Human epidermal growth factor/urogastrone: Rapid purification procedure and partial characterization

A new procedure for the isolation of two biologically active forms of human epidermal growth factor (h-EGF-1) and (h-EGF-2) has been devised. Starting with 20 liters of raw human urine, the method employs a six-step fractionation procedure which yields 100–150 μg of h-EGF-1 and 50–100 μg of h-EGF-2. Initial studies suggest that h-EGF-2 may have been derived from h-EGF-1 by removal of the carboxy-terminal arginine or leucine-arginine residue(s). Based on immunological data and electrophoretic mobility at pH 9.5, h-EGF-2 appears to be identical to authentic h-EGF isolated by Cohen and Carpenter (Proc. Natl. Acad. Sci., 1975, 72, 1317). Using the antibody to authentic h-EGF, single precipitin lines of identity are observed between h-EGF-1, h-EGF-2, and authentic h-EGF. Both forms of h-EGF have comparable biological activity in stimulating the growth of adult human skin fibroblasts in culture.