ABSTRACT
Macrophages are key immune cells derived from monocyte precursors that have a vital role not only in innate and adaptive immunity but also tissue healing and remodeling as well. Normal healing is a complex sequence of events coordinating hemostasis, inammation, and ultimately organized tissue regeneration (Martin 1997). Following injury, platelet aggregation initiates the clotting cascade, followed by inltration of the wound bed with pro-inammatory, cytokine-producing leukocytes, including neutrophils and macrophages. In later stages of healing, broblasts are recruited to the wound, depositing extracellular matrix (ECM) proteins such as collagen, bronectin, and hyaluronic acid, leading to new tissue regeneration (Witte and Barbul 1997, Darby and Hewitson 2007). When considering tissue healing, the body has three primary objectives: to stop bleeding, to prevent infection, and to restore tissue function. These goals are illustrated, or addressed, in the characteristic phases of wound healing, including inammation, proliferation, and remodeling. Even under optimal conditions, prudent wound care very often leads to contracture, loss of domain, and brosis or scarring. Therefore, there are many aspects of the healing process that may affect decision making, the use of an implant or biomaterial construct, and, ultimately, clinical outcome.
