中文摘要：

目的：探讨神经营养素-3（NT-3）基因修饰雪旺细胞（SCs）和神经营养素-3受体（TrkC）基因修饰骨髓间充质干细胞（MSCs）联合移植对全横断脊髓损伤（SCI）大鼠的大脑皮质感觉运动区、红核和背核受损伤神经元存活的影响，为细胞治疗和基因治疗的临床应用提供依据。方法：将含有NT-3-SCs和TrkC—MSCs的PLGA高分子支架移植到大鼠脊髓全横断损伤处。在术后第67天，取其大脑和脊髓进行冷冻切片。用免疫荧光组织化学染色方法，检测SCI处SCs和MSCs的存活及其外源性基凶的表达，并计算大脑皮质感觉运动区内锥体细胞层、中脑红核和L1脊髓背核的神经元数量。结果：2个月后，可见SCI处有移植的SCs和MSCs，其中转染的外源性基因NT-3和TrkC可在移植细胞内表达。NT-3-SCs＋TrkC-MSCs移植组大脑皮质感觉运动区内锥体细胞层、中脑红核和L1脊髓背核的神经元数量明品高于其他组。结论：NT-3基因修饰SCs和Trkc基因修饰MSCs联合移植能够促进全横断SCI大鼠的大脑皮质感觉运动区、中脑红核和脊髓背核受损伤神经元的存活。

英文摘要：

Objective：To explore the effects of co-transplantation of neurotrophin-3 （NT-3） gene modified Schwann cells （SCs） and NT-3 receptor （TrkC） gene modified bone marrow mesenchymal stem cells （MSCs） on the neuronal survival in internal pyramidal layer of sensorimotor cortex, red nuclei and Clarke＇s nuclei after rats＇ spinal cord transection, and to provide the instruction for clinical application of cell and gene therapy. Method： The high polymer PLGA scaffolds containing NT-3-SCs and TrkC-MSCs were immediately transplanted into the transected sites of rats＇ spinal cord. At the 67th d after operation, brains and spinal cords of rats were removed and sectioned frozenly. The survivals of SCs and MSCs and the expressions of NT-3 and TrkC genes in the injured sites of spinal cord were examined by immunofluoreseence histochemistry, and the amounts of neurons in internal pyramidal layer of sensorimotor cortex, red nuclei of brain stem and Clarke＇s nuclei of L1 spinal segment were calculated. Result： The transplanted SCs and MSCs could survive, and NT-3 and TrkC could express in transplanted ceils after 2 monthes. The amounts of survival neurons in internal pyramidal layer of sensorimotor cortex, red nuclei of midbrain and Clarke＇s nuclei of L1 spinal segment in NT-3-SCs＋TrkC-MSCs group were move than those in other groups. Conclusion： Co-transplantation of NT-3 genes modified SCs and TrkC genes modified MSCs may promote the survival of neurons of cerebral coxtex, red nuclei and Clarke＇s nuclei after rat soinal cord transection.