Molecular biology and immunology for clinicians 20: Angiogenesis and vascular growth factors and signals.

If we accept the perfectly reasonable premise that the mass of inflammatory tissue in rheumatoid arthritis (and psoriatic arthritis or any other inflammatory joint disease) requires oxygen and nutrition to survive and grow, we are confronted with a novel concept for therapy: if we can block the nutritional supply of the pannus, we can suppress or prevent its growth and the subsequent destruction of the joint. Thus, an understanding of how new blood vessels nourish the inflammatory mass could be pivotal in successfully treating our patients. Angiogenesis is the process whereby new blood vessels enter the site of inflammation or growing malignancy to supply the invading tissue. Many growth factors and local tissue conditions help to determine blood vessel growth, there being pro- and anti-angiogenetic influences. Thus, this is fertile ground for therapeutic molecular manipulations.