尿嘧啶脱氧核苷及超顺磁性氧化铁双标记的神经干细胞活体移植后细胞迁徙及功能性分化的实验研究

目的观察尿嘧啶脱氧核苷(Brdu)及超顺磁性氧化铁(SPIO)双标记的神经干细胞活体移植后存活细胞的迁徙及分化。方法SPIO和Brdu对神经干细胞进行双标记,移植至大脑中动脉梗死模型的对侧脑组织,术后采用MRI监测。第6周MRI检查后取组织切片行免疫组织化学染色,观察神经干细胞的迁徙及分化。结果双标神经干细胞活体移植后第3周MRI开始显示细胞沿胼胝体迁徙,第6周脑组织免疫组织化学染色亦显示干细胞沿胼胝体向对侧迁徙,免疫组织化学荧光双标染色显示移植的神经干细胞可以分化为星形胶质细胞及神经元。结论移植存活的神经干细胞在迁徙过程中能够进行功能性分化。

Cell differentiation and migration of transplanted neural stem cells bi-labeled with Brdu and superparamagnetic iron oxide in ischemic model

Objective To study the migration and functional differentiation of transplanted neural stem cells bi-labeled with Brdu and superparamagnetic iron oxide (SPIO) with MR imaging and immunohistochemistry method in ischemic rats.Methods Rat neural stem cells (NSCs) co-labeled with SPIO mediated by poly-L-lysine and bromodeoxyuridine (BrdU) were transplanted into the middle cerebral artery occlusion (MCAO) rats after 14 days when MCAO model was made successfully.4.7T MR scanner was used to monitor the migration of transplanted cells post-transplantation.After MRI in the 6th week,the rats were killed and underwent immunohistochemistric staining to study migration and functional differentiation of NSCs.Results Three weeks after transplantation,linear hypointensity area derived from migration of labeled NSCs was observed in the corpus callosum adjacent to the injection site.Six weeks after transplantation,immunohistochemical examination showed the migration of NSCS along the corpus callosum toward the ischemic zone.Co-labeled immunohistochemical methods demonstrated transplanted NSCs could differentiate into astrocytes and neurons.Conclusion Transplanted NSCs into ischemic rat can differentiate into astrocytes and neurons during the process of migration.