Related Experiment Video

Updated: Jul 12, 2026

An Adoptive Transfer Model of Rheumatoid Arthritis in Mice
07:37

An Adoptive Transfer Model of Rheumatoid Arthritis in Mice

Published on: June 6, 2025

Inhibition of Toll-like receptor 4 breaks the inflammatory loop in autoimmune destructive arthritis

Shahla Abdollahi-Roodsaz1, Leo A B Joosten, Mieke F Roelofs

  • 1Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands. s.abdollahi-roodsaz@reuma.umcn.nl

Arthritis and Rheumatism
|September 1, 2007
PubMed
Abstract

Insights

Toll-like receptor 4 (TLR-4) activation contributes to autoimmune arthritis. Inhibiting TLR-4 with a novel antagonist significantly reduced joint inflammation and pathology in experimental models, suggesting TLR-4 as a potential therapeutic target.

Area of Science:

  • Immunology
  • Rheumatology
  • Molecular Biology

Background:

  • Cartilage degeneration releases molecules activating Toll-like receptor 4 (TLR-4).
  • TLR-4 activation is implicated in the immune system's response during destructive arthritis.

Purpose of the Study:

  • To investigate the role of TLR-4 activation in the development and progression of autoimmune destructive arthritis.
  • To evaluate a novel TLR-4 antagonist for its therapeutic potential in arthritis models.

Main Methods:

  • Characterized a natural TLR-4 antagonist (LPS from Bartonella quintana) using macrophages and dendritic cells (DCs).
  • Treated mice with collagen-induced arthritis (CIA) and IL-1 receptor antagonist (IL-1Ra) gene-deficient spontaneous arthritis with the TLR-4 antagonist.
  • Assessed clinical scores, histological features, and IL-1 expression in joints.

Main Results:

  • The TLR-4 antagonist inhibited DC maturation and cytokine production without intrinsic activity.
  • Treatment suppressed clinical and histological signs of CIA without affecting adaptive immunity.
  • Reduced IL-1beta expression in joints and protected against cartilage and bone damage in IL-1Ra(-/-) mice.

Conclusions:

  • TLR-4 inhibition effectively suppresses experimental arthritis severity and reduces joint IL-1 expression.
  • TLR-4 represents a promising novel therapeutic target for rheumatoid arthritis treatment.

Related Concept Videos

T Cell Types and Functions01:24

T Cell Types and Functions

When T cells with CD4 markers are activated, they give rise to two types of effector cells: helper T cells and regulatory T cells. Meanwhile, T cells with CD8 markers differentiate into effector cytotoxic T cells. The differentiation of CD4 T cells into helper T cell subsets, such as Th1, Th2, and Th17 cells, is dependent on the antigen type, antigen-presenting cell, and regulatory cytokines.
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
The JAK-STAT Signaling Pathway01:20

The JAK-STAT Signaling Pathway

Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as  SH2...
Inflammatory Response01:28

Inflammatory Response

An inflammatory response is a localized, nonspecific immune reaction that occurs when a tissue is injured. It is characterized by redness, swelling, heat, and pain, which are commonly called the cardinal signs and symptoms of inflammation. Inflammation can sometimes result in a loss of function.
Inflammation can be triggered by various stimuli, such as impact, abrasion, chemical irritation, infections, and extreme hot or cold temperatures. These can damage cells and connective tissue fibers,...
Inflammatory Bowel Disease III: Crohn's Disease01:25

Inflammatory Bowel Disease III: Crohn's Disease

Crohn’s disease is a chronic, relapsing form of inflammatory bowel disease characterized by segmental, transmural inflammation that can affect any part of the gastrointestinal tract. Its pathogenesis arises from a combination of genetic susceptibility, environmental exposures, epithelial barrier dysfunction, and immune dysregulation. Together, these factors lead to an exaggerated immune response against components of the gut microbiome.Genetic and Environmental InfluencesMultiple genetic...
Drugs for Treatment of Crohn's Disease in IBD Using Biologic Agents: Anti-TNF01:24

Drugs for Treatment of Crohn's Disease in IBD Using Biologic Agents: Anti-TNF

Tumor Necrosis Factor (TNF), a proinflammatory cytokine, contributes significantly to the inflammation seen in Crohn's disease. It exists as soluble TNF and membrane-bound TNF, with actions mediated through TNF receptors (TNFR). TNFR activation leads to the release of proinflammatory cytokines, T-cell activation, collagen production, and leukocyte migration, all contributing to inflammation in Crohn's disease. Anti-TNF monoclonal antibodies, namely infliximab (Remicade), adalimumab (Humira),...
Inflammatory Bowel Disease II: Ulcerative Colitis01:20

Inflammatory Bowel Disease II: Ulcerative Colitis

Ulcerative colitis is a chronic inflammatory disorder of the colon characterized by continuous mucosal inflammation that typically begins in the rectum and extends proximally in a uniform pattern. Its pathogenesis involves a complex interplay of genetic predisposition, immune dysregulation, and environmental influences. These factors converge to impair the colon’s epithelial defenses and promote an exaggerated inflammatory response against luminal contents.Breakdown of the Mucosal BarrierA...