目的 探讨异种神经干细胞注射到玻璃体腔后迁移到视网膜的存活及分化。方法 将起源于人胚胎大脑脑室下区的神经干细胞悬浮液注射到SD大鼠的玻璃体腔中。分别于手术后4周和6周处死并剥离出视网膜,进行免疫组织化学染色,在荧光显微镜下观察实验结果。结果 术后4周和6周均可见有移植细胞存活,术后6周时移植前微管相关蛋白2(MAP2)阴性表达的移植细胞,移植后为阳性表达。结论 起源于人胚胎大脑脑室下区的神经干细胞可以迁移到视网膜组织中存活,并且可以进一步分化。
Objective Previous studies has shown that rat neural stem cells can be successfully transplanted into rat retinas and differentiate into neurons and gila, In the present study, the survival and differentiation of heterogeneity neural stem cells,called human hypo-encephalocoele-derived neural stem cells,in retina after injected into vitreous space was determined, Methods Twelve adult SD rats were assigned to three groups randomly. Mechanical injury was induced in the optic nerve of SD rats by clamping the optic tract for 5 minutes. The nucleus of human hippocampus-derived neural stem cells were labeled with Hoechst 33342. Stem cells suspension was slowly injected into the vitreous space in the rats of surgery 4-week group(4 eyes) and 6-week group(4 eyes), and the solvent without heterogeneity neural stem cells was injected in the rats of surgery control group(4 eyes). The fellow eyes of rats was as normal control group. The specimens were processed for immunohistochemical studies. Results Many positive labeled stem cells by Hoechst were seen in retina of rats in surgery 4-week group and 6-week group, showing a mount of scattering blue points under the fluorescing microscope, and no positive labeled cell nucleus were seen in surgery control group and normal control group. The cytoplasma of grafted cells showed hadro-immunoreactivity ( red color) for microtubule associated protein 2, suggesting grafted cells differentiated into cells of neuronal lineages in the retina of rats of surgery 6-week group, and no similar reaction was found in surgery 4-week group. Conclusion The incorporation and subsequent differentiation of the grafted stem cells into neuronal and glial lineage can be achieved by injecting the human hypoencephalocoele-derived neural stem cells into vitreous space.