What roles do platelet derived growth factor and transforming growth factor beta play in wound healing?
Platelet-derived growth factor (PDGF) is released initially by platelets in the inflammatory phase during the formation of the initial thrombus. It is an important chemoattractant and activator of macrophages, which arrive to orchestrate wound healing. These macrophages then secrete additional growth factors that include more PDGF. These growth factors attract, recruit, and activate additional macrophages.
Transforming growth factor beta (TGF-β) is released by macrophages and platelets. It is a potent chemoattractant and activator of fibroblasts, stimulating them to form collagen. TGF-β is the major growth factor involved in collagen synthesis.