Introduction. CXCR6 is highly expressed on lymphocytes isolated from the synovium of patients with rheumatoid or psoriatic arthritis, suggesting that CXCR6 could be important in mediating the infiltration of immune cells into arthritic joints.; Methods. We used the collagen-induced arthritis (CIA) model to examine the role of CXCR6 in joint inflammation. Arthritis in wild type and CXCR6-/- mice was assessed in a blinded manner by measuring paw thickness and clinical scores.; Results. CXCR6-/- mice exhibited a decreased incidence and severity of arthritis compared with wild type mice. A few CXCR6-/- mice exhibited a mild and transient increase in joint swelling. Following collagen immunization, there were no apparent differences in the induction of memory CD4+ and CD8 + T cells in wild-type and CXCR6-/- mice at ∼day 24. At 80 days plus however a significant decrease in memory cells was found in the popliteal lymph nodes of the CXCR6-deficient mice compared to the wild type mice. The CXCR6-/- also exhibited a decrease in IFN-gamma production, suggesting an impaired TH1 response which is important for arthritis development.; Conclusions. Our experiments show that CXCR6 plays an important role in the joint inflammation observed in collagen-induced arthritis. CXCR6 could be playing roles in lymphocyte recruitment or lymphocyte activation. We will perform adoptive transfers to identify whether CXCR6 plays a direct role in lymphocyte homing to the inflamed joint.
展开▼
