Expression of Toll‐like receptors 2 and 4 in rheumatoid synovial tissue and regulation by proinflammatory cytokines interleukin‐12 and interleukin‐18 via interferon‐γ

TLR-2 and TLR-4 are expressed in synovial tissue of patients with clinically active disease and are associated with the levels of both IL-12 and IL-18. The synergistic effect of IL-12 and IL-18 on T cell IFNgamma production seems to regulate expression of TLR-2 and TLR-4 in the synovial tissue of RA patients.