血管内皮生长因子基因修饰C17．2神经干细胞移植治疗脑梗死的实验研究

Experimental study on VEGF gene modified C17.2 neural stem cell transplantation for the treatment of cerebral infarction

目的探讨血管内皮生长因子(VEGF)基因修饰神经于细胞(NSC)移植治疗脑梗死大鼠模型的治疗效果,以及基冈的表达情况和神经保护作用。方法通过移植腺病毒载体介导的VEGF165基因转染的C17.2 NSC到大鼠大脑中动脉阻断(MCAO)的局灶性脑缺血模型脑梗死半暗带区,观察移植后大鼠神经功能变化,神经特异性烯醇化酶(NSE)、CD31免疫组化检查观察细胞存活分化和血管新生情况。结果VEGF病毒组、NSC移植组和VEGF基因修饰NSC组神经功能严重度评分均较对照组显著减少(P<0.05),以VEGF基因修饰NSC组最为显著(P<0.05);NSC移植后NSE阳性细胞数较对照组显著增多(P<0.05),VEGF基因修饰NSC组更为显著(P<0.05);VEGF病毒组和VEGF基因修饰NSC移植组脑梗死灶周围血管数较对照组显著增多(P<0.05),以VEGF基因修饰NSC组更为显著(P<0.05)。结论转染VEGF基因的C17.2 NSC脑内移植治疗MCAO脑梗死模型可促进NSC向神经元分化,可促进新生血管形成,改善神经功能。VEGF基因修饰NSC移植治疗效果优于单纯的C17.2 NSC移植或VEGF基因治疗。

Objective To explore the therapeutic effects of vascular endothelial growth factor （VEGF） gene modified C17.2 neural stem cell （NSC） transplantation for the treatment of rat models with cerebral infarction （CI） and to investigate the gene expression state and neuroprotective effect. Methods The rat middle cerebral artery occlusion （MCAO） models established by methods of Longa et al were divided into group A （n=12, control group）, group B （n=14, treatment group with the injection of pAdCMV VEGF 165）, group C （n=18, C 17.2 NSC transplantation group） and group D （n=18, C 17.2 NSC transplantation group with the transfection ofpAdCMV VEGFI65）. The C17.2 NSC, transfected by adenovirus vector-mediated VEGFI65 gene, were transplanted into the CI semi-dark band in the focal cerebral ischemia model of MCAO rats; changes in post-transplantation neural functions were observed and cellular survival and differentiation and the state of vascular regeneration were also observed with NSE and CD31 immunohistochemistry. Results MNSS scores of group B, C and D were significantly lower than of group A （P〈0.05）, especially group D （P〈0.05）; the number of NSE positive cells after NSC transplantation were significantly higher than that of group A （P〈0.05）, especially group D （P〈0.05）; the number of blood vessels around the CI focus of group B and D were significantly higher than that of group A （P〈0.05）, especially group D （P〈0.05）. Conclusion VEGF gene modified CI 7.2 NSC transplantation in treating with MCAO CI models may promote the differentiation of NSC into neurons, enhance regeneration of blood vessels and improve neural functions. The therapeutic effects of VEGF gene modified NSC transplantation are superior to the sole application of C17.2 NSC transplantation or VEGF gene therapy.