中文摘要：

目的探讨重编程脂肪干细胞（ADSCs）移植治疗大鼠脊髓损伤（SCI）的作用和修复机制。方法体外培养、纯化和鉴定大鼠ADSCs,并利用慢病毒包装神经元生成素2（Ngn2）基因转染大鼠第3代ADSCs。建立大鼠SCI模型后,48只雌性SD大鼠随机均分为A（SCI对照）、B（单纯ADSCs移植）和C（Ngn2-ADSCs移植）三组。采用BBB评分评价大鼠运动功能,HE染色、免疫组化和免疫荧光的方法检测脊髓组织学情况和相关蛋白的表达水平。结果重编程ADSCs在神经分化诱导后,神经元标记物（NeuN）阳性表达率达到90%以上。免疫荧光结果显示,细胞移植后4周,在脊髓损伤中心区域可见大量移植的ADSCs细胞表达GFP阳性。C组的BBB评分高于其他组,并且HE染色显示脊髓空洞面积小于其他两组（P〈0.05）,同时BDNF和VEGF蛋白含量也高于其他两组（P〈0.05）。结论重编程ADSCs移植后能有效地存活并分化为神经细胞,减小脊髓损伤空洞,增加BDNF和VEGF表达,促进SCI大鼠的运动功能恢复,较单纯应用ADSCs能更好地促进SCI修复。

英文摘要：

Objective To investigate the therapeutic effects of reprogrammed adipose-derived stem cells（ADSCs）in a rat model with spinal cord injury（SCI）.Methods ADSCs from rats were cultured in vitro,which were purified,identified,and genetically modified with the neurogenin 2（Ngn2）gene.Forty-eight adult female SD rats were randomly and equally assigned to three groups of A（as model control）,B（transplanted with ADSCs）and C（transplanted with Ngn2-ADSCs）.The hindlimb motor function of rats was recorded using the Basso,Beattie and Bresnahan（BBB）locomotor rating scale.The histologic examination of the spinal cord was performed by HE staining and immunohistochemistry 4 weeks after transplantation.Results After neural induction,the positive expression rate of NeuN in group C was more than 90%.A great number of ADSCs-GFP was found in the center of injured spinal cord in the 4th week after cell transplantation.Compared to groups of A and B,the expressions of brain-derived neurotrophic factor（BDNF）and vascular endothelial growth factor（VEGF）were significantly increased（P〈0.05）,the BBB score was higher and the cystic cavity area was smaller in group C（P〈0.05）.Conclusion The transplanted reprogrammed ADSCs can be survival and differentiate into neuron cells,which may increase the expressions of BDNF and VEGF,promote the regeneration of the injured neuron,and improve the recovery of motor function in a more efficient way than that with ADSCs alone in SCI rats.