Angiogenesis: general mechanisms and implications for rheumatoid arthritis

In rheumatoid arthritis, the vascular endothelium is among the key targets for circulating mediators of inflammation and controls the trafficking of c ells and molecules from the bloodstream: toward the synovial tissue. Local blood vessel proliferation allows the pannus to develop and grow, thereby p romoting cartilage and bone destruction and joint remodeling. Angiogenesis, the production of new capillaries from preexisting blood vessels, is a key process in rheumatoid arthritis that involves multiple substances such as cytokines, chemokines, growth factors, cell adhesion molecules, proteinases , proteinase inhibitors, and matrix proteins. in animal models of arthritis , angiogenesis inhibitors have been found to im prove clinical and radiolog ical outcomes, opening up the possibility of therapeutic applications in hu mans. Before this possibility is realized, the steady accumulation of data on the mechanisms that regulate angiogenesis wilt have to continue until a clear picture of angiogenesis is formed. (C) 2000 Editions scientifiques et medicales Elsevier SAS.