Effect of compressive stress on proliferation and differentiation of human epidermal stem cells cultured in vitro / 中国病理生理杂志

ABSTRACT

AIM: To investigate the mechanism of proliferation and differentiation of human epidermal stem cells cultured in vitro under the influence of compressive stress.METHODS: Epidermal stem cells were isolated by adhering to type IV collagen and were cultured with conditioned medium,then were detected by Powervision~(TM) two-step immunohistochemical method with keratin 19 and cell cycle analysis.The cultured epidermal stem cells transplanted on silica gel membranes,which were put in a new apparatus,was designed to offer cell culture and intermittent compressive stress(4 kPa,6 kPa,8 kPa,10 kPa,12 kPa) for 2 h,3 times a day simultaneously.A week later,cells on silica gel membranes were identified with keratin 19 and 10 by Powervision~(TM) two-step immunohistochemical method.RESULTS: The new apparatus offered cell culture and intermittent compressive stress simultaneously.The isolated and cultured epidermal stem cells were identified with keratin 19 positive and 84.80 percent of them were showed in G_1 period with cell cycle analysis.Cells on silica gel membranes had been subjected intermittent compressive stress above 8 kPa for a week.The number of the cells was increased,which was more than that in control group.However,some cells identified by immunohistochemical staining with keratin 10 positive were detected among the disposed epidermal stem cells.CONCLUSION: The intermittent compressive stress above 8 kPa induces and promotes epidermal stem cells to proliferate and differentiate,indicating that epidermal stem cells respond to mechanical stress,probably is one of their major biological features.