神经干细胞经脑室移植后在损伤脊髓的早期动态分布

目的观察神经干细胞经脑室移植后在损伤脊髓的早期动态分布。方法取转录有绿色荧光蛋白(GFP)基因的孕16 d SD鼠胚脑海马组织,培养成神经干细胞球,注射到脊髓损伤鼠第四脑室,通过免疫染色和电镜,观察其在脊髓的存活、分化状况。结果移植细胞在脊髓表面形成细胞团,大多分布于损伤区头侧的腹、背侧两面。细胞团面积背侧小于腹侧;数目背侧多于腹侧,并于术后5 d达到高峰。这种分布和增殖形式见于损伤脊髓正常部分和无损伤脊髓(对照组)。1周时细胞侵入损伤区,分化并表达神经胶质纤维酸性蛋白(GFAP)。2~3周时与宿主细胞良好融合。结论通过脑脊液移植细胞对于损伤性脊髓进行干细胞移植是一种实用、有效的方法。

Early and dynamic distribution of the stem cells on the injured spinal cord following transplantation through the fourth ventricle

Objective To observe the distribution of hippocampus-derived neural stem cells on the spinal cord surface following injection through the 4th ventricle.Methods Cultured from hippocampal tissues of E16 fetuses with GFP genes,the stem cells were transplanted into cerebrospinal fluid(CSF) in the injured spinal cord through the 4th ventricle.Distribution and differentiation of the stem cells were observed by immunostain and electromicroscopy.Results The transplanted cells formed tiny spots on the pia mater of the spinal cord and proliferated into large cell-clusters.Most of them distributed on the cranial side of the injured area.Usually,the size of the clusters is smaller on the dorsal aspect than on the ventral aspect,the number of clusters is larger on the dorsal side than that on the ventral side.The cell clusters increased rapidly up to 5 days after injection.The number of clusters tended grow larger on the dorsal side than on the ventral side.These patterns of cell dissemination and proliferation were found on intact spinal cord,as well as at the normal part of the contusion-injured spinal cord(control).At the injured site,the cells migrated into the lesion and expressed GFAP immunoreactivity 1 week after injection.2～3 weeks after transplantation,they can migrate and be integrated into the injured spinal cord.Conclusion Transplantation of the neural stem cells through the ventricle into the injured spinal cord is a unique method to disseminate cells all over the spinal cord,and these cells can migrate and be integated into the injured spinal cord.