大鼠骨髓间充质干细胞的培养及其向神经元样细胞诱导分化的实验研究

目的：探讨在体外诱导大鼠骨髓间充质干细胞分化为神经元样细胞的方法。方法：分离纯化大鼠骨髓间充质干细胞并用β-巯基乙醇诱导分化为神经元样细胞,使用免疫组化方法鉴定其神经元特异性巢蛋白（nestin）的表达,同时应用脱氧核糖核苷酸末端转移酶介导的缺口末端标记法（TUNEL法）对神经元样细胞的凋亡情况进行定性检测。结果：β-巯基乙醇诱导后MSCs分化为具有典型的神经元形态的细胞,免疫组化实验显示Nestin呈强阳性反应,表明MSCs在体外诱导分化为神经元样细胞。但该细胞在诱导5小时后开始死亡,形态学观察和TUNEL法均确定该死亡为细胞调亡,提示MSCs诱导为神经元样细胞后出现凋亡现象。结论：大鼠MSCs在体外可定向诱导分化为神经元样细胞,其随后发生的细胞死亡属细胞凋亡。

STUDY ON CULTIVATION OF ADULT RAT MESENCHYMAL STEM CELLS AND DIFFERENTIATION INTO NEURON-LIKE CELLS

Objective：To explore a way that induces adult rat bone marrow mesenchyma1 stem cells（MSCs） to differentiate into neuron-like cells in vitro.Methods：MSCs were isolated primarily from adult rat bone marrow by density gradient and then expanded in medium as undifferentiated cells for 3～5 generations.The MSCs were induced into neuron-like cells by β-mercaptoethanol（β-ME）.The expression of neuron-specific marker-Nestin was identified by immunocytochemistry,and the apoptotic phenomenon of neuron-like cells was detected by TUNEL.Results：Most of MSCs were induced to differentiate into neuron-like cells expressing high level of Nestin and assuming the typical appearance of neurons,and the apoptotic process was identified by TUNEL.Conclusion：MSCs could be induced to differentiate into neuron-like cells with high positive rate of induced differentiation in vitro and followed by cell death identified as apoptosis.