Isolation and partial characterization of an endothelial cell growth factor from the bovine kidney: homology with basic fibroblast growth factor.

Two kidney-derived mitogens have been isolated by ion exchange, heparin-Sepharose and reverse-phase high-performance liquid chromatography on the basis of their capacity to stimulate the proliferation of bovine vascular endothelial cells in vitro. Gas phase sequence analysis identified the amino terminal sequences His-Phe-Lys-Asp-Pro-Lys-Arg-Leu-Tyr-X-Lys-Asn-Gly-Gly-Phe-Phe-Leu and His-Phe-Lys-Asp-Pro-Lys-Arg-Leu, respectively. The sequences are identical to residues 16-32 and 16-23 of bovine basic pituitary Fibroblast Growth Factor (FGF). The possibility that these kidney-derived mitogens are related, if not identical, to pituitary basic FGF is supported by the observations that they have similar molecular weights (15-16 kDa), similar retention behavior on all steps of chromatography and similar amino acid compositions, and they share at least some structural homology. Moreover, the kidney-derived growth factors, like basic FGF, are potent stimulators of capillary endothelial cells, granulosa cells, adrenocortical cells and vascular smooth-muscle cells (ED50 = 50 pg). The results demonstrate the existence of a kidney-derived FGF and suggest that at least some of the mitogenic, angiogenic and neovascularising activities described to be present in the kidney are due to the presence of an FGF-like molecule in this tissue.