TLR9 and rheumatoid arthritis: It has also been linked to decreasedjoint inflammation.182 A monoclonal antibodyagainst TLR-2, OPN301, can reduce proinflammatory cytokines in thesynovium tissue.183 Interestingly, Hydroxychloroquine,used to treat RA, downregulates TLR-9-mediated differentiation ofB cells.180 In conclusion, a deep understandingof the TLRs found in the synovium of RA patients may open new doorsfor novel RA therapeutic approaches.