Fibronectin enhances healing of excised wounds in rats.

Fibronectin (Fn) is a normal plasma and extracellular matrix glycoprotein that is involved in each phase of wound healing. For example, it is incorporated into both fibrin and collagen fibers; it opsonizes circulating tissue debris for removal by the reticuloendothelial system; it is used by macrophages, fibroblasts, and epithelial cells to move into the wound; and fragments of Fn are chemotactic for fibroblasts. In this study, experiments with rats showed that excised lesions treated with Fn healed more rapidly than paired control lesions treated with the carrier alone. Applications of Fn once a day for two days were as effective in speeding healing as twice-daily applications of Fn for 12 days. A single treatment with Fn soon after the initial injury was nearly as effective as more prolonged treatment regimens.