【摘要】 背景:人尿源性干细胞是近年来新发现的成体干细胞,其来源不受限制,提取简便,具备良好的增殖能力及多向分化潜能,近年来已应用于泌尿系疾病中的神经功能修复,如应激性尿失禁以及膀胱输尿管返流等。目的:探索人尿源性干细胞向神经元样细胞诱导分化能力及对大鼠脊髓损伤的修复作用。方法:体外获取人尿源性干细胞后利用流式细胞仪检测其细胞表型,将人尿源性干细胞向神经元样细胞诱导后进行免疫组织化学染色鉴定。采用Allen方法制作大鼠T9节段脊髓损伤模型,24只SD大鼠被随机分为2组:脊髓损伤组和人尿源性干细胞组,每组12只。人尿源性干细胞组在脊髓损伤后第1天于损伤脊髓边缘注入2μL细胞浓度为1.0×1011 L-1人尿源性干细胞,脊髓损伤组注入等量含体积分数为10%胎牛血清的L-DMEM培养液,于造模后第1,10,20,30天进行BBB评分,第30天取各组损伤脊髓组织分别进行Luxol Fast Blue染色、小胶质细胞/巨噬细胞染色和胶质纤维酸性蛋白染色,并计算损伤脊髓面积和胶质纤维酸性蛋白荧光强度。结果与结论:①人尿源性干细胞高表达CD29、CD90,而低表达CD45,并且在体外可向神经元样细胞诱导分化;②造模后第1,10天两组大鼠BBB评分差异无显著性意义(P>0.05),第20,30天人尿源性干细胞组BBB评分明显高于脊髓损伤组(P<0.05);③人尿源性干细胞组脊髓损伤面积明显低于脊髓损伤组(P<0.05),胶质纤维酸性蛋白染色显示人尿源性干细胞组荧光强度明显低于脊髓损伤组(P <0.05);④结果表明,人尿源性干细胞能向神经元样细胞分化,并对大鼠脊髓损伤具有修复作用。更多还原

【Abstract】 BACKGROUND: Human urine-derived stem cells are newly discovered adult stem cells, characterized by rich sources, simple extraction, good proliferative ability and multi-directional differentiation potential. In recent years, human urine-derived stem cells have been used for the repair of neurological functions in urinary diseases, such as stress urinary incontinence and vesicoureteral reflux. OBJECTIVE: To explore the biological characteristics of human urine-derived stem cells and to study their repairing effect in a rat model of spinal cord injury. METHODS: Cell phenotypes of human urine-derived stem cells were detected using flow cytometry, and the immunohistochemical staining was used to identify neuron-like cells differentiated from human urine-derived mesenchymal stem cells. Then, an animal model of spinal cord injury at T9 segment was made by Allen method, and after modeling 24 Sprague-Dawley rats were assigned into spinal cord injury group or cell treatment group(n=12/group). In the cell treatment group, the model rats were injected 2 μL of 1.0×1011/L human urine-derived stem cells, while in the spinal cord injury group, the rats were administered the same volume of L-DMEM containing 10% fetal bovine serum. Basso, Beattie and Bresnahan scores were valued at 1, 10, 20, and 30 days after modeling. Spinal cord samples from all the rats were taken out at 30 days after modeling, and Luxol Fast Blue staining, microglia/macrophages staining and glial fibrillary acidic protein staining were used to value the injured area of the spinal cord and the fluorescence intensity of glial fibrillary acidic protein. RESULTS AND CONCLUSION:(1) Flow cytometry showed high expression on CD29 and CD90, and low expression on CD45 in human urine-derived mesenchymal stem cells. Moreover, human urine-derived mesenchymal stem cells could be induced to differentiating into neuron-like cells in vitro.(2) Basso, Beattie and Bresnahan scores showed no significant difference between the two groups at 1 and 10 days after modeling(P > 0.05), while, at 20 and 30 days after modeling, the scores in the cell treatment group were significantly higher than those in the spinal cord injury group(P < 0.05).(3) Luxol Fast Blue staining showed that the injured area of the spinal cord in the cell treatment group was markedly less than that in the spinal cord injury group(P < 0.05), and the glial fibrillary acidic protein showed lower fluorescence intensity in the cell treatment group than the spinal cord injury group(P < 0.05). To conclude, human urine-derived stem cells can differentiate into neuron-like cells and have therapeutic effects in the rat model of spinal cord injury.更多还原