BASIC FIBROBLAST GROWTH-FACTOR IN THE EARLY HUMAN BURN WOUND

The role of endogenous growth factors in normal wound healing is not c lear. Most of the data on growth factors in healing wounds have been o btained from the application of recombinant exogenous growth factors t o animal and human wounds. We describe the immuno-localization of basi c fibroblast growth factor (bFGF) in the injured dermis of skin from p atients with partial and full-thickness burns. Three antibodies demons trate an extracellular staining pattern of bFGF corresponding to areas of tissue injury that was most intense in specimens collected between 4 and 11 days post-burn injury. In contrast, bFGF staining appeared m arkedly decreased by Postburn Day 17 and was more consistent with unin jured tissue in a 30-day-old burn that had virtually reepithelialized. Basic FGF staining in the nonburned skin from the same patients was r estricted to the dermal capillary basement membranes and the sweat gla nds, which is consistent with other reports of immunoreactive bFGF loc alization in normal adult skin. The immunohistochemical results were c onfirmed with Western immunoblots of the same tissue. The major band a t 16.5 kDa, which is within the recognized range of the bFGF molecule' s several forms, was detected in both burned and unburned tissue from the same patient. These findings support the hypothesis that bFGF is a presynthesized mediator that is stored in either the cells or extrace llular matrix, is released locally from sites of direct injury, and ma y be important in early wound healing. (C) 1994 Academic Press, Inc.