神经干细胞移植治疗小鼠机械性脑损伤的实验研究

目的探讨神经干细胞移植后的体内存活、增殖与分化,及其对小鼠机械性脑损伤的治疗作用。方法运用牙科钻制作小鼠运动区皮质机械性损伤模型。48只清洁级昆明小鼠,雌雄不拘,体质量为18～20g,按体质量编号随机分为4组:神经干细胞移植组(损伤后原位移植经鉴定确认的原代培养的小鼠神经干细胞)、3T3移植组(损伤后原位移植3T3细胞)、单纯损伤组(损伤后不行神经干细胞移植)和空白对照组(仅施行麻醉),每组12只小鼠。于伤后第3天进行行为学检测;第10、30天行损伤区脑组织nestin及NF200免疫荧光染色,观察神经干细胞生长、分化情况。结果损伤后,获得原代培养的神经干细胞在移植早期贴附于损伤区域且向周边组织呈浸润生长;移植后期Hoechst33342及NF200染色显示损伤区附近可见分化形成的神经元。单纯损伤组小鼠出现偏瘫症状;而神经干细胞移植组小鼠植入神经干细胞后则症状减轻,运动功能明显改善,与其他各组相比差异有显著性意义(P<0.001)。结论神经干细胞移植能够改善小鼠机械性脑损伤后的神经功能状态。

Experimental study on neural stem cell transplantation in mechanical cerebral injury

Objective To study the survival, proliferation and differentiation of neural stem cells (NSC) after transplantation and the therapeutic effect on mechanical cerebral injury (MCI). Methods The MCI model of kunming nude mouse was established by injury of motor cortex with dentist's micro-drill. Forty-eight mice weighed 18-20 g, no matter what sex, were randomly divided into 4 groups according to weight number: ie NSC transplantation group (primarily cultured and identified NSCs were implanted in situ after cortex injury), 3T3 cells transplantation group (3T3 cells were implanted in situ after cortex injury), simple injury group (not performed NSC transplantation after injury) and control group (only performed anaesthesia), 12 mice in each group. Behavior evaluation was carried out in 3 d after injury, expression of Nestin or NF 200 in cerebral tissue of injured area was detected by immunofluorescence staining in 10 d, 30 d after injury. The proliferation and differentiation pattern of NSCs were observed. Results In the early stage after transplantation, the primarily cultured NSCs adhered to injured area and grew into surrounding tissue invasively; In the late stage of transplantation, Hoechst 33342 and NF 200 staining demonstrated the neurons formed from differentiation adjacent to the injured site were found. In simple injury group, hemiplegia occurred after injury, but in NSCs transplantation group their symptoms were attenuated after transplantation of NSCs and the motor function were dramatically improved, which was significantly different when compared with other groups (P < 0.001). Conclusion Transplantation of neural stem cells could improve the neurofunction of mouse after MCI.