pSVPoMcat微基因修饰雪旺细胞移植对脊髓损伤的修复作用

EFFECT OF INTASPINAL IMPLANTATION OF MICROGENE pSVPoMcat GENETICALLY MODIFIED SCHWANN CELLS ON SPINAL CORD INJURY REPAIR IN RATS

为观察pSVPoMcat微基因修饰雪旺细胞 (SC)移植对脊髓损伤的修复作用 ,采用切割法制备脊髓半横断损伤模型 (T8平面 )。实验动物随机植入 pSVPoMcat微基因修饰的SC(A组 )、SC组 (B组 )和损伤对照组 (C组 ) ,每组 40只。术后应用联合行为记分(CBS)和皮层体感诱发电位 (CSEP)动态观察大鼠功能恢复情况 ,应用原位杂交和免疫细胞化学方法观察胶质纤维酸性蛋白 (GFAP)的表达。术后 3月行MRI观察 ,并用免疫组化对神经轴突进行神经中丝 (NF)染色。结果显示 ,A组能抑制大鼠损伤后的GFAP表达 ;MRI发现 ,A组大鼠脊髓损伤 (SCI)区脊髓信号已基本恢复正常 ,B组未恢复正常 ,而C组SCI有软化灶形成。与NF染色发现一致。A、B两组潜伏时波幅呈恢复的趋势 ,与A组接近正常 ,与CBS结果一致。提示 ,pSVPoMcat微基因修饰SC移植能抑制SCI后GFAP的表达 。

To observe the effect of intaspinal implantation of Schwann cells (SC) genetically modified with microgene pSVPoMcat on spinal cord injury (SCI) repair.120 SD rats were used to establish the hemisected spinal cord injury model at T 8 level,and they were divided randomly into three groups: genetically modified SC implantation group (group A),normal SC implantation group (group B) and control group without cell implantation (group C).One week after the operation ,combined behavioral score(CBS) and the cortical somatasensory evoked potential (GFAP) were measured and the expression of glial fibrillary acidic protein(GFAP) was examined by in situ hybridization and immunocytochemistry.Three months after the operation, all the rats were scanned with MRI and then were sacrificed.Neurofilament (NF) was examined with imunohistocytochemistry staining by using NF monoclonal antibody. Following were the results:(1) In group A,the number of cells expressed GFAP in injured sites was less than that in groups B and C.(2) MRI scanning showed that the SCI region almost recovered in group A but did not recover in group B.There was a malacie focus in SCI region in group C.This was corroborated by the NF staining.(3) The amplitudes of potential in the latent period in group A and B showed a tendency to recover,and it was consistent with CBS.The results suggested that the implantation of genetically modified SC with microgene pSVPoMcat could inhibit GFAP expression and promote the functional recovery of spinal cord injury in rats.