Growth factors and wound healing: platelet-derived growth factor as a model cytokine.

Cytokines such as the platelet-derived growth factor (PDGF) have the potential to initiate and mediate many if not all of the complex biological responses associated with inflammation and wound healing. PDGF is a potent cytokine that may be used to illustrate the diverse activities initiated by the interactions of PDGF with its receptor relevant to the inflammatory response and subsequent wound repair. Because PDGF can chemotactically attract, activate, and initiate new expression of quiescent genes (e.g. the small inducible gene, SIG, family), it fulfills the predictions anticipated of a candidate wound hormone. PDGF added directly to experimental wounds in animals enhances wound healing, which suggests that cytokines will become increasingly important as therapeutic agents in the treatment of wounds in humans.