Epidermal Growth Factor (EGF) has an effect on the differentiation of specific cells in vivo and is a potent mitogenic factor for a variety of cultured cells of both ectodermal and mesodermal origin. EGF stimulates the growth of various epidermal and epithelial tissues in vivo and in vitro and of some fibroblasts in cell culture. Recombinant Mouse Epidermal Growth Factor produced in E. coli is a single non-glycosylated polypeptide chain containing 53 amino acids including 3 intramolecular disulfide-bonds with a MW of 6 kDa.