Anti-TNFα Therapy of Rheumatoid Arthritis: What Have We Learned?

Abstract
Rheumatoid arthritis (RA), a systemic disease, is characterized by a chronic inflammatory reaction in the synovium of joints and is associated with degeneration of cartilage and erosion of juxta-articular bone. Many pro-inflammatory cytokines including TNFα, chemokines, and growth factors are expressed in diseased joints. The rationale that TNFα played a central role in regulating these molecules, and their pathophysiological potential, was initially provided by the demonstration that anti-TNFα antibodies added to in vitro cultures of a representative population of cells derived from diseased joints inhibited the spontaneous production of IL-1 and other pro-inflammatory cytokines. Systemic administration of anti-TNFα antibody or sTNFR fusion protein to mouse models of RA was shown to be anti-inflammatory and joint protective. Clinical investigations in which the activcity of TNFα in RA patients was blocked with intravenously administered infliximab, a chimeric anti-TNFα monoclonal antibody (mAB), has prov...