Cytokines in arthritis--the 'big numbers' move centre stage.

摘要

More than 20 yrs ago, T-helper lymphocytes were divided into Th1 and Th2 subsets on the basis of their cytokine production. The pro-inflammatory Th1 subset was considered predominant in inflammatory arthritis, but evidence for this notion was incomplete, and some called into question the role of helper T cells. The identification of a novel T cell subset, Th17 cells, which appears to be critical for several forms of autoimmune inflammation, including arthritis, requires a reconsideration of arthritis pathogenesis and the role of T cells. This review deals with several of the newly described ('big number') cytokines which are involved in the differentiation and action of Th17 cells, and pays particular attention to the pathogenesis of spondyloarthritis because of the implication of the same cytokine networks in psoriasis and inflammatory bowel disease. The role of dendritic cells as coordinators of T cell differentiation in response to pathogen-derived signals in also emphasized.