Wound healing: the role of the macrophage and other immune cells.

The tissue macrophage has been shown to play a critical role in the wound healing process. Through the generation of bioactive substances, macrophages orchestrate the complex processes of cellular proliferation and functional tissue regeneration within wounds. Recent investigations have enumerated many of the specific proteins that are produced by wound macrophages at the site of injury. These include the following: 1) chemoattractants that recruit and activate additional macrophages at the site of injury, 2) growth factors that promote cellular proliferation and protein synthesis, 3) proteases and extra-cellular matrix molecules, and 4) factors that may restrain tissue growth once repair is completed. The development of therapeutic strategies to modulate wound repair continues to utilize key macrophage secretory products.