BDNF-GFP转染神经干细胞修复大鼠脊髓损伤：发挥干细胞与神经因子的双重效应？

摘要 背景：神经干细胞移植入大鼠脊髓损伤模型可以促进功能恢复，基因治疗已被广泛用于治疗脊髓损伤。 目的：确定BDNF-GFP转染后神经干细胞移植对大鼠脊髓损伤的修复效果。 设计，时间和背景：本实验是在中国医科大学基础医学院发育生物学实验室与2009年5月至2010年1月完成。 材料：10只新生Wistar大鼠和88只2-3个月大，雌雄不限的Wistar大鼠。 方法：以携带BDNF-GFP基因的腺病毒转染神经干细胞。88只Wistar大鼠中假手术组8只， 80只大鼠制成T9左侧横断模型，并随机分成四组：BDNF和GFP修饰的神经干细胞移植组，GFP修饰的神经干细胞移植组;单纯神经干细胞移植组和模型组。在各神经干细胞移植组，脊髓损伤后向横断处显微注射等体积细胞，模型组在相同的部位注射等体积的PBS。 主要观察指标： BBB评分检测脊髓损伤模型运动功能恢复情况；制备脊髓损伤模型2周后取材，免疫组化评估BDNF-GFP转染的神经干细胞移植后的细胞学特点；制备脊髓损伤模型2、4、6、8周Real-time PCR检测脊髓横断处BDNF表达情况。 结果： BDNF-GFP转染后神经干细胞在脊髓半切模型中存活并表达BDNF和GFP，移植该细胞后的大鼠体内高表达具有生物活性的BDNF，且脊髓损伤动物运动功能较对照组明显恢复。 结论：移植BDNF-GFP转染后神经干细胞可能是一种修复脊髓损伤的有效的方法。 关键词：神经干细胞，脑源性神经营养因子;绿色荧光蛋白;脊髓损伤;移植。

Repair of spinal cord injury by neural stem cells transfected with brain-derived neurotrophic factor-green fluorescent protein in rats

Abstract Brain-derived neurotrophic factor (BDNF) can significantly promote nerve regeneration and repair. High expression of the BDNF-green fluorescent protein (GFP) gene persists for a long time after transfection into neural stem cells. Nevertheless, little is known about the biological characteristics of BDNF-GFP modified nerve stem cells in vivo and their ability to induce BDNF expression or repair spinal cord injury. In the present study, we transplanted BDNF-GFP transgenic neural stem cells into a hemisection model of rats. Rats with BDNF-GFP stem cells exhibited significantly increased BDNF expression and better locomotor function compared with stem cells alone. Cellular therapy with BDNF-GFP transgenic stem cells can improve outcomes better than stem cells alone and may have therapeutic potential for spinal cord injury. Key Words: neural stem cells; brain-derived neurotrophic factor; transplantation; green fluorescent protein; spinal cord injury; neural regeneration