人骨髓间质干细胞治疗实验性变态反应性脑脊髓炎大鼠的实验研究

目的:研究尾静脉注射入骨髓间质干细胞(hMSCs)移植治疗实验性变态反应性脑脊髓炎(EAE)大鼠的疗效及移植后hMSCs在EAE大鼠体内的状况.方法:分离和纯化hMSCs.用豚鼠脑脊髓匀浆免疫Wistar大鼠制备EAE大鼠模型,分别在免疫后10、15、21天经尾静脉注射移植未分化的hMSCs入大鼠体内,通过电镜,动物模型神经功能评分,病理观察hMSCs对EAE大鼠的疗效,利用免疫组化方法观察移植后的hMSCs在EAE大鼠体内存活、迁徙、分化的状况.结果:免疫后10天和15天hMSCs移植组大鼠自移植后10天起其神经功能评分显著低于对照组(P＜0.05);在电镜下治疗组髓鞘超微结构改变明显轻于对照组;病理上各移植组在移植后10、30天脑内脱髓鞘病灶数目明显少于对照组(P＜0.05).hMSCs移植组各时间点大鼠脑组织切片中均可见Brdu、NSE、GFAP、CNPase染色阳性细胞,CNPase( )的少突胶质细胞比例随时间的延长而逐渐增多.结论:hMSCs移植能有效改善EAE动物的神经功能评分,减少脱髓鞘病灶数目,并且在体内微环境改变信号的影响下分化成神经元、星型胶质细胞、少突胶质细胞.

Experimental study of human mesenchymal stem cells transplantation in treating experi-mental autoimmune encephalomyelitis of rats

Objective:To explore the effect of the human mesenchymal stem cells(hMSCs) transplantation on treating experimental autoimmune encephalomyelitis(EAE) rats and the status of transplanted hMSCs in the brain tissue of EAE rats. Methods:hMSCs were isolated from human adult bone marrow. EAE rat models were made, and the human mesenchymal stem cells were transplanted into the rat tail vein 10,15 and 21 days after immunization. The neurological signs were undertaken in all the groups every day after immunization. Rats were sacrificed at different time. The differentiation and migration of the human mesenchymal stem cells in vivo,and the number and status of the demyelinated foci were checked by electronic microscope and immunohistology. Results:Rats that received transplantation had a significant improvement compared with the control group in the observation of electronic microscope. Twenty days later, rats that received transplantation 10 and 15 days after immunization had a significant improvement of clinical outcome compared with the control group(P < 0.05). The number of demyelinated foci decreased significantly(P < 0.05). The human mesenchymal stem cells were induced to differentiate into astrocytes, oligodendrocytes and neurons in vivo. Immunohistological result confirmed that the transplanted stem cells migrated to the demyelinated foci. Conclusion:The human mesenchymal stem cells differentiated into three main types of neural cells by the influcence of the EAE microenvironment signals.Human mesenchymal stem cells transplantation could effectively improve the neurologic function of rats, and decrease demyelinated foci number.