Objective:To study the biologic characters of human foreskin fibroblasts(HFF)to lay the foundation for a long-term culture for human embryonic germ cells in vitro.Methods:The method of separating HFF was investigated.By immunocytochemical method

MTT and flow cytometry

we investigated the morphology and the purity of HFF

study the cell growth curve and cell cycle of HFF

and the effects of different concentrations of mitomycin on growth of HFF at different times.Results:Epidermis and dermis were more easily separated after overnight digestion(12~16 h)in 0.25% Trypsin at 4℃

compared with incubation for 2 h in 5% CO2 at 37℃.Vimentin was strongly positive stained with the purity of 95 percent.There was no obvious stranded period.The rapid proliferation period was in 1~6 d of cell growth curve.The platform stage began at 7 d.Majority of the cells were in G1/G0 phases.The cell cycle corresponded to cell growth curve.Mitomycin C(MMC)inhibited the proliferation of HFF at 12.5 μg/ml over 2.5 h of MMC treatment.Conclusion:Its biological characters showed that HFF can be used as feeder layer for in-vitro cultured human embryonic germ cells。