.
    action: ACCEPT
    reason: Duplicate CC annotation from Reactome pathway. IL-4 is correctly localized
      to the extracellular region as part of the receptor-ligand complex.
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-6786070
  review:
    summary: Reactome annotation for type II receptor complex assembly (IL-4 complex
      binding IL13RA1/TYK2).
    action: ACCEPT
    reason: Duplicate CC annotation from Reactome pathway. Correct localization.
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-6786072
  review:
    summary: Reactome annotation for STAT3/STAT6 dissociation step in IL-4 signaling.
    action: ACCEPT
    reason: Duplicate CC annotation from Reactome pathway. Correct localization.
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-6786092
  review:
    summary: Reactome annotation for type I receptor complex assembly (IL-4 complex
      binding IL2RG/JAK3).
    action: ACCEPT
    reason: Duplicate CC annotation from Reactome pathway. Correct localization.
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-6786095
  review:
    summary: Reactome annotation for JAK1 phosphorylation of STAT3/STAT6 in IL-4 signaling.
    action: ACCEPT
    reason: Duplicate CC annotation from Reactome pathway. Correct localization.
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-6786096
  review:
    summary: Reactome annotation for phosphorylation of IL4R/IL2RG/JAK1 components.
    action: ACCEPT
    reason: Duplicate CC annotation from Reactome pathway. Correct localization.
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-6786101
  review:
    summary: Reactome annotation for IL-4 binding to IL4R/JAK2.
    action: ACCEPT
    reason: Duplicate CC annotation from Reactome pathway. Correct localization.
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-6786124
  review:
    summary: Reactome annotation for STAT3/STAT6 binding to phosphorylated IL4R.
    action: ACCEPT
    reason: Duplicate CC annotation from Reactome pathway. Correct localization.
- term:
    id: GO:0043011
    label: myeloid dendritic cell differentiation
  evidence_type: IDA
  original_reference_id: PMID:16116184
  review:
    summary: PMID:16116184 studies galectin-9 effects on monocyte-derived dendritic
      cells that were generated using the standard IL-4 + GM-CSF protocol. The paper
      uses IL-4 to differentiate monocytes into immature DCs, which are then matured
      by galectin-9.
    action: ACCEPT
    reason: IL-4 is a well-established driver of dendritic cell differentiation from
      monocytes. The paper directly employs IL-4 in the DC differentiation protocol.
      The IL-4 + GM-CSF system for DC generation is one of the most widely used in
      immunology.
    supported_by:
    - reference_id: PMID:16116184
      supporting_text: Gal-9 had no or little effect on differentiation of human monocytes
        into immature DCs
- term:
    id: GO:1903660
    label: negative regulation of complement-dependent cytotoxicity
  evidence_type: IMP
  original_reference_id: PMID:16034134
  review:
    summary: PMID:16034134 demonstrates that IL-4 and IL-13 induce protection of porcine
      endothelial cells from killing by human complement through PI3K/Akt signaling.
    action: KEEP_AS_NON_CORE
    reason: The paper provides direct evidence that IL-4 protects endothelial cells
      from complement-mediated killing via PI3K/Akt pathway activation. This is a
      specialized cytoprotective effect in the xenotransplantation context, not a
      core immune function of IL-4.
    supported_by:
    - reference_id: PMID:16034134
      supporting_text: porcine EC incubated with IL-4 or IL-13, but not with IL-10
        or IL-11, became protected from killing by complement and apoptosis induced
        by TNF-alpha plus cycloheximide
- term:
    id: GO:2000352
    label: negative regulation of endothelial cell apoptotic process
  evidence_type: IMP
  original_reference_id: PMID:16034134
  review:
    summary: PMID:16034134 demonstrates that IL-4 protects porcine endothelial cells
      from apoptosis induced by TNF-alpha plus cycloheximide through PI3K/Akt signaling.
    action: KEEP_AS_NON_CORE
    reason: The paper provides direct evidence that IL-4 protects endothelial cells
      from apoptosis via PI3K/Akt pathway activation. This represents a cytoprotective
      effect consistent with IL-4's known anti-apoptotic signaling but in a non-immune
      cell context.
    supported_by:
    - reference_id: PMID:16034134
      supporting_text: IL-4 and IL-13 can induce protection of porcine EC against
        killing by apoptosis and human complement through activation of the PI3K/Akt
        signaling pathway
- term:
    id: GO:0010633
    label: negative regulation of epithelial cell migration
  evidence_type: IDA
  original_reference_id: PMID:11698262
  review:
    summary: PMID:11698262 demonstrates that IL-4 and IL-13 decrease wound healing
      and migration in Calu-3 human lung epithelial cells. IL-4 treatment decreased
      cell migration in wound-healing assays on collagen I.
    action: KEEP_AS_NON_CORE
    reason: The paper provides direct evidence that IL-4 inhibits epithelial cell
      migration in lung epithelial cells. This is a tissue-specific effect on non-immune
      cells in the context of airway epithelial barrier function and wound healing,
      representing a pleiotropic activity rather than a core immune function.
    supported_by:
    - reference_id: PMID:11698262
      supporting_text: In wound-healing assays of cells grown on collagen I, IL-4
        and IL-13 decreased migration, whereas IFN-gamma treatment enhanced migration,
        compared with control cells
- term:
    id: GO:0097028
    label: dendritic cell differentiation
  evidence_type: IDA
  original_reference_id: PMID:21149635
  review:
    summary: PMID:21149635 demonstrates that monocytic cells derived from human embryonic
      stem cells differentiate through pathways involving IL-4, with M2-like macrophage
      characteristics.
    action: ACCEPT
    reason: IL-4 is well-established as a key factor in dendritic cell differentiation
      from monocyte precursors. The paper studies monocyte differentiation pathways
      including IL-4 dependent steps. This is consistent with the GO:0043011 annotation.
    supported_by:
    - reference_id: PMID:21149635
      supporting_text: monocytic cells derived from human embryonic stem cells (hESCs)
        and from fetal liver follow a differentiation pathway different to that of
        adult cells
- term:
    id: GO:0045893
    label: positive regulation of DNA-templated transcription
  evidence_type: IDA
  original_reference_id: PMID:19346497
  review:
    summary: PMID:19346497 studies IFN-lambda1 inhibition of GATA3 and Th2 responses.
      The paper demonstrates IL-4-driven transcription in the context of Th2 cytokine
      gene expression. IL-4 stimulation leads to GATA3 expression and IL-4Ralpha upregulation,
      both of which are transcription-dependent processes.
    action: ACCEPT
    reason: IL-4 is a potent inducer of gene transcription through STAT6 signaling.
      This IDA annotation is consistent with multiple other annotations for the same
      term and with the known biology of IL-4.
    supported_by:
    - reference_id: PMID:19346497
      supporting_text: Expression of Th2 cytokines (IL-4 and IL-13) was suppressed
        in naive and memory CD4(+) T cells by IFN-lambda1, without affecting their
        proliferation
- term:
    id: GO:0032736
    label: positive regulation of interleukin-13 production
  evidence_type: IDA
  original_reference_id: PMID:19346497
  review:
    summary: PMID:19346497 demonstrates that IL-4-driven Th2 responses include IL-13
      production, which is suppressed by IFN-lambda1. The paper shows IL-4 promotes
      IL-13 expression as part of the Th2 cytokine program.
    action: ACCEPT
    reason: IL-4 and IL-13 are co-regulated Th2 cytokines. IL-4-driven Th2 differentiation
      via GATA3 leads to increased IL-13 production as part of the Th2 cytokine program.
      The paper directly demonstrates this relationship.
    supported_by:
    - reference_id: PMID:19346497
      supporting_text: Expression of Th2 cytokines (IL-4 and IL-13) was suppressed
        in naive and memory CD4(+) T cells by IFN-lambda1, without affecting their
        proliferation
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: IL-4 drives Th2 differentiation (via STAT6->GATA3)
- term:
    id: GO:0045582
    label: positive regulation of T cell differentiation
  evidence_type: IDA
  original_reference_id: PMID:20554961
  review:
    summary: PMID:20554961 studies IL-4-driven Th2 differentiation and how type I
      IFN opposes it. IL-4 promotes Th2 development by inducing GATA3.
    action: ACCEPT
    reason: IL-4 is the canonical driver of Th2 cell differentiation from naive T
      cells. The paper directly studies this process and demonstrates IL-4-dependent
      GATA3 induction as the key mechanism of Th2 commitment.
    supported_by:
    - reference_id: PMID:20554961
      supporting_text: IL-4 promotes Th2 development by inducing the expression of
        the GATA3 transcription factor, and the Th2 phenotype is stabilized by a GATA3-dependent
        auto-regulatory loop
- term:
    id: GO:0045893
    label: positive regulation of DNA-templated transcription
  evidence_type: IDA
  original_reference_id: PMID:20554961
  review:
    summary: PMID:20554961 demonstrates that IL-4 promotes transcription of GATA3
      through STAT6 signaling as part of Th2 commitment.
    action: ACCEPT
    reason: The paper provides direct evidence that IL-4 activates GATA3 transcription
      through STAT6, consistent with the known transcription-activating function of
      IL-4.
    supported_by:
    - reference_id: PMID:20554961
      supporting_text: IL-4 receptor signaling promotes STAT6 recruitment and phosphorylation...
        which ultimately regulates induction of GATA3 transcription
- term:
    id: GO:2000553
    label: positive regulation of T-helper 2 cell cytokine production
  evidence_type: IDA
  original_reference_id: PMID:20554961
  review:
    summary: PMID:20554961 demonstrates that IL-4 promotes Th2 cytokine production
      by driving GATA3-dependent Th2 differentiation and cytokine gene expression.
    action: ACCEPT
    reason: IL-4-driven Th2 differentiation leads to increased production of Th2 cytokines
      (IL-4, IL-5, IL-13). This is a core function of IL-4 as the master Th2-polarizing
      cytokine.
    supported_by:
    - reference_id: PMID:20554961
      supporting_text: IL-4 promotes Th2 development by inducing the expression of
        the GATA3 transcription factor
- term:
    id: GO:0045892
    label: negative regulation of DNA-templated transcription
  evidence_type: IDA
  original_reference_id: PMID:18579517
  review:
    summary: PMID:18579517 demonstrates that IL-4 stimulation negatively regulates
      expression of LEF-1 and TCF-1 transcription factors in primary T cells, creating
      a positive feedback loop that reinforces IL-4 gene expression by removing transcriptional
      repressors. This represents IL-4 negatively regulating transcription of specific
      target genes (LEF-1, TCF-1).
    action: KEEP_AS_NON_CORE
    reason: The paper provides direct evidence that IL-4 downregulates LEF-1 and TCF-1
      expression, which are Wnt pathway transcription factors. This is consistent
      with the existing KEEP_AS_NON_CORE annotation for GO:0000122 (negative regulation
      of transcription by RNA polymerase II) from PMID:11967989 for CTGF. IL-4's ability
      to repress specific genes is a real but secondary function compared to its primary
      role as a transcriptional activator through STAT6.
    supported_by:
    - reference_id: PMID:18579517
      supporting_text: we found that IL-4 stimulation possesses a negative effect
        on the expressions of LEF-1 and TCF-1 in primary T cells, suggesting a positive
        feedback effect of IL-4 on IL4 gene expression
- term:
    id: GO:0045893
    label: positive regulation of DNA-templated transcription
  evidence_type: IDA
  original_reference_id: PMID:18579517
  review:
    summary: PMID:18579517 demonstrates that IL-4 positively regulates its own gene
      expression through a feedback mechanism. IL-4 stimulation suppresses LEF-1 and
      TCF-1, which are negative regulators of the IL-4 promoter. Knockdown of LEF-1
      by siRNA increased IL-4 mRNA expression, confirming that LEF-1 is a transcriptional
      repressor of IL-4. By removing this repression, IL-4 indirectly promotes transcription
      of IL-4 and potentially other Th2 cytokine genes.
    action: ACCEPT
    reason: The paper provides evidence that IL-4 positively regulates transcription
      through a feedback loop involving suppression of LEF-1/TCF-1 transcriptional
      repressors. This is consistent with the other ACCEPT annotations for GO:0045893
      from IBA, IDA (PMID:19346497, PMID:20554961), which all document IL-4's well-established
      role as a transcriptional activator via STAT6 signaling.
    supported_by:
    - reference_id: PMID:18579517
      supporting_text: Knockdown LEF-1 expression by LEF-1-specific small interfering
        RNA resulted in an increase in the IL-4 mRNA expression
    - reference_id: PMID:18579517
      supporting_text: we found that IL-4 stimulation possesses a negative effect
        on the expressions of LEF-1 and TCF-1 in primary T cells, suggesting a positive
        feedback effect of IL-4 on IL4 gene expression
- term:
    id: GO:0008203
    label: cholesterol metabolic process
  evidence_type: ISS
  original_reference_id: PMID:11971948
  review:
    summary: PMID:11971948 demonstrates that IL-4-deficient mice have a 100% incidence
      of gallstones and cholesterol crystals on a fat-enriched diet, compared to no
      gallstones in wild-type mice, suggesting IL-4 plays a role in cholesterol metabolism.
      ISS from mouse IL-4 (P07750).
    action: KEEP_AS_NON_CORE
    reason: The paper provides genetic evidence that IL-4 deficiency predisposes to
      gallstone formation and altered cholesterol metabolism. However, this is a pleiotropic
      downstream effect rather than a core immune function of IL-4.
    supported_by:
    - reference_id: PMID:11971948
      supporting_text: IL-4(-/-) mice had a 100% incidence of gallstones and cholesterol
        crystals
- term:
    id: GO:0030890
    label: positive regulation of B cell proliferation
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 promotes B cell proliferation as one of its defining functions.
      Originally named B-cell stimulatory factor 1 (BSF-1) for this activity. Transferred
      from mouse IL-4 (P07750).
    action: ACCEPT
    reason: B cell proliferation is a core function of IL-4. It was originally identified
      as BSF-1 precisely for its B cell growth-promoting activity. The ISS from mouse
      is well-supported by extensive human data.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: AltName...B-cell stimulatory factor 1; Short=BSF-1
- term:
    id: GO:0042102
    label: positive regulation of T cell proliferation
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 promotes T cell proliferation, particularly of Th2-committed cells.
      Also known as lymphocyte stimulatory factor 1. Transferred from mouse IL-4 (P07750).
    action: ACCEPT
    reason: T cell proliferation promotion is a known function of IL-4, consistent
      with its alternative name as lymphocyte stimulatory factor 1. The ISS from mouse
      is well-supported.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: AltName...Lymphocyte stimulatory factor 1
- term:
    id: GO:0043066
    label: negative regulation of apoptotic process
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 has well-documented anti-apoptotic effects, promoting survival of
      B cells, T cells, and other immune cells through PI3K/Akt signaling. Transferred
      from mouse IL-4 (P07750).
    action: KEEP_AS_NON_CORE
    reason: While IL-4 has anti-apoptotic effects through IRS-2/PI3K signaling, this
      is a secondary consequence of its signaling rather than a core function. The
      annotation is not incorrect but represents a downstream effect.
- term:
    id: GO:0045348
    label: positive regulation of MHC class II biosynthetic process
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 induces MHC class II expression on B cells, enhancing their antigen-presenting
      capacity. This is one of IL-4's original defining functions. Transferred from
      mouse IL-4 (P07750).
    action: ACCEPT
    reason: MHC class II upregulation on B cells by IL-4 is one of the earliest described
      functions of this cytokine and is directly documented in the UniProt function
      annotation. The ISS from mouse is well-supported by human data.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Induces the expression of class II MHC molecules on resting
        B-cells
- term:
    id: GO:0045671
    label: negative regulation of osteoclast differentiation
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 has been reported to inhibit osteoclast differentiation, likely
      through anti-inflammatory effects that oppose RANKL signaling. Transferred from
      mouse IL-4 (P07750).
    action: KEEP_AS_NON_CORE
    reason: While IL-4 may inhibit osteoclastogenesis, this is a specialized tissue-specific
      effect rather than a core immune function. The ISS annotation is from mouse
      data and represents a pleiotropic activity.
- term:
    id: GO:0045944
    label: positive regulation of transcription by RNA polymerase II
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 activates RNA polymerase II-dependent transcription through STAT6-mediated
      signaling. Transferred from mouse IL-4 (P07750).
    action: ACCEPT
    reason: This is well-supported by the IGI annotation with the same term from PMID:12574355
      and by the known mechanism of STAT6-dependent gene activation. The ISS from
      mouse is consistent with human data.
- term:
    id: GO:0048295
    label: positive regulation of isotype switching to IgE isotypes
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 is the primary cytokine that drives B cell class switch recombination
      to IgE. This is arguably the most important and specific function of IL-4 in
      adaptive immunity, and the basis for anti-IL-4 therapy in allergic disease.
      Transferred from mouse IL-4 (P07750).
    action: ACCEPT
    reason: IgE class switching is THE defining function of IL-4 in B cell biology.
      IL-4 induces germline epsilon transcription through STAT6 signaling, which is
      required for IgE class switch recombination. This is the mechanistic basis for
      dupilumab therapy in allergic diseases.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Enhances both secretion and cell surface expression of IgE
        and IgG1
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: IL-4 drives...B-cell proliferation and class-switch recombination
        to IgE
- term:
    id: GO:0048304
    label: positive regulation of isotype switching to IgG isotypes
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 promotes IgG1 (in mouse) and IgG4 (in human) class switching. Transferred
      from mouse IL-4 (P07750).
    action: ACCEPT
    reason: IL-4 promotes IgG class switching in addition to IgE switching. In humans,
      IL-4 drives switching to IgG4; in mice, to IgG1. This is a well-established
      function.
    supported_by:
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Enhances both secretion and cell surface expression of IgE
        and IgG1
- term:
    id: GO:0050776
    label: regulation of immune response
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  review:
    summary: IL-4 regulates immune responses, particularly type 2 immunity. Transferred
      from mouse IL-4 (P07750). Duplicate of the IBA annotation.
    action: ACCEPT
    reason: Duplicate of the IBA annotation with ISS evidence. Both are correct and
      complementary.
- term:
    id: GO:0005136
    label: interleukin-4 receptor binding
  evidence_type: TAS
  original_reference_id: PMID:3016727
  review:
    summary: PMID:3016727 is the original paper by Yokota et al. (1986) reporting
      the cloning and characterization of human IL-4 cDNA, including its B-cell and
      T-cell stimulating activities through receptor binding.
    action: ACCEPT
    reason: This is the seminal paper identifying human IL-4. The TAS annotation for
      IL-4 receptor binding from the original characterization paper is historically
      and scientifically well-supported.
    supported_by:
    - reference_id: PMID:3016727
      supporting_text: Supernatant of COS-7 monkey cells transfected with the human
        cDNA clone stimulated proliferation of human helper T-cell clones and of anti-IgM-activated
        human B cells, two properties of mouse BSF-1 on mouse cells
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), AND FUNCTION...Isolation
        and characterization of a human interleukin cDNA clone, homologous to mouse
        B-cell stimulatory factor 1
- term:
    id: GO:0005615
    label: extracellular space
  evidence_type: TAS
  original_reference_id: PMID:3016727
  review:
    summary: The original IL-4 cloning paper by Yokota et al. (1986) characterizes
      IL-4 as a secreted protein with a putative signal peptide and extracellular
      activity.
    action: ACCEPT
    reason: Correct localization annotation from the original characterization paper.
    supported_by:
    - reference_id: PMID:3016727
      supporting_text: The human cDNA contains a single open reading frame encoding
        a protein of 153 amino acid residues including a putative signal peptide
- term:
    id: GO:0006955
    label: immune response
  evidence_type: TAS
  original_reference_id: PMID:3016727
  review:
    summary: IL-4 was characterized as an immune response cytokine in the original
      cloning paper, showing B-cell and T-cell stimulating activities.
    action: ACCEPT
    reason: IL-4 is fundamentally an immune response mediator. The TAS annotation
      from the original characterization paper is correct.
    supported_by:
    - reference_id: PMID:3016727
      supporting_text: Supernatant of COS-7 monkey cells transfected with the human
        cDNA clone stimulated proliferation of human helper T-cell clones and of anti-IgM-activated
        human B cells
- term:
    id: GO:0005136
    label: interleukin-4 receptor binding
  evidence_type: TAS
  original_reference_id: PMID:11418631
  review:
    summary: PMID:11418631 studies IL-4 receptor-mediated signaling in the context
      of germinal center B cell differentiation, demonstrating that IL-4 acts through
      its receptor to direct GC-B cell fate toward memory B cells.
    action: ACCEPT
    reason: IL-4 receptor binding is the core molecular function. The paper demonstrates
      IL-4 receptor-mediated biological effects. Duplicate with different reference
      is acceptable.
    supported_by:
    - reference_id: PMID:11418631
      supporting_text: IL-4 directs GC-B cells to differentiate into memory B cells,
        whereas IL-10 steers them into PC
- term:
    id: GO:0005615
    label: extracellular space
  evidence_type: TAS
  original_reference_id: PMID:11418631
  review:
    summary: PMID:11418631 studies the effects of T cell-derived cytokines including
      secreted IL-4 on germinal center B cell differentiation, consistent with IL-4
      activity in the extracellular space.
    action: ACCEPT
    reason: Correct localization. IL-4 is a secreted cytokine that acts in the extracellular
      space. Duplicate with different reference is acceptable.
    supported_by:
    - reference_id: PMID:11418631
      supporting_text: cytokines secreted by activated T cells determined the pathway
        of GC-B cell differentiation
- term:
    id: GO:0008083
    label: growth factor activity
  evidence_type: NAS
  original_reference_id: PMID:11418631
  review:
    summary: PMID:11418631 demonstrates that IL-4 and FDC signals provide growth-promoting
      signals for germinal center B cells. IL-4 has growth factor activity for B and
      T cells (originally named BSF-1).
    action: KEEP_AS_NON_CORE
    reason: While IL-4 has growth-promoting activity for lymphocytes, its primary
      molecular function is better described as cytokine activity and IL-4 receptor
      binding. Growth factor activity is a secondary characterization.
    supported_by:
    - reference_id: PMID:11418631
      supporting_text: FDC/HK cells do not direct either pathway, but provide signals
        for proliferation of GC-B cells
- term:
    id: GO:0030183
    label: B cell differentiation
  evidence_type: TAS
  original_reference_id: PMID:11418631
  review:
    summary: PMID:11418631 directly demonstrates that IL-4 directs germinal center
      B cells to differentiate into memory B cells, while IL-10 steers them toward
      plasma cells.
    action: ACCEPT
    reason: B cell differentiation is a core function of IL-4. The paper provides
      direct evidence for IL-4's role in directing GC-B cell differentiation pathways.
    supported_by:
    - reference_id: PMID:11418631
      supporting_text: IL-4 directs GC-B cells to differentiate into memory B cells,
        whereas IL-10 steers them into PC
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Enhances both secretion and cell surface expression of IgE
        and IgG1
- term:
    id: GO:0042092
    label: type 2 immune response
  evidence_type: TAS
  original_reference_id: PMID:11676128
  review:
    summary: PMID:11676128 reviews IL-4, IL-5, and IL-13 as Th2 cytokines pivotal
      in regulating the allergic phenotype, IgE response, and inflammatory cell-mediated
      function. IL-4 is THE defining cytokine of type 2 immune responses.
    action: ACCEPT
    reason: Type 2 immune response is the most accurate high-level description of
      IL-4's biological role. IL-4 is the master regulator of type 2 immunity.
    supported_by:
    - reference_id: PMID:11676128
      supporting_text: Th2 cytokines, such as IL-4, IL-5 and IL-13, are pivotal in
        regulating the allergic phenotype, the IgE response or the inflammatory cell-mediated
        function
    - reference_id: file:human/IL4/IL4-deep-research-falcon.md
      supporting_text: IL-4 is a central driver of type-2 endotypes (eosinophilic/allergic)
        across airway and barrier diseases
- term:
    id: GO:0045191
    label: regulation of isotype switching
  evidence_type: TAS
  original_reference_id: PMID:11418631
  review:
    summary: PMID:11418631 studies the role of T cell-derived cytokines including
      IL-4 in germinal center B cell differentiation, which includes isotype switching.
      IL-4 is the primary cytokine regulating class switch recombination to IgE and
      IgG4 in humans.
    action: ACCEPT
    reason: Isotype switching regulation is a core function of IL-4. More specific
      child terms (IgE and IgG switching) are also annotated. This general term appropriately
      captures the broader regulatory role.
    supported_by:
    - reference_id: PMID:11418631
      supporting_text: IL-4 directs GC-B cells to differentiate into memory B cells,
        whereas IL-10 steers them into PC
    - reference_id: file:human/IL4/IL4-uniprot.txt
      supporting_text: Enhances both secretion and cell surface expression of IgE
        and IgG1
references:
- id: GO_REF:0000002
  title: Gene Ontology annotation through association of InterPro records with GO
    terms
  findings: []
- id: GO_REF:0000024
  title: Manual transfer of experimentally-verified manual GO annotation data to orthologs
    by curator judgment of sequence similarity
  findings: []
- id: GO_REF:0000033
  title: Annotation inferences using phylogenetic trees
  findings: []
- id: GO_REF:0000043
  title: Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping
  findings: []
- id: GO_REF:0000111
  title: Gene Ontology annotations Inferred by Curator (IC) using at least one Inferred
    by Sequence Similarity (ISS) annotation to support the inference
  findings: []
- id: GO_REF:0000117
  title: Electronic Gene Ontology annotations created by ARBA machine learning models
  findings: []
- id: GO_REF:0000120
  title: Combined Automated Annotation using Multiple IEA Methods
  findings: []
- id: PMID:3016727
  title: Isolation and characterization of a human interleukin cDNA clone, homologous
    to mouse B-cell stimulatory factor 1, that expresses B-cell- and T-cell-stimulating
    activities
  findings:
  - statement: Original cloning and characterization of human IL-4 as a secreted cytokine
      with B cell and T cell stimulating activities.
    supporting_text: Supernatant of COS-7 monkey cells transfected with the human
      cDNA clone stimulated proliferation of human helper T-cell clones and of anti-IgM-activated
      human B cells, two properties of mouse BSF-1 on mouse cells
- id: PMID:10219247
  title: Crystal structure of the interleukin-4/receptor alpha chain complex reveals
    a mosaic binding interface
  findings:
  - statement: Crystal structure at 2.30 angstroms reveals the IL-4/IL4RA binding
      interface and demonstrates direct ligand-receptor interaction.
    supporting_text: The crystal structure of the intermediate complex between human
      IL-4 and IL4-BP was determined at 2.3 A resolution. It reveals a novel spatial
      orientation of the two proteins, a small but unexpected conformational change
      in the receptor-bound IL-4, and an interface with three separate clusters of
      trans-interacting residues
- id: PMID:11418631
  title: The distinct roles of T cell-derived cytokines and a novel follicular dendritic
    cell-signaling molecule 8D6 in germinal center-B cell differentiation.
  findings:
  - statement: Characterization of IL-4 receptor binding, growth factor activity,
      and role in B cell differentiation and isotype switching.
    supporting_text: IL-4 directs GC-B cells to differentiate into memory B cells,
      whereas IL-10 steers them into PC
- id: PMID:11676128
  title: '[Inflammatory cytokines (IL-4, IL-5 and IL-13)].'
  findings:
  - statement: Documents IL-4 role in type 2 immune responses.
    supporting_text: Th2 cytokines, such as IL-4, IL-5 and IL-13, are pivotal in regulating
      the allergic phenotype, the IgE response or the inflammatory cell-mediated function
- id: PMID:11698262
  title: Lung epithelial barrier function and wound healing are decreased by IL-4
    and IL-13 and enhanced by IFN-gamma.
  findings:
  - statement: IL-4 and IL-13 decrease lung epithelial barrier function and wound
      healing, inhibiting epithelial cell migration on collagen substrates.
    supporting_text: In wound-healing assays of cells grown on collagen I, IL-4 and
      IL-13 decreased migration, whereas IFN-gamma treatment enhanced migration, compared
      with control cells
- id: PMID:11967989
  title: Interleukin-4 regulates connective tissue growth factor expression in human
    lung fibroblasts.
  findings:
  - statement: IL-4 attenuates TGF-beta-stimulated CTGF expression in lung fibroblasts
      by interfering with TGF-beta-induced transcriptional activation of the CTGF
      gene.
    supporting_text: IL-4 attenuated the TGF-beta-stimulated induction of CTGF mRNA
      expression by 50%. This effect was selective because IL-4 did not affect fibronectin
      or alpha1(I) collagen mRNA expression induced by TGF-beta
- id: PMID:11971948
  title: Interleukin-4 deficiency promotes gallstone formation.
  findings:
  - statement: IL-4 deficiency in mice promotes gallstone formation on a fat-enriched
      diet, suggesting a role for IL-4 in cholesterol metabolism.
    supporting_text: IL-4(-/-) mice had a 100% incidence of gallstones and cholesterol
      crystals
- id: PMID:12574355
  title: 'Human activation-induced cytidine deaminase is induced by IL-4 and negatively
    regulated by CD45: implication of CD45 as a Janus kinase phosphatase in antibody
    diversification'
  findings:
  - statement: IL-4 induces AID expression in human B cells via JAK/STAT6 signaling,
      enhanced by CD40 co-stimulation, and negatively regulated by CD45 JAK phosphatase
      activity.
    supporting_text: IL-4 was able to induce AID expression in human primary B cells
      and B cell lines, and IL-4-induced AID expression was further enhanced by CD40
      signaling. IL-4-dependent AID induction was inhibited by a dominant-negative
      STAT6, indicating that IL-4 induced AID expression via the Janus kinase (JAK)/STAT6
      signaling pathway
- id: PMID:16034134
  title: IL-4 and IL-13 induce protection of porcine endothelial cells from killing
    by human complement and from apoptosis through activation of a phosphatidylinositide
    3-kinase/Akt pathway.
  findings:
  - statement: IL-4 and IL-13 protect porcine endothelial cells from complement-mediated
      killing and apoptosis via PI3K/Akt pathway activation.
    supporting_text: porcine EC incubated with IL-4 or IL-13, but not with IL-10 or
      IL-11, became protected from killing by complement and apoptosis induced by
      TNF-alpha plus cycloheximide
- id: PMID:16116184
  title: Galectin-9 induces maturation of human monocyte-derived dendritic cells.
  findings:
  - statement: IL-4 drives myeloid dendritic cell differentiation from monocyte precursors.
    supporting_text: Culture of immature DCs with exogenous Gal-9 markedly increased
      the surface expression of CD40, CD54, CD80, CD83, CD86, and HLA-DR in a dose-dependent
      manner, although Gal-9 had no or little effect on differentiation of human monocytes
      into immature DCs
- id: PMID:16606666
  title: B7-H4 expression identifies a novel suppressive macrophage population in
    human ovarian carcinoma.
  findings:
  - statement: IL-4 inhibits B7-H4 expression on macrophages, in contrast to IL-6
      and IL-10 which stimulate it, relevant to tumor immune evasion.
    supporting_text: granulocyte/macrophage colony-stimulating factor and IL-4, which
      are limited in the tumor microenvironment, inhibit B7-H4 expression
- id: PMID:18243101
  title: Molecular and structural basis of cytokine receptor pleiotropy in the interleukin-4/13
    system
  findings:
  - statement: Crystal structure reveals molecular basis for IL-4 signaling through
      both type I (IL4RA/IL2RG) and type II (IL4RA/IL13RA1) receptor complexes, explaining
      cytokine receptor pleiotropy.
    supporting_text: Here we present the crystal structures of the complete set of
      type I (IL-4R alpha/gamma(c)/IL-4) and type II (IL-4R alpha/IL-13R alpha1/IL-4,
      IL-4R alpha/IL-13R alpha1/IL-13) ternary signaling complexes
- id: PMID:18337562
  title: CCL5-mediated T-cell chemotaxis involves the initiation of mRNA translation
    through mTOR/4E-BP1.
  findings:
  - statement: Study of CCL5-mediated T cell chemotaxis mechanisms; relevance to IL-4
      T cell activation annotation is unclear.
    supporting_text: The multistep, coordinated process of T-cell chemotaxis requires
      chemokines, and their chemokine receptors, to invoke signaling events to direct
      cell migration
- id: PMID:18579517
  title: LEF-1 negatively controls interleukin-4 expression through a proximal promoter
    regulatory element.
  findings:
  - statement: LEF-1 is a transcriptional repressor of IL-4 gene expression. IL-4
      stimulation downregulates LEF-1 and TCF-1, creating a positive feedback loop
      that reinforces IL-4 expression.
    supporting_text: Knockdown LEF-1 expression by LEF-1-specific small interfering
      RNA resulted in an increase in the IL-4 mRNA expression
- id: PMID:19346497
  title: IFN-lambda1 (IL-29) inhibits GATA3 expression and suppresses Th2 responses
    in human naive and memory T cells.
  findings:
  - statement: IFN-lambda1 suppresses IL-4-driven Th2 responses by inhibiting GATA3
      expression and Th2 cytokine (IL-4, IL-13) production in naive and memory T cells.
    supporting_text: Expression of Th2 cytokines (IL-4 and IL-13) was suppressed in
      naive and memory CD4(+) T cells by IFN-lambda1, without affecting their proliferation
- id: PMID:20554961
  title: 'Cutting edge: Type I IFN reverses human Th2 commitment and stability by
    suppressing GATA3'
  findings:
  - statement: IL-4 promotes Th2 development by inducing GATA3 expression via STAT6;
      GATA3 autoregulation maintains Th2 stability; type I IFN can reverse this.
    supporting_text: IL-4 promotes Th2 development by inducing the expression of the
      GATA3 transcription factor, and the Th2 phenotype is stabilized by a GATA3-dependent
      autoregulatory loop
- id: PMID:21149635
  title: Monocytic cells derived from human embryonic stem cells and fetal liver share
    common differentiation pathways and homeostatic functions
  findings:
  - statement: Demonstrates IL-4-dependent monocyte-to-dendritic cell differentiation
      pathways in human embryonic and fetal systems.
    supporting_text: monocytic cells derived from human embryonic stem cells (hESCs)
      and from fetal liver follow a differentiation pathway different to that of adult
      cells, leading to specific functions
- id: PMID:23103943
  title: Redirecting cell-type specific cytokine responses with engineered interleukin-4
    superkines.
  findings:
  - statement: Documents IL-4 signaling through JAK-STAT pathway and leukocyte differentiation.
    supporting_text: Formation of the IL-4/IL-4Rα/γc or IL-4/IL-4Rα/IL-13Rα1 complex
      on the cell surface activates intracellular signaling pathways including the
      Jak-STAT and the PI3K/Akt pathways
- id: PMID:23597562
  title: Inhibition of tumor angiogenesis and growth by a small-molecule multi-FGF
    receptor blocker with allosteric properties
  findings:
  - statement: Study focuses on FGFR inhibitors; IL-4/IL4R interaction likely from
      high-throughput IntAct data associated with this publication.
    supporting_text: we report the pharmacologic characterization of the chemical
      SSR128129E (SSR), which inhibits fibroblast growth factor receptor (FGFR) signaling
      by binding to the extracellular FGFR domain without affecting orthosteric FGF
      binding
- id: PMID:24906148
  title: Eosinophils and type 2 cytokine signaling in macrophages orchestrate development
    of functional beige fat.
  findings:
  - statement: IL-4/IL-13 signaling in macrophages is required for cold-induced beige
      fat biogenesis. IL-4 administration increases beige fat and ameliorates obesity.
    supporting_text: Genetic loss of eosinophils or IL-4/13 signaling impairs cold-induced
      biogenesis of beige fat
- id: PMID:30634164
  title: IL-16 regulates macrophage polarization as a target gene of mir-145-3p.
  findings:
  - statement: IL-4 and IL-13 induce M2 macrophage polarization with higher IL-10
      and lower pro-inflammatory cytokine expression compared to M1 macrophages.
    supporting_text: THP-1 cells were induced by IL-4 and IL-13 following PMA incubation
      (M2 polarized macrophages) or induced by IFN-gamma and LPS (M1 classical macrophage
      activation)
- id: PMID:31432141
  title: miR‑320a upregulation contributes to the development of preeclampsia by inhibiting
    the growth and invasion of trophoblast cells by targeting interleukin 4.
  findings:
  - statement: IL-4 is a direct target of miR-320a in trophoblast cells. IL-4 promotes
      trophoblast proliferation and invasion, and miR-320a-mediated IL-4 suppression
      contributes to preeclampsia pathogenesis.
    supporting_text: miR-320a upregulation inhibited the proliferation and invasion
      of HTR-8/SVneo cells by directly targeting IL-4
- id: PMID:3279117
  title: Modulation of phenotypic and functional properties of human peripheral blood
    monocytes by IL-4.
  findings:
  - statement: IL-4 modulates monocyte phenotype and function, inducing macrophage-like
      morphology, MHC class II upregulation, and inhibiting secretion of cytostatic
      and chemotactic compounds.
    supporting_text: Highly purified peripheral blood monocytes were cultured in the
      presence of rIL-4
- id: PMID:8266078
  title: 'Interleukin-2 receptor gamma chain: a functional component of the interleukin-4
    receptor.'
  findings:
  - statement: The IL-2 receptor gamma chain is a functional component of the IL-4
      receptor, demonstrated by chemical cross-linking, binding affinity augmentation,
      and requirement for IL-4-mediated IRS-1 phosphorylation.
    supporting_text: IL-2R gamma was demonstrated to be a component of the IL-4 receptor
      on the basis of chemical cross-linking data, the ability of IL-2R gamma to augment
      IL-4 binding affinity, and the requirement for IL-2R gamma in IL-4-mediated
      phosphorylation of insulin receptor substrate-1
- id: Reactome:R-HSA-6785821
  title: SOCS5,(SOCS1) bind IL4RA
  findings: []
- id: Reactome:R-HSA-6786058
  title: JAK1 binds IL4R in IL4-bound IL4R1
  findings: []
- id: Reactome:R-HSA-6786070
  title: IL4:IL4R:JAK2 binds IL13RA1:TYK2
  findings: []
- id: Reactome:R-HSA-6786072
  title: p-Y705-STAT3,p-Y641-STAT6 dissociate
  findings: []
- id: Reactome:R-HSA-6786092
  title: IL4:IL4R:JAK2 binds IL2RG:JAK3
  findings: []
- id: Reactome:R-HSA-6786095
  title: JAK1 phosphorylates STAT3,STAT6
  findings: []
- id: Reactome:R-HSA-6786096
  title: IL4R, IL2RG, JAK1 in IL4-bound IL4R1:JAK1 are phosphorylated
  findings: []
- id: Reactome:R-HSA-6786101
  title: IL4 binds IL4R:JAK2
  findings: []
- id: Reactome:R-HSA-6786124
  title: STAT3,STAT6 bind p-Y-IL4R
  findings: []
core_functions:
- description: IL-4 binds the IL-4 receptor alpha chain (IL4RA) to initiate type I
    (IL4RA/IL2RG) and type II (IL4RA/IL13RA1) receptor complex assembly, driving JAK1/JAK3-STAT6
    signaling that promotes Th2 differentiation, IgE class switching, and type 2 immune
    responses
  supported_by:
  - reference_id: PMID:10219247
    supporting_text: Crystal structure of the interleukin-4/receptor alpha chain complex
      reveals a mosaic binding interface
  - reference_id: PMID:12574355
    supporting_text: IL-4 induced AID expression via the Janus kinase (JAK)/STAT6
      signaling pathway
  - reference_id: file:human/IL4/IL4-deep-research-falcon.md
    supporting_text: IL-4 is a central driver of type-2 endotypes
  molecular_function:
    id: GO:0005136
    label: interleukin-4 receptor binding
  directly_involved_in:
  - id: GO:0035771
    label: interleukin-4-mediated signaling pathway
  - id: GO:0042092
    label: type 2 immune response
  - id: GO:0048295
    label: positive regulation of isotype switching to IgE isotypes
  locations:
  - id: GO:0005576
    label: extracellular region
- description: IL-4 drives naive CD4+ T cell differentiation into Th2 effector cells
    through STAT6-dependent GATA3 induction, promoting type 2 adaptive immunity
  supported_by:
  - reference_id: PMID:20554961
    supporting_text: IL-4 promotes Th2 development by inducing the expression of the
      GATA3 transcription factor
  molecular_function:
    id: GO:0005136
    label: interleukin-4 receptor binding
  directly_involved_in:
  - id: GO:0045582
    label: positive regulation of T cell differentiation
  - id: GO:0045893
    label: positive regulation of DNA-templated transcription
  locations:
  - id: GO:0005576
    label: extracellular region
- description: IL-4 promotes B cell activation, proliferation, and class switch recombination
    to IgE and IgG4, through induction of AID expression via STAT6
  supported_by:
  - reference_id: PMID:12574355
    supporting_text: IL-4 was able to induce AID expression in human primary B cells
      and B cell lines, and IL-4-induced AID expression was further enhanced by CD40
      signaling
  - reference_id: file:human/IL4/IL4-uniprot.txt
    supporting_text: Enhances both secretion and cell surface expression of IgE and
      IgG1
  molecular_function:
    id: GO:0005136
    label: interleukin-4 receptor binding
  directly_involved_in:
  - id: GO:0042113
    label: B cell activation
  - id: GO:0048295
    label: positive regulation of isotype switching to IgE isotypes
  locations:
  - id: GO:0005576
    label: extracellular region
- description: IL-4 suppresses pro-inflammatory responses by inhibiting Th1 differentiation
    and macrophage pro-inflammatory cytokine production, promoting M2 macrophage polarization
  supported_by:
  - reference_id: file:human/IL4/IL4-deep-research-falcon.md
    supporting_text: IL-4 is a central driver of type-2 endotypes (eosinophilic/allergic)
      across airway and barrier diseases
  molecular_function:
    id: GO:0005136
    label: interleukin-4 receptor binding
  directly_involved_in:
  - id: GO:0050728
    label: negative regulation of inflammatory response
  - id: GO:0042116
    label: macrophage activation
  locations:
  - id: GO:0005576
    label: extracellular region