大鼠胚胎神经干细胞纹状体内移植后特性

观察大鼠胚胎神经干细胞移植入成年大鼠纹状体后的存活、迁移和分化状况。自14天胎鼠脑室下区分离获得神经干细胞,利用无血清培养基培养扩增并进行鉴定。经4～5代的扩增后,以BrdU标记的神经干细胞通过脑立体定位注射移植入成年大鼠纹状体内,然后分别于移植后2周、4周、6周和8周时做脑冰冻切片,通过免疫组织化学和免疫荧光方法检测移植细胞的数量、定位和分化情况。8周后移植细胞的检出率约16%;移植细胞向周围宿主组织有广泛的迁移表现,尤以沿着白质束向头尾方向的迁移最为显著,最远向后侧达到内囊;纹状体中移植细胞主要分化为神经元和星形胶质细胞。星形胶质细胞数量最多,主要位于移植区与宿主组织临界部位,而神经元处于移植区中央。培养的大鼠胚胎神经干细胞可以作为移植替代治疗神经退行性疾病研究的供体细胞源,而移植中的迁移现象值得注意。

Characteristics of Embryonic Rat Neural Stem Cells Transplanted to Striatum of Adult Rats

The survival,migration and differentiation of neural stem cells(NSCs) from embryonic rat aftertransplantation to striatum of adult rats were investigated.NSCs isolated from subventricular zone(SVZ) of E14 SDrats,were cultured with serum-free media and identified with nestin staining.After 4-5 passages,NSCs prelabeledby BrdU were transplanted to the striatum of adult rats.Recipient brains were examined at 2,4,6 and 8 weeks aftertransplantation.Immunocytochemistry and immunohistofluorescence techniques were employed to detect the lo-calization and differentiation of the grafts in striatum.About 16% labeled cells were found after 8 weeks and theyexhibited extensive migration from the injection site,especially rostral and caudal along the white matter tracts.Some of them reached the internal capsule.In striatum,the labeled cells differentiated into neurons and glias.Asignificant proportion of the cells developed into glial fibrillary acid protein(GFAP) positive cells which mainlylocated at the border of the graft,whereas neurofilament(NF) positive cells were observed in the core of the grafts.The results suggest that cultured embryonic NSCs can provide a potential source of cell for neuroreplacementtherapy on neurodegenerative disorders such as PD,and cell migration should be considered.