整合素α6对模拟微重力下人牙髓干细胞粘附能力的影响

目的:探究整合素α6对模拟微重力下人牙髓干细胞(human dental pulp stem cells, hDPSCs)粘附能力的影响。方法:以PLGA支架为载体,将采用酶消化法培养的hDPSCs接种在PLGA支架上,分普通重力组和模拟微重力组培养72 h,Western blot检测整合素α6(Integrin α6)、整合素αv(Integrin αv)、整合素β1(Integrin β1)、粘着斑激酶(focal adhesion kinase,FAK)、磷酸化粘着斑激酶(phospho-FAK)的达;si-RNA转染hDPSCs,抑制整合素α6表达,DAPI荧光染色检测转染后hDPSCs在PLGA支架上的粘附数量,Western blot检测转染后hDPSCs中整合素β1、FAK、phospho-FAK的表达。结果:模拟微重力下, 整合素α6、phospho-FAK蛋白水平上调(P＜0.05),整合素αv、整合素β1和FAK的蛋白水平未见显著性差异;si-RNA转染的hDPSCs粘附能力、phospho-FAK蛋白水平均低于对照组(P＜0.05),整合素β1和FAK的蛋白水平未见显著性差异。结论:模拟微重力下,hDPSCs在PLGA支架上粘附能力增强可能与整合素α6及其下游信号分子FAK的表达水平上调相关。

Effects of Integrin α6 on Cell Adhesion in Human Dental Pulp Stem Cells under Simulated Microgravity.

Objective: To study the effects of integrin α6 on cell adhesion of human dental pulp stem cells seeded on PLGA scaffolds under simulated microgravity. Methods: hDPSCs were seeded on PLGA scaffolds and cultured under the conditions of normal gravity or simulated microgravity for 72 hours. The protein expression level of integrin α6, integrin αv, integrin β1, FAK and phospho-FAK were measured by Western blot. Integrin α6 siRNA was transfected into hDPSCs and DAPI immunofluorescence staining was performed to detect the adhesion ability of hDPSCs. Western blot was conducted to detect the related-protein expression levels. Results: Expression of integrin α6 and phospho-FAK were up-regulated in the microgravity group (P＜0.05) compared to control group, while there were no statistical differences in the expression levels of integrin αv, integrin β1 and FAK. Moreover, adhesion ability and phospho-FAK expression of hDPSCs were decreased after transfected with integrin α6 siRNA (P＜0.05), while there were no statistical differences in the expression levels of integrin β1 and FAK. Conclusion: Increased adhesion ability of hDPSCs seeded on PLGA scaffolds may be associated with the up-regulation of integrin α6 and its downstream molecule FAK.