General Medical Information

Platelet-derived Growth Factor

David J. Terris

PDGF is a glycoprotein composed of two chains (a and b) resulting in three different dimeric forms of PDGF (PDGF-AB, PDGF-AA, and PDGF-BB). As with many of the other cytokines, interaction with the PDGF receptor results in activation of the tyrosine kinase enzyme system. Although PDGF derives its name from the original identification of its source, it is also found in monocytes, macrophages, smooth muscle cells, and endothelial cells. PDGF has numerous actions, including the promotion of angiogenesis, mitogenicity for mesenchymal cells (fibroblasts and smooth muscle cells), stimulation of collagen and matrix formation, and the chemoattraction of neutrophils and macrophages. It is therefore thought to be an important participant in the early response to injury. PDGF accelerates the rate of healing of incisional wounds but may require the presence of other cytokines to perform most effectively. The efficacy of PDGF has already been demonstrated in prospective randomized studies in which it was topically applied to nonhealing cutaneous ulcers.