Comprehensive Research Report: Functional Annotation of Human TLR4 (UniProt: O00206, Gene: TLR4) Falcon Edison Scientific Literature 52 citations 3 artifacts 2026-09-30T06:04:57.553716

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this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.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: Functional Annotation of Human TLR4 (UniProt: O00206, Gene: TLR4)

1. Gene and Protein Identity Verification

TLR4 (Toll-like receptor 4, UniProt: O00206) in Homo sapiens is an established member of the Toll-like receptor family, as confirmed by all recent and authoritative sources. The protein contains leucine-rich repeat domains that mediate its ligand-binding function and belongs to the pattern recognition receptor superfamily, consistent with its UniProt description (kashani2021theroleof pages 1-2, sameer2021tolllikereceptors(tlrs) pages 3-5, behzadi2021tolllikereceptorsgeneral pages 12-13).

2. Key Concepts, Structure, and Definitions

Structure and Essential Domains

TLR4 is a type I transmembrane receptor consisting of:
- An extracellular domain with ~22 leucine-rich repeats (LRRs) for ligand recognition;
- A single transmembrane segment;
- An intracellular TIR domain for downstream signaling (behzadi2021tolllikereceptorsgeneral pages 12-13, luo2025anexaminationof pages 2-4, sameer2021tolllikereceptors(tlrs) pages 2-3, stierschneider2023sheddinglighton pages 1-2).
TLR4 functions as a homodimer, each monomer associating with MD-2 (a soluble co-receptor essential for LPS binding and response), and uses CD14 as an accessory co-receptor for ligand transfer and presentation (behzadi2021tolllikereceptorsgeneral pages 12-13, luo2025anexaminationof pages 2-4).

Functional Definition

TLR4’s primary molecular role is that of a pattern recognition receptor (PRR) of the innate immune system. It senses a range of exogenous pathogen-associated molecular patterns (PAMPs), especially lipopolysaccharide (LPS) from Gram-negative bacteria, as well as endogenous danger-associated molecular patterns (DAMPs) released during host tissue damage or stress (kashani2021theroleof pages 1-2, stierschneider2023sheddinglighton pages 1-2, luo2025anexaminationof pages 1-2, behzadi2021tolllikereceptorsgeneral pages 12-13).

3. Ligand Specificity and Primary Function

The canonical ligand for TLR4 is bacterial LPS, specifically the lipid A moiety, which is delivered through LBP and CD14 and recognized by the MD-2–TLR4 complex. Ligand engagement triggers homodimerization and activates intracellular signal transduction (kim2023tolllikereceptor4 pages 2-3, behzadi2021tolllikereceptorsgeneral pages 12-13, luo2025anexaminationof pages 2-4).

TLR4 also detects numerous endogenous DAMPs such as HMGB1, heat shock proteins (HSP60, HSP70, HSP90), S100A8/A9, fibrinogen, and oxidized phospholipids, among others (aboudounya2021covid19andtolllike pages 7-8, xiao2020keyplayerin pages 4-5, tominari2024rolesoftolllike pages 6-7, behzadi2021tolllikereceptorsgeneral pages 4-4, kim2023tolllikereceptor4 pages 1-2). The spectrum of ligands is summarized below:

Main category Specific ligand or ligand class Origin/source and evidentiary qualification Citations
Exogenous PAMP Lipopolysaccharide (LPS), especially lipid A Outer membrane of Gram-negative bacteria; canonical and best-established TLR4 agonist. LBP extracts/transfers LPS to CD14, which presents it to MD-2–TLR4; hexa-acylated, bisphosphorylated lipid A is strongly agonistic for human TLR4–MD-2. (luo2025anexaminationof pages 1-2, luo2025anexaminationof pages 2-4, behzadi2021tolllikereceptorsgeneral pages 12-13)
Exogenous PAMP Structurally atypical LPS or lipid-A variants Produced by diverse Gram-negative bacteria; differences in acyl-chain number/length and phosphate substitution can produce full, weak, species-specific, or antagonistic TLR4 activity. (sameer2021tolllikereceptors(tlrs) pages 3-5, tsukidate2023smallmoleculemodulators pages 2-4)
Exogenous PAMP Protozoan glycosylphosphatidylinositol (GPI) anchors Membrane-anchor glycoconjugates from protist pathogens; reported as microbial structures recognized through TLR4. (stierschneider2023sheddinglighton pages 1-2)
Exogenous PAMP Bacterial heat-shock proteins Stress proteins released or exposed by bacteria; reported as exogenous TLR4-associated ligands, although contamination with microbial lipids must be excluded experimentally. (kashani2021theroleof pages 1-2)
Exogenous PAMP Viral fusion proteins, including respiratory syncytial virus F protein Viral-envelope fusion proteins; RSV F–TLR4/MD-2 interaction has been proposed and modeled, but is less firmly established than LPS recognition. (kashani2021theroleof pages 1-2)
Exogenous non-PAMP stimulus Paclitaxel (taxol) Plant-derived xenobiotic and anticancer drug reported to activate TLR4–MD-2 in a species-dependent manner; it is not a microbial PAMP. (kashani2021theroleof pages 1-2, sameer2021tolllikereceptors(tlrs) pages 3-5)
Endogenous DAMP High-mobility group box 1 (HMGB1), particularly disulfide HMGB1 Nuclear protein released by necrotic or damaged cells and actively secreted by immune cells; extracellular HMGB1 and HMGB1–nucleic-acid complexes can engage inflammatory TLR4-associated pathways. (aboudounya2021covid19andtolllike pages 7-8, xiao2020keyplayerin pages 4-5, tominari2024rolesoftolllike pages 6-7)
Endogenous DAMP Heat-shock proteins HSP60, HSP70 and HSP90 Host stress proteins released or exposed during cellular injury; HSP60/HSP70 are frequently reported to promote TLR4–MyD88–NF-κB signaling. Direct-ligand claims require careful exclusion of endotoxin contamination. (xiao2020keyplayerin pages 4-5, behzadi2021tolllikereceptorsgeneral pages 4-4, kim2023tolllikereceptor4 pages 1-2)
Endogenous DAMP S100A8/S100A9 proteins Host alarmins released by activated or damaged myeloid and tissue cells; associated with TLR4-driven inflammation and tissue injury. (aboudounya2021covid19andtolllike pages 7-8, xiao2020keyplayerin pages 4-5, tominari2024rolesoftolllike pages 6-7)
Endogenous DAMP Fibrinogen Plasma coagulation protein exposed or deposited during vascular leakage and tissue injury; reported as an endogenous TLR4-activating matrix-associated signal. (kashani2021theroleof pages 1-2, xiao2020keyplayerin pages 4-5, sameer2021tolllikereceptors(tlrs) pages 3-5)
Endogenous DAMP Fibronectin, particularly injury-associated fragments or isoforms Extracellular-matrix glycoprotein released or remodeled during tissue damage; reported as a TLR4-associated DAMP. (kashani2021theroleof pages 1-2, xiao2020keyplayerin pages 4-5)
Endogenous DAMP Heparan sulfate Extracellular-matrix and cell-surface glycosaminoglycan fragments generated during tissue injury; reported to activate TLR4-associated inflammatory signaling. (kashani2021theroleof pages 1-2, xiao2020keyplayerin pages 4-5)
Endogenous DAMP Hyaluronan fragments Extracellular-matrix glycosaminoglycan fragments produced during matrix degradation and tissue injury; reported as endogenous TLR4-associated stimuli. (sameer2021tolllikereceptors(tlrs) pages 3-5)
Endogenous DAMP Versican Injury- and tumor-associated extracellular-matrix proteoglycan; reported as an endogenous TLR4-associated inflammatory ligand. (behzadi2021tolllikereceptorsgeneral pages 5-5)
Endogenous DAMP Oxidized phospholipids Host membrane phospholipids modified by oxidative stress, infection, or tissue injury; implicated in context-dependent TLR4-associated inflammation. (aboudounya2021covid19andtolllike pages 7-8)
Endogenous DAMP Oxidized lipoproteins and low-density-lipoprotein-related material Host lipoproteins modified during oxidative stress and atherosclerotic or metabolic injury; reported as endogenous TLR4-associated stimuli. (behzadi2021tolllikereceptorsgeneral pages 4-4, behzadi2021tolllikereceptorsgeneral pages 5-5)
Endogenous DAMP Amyloid-β and amyloid-related material Aggregated host peptides associated particularly with neurodegeneration; reported to activate microglial TLR4-associated inflammatory responses. (behzadi2021tolllikereceptorsgeneral pages 4-4, behzadi2021tolllikereceptorsgeneral pages 5-5)
Endogenous DAMP Mitochondrial DNA Organelle DNA released during mitochondrial damage or cell death; cited as a damage-associated nucleic-acid signal linked to TLR pathways, although direct TLR4 binding is less certain than for LPS. (sameer2021tolllikereceptors(tlrs) pages 3-5)
Endogenous DAMP Self-DNA, chromatin and endogenous nucleic-acid complexes Nuclear material released by injured or dying cells, sometimes complexed with HMGB1 or immunoglobulins; may amplify TLR4-associated inflammation indirectly, but assignment as a direct TLR4 ligand is context-dependent. (aboudounya2021covid19andtolllike pages 7-8, behzadi2021tolllikereceptorsgeneral pages 5-5)
Endogenous DAMP Plasma-membrane components and damage-derived membrane material Host membrane molecules released or exposed after cellular stress, injury, or death; broad DAMP category rather than a single chemically defined direct ligand. (sameer2021tolllikereceptors(tlrs) pages 3-5, kim2023tolllikereceptor4 pages 1-2)

Table: This table separates canonical microbial TLR4 ligands from host-derived danger signals and identifies each ligand’s source. It also distinguishes firmly established LPS–MD-2 recognition from proposed or context-dependent endogenous ligand assignments.

4. Subcellular Localization and Context of Function

TLR4 is initially expressed at the plasma membrane—often localizing to lipid rafts—where it binds LPS and activates MyD88-dependent (inflammatory) signaling. Upon activation, TLR4 undergoes endocytosis—a CD14-dependent process—into endosomes or phagosomes, where it triggers TRIF-dependent (interferon-producing) signaling (fitzgerald2020tolllikereceptorsand pages 2-3, sharma2025exploringtherole pages 4-5, valles2023tolllikereceptor4 pages 2-3, fitzgerald2020tolllikereceptorsand pages 7-8, stierschneider2023sheddinglighton pages 1-2). This location-dependent signaling enables TLR4 to orchestrate distinct innate immune responses from different cellular compartments.

5. TLR4 Signaling Pathways and Mechanisms

MyD88-Dependent Pathway (Cell Surface)

TRIF-Dependent Pathway (Endosomes)

A complete comparison of both signaling branches is presented below:
| Pathway name | Cellular signaling location | Key adaptor proteins | Downstream signaling molecules and kinases | Transcription factors activated | Major biological outcomes and products |
|---|---|---|---|---|---|
| MyD88-dependent pathway | Primarily the plasma membrane, including TLR4-enriched lipid rafts; initiates the early response after ligand-induced TLR4–MD-2 dimerization (fitzgerald2020tolllikereceptorsand pages 7-8, valles2023tolllikereceptor4 pages 2-3) | TIRAP/MAL bridges the TLR4 TIR domain to MyD88; MyD88 nucleates the Myddosome containing IRAK4 and IRAK1/2 (valles2023tolllikereceptor4 pages 2-3, luo2025anexaminationof pages 7-8) | IRAK4 → IRAK1/2 → TRAF6–Ubc13/Uev1A-mediated K63-linked polyubiquitin → TAK1–TAB1/2/3 → IKK complex and MAPKs (p38, JNK, ERK) (luo2025anexaminationof pages 7-8, stierschneider2023sheddinglighton pages 2-4) | NF-κB, AP-1, and context-dependently CREB (luo2025anexaminationof pages 7-8, stierschneider2023sheddinglighton pages 2-4) | Rapid inflammatory and host-defense gene expression; production of TNF, IL-1β, IL-6, chemokines, endothelial adhesion molecules, and costimulatory molecules; also primes inflammatory programs such as NLRP3 and pro-IL-1β expression (chen2025patternrecognitionreceptors pages 15-16, sameer2021tolllikereceptors(tlrs) pages 5-6) |
| TRIF-dependent (MyD88-independent) pathway | Activated principally after CD14-dependent TLR4 endocytosis into endosomes; produces a later signaling phase (fitzgerald2020tolllikereceptorsand pages 7-8, stierschneider2023sheddinglighton pages 2-4) | Endosomal TRAM/TICAM2 bridges TLR4 to TRIF/TICAM1, assembling a proposed Triffosome; TRAF3 and, for inflammatory signaling, TRAF6/RIP1 participate downstream (valles2023tolllikereceptor4 pages 2-3, fitzgerald2020tolllikereceptorsand pages 7-8, stierschneider2023sheddinglighton pages 2-4) | TRIF → TRAF3/TANK → TBK1 and IKKε for interferon signaling; TRIF can also engage TRAF6/RIP1 → TAK1 → IKK and MAPKs for late inflammatory signaling (sameer2021tolllikereceptors(tlrs) pages 5-6, stierschneider2023sheddinglighton pages 2-4, luo2025anexaminationof pages 4-7) | Predominantly IRF3; also late NF-κB and AP-1/MAPK-dependent factors (fitzgerald2020tolllikereceptorsand pages 7-8, stierschneider2023sheddinglighton pages 2-4) | Production of type I interferons, especially IFN-β, followed by interferon-stimulated genes; also contributes to delayed inflammatory cytokine expression. Under caspase-inhibited conditions, the TRIF RHIM domain can engage RIPK3-dependent necroptosis (valles2023tolllikereceptor4 pages 2-3, fitzgerald2020tolllikereceptorsand pages 7-8) |

Table: Comparison of the compartment-specific MyD88- and TRIF-dependent branches downstream of activated human TLR4, including adaptor complexes, kinase cascades, transcription factors, and principal immune outputs.

6. Recent Developments and Applications (2023-2025)

Structural Insights

Therapeutic Targeting

See the table of recent agents, mechanisms, diseases targeted, and development stages:
| Compound/agent | Mechanism of action | Disease applications | Development stage | Key findings/status |
|---|---|---|---|---|
| TAK-242 (resatorvid) | Small-molecule TLR4 antagonist; binds the intracellular TLR4 domain and inhibits adaptor-dependent signaling | Sepsis/endotoxemia, neuroinflammation, cerebral ischemia, myocardial ischemia–reperfusion injury | Clinical investigation for sepsis; otherwise preclinical | Reduced inflammatory mediators and improved survival or tissue outcomes in animal models. Nanoparticle delivery increased cardiac exposure and reduced infarct size, but systemic clinical development has not established efficacy. (xiao2020keyplayerin pages 12-14, tam2021tolllikereceptor4 pages 11-12, tam2021tolllikereceptor4 pages 10-11, tam2021tolllikereceptor4 pages 13-14) |
| Eritoran (E5564) | Synthetic lipid-A analogue and TLR4–MD-2 antagonist that competitively prevents agonistic LPS recognition | Severe sepsis, acute liver failure, renal ischemia–reperfusion injury; experimental cancer applications | Late-stage clinical development for sepsis; preclinical for other indications | Suppressed LPS-induced TNF and showed activity in animal models, but sepsis clinical development did not produce an established therapy; anticancer effects have been reported in murine colon-cancer models. (tam2021tolllikereceptor4 pages 10-11, tam2021tolllikereceptor4 pages 13-14, kashani2021theroleof pages 10-11) |
| FP7 | Synthetic glycolipid TLR4–MD-2 antagonist | Influenza-associated inflammation, inflammatory bowel disease, vascular inflammation | Preclinical | Suppressed LPS signaling and cytokine production; reduced pulmonary inflammatory genes and viral load in influenza models, vascular inflammation after angiotensin II, and disease severity in experimental colitis. (tam2021tolllikereceptor4 pages 11-12) |
| IAXO-102 | Synthetic TLR4 antagonist that inhibits TLR4-associated NF-κB and MAPK signaling | Abdominal aortic aneurysm and cardiovascular inflammation | Preclinical | Reduced JNK, ERK, p38 and NF-κB signaling, inflammatory mediators, TLR4 expression, and aneurysm incidence in experimental models. (tam2021tolllikereceptor4 pages 12-13, tam2021tolllikereceptor4 pages 11-12) |
| NI-0101 | Monoclonal anti-TLR4 antibody that blocks receptor activation | Systemic inflammatory and immune-mediated disorders | Clinical investigation | Entered registered clinical studies evaluating safety, pharmacology, and inflammatory-response suppression; no approved indication is established in the cited evidence. (tam2021tolllikereceptor4 pages 13-14) |
| AS04 | Licensed adjuvant containing the TLR4 agonist monophosphoryl lipid A (MPLA) adsorbed to an aluminum salt | Prophylactic human vaccination | Approved/licensed application | Demonstrates the principal successful clinical use of deliberate TLR4 activation: enhancing vaccine immunogenicity with a detoxified lipid-A derivative rather than native LPS. (sharma2025exploringtherole pages 4-5) |
| Neoseptin-3 and related neoseptins | Synthetic, non-lipid-A TLR4–MD-2 agonists with an alternative binding mode | Vaccine-adjuvant and immunostimulatory development | Preclinical | Two ligand molecules bind each TLR4–MD-2 heterodimer in distinct conformations; despite modest in-vitro potency, neoseptins showed useful in-vivo adjuvant activity. (tsukidate2023smallmoleculemodulators pages 2-4) |
| Disaccharide lipid-A mimetics (DLAM1, DLAM3, DLAM5) | Synthetic TLR4–MD-2 agonists that bridge and dimerize receptor complexes through binding modes distinct from natural LPS | Rationally designed vaccine adjuvants and immunotherapies | Preclinical/structural-development stage | Cryo-EM structures of six human or mouse complexes at 2.2–3.1 Å linked ligand-specific binding to receptor activation; cellular activity was tested across 0.01–1,000 nM, supporting species-independent agonist design. (fu2025structuralinsightinto pages 12-13) |
| Chalcone derivative compound 20 | Selective MD-2 inhibitor, indirectly antagonizing TLR4 activation | Acute lung injury | Preclinical | Reduced LPS-induced macrophage mediators, pulmonary edema, IL-1β secretion, and myeloperoxidase activity in rats. (tam2021tolllikereceptor4 pages 12-13) |
| L48H37 | Curcumin analogue and MD-2 inhibitor that suppresses TLR4-linked MAPK signaling | Septic shock and acute lung injury | Preclinical | Reduced MAPK phosphorylation and inflammatory cytokines and improved survival and lung pathology in LPS-challenged mice. (tam2021tolllikereceptor4 pages 12-13) |
| CRX-526 | Synthetic lipid-A mimetic functioning as a TLR4 antagonist/modulator | Inflammatory bowel disease | Preclinical | Dose-dependently reduced disease-activity and histological scores in DSS-induced colitis. (tam2021tolllikereceptor4 pages 12-13) |
| T5342126 | Small molecule that disrupts the TLR4–MD-2 interaction | Pathological cardiac hypertrophy and cardiovascular inflammation | Preclinical | Proposed to attenuate receptor-complex formation and downstream inflammatory remodeling; evidence remains experimental. (xiao2020keyplayerin pages 12-14) |
| Compound 8a | Small-molecule antagonist targeting the LPS–TLR4–MD-2 complex | Cardiac and other inflammatory disorders | Preclinical | Produced anti-inflammatory effects in experimental studies by interfering with the ligand–receptor complex. (xiao2020keyplayerin pages 12-14) |
| HMGB1 Box A | Competitive inhibitor of the endogenous TLR4-associated danger signal HMGB1 | Pressure-overload cardiac hypertrophy and heart failure | Preclinical | Reversed hypertrophic remodeling and delayed heart-failure progression in experimental models, illustrating ligand-directed rather than receptor-directed blockade. (xiao2020keyplayerin pages 12-14) |
| Paeoniflorin and other phytochemicals | Indirect TLR4-pathway inhibitors that reduce receptor expression or downstream NF-κB/MAPK signaling | Inflammatory bowel disease and intestinal inflammation | Preclinical | Improved experimental colitis outcomes, but the broader phytochemical literature remains dominated by cell and animal studies with limited clinical validation. (dai2022phytochemicalstargetingtolllike pages 1-2, tam2021tolllikereceptor4 pages 10-11) |
| TLR4-targeting siRNA/shRNA | Genetic TLR4 knockdown | Ovarian, breast, prostate, oral, colon and pancreatic cancers; acute myeloid leukemia | Preclinical | Increased tumor-cell apoptosis and sensitivity to paclitaxel, cisplatin, doxorubicin, docetaxel and arsenic trioxide in experimental systems. (kashani2021theroleof pages 10-11) |

Table: Summary of TLR4 agonists, antagonists, coreceptor inhibitors, and genetic interventions investigated from 2020–2025. The table distinguishes approved applications from clinical and preclinical programs and highlights their mechanisms and principal findings.

7. Expert Consensus and Analysis

8. Relevant Statistics and Data

9. URLs and Sources (selective)

For more detailed references, please consult the citation codes within summary tables and throughout this report.

References

  1. (kashani2021theroleof pages 1-2): Bahareh Kashani, Zahra Zandi, Atieh Pourbagheri‐Sigaroodi, Davood Bashash, and Seyed H. Ghaffari. The role of toll‐like receptor 4 (tlr4) in cancer progression: a possible therapeutic target? Journal of Cellular Physiology, 236:4121-4137, Nov 2021. URL: https://doi.org/10.1002/jcp.30166, doi:10.1002/jcp.30166. This article has 116 citations and is from a peer-reviewed journal.

  2. (sameer2021tolllikereceptors(tlrs) pages 3-5): Aga Syed Sameer and Saniya Nissar. Toll-like receptors (tlrs): structure, functions, signaling, and role of their polymorphisms in colorectal cancer susceptibility. BioMed Research International, Sep 2021. URL: https://doi.org/10.1155/2021/1157023, doi:10.1155/2021/1157023. This article has 517 citations.

  3. (behzadi2021tolllikereceptorsgeneral pages 12-13): Payam Behzadi, Herney Andrés García-Perdomo, and Tomasz M. Karpiński. Toll-like receptors: general molecular and structural biology. Journal of Immunology Research, 2021:1-21, May 2021. URL: https://doi.org/10.1155/2021/9914854, doi:10.1155/2021/9914854. This article has 333 citations and is from a peer-reviewed journal.

  4. (luo2025anexaminationof pages 2-4): Ruiqin Luo, Yuexin Yao, Zhuo Chen, and Xiaoming Sun. An examination of the lps-tlr4 immune response through the analysis of molecular structures and protein–protein interactions. Cell Communication and Signaling : CCS, Mar 2025. URL: https://doi.org/10.1186/s12964-025-02149-4, doi:10.1186/s12964-025-02149-4. This article has 219 citations.

  5. (sameer2021tolllikereceptors(tlrs) pages 2-3): Aga Syed Sameer and Saniya Nissar. Toll-like receptors (tlrs): structure, functions, signaling, and role of their polymorphisms in colorectal cancer susceptibility. BioMed Research International, Sep 2021. URL: https://doi.org/10.1155/2021/1157023, doi:10.1155/2021/1157023. This article has 517 citations.

  6. (stierschneider2023sheddinglighton pages 1-2): Anna Stierschneider and Christoph Wiesner. Shedding light on the molecular and regulatory mechanisms of tlr4 signaling in endothelial cells under physiological and inflamed conditions. Frontiers in Immunology, Nov 2023. URL: https://doi.org/10.3389/fimmu.2023.1264889, doi:10.3389/fimmu.2023.1264889. This article has 79 citations and is from a peer-reviewed journal.

  7. (luo2025anexaminationof pages 1-2): Ruiqin Luo, Yuexin Yao, Zhuo Chen, and Xiaoming Sun. An examination of the lps-tlr4 immune response through the analysis of molecular structures and protein–protein interactions. Cell Communication and Signaling : CCS, Mar 2025. URL: https://doi.org/10.1186/s12964-025-02149-4, doi:10.1186/s12964-025-02149-4. This article has 219 citations.

  8. (kim2023tolllikereceptor4 pages 2-3): Hyo-Jin Kim, Hyemin Kim, Jeong-Hyung Lee, and Cheol Hwangbo. Toll-like receptor 4 (tlr4): new insight immune and aging. Immunity & Ageing : I & A, Nov 2023. URL: https://doi.org/10.1186/s12979-023-00383-3, doi:10.1186/s12979-023-00383-3. This article has 568 citations.

  9. (aboudounya2021covid19andtolllike pages 7-8): Mohamed M. Aboudounya and Richard J. Heads. Covid-19 and toll-like receptor 4 (tlr4): sars-cov-2 may bind and activate tlr4 to increase ace2 expression, facilitating entry and causing hyperinflammation. Mediators of Inflammation, 2021:1-18, Jan 2021. URL: https://doi.org/10.1155/2021/8874339, doi:10.1155/2021/8874339. This article has 445 citations and is from a peer-reviewed journal.

  10. (xiao2020keyplayerin pages 4-5): Zheng Xiao, Bin Kong, Hong-Jie Yang, Chang-Feng Dai, Jin Fang, Tianyou Qin, and He Huang. Key player in cardiac hypertrophy, emphasizing the role of toll-like receptor 4. Frontiers in Cardiovascular Medicine, Nov 2020. URL: https://doi.org/10.3389/fcvm.2020.579036, doi:10.3389/fcvm.2020.579036. This article has 59 citations and is from a peer-reviewed journal.

  11. (tominari2024rolesoftolllike pages 6-7): Tsukasa Tominari, Chiho Matsumoto, Yuki Tanaka, Kensuke Shimizu, Masaru Takatoya, Moe Sugasaki, Kento Karouji, Urara Kasuga, Chisato Miyaura, Shinji Miyata, Yoshifumi Itoh, Michiko Hirata, and Masaki Inada. Roles of toll-like receptor signaling in inflammatory bone resorption. Biology, 13:692, Sep 2024. URL: https://doi.org/10.3390/biology13090692, doi:10.3390/biology13090692. This article has 49 citations.

  12. (behzadi2021tolllikereceptorsgeneral pages 4-4): Payam Behzadi, Herney Andrés García-Perdomo, and Tomasz M. Karpiński. Toll-like receptors: general molecular and structural biology. Journal of Immunology Research, 2021:1-21, May 2021. URL: https://doi.org/10.1155/2021/9914854, doi:10.1155/2021/9914854. This article has 333 citations and is from a peer-reviewed journal.

  13. (kim2023tolllikereceptor4 pages 1-2): Hyo-Jin Kim, Hyemin Kim, Jeong-Hyung Lee, and Cheol Hwangbo. Toll-like receptor 4 (tlr4): new insight immune and aging. Immunity & Ageing : I & A, Nov 2023. URL: https://doi.org/10.1186/s12979-023-00383-3, doi:10.1186/s12979-023-00383-3. This article has 568 citations.

  14. (tsukidate2023smallmoleculemodulators pages 2-4): Taku Tsukidate, Charles W. Hespen, and Howard C. Hang. Small molecule modulators of immune pattern recognition receptors. RSC Chemical Biology, 4:1014-1036, Oct 2023. URL: https://doi.org/10.1039/d3cb00096f, doi:10.1039/d3cb00096f. This article has 23 citations and is from a peer-reviewed journal.

  15. (behzadi2021tolllikereceptorsgeneral pages 5-5): Payam Behzadi, Herney Andrés García-Perdomo, and Tomasz M. Karpiński. Toll-like receptors: general molecular and structural biology. Journal of Immunology Research, 2021:1-21, May 2021. URL: https://doi.org/10.1155/2021/9914854, doi:10.1155/2021/9914854. This article has 333 citations and is from a peer-reviewed journal.

  16. (fitzgerald2020tolllikereceptorsand pages 2-3): Katherine A. Fitzgerald and Jonathan C. Kagan. Toll-like receptors and the control of immunity. Cell, 180:1044-1066, Mar 2020. URL: https://doi.org/10.1016/j.cell.2020.02.041, doi:10.1016/j.cell.2020.02.041. This article has 2632 citations and is from a highest quality peer-reviewed journal.

  17. (sharma2025exploringtherole pages 4-5): Meenal Sharma, Priyanka Wagh, Tanvi Shinde, Diptee Trimbake, and Anuradha S. Tripathy. Exploring the role of pattern recognition receptors as immunostimulatory molecules. Immunity, Inflammation and Disease, May 2025. URL: https://doi.org/10.1002/iid3.70150, doi:10.1002/iid3.70150. This article has 17 citations and is from a peer-reviewed journal.

  18. (valles2023tolllikereceptor4 pages 2-3): Patricia G. Vallés, Andrea Fernanda Gil Lorenzo, Rodrigo D. Garcia, Valeria Cacciamani, María Eugenia Benardon, and Valeria Victoria Costantino. Toll-like receptor 4 in acute kidney injury. International Journal of Molecular Sciences, 24:1415, Jan 2023. URL: https://doi.org/10.3390/ijms24021415, doi:10.3390/ijms24021415. This article has 81 citations.

  19. (fitzgerald2020tolllikereceptorsand pages 7-8): Katherine A. Fitzgerald and Jonathan C. Kagan. Toll-like receptors and the control of immunity. Cell, 180:1044-1066, Mar 2020. URL: https://doi.org/10.1016/j.cell.2020.02.041, doi:10.1016/j.cell.2020.02.041. This article has 2632 citations and is from a highest quality peer-reviewed journal.

  20. (chen2025patternrecognitionreceptors pages 15-16): Ruochan Chen, Juqiu Zou, Jiawang Chen, Xiao Zhong, Rui Kang, and Daolin Tang. Pattern recognition receptors: function, regulation and therapeutic potential. Signal Transduction and Targeted Therapy, Jul 2025. URL: https://doi.org/10.1038/s41392-025-02264-1, doi:10.1038/s41392-025-02264-1. This article has 419 citations and is from a peer-reviewed journal.

  21. (sameer2021tolllikereceptors(tlrs) pages 5-6): Aga Syed Sameer and Saniya Nissar. Toll-like receptors (tlrs): structure, functions, signaling, and role of their polymorphisms in colorectal cancer susceptibility. BioMed Research International, Sep 2021. URL: https://doi.org/10.1155/2021/1157023, doi:10.1155/2021/1157023. This article has 517 citations.

  22. (luo2025anexaminationof pages 7-8): Ruiqin Luo, Yuexin Yao, Zhuo Chen, and Xiaoming Sun. An examination of the lps-tlr4 immune response through the analysis of molecular structures and protein–protein interactions. Cell Communication and Signaling : CCS, Mar 2025. URL: https://doi.org/10.1186/s12964-025-02149-4, doi:10.1186/s12964-025-02149-4. This article has 219 citations.

  23. (stierschneider2023sheddinglighton pages 2-4): Anna Stierschneider and Christoph Wiesner. Shedding light on the molecular and regulatory mechanisms of tlr4 signaling in endothelial cells under physiological and inflamed conditions. Frontiers in Immunology, Nov 2023. URL: https://doi.org/10.3389/fimmu.2023.1264889, doi:10.3389/fimmu.2023.1264889. This article has 79 citations and is from a peer-reviewed journal.

  24. (luo2025anexaminationof pages 4-7): Ruiqin Luo, Yuexin Yao, Zhuo Chen, and Xiaoming Sun. An examination of the lps-tlr4 immune response through the analysis of molecular structures and protein–protein interactions. Cell Communication and Signaling : CCS, Mar 2025. URL: https://doi.org/10.1186/s12964-025-02149-4, doi:10.1186/s12964-025-02149-4. This article has 219 citations.

  25. (fu2025structuralinsightinto pages 12-13): Yaoyao Fu, Hyojin Kim, Dong Sun Lee, Ah-reum Han, Holger Heine, Alla Zamyatina, and Ho Min Kim. Structural insight into tlr4/md-2 activation by synthetic lps mimetics with distinct binding modes. Nature Communications, May 2025. URL: https://doi.org/10.1038/s41467-025-59550-3, doi:10.1038/s41467-025-59550-3. This article has 44 citations and is from a highest quality peer-reviewed journal.

  26. (bzowka2023recentadvancesin pages 11-12): Maria Bzówka, Weronika Bagrowska, and Artur Góra. Recent advances in studying toll-like receptors with the use of computational methods. Journal of Chemical Information and Modeling, 63:3669-3687, Jun 2023. URL: https://doi.org/10.1021/acs.jcim.3c00419, doi:10.1021/acs.jcim.3c00419. This article has 34 citations and is from a peer-reviewed journal.

  27. (tam2021tolllikereceptor4 pages 12-13): Janine S. Y. Tam, Janet K. Coller, Patrick A. Hughes, Clive A. Prestidge, and Joanne M. Bowen. Toll-like receptor 4 (tlr4) antagonists as potential therapeutics for intestinal inflammation. Indian Journal of Gastroenterology, 40:5-21, Feb 2021. URL: https://doi.org/10.1007/s12664-020-01114-y, doi:10.1007/s12664-020-01114-y. This article has 107 citations and is from a peer-reviewed journal.

  28. (xiao2020keyplayerin pages 12-14): Zheng Xiao, Bin Kong, Hong-Jie Yang, Chang-Feng Dai, Jin Fang, Tianyou Qin, and He Huang. Key player in cardiac hypertrophy, emphasizing the role of toll-like receptor 4. Frontiers in Cardiovascular Medicine, Nov 2020. URL: https://doi.org/10.3389/fcvm.2020.579036, doi:10.3389/fcvm.2020.579036. This article has 59 citations and is from a peer-reviewed journal.

  29. (tam2021tolllikereceptor4 pages 10-11): Janine S. Y. Tam, Janet K. Coller, Patrick A. Hughes, Clive A. Prestidge, and Joanne M. Bowen. Toll-like receptor 4 (tlr4) antagonists as potential therapeutics for intestinal inflammation. Indian Journal of Gastroenterology, 40:5-21, Feb 2021. URL: https://doi.org/10.1007/s12664-020-01114-y, doi:10.1007/s12664-020-01114-y. This article has 107 citations and is from a peer-reviewed journal.

  30. (tam2021tolllikereceptor4 pages 13-14): Janine S. Y. Tam, Janet K. Coller, Patrick A. Hughes, Clive A. Prestidge, and Joanne M. Bowen. Toll-like receptor 4 (tlr4) antagonists as potential therapeutics for intestinal inflammation. Indian Journal of Gastroenterology, 40:5-21, Feb 2021. URL: https://doi.org/10.1007/s12664-020-01114-y, doi:10.1007/s12664-020-01114-y. This article has 107 citations and is from a peer-reviewed journal.

  31. (kashani2021theroleof pages 10-11): Bahareh Kashani, Zahra Zandi, Atieh Pourbagheri‐Sigaroodi, Davood Bashash, and Seyed H. Ghaffari. The role of toll‐like receptor 4 (tlr4) in cancer progression: a possible therapeutic target? Journal of Cellular Physiology, 236:4121-4137, Nov 2021. URL: https://doi.org/10.1002/jcp.30166, doi:10.1002/jcp.30166. This article has 116 citations and is from a peer-reviewed journal.

  32. (tam2021tolllikereceptor4 pages 11-12): Janine S. Y. Tam, Janet K. Coller, Patrick A. Hughes, Clive A. Prestidge, and Joanne M. Bowen. Toll-like receptor 4 (tlr4) antagonists as potential therapeutics for intestinal inflammation. Indian Journal of Gastroenterology, 40:5-21, Feb 2021. URL: https://doi.org/10.1007/s12664-020-01114-y, doi:10.1007/s12664-020-01114-y. This article has 107 citations and is from a peer-reviewed journal.

  33. (dai2022phytochemicalstargetingtolllike pages 1-2): Wenbin Dai, Longhai Long, Xiaoqiang Wang, Sen Li, and Houping Xu. Phytochemicals targeting toll-like receptors 4 (tlr4) in inflammatory bowel disease. Chinese Medicine, Apr 2022. URL: https://doi.org/10.1186/s13020-022-00611-w, doi:10.1186/s13020-022-00611-w. This article has 59 citations.

Artifacts

Citations

  1. stierschneider2023sheddinglighton pages 1-2
  2. kashani2021theroleof pages 1-2
  3. behzadi2021tolllikereceptorsgeneral pages 5-5
  4. sharma2025exploringtherole pages 4-5
  5. tsukidate2023smallmoleculemodulators pages 2-4
  6. fu2025structuralinsightinto pages 12-13
  7. xiao2020keyplayerin pages 12-14
  8. kashani2021theroleof pages 10-11
  9. behzadi2021tolllikereceptorsgeneral pages 12-13
  10. luo2025anexaminationof pages 2-4
  11. luo2025anexaminationof pages 1-2
  12. xiao2020keyplayerin pages 4-5
  13. tominari2024rolesoftolllike pages 6-7
  14. behzadi2021tolllikereceptorsgeneral pages 4-4
  15. fitzgerald2020tolllikereceptorsand pages 2-3
  16. fitzgerald2020tolllikereceptorsand pages 7-8
  17. chen2025patternrecognitionreceptors pages 15-16
  18. luo2025anexaminationof pages 7-8
  19. stierschneider2023sheddinglighton pages 2-4
  20. luo2025anexaminationof pages 4-7
  21. bzowka2023recentadvancesin pages 11-12
  22. dai2022phytochemicalstargetingtolllike pages 1-2
  23. https://doi.org/10.1186/s12979-023-00383-3
  24. https://doi.org/10.1016/j.cell.2020.02.041
  25. https://doi.org/10.1186/s12964-025-02149-4
  26. https://doi.org/10.3390/ijms24021415
  27. https://doi.org/10.1007/s12664-020-01114-y
  28. https://doi.org/10.1038/s41467-025-59550-3
  29. https://doi.org/10.1186/s12979-023-00383-3](https://doi.org/10.1186/s12979-023-00383-3
  30. https://doi.org/10.1016/j.cell.2020.02.041](https://doi.org/10.1016/j.cell.2020.02.041
  31. https://doi.org/10.1186/s12964-025-02149-4](https://doi.org/10.1186/s12964-025-02149-4
  32. https://doi.org/10.3390/ijms24021415](https://doi.org/10.3390/ijms24021415
  33. https://doi.org/10.1007/s12664-020-01114-y](https://doi.org/10.1007/s12664-020-01114-y
  34. https://doi.org/10.1038/s41467-025-59550-3](https://doi.org/10.1038/s41467-025-59550-3
  35. https://doi.org/10.1002/jcp.30166,
  36. https://doi.org/10.1155/2021/1157023,
  37. https://doi.org/10.1155/2021/9914854,
  38. https://doi.org/10.1186/s12964-025-02149-4,
  39. https://doi.org/10.3389/fimmu.2023.1264889,
  40. https://doi.org/10.1186/s12979-023-00383-3,
  41. https://doi.org/10.1155/2021/8874339,
  42. https://doi.org/10.3389/fcvm.2020.579036,
  43. https://doi.org/10.3390/biology13090692,
  44. https://doi.org/10.1039/d3cb00096f,
  45. https://doi.org/10.1016/j.cell.2020.02.041,
  46. https://doi.org/10.1002/iid3.70150,
  47. https://doi.org/10.3390/ijms24021415,
  48. https://doi.org/10.1038/s41392-025-02264-1,
  49. https://doi.org/10.1038/s41467-025-59550-3,
  50. https://doi.org/10.1021/acs.jcim.3c00419,
  51. https://doi.org/10.1007/s12664-020-01114-y,
  52. https://doi.org/10.1186/s13020-022-00611-w,