The role of IL-17 in joint destruction

Interleukin-17 (IL-17) is a recently cloned cytokine secreted by activated memory CD4(+) T cells and modulates the early stage of immune responses. IL-17 stimulates epithelial, endothelial and fibroblastic stromal cells to secrete several cytokines such as IL-6, IL-8 and granulocyte colony-stimulating factor, as well as prostoglandin E2. IL-17 also stimulates the production and expression of proinflammatory cytokines, IL-1beta and tumor necrosis factor-alpha by human macrophages. IL-17 may be involved in osteoclastic bone resorption in rheumatoid arthritis patients. Recently, several groups have reported that IL-17 plays important roles in both the immune response and joint destruction in patients with rheumatoid arthritis. The control of IL-17 expression in these patients could provide directions for the development of new treatment strategies for joint destruction. (C) 2002 Prous Science. All rights reserved.