Histatin as a synergistic stimulator with epidermal growth factor of rabbit chondrocyte proliferation

Histatin 5 dose-dependently increased DNA synthesis in rabbit costal chondrocytes in culture. The level of DNA synthesis was stimulated by histatin 5 to about 4 times that of the control. The combination of histatin 5 and epidermal growth factor (EGF) increased the DNA synthesis to about 40 times that of the control while EGF alone stimulated it 15-fold, indicating synergistic stimulation by both factors. Enzyme-linked immunosorbent assay using anti-histatin 5 demonstrated that human serum contained histatin-like substances. These findings suggest that histatins play an important role in chondrocyte proliferation, presumably as a physiological modulator of the action of EGF.