A 30-year-old woman presents with morning stiffness lasting over an hour, symmetrical small joint swelling of both hands, and elevated anti-CCP antibodies. Synovial biopsy shows villous hypertrophy, lining cell hyperplasia (pannus formation), and dense lymphoplasmacytic infiltrate. Which cytokine is the primary mediator of synovial destruction in this disease?
- A IL-4
- B TNF-alpha ✓
- C IL-10
- D TGF-beta
Correct answer: B. TNF-alpha
Explanation
Rheumatoid arthritis is characterized by chronic synovial inflammation driven largely by TNF-alpha secreted by activated macrophages and T-cells in the pannus. TNF-alpha upregulates adhesion molecules, stimulates synoviocyte proliferation, induces IL-1 and IL-6 production, and activates osteoclasts leading to marginal bone erosion. This is the basis for highly effective TNF-alpha blockade therapies (infliximab, etanercept). Anti-CCP antibodies have high specificity for RA and predict erosive disease.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.