诱导大鼠间充质干细胞形成的神经元样细胞的形态特征

MORPHOLOGIC CHARACTERISTICS OF NEURON-LIKE CELLS INDUCED FROM THE RAT BONE MARROW MESENCHYMAL STEM CELLS

目的 研究诱导大鼠骨髓间充质干细胞（MSCs）形成的神经元样细胞的形态特征。方法 通过贴壁法培养鉴定大鼠骨髓MSCs，体外培养扩增纯化后加入新生鼠脑匀浆上清诱导48h。倒置显微镜和透射电镜下观察诱导前后细胞的形态结构变化，免疫细胞化学方法鉴定诱导后细胞的性质。结果 倒置显微镜下可见MSCs呈纺锤形和多角形，核居中，有1或2个核仁，诱导后细胞呈神经元样，细胞伸出较长的轴突样和树突样突起；免疫组织化学方法显示NSE、NF阳性，GFAP阴性。透射电镜下可见诱导前MSCs胞质较丰富，有较多的细胞器，细胞核呈圆形或椭圆形，也可见不规则形核，核染色质较疏松，有明显核仁，多为1个。有的MSCs表面可见较多的微绒毛。诱导后细胞胞质丰富，细胞核多为不规则形，染色质疏松，核仁较大，1～3个不等，细胞表面有发达的微绒毛。结论 MSCs是一种多分化潜能的细胞，诱导后分化成为具有成熟细胞器的神经元。

Objective To investigate the morphologic characteristics of neuron-like cells induced from the rat mesenchymal stem cells（MSCs）. Methods The rat MSCs from bone marrow were cultured by being adhered to the culture dish. The thirdgeneration of the MSCs were induced by the neonate rat brain homogenate supernatant for 48 hours. The morphological characteristics and the ultrastructures of both non-induced and induced MSCs were observed under the inverted microscope and the electron microscope. The property of the induced cells was identified by using immunocytochemical method. Results Under the inverted microscope MSCs showed spindle or polygon-shaped cell bodies and the nuclei with one or two nucleoli were located in the middle of the cells. After the inducement the cells appeared neuron-like with axonlike and dendrite-like processes. The neuron-like cells were neuron special endolase（NSE）, neurofilament protein（NF） positive and gllal filbrillary acidic protein（GFAP） negative by irnmunocytochemical staining. Under the electron microscope the MSCs had plentiful cytoplasm and organelles and had an obvious nuclei containing a nucleoli. There were a lot of microvilli on the surfaces of the MSCs. The neuron-like cells had plentiful cytoplasm and irregular nuclei with one to three nucleoli. There were also plenty of microvilli on the cell surfaces. Conclusion MSCs are one kind of multipotent stem cells and can differentiate neurons with matured organelles induced by the neonate rat brain homogenate supernatant.