Targeting Angiogenesis in Rheumatoid Arthritis.

Angiogenesis, the development of new capillaries, is a crucial process in health and disease. The perpetuation of neovascularization in rheumatoid arthritis is highly involved in leukocyte extravasation into the synovium and pannus formation. Numerous soluble and cell surface-bound angiogenic mediators, including growth factors, cytokines, proteases, matrix macromolecules, cell adhesion receptors, chemokines and chemokine receptors, have been implicated in the process of neovascularization. Endogenous angiostatic factors, primarily angiostatin, endostatin, IL-4, IL-13, some angiostatic chemokines may be used to downregulate neovascularization. In addition, angiogenesis might be targeted by several specific approaches against VEGF, angiopoietin, α(v)β(3) integrin or by exogenously administered compounds including DMARDs, anti-TNF agents, fumagillin analogues or thalidomide. Potentially all anti-angiogenic could be tried in order to control synovitis.