骨髓间充质干细胞体外增殖及分化过程中Notch信号的表达变化

Notch signaling system regulates the proliferation and differentiation of mesenchymal stem cells in vitro

目的研究Notch信号系统对骨髓间充质干细胞的增殖与分化的调控作用。方法用密度梯度离心法分离培养犬骨髓间充质干细胞,观察其增殖及传代情况,并进行成骨、成软骨及成心肌细胞诱导,Western blot检测细胞增殖及分化过程中Notch信号蛋白的表达。结果骨髓间充质干细胞呈梭形、旋涡样生长,增殖及传代能力强,可在体外形成钙结节,分化为软骨细胞,免疫组化示心肌细胞标志物的表达。Western blot显示在增殖过程中可见Notch信号蛋白的表达,为1.00±0.13,当分化为骨细胞及心肌细胞时,其表达上调,分别为1.20±0.14及1.70±0.17,与增殖的干细胞相比有明显差异(P<0.05)。结论 Notch信号系统对骨髓间充质干细胞的增殖及分化起重要的调控作用。

Objective To investigate the regulation of the proliferation and differentiation of mesenchymal stem cells（MSCs） by Notch signaling system.Methods MSCs were isolated from canine bone marrow and cultured,then osteogenesis,cartilage and cardiomyocytes differentiation were induced.The identification of Notch signal was carried out.MTT method was used to make a the growth curve.Results MSCs looked like fusiform under light microscope.MSCs differentiated into calcium nodules and chondrocyte.Immunohistochemistry showed a significantly increased expression of TnT.Western blotting showed that the protein of Notch signal expressed during proliferation and the level of expression was significantly higher during differentiation（P0.05）.Conclusions Notch signaling system plays an important role in the proliferation and differentiation of mesenchymal stem cells.