The neutrophil in rheumatoid arthritis.

The destructive capacity of the neutrophil has long been appreciated, and the presence of extraordinary numbers of neutrophils in the synovial fluid of patients with RA supports a role for these cells in the pathogenesis of joint destruction. In this article, we reviewed the current state of knowledge of neutrophil function in the inflammatory response, and emphasized the subjects of neutrophil/endothelial adhesion and the role of chemoattractants and cytokines in neutrophil mobilization. We also discussed the mechanisms of action of neutrophil destruction of cartilage and the interplay of signals between the neutrophil and the chondrocyte. The capacity of many of the drugs used to treat RA to interfere with one or several of these processes underscores the importance of the neutrophil in RA and suggests that future therapeutic strategies could target neutrophil activation within the synovial space.