ABSTRACT
The aim of this study is to investigate the mitogenic effect of basic fibroblast growth factor [FGF], insulin-like growth factor-I [IGF-I] and epidermal growth factor [EGF], comparing their effects with media alone [MEM] in a human skin explant model. A stable organ culture system for maintaining the histologic structure of human epidermis for 10 days in vitro was developed. DNA synthesis was measured on days 1, 3 and 7 of organ culture using 3H-thymidine [3H-thy] uptake and expressed as cpm/mg dry weight [mean +/- SEM]. FGF, IGF-1 and EGF were each capable of stimulating 3H-thy uptake on day 1 of culture. IGF-1 and EGF also stimulated 3H-thy uptake on days 3 and 7 of culture. The organ culture system was further employed to observe epidermal outgrowth. Longest keratinocyte outgrowth from the explant periphery [simulating epithelial regeneration from the wound edge] was observed on day 7. EGF resulted in maximum stimulation of epithelial outgrowth [440 +/- 80 mum], followed by FGF, IGF-1 and MEM