Platelet-derived growth factor (PDGF) is one of the numerous growth factors that regulate cell growth and division. In particular, it plays a significant role in blood vessel formation (angiogenesis), the growth of blood vessels from already-existing blood vessel tissue. Uncontrolled angiogenesis is a characteristic of cancer. In chemical terms, PDGF is a dimeric glycoprotein composed of two A (-AA) or two B (-BB) chains or a combination of the two (-AB).
PDGF-BB is expressed by hepatocytes and nonresorbing osteoclasts, generating osteoblasts and bone formation. It is also produced by platelets, macrophages, and mast cells, and at sites of injury, promotes neutrophil and macrophage infiltration for debridement, fibroblast secretion of new ECM, and IFG-1 mediated re-epithelialization.