Notch-1蛋白在诱导骨髓间充质干细胞向肝细胞分化中的表达

目的探讨肝细胞生长因子（hepatocyte growth factor，HGF）、成纤维生长因子-4（fibroblastg rowth factor-4，FGF-4）和间接共培养条件下诱导骨髓间充质干细胞向肝细胞定向分化可行性及Notch信号系统在此分化过程中作用。方法分别采用含有HGF、FGF-4条件诱导液单独培养骨髓间充质干细胞（bone mesenchymM stem cell，BMSC）以及Transwell培养板联合培养MSC和肝细胞，同时加入Notch-1蛋白抑制剂DAPT，通过免疫细胞化学检测白蛋白和Notch-1蛋白表达，RT．PCR检测Notch-1mRNA表达。结果条件诱导液培养第9天免疫细胞化学染色出现白蛋白表达，Notch-1蛋白及Notch-1mRNA表达降低；联合培养组第3天免疫细胞化学染色出现白蛋白表达，Notch-1蛋白及Notch．1mRNA表达降低。加入DAPT抑制Notch信号系统，提高诱导分化率。结论在一定诱导因素作用下，骨髓间充质干细胞可以向肝细胞转化，而且转化的肝细胞具有合成白蛋白功能。在此转化过程中Notch信号系统起到关键作用。

Expression of Notch-1 protein in the differentiation of bone marrow stromal cells into hepatocyte

Objective To investigate the feasibility of differentiation from bone marrow mesenchymal stem cell(BMSC) into hepatocytes and the effect of Notch signaling system in the prosess under HGF, FGF-4 and indirect co-culture condition.Methods BMSCs cultured solituded in conditional induce liquid with component of HGF、FGF-4 and cocuhured with hepatocytes in Transwell culture board,at the same time Notch-1 protein inhibitor DAPT was added.The morphous change of BMSCs was observed by light microscope,the expression of Notch-1 protein was detected by immuocytochemistry and the expression of Notch-1 mRNA was detected by RT-PCR.Results BMSCs cultured solituded swelled obviously on the 9 th day,multi-nucleus cell appeared,and the expression of albumin was observed,the expressions of Notch-1 protein and Notch-1 mRNA decreased;BMSCs cocuhured swelled on the 3 th day,and the expression of albumin was observed by immuocytochemistry,and the rate of differentiation was more than the group cultured solituded,the expressions of Notch-1 protein and Notch-1 mRNA degraded,the expression rate of Notch-1 protein and Notch-1 mRNA was less than the group cultured solituded.Addition of DAPT inhibited Notch signaling system,improved the rate of differentiation.Conclusion In situation of some inducement factors,BMSCs may be differentiated into hepatocyte,and the inverting hepatocyte can synthesize albumin.Notch signaling system plays an important role in the inverting process.