Zhang Yong, Cai Zhen-Jie, Chen Ru-Kun
Department of Cardiovascular Surgery, General Hospital of Ji'nan Command, Jinan 250031, China.
Di Yi Jun Yi Da Xue Xue Bao. 2005 Feb;25(2):190-4.
To investigate the possibility of inducing mouse bone marrow stromal stem cells (MSCs) into progenitor cardiomyocytes in vitro.
The MSCs were isolated by adhesion culture in vitro and flow cytometery was employed to identify the phenotypes of the cell passages. 5-azacytidine was used to induce the stem cells to differentiate into cardiomyotes in the experimental group, which were then detected by RT-PCR, semi-quantitative RT-PCR, Western-blot analysis, electron microscopy and immunofluorescence technique.
The isolated subcultured MSCs displayed a fusiform cell-like morphology. The MSCs were uniformly positive for CD29 and CD44 but negative for CD34 and CD45, and after induction, they expressed cardiomyocyte-specific transcription factors (NKx2-5/Csx and GATA4) and fetal ventricular cardiomyocyte-specific gene beta-myosin heavy chain, but not adult ventricular cardiomyocyte-specific gene alpha-myosin heavy chain as detected by RT-PCR. Western blotting identified the expressions of alpha-sarcomeric actin and desmin in the induced MSCs, with myofilament formation observed under electron microscope. Compared with the control group, the expression level of DNA methyltransferase mRNA was significantly lowered in the experimental group as observed by semi-quantitative RT-PCR (P<0.05).
MSCs are capable of differentiating into progenitor cardiomyocytes.
探讨体外诱导小鼠骨髓基质干细胞（MSCs）分化为心肌前体细胞的可能性。
体外贴壁培养法分离MSCs，采用流式细胞术鉴定细胞传代表型。实验组用5-氮杂胞苷诱导干细胞分化为心肌细胞，然后通过逆转录-聚合酶链反应（RT-PCR）、半定量RT-PCR、蛋白质免疫印迹分析、电子显微镜及免疫荧光技术进行检测。
分离培养的MSCs呈梭形细胞样形态。MSCs对CD29和CD44呈均匀阳性，对CD34和CD45呈阴性，诱导后，RT-PCR检测显示它们表达心肌细胞特异性转录因子（NKx2-5/Csx和GATA4）以及胎儿心室肌细胞特异性基因β-肌球蛋白重链，但不表达成人心室肌细胞特异性基因α-肌球蛋白重链。蛋白质免疫印迹法鉴定了诱导后的MSCs中α-肌动蛋白和结蛋白的表达，电子显微镜下观察到肌丝形成。半定量RT-PCR结果显示，与对照组相比，实验组DNA甲基转移酶mRNA表达水平显著降低（P<0.05）。
MSCs能够分化为心肌前体细胞。
