Role of tumor necrosis factor‐alpha in rheumatoid arthritis: a review

Tumor necrosis factor‐alpha (TNF‐α) is a proinflammatory cytokine that plays a pivotal role in regulating the inflammatory response in rheumatoid arthritis (RA). Although it is controversial whether TNF‐α genes are associated with RA susceptibility, they are well known to mediate RA pathogenesis. We review in depth the history, formation and biological action, TNF receptor, role in mediating pathogenesis in RA and mode of action, of anti‐TNF‐α drugs.