SPLEEN-DERIVED GROWTH-FACTOR, SDGF-3, IS IDENTIFIED AS KERATINOCYTE GROWTH-FACTOR (KGF)

A heparin-binding mitogen rat for rat hepatocytes was partially purifi ed from bovine spleen by a combination of heparin-affinity, cation-exc hange and gel-filtration chromatography. Besides stimulating rat hepat ocytes, this factor, which was designated spleen-derived growth factor -3 (SDGF-3), exhibited mitogenic activity for mouse epidermal keratino cytes but not mouse fibroblasts. Its apparent epithelial specificity a nd heparin-binding properties corresponded to those of keratinocyte gr owth factor (KGF). These findings, together with the fact that the mit ogenic activity of SDGF-3 was abolished by a neutralizing monoclonal a ntibody specific for KGF, identify this bovine spleen-derived hepatocy te mitogen as KGF.