脐带间充质干细胞移植治疗大鼠重症肌无力的研究

Umbilical Cord Mesenchymal Stem Cell Transplantation for Treatment of Experimental Autoimmune Myasthenia Gravis in Rats

脐带间充质干细胞因其来源广泛,易扩增,低免疫原性等特点被人们越来越多地应用于疾病治疗的研究中。本研究旨在为重症肌无力疾病探求一种新的应用干细胞的治疗方法。将脐带间充质干细胞(UCMSC)移植到重症肌无力大鼠中,应用免疫荧光法观察人源化细胞的分布,ELISPOT法观察MSC对B细胞原位分泌抗体的影响,Transwell试验检测分泌IFN-γ的水平。结果发现,经静脉输注的UCMSC能快速的迁移到炎症部位和局部淋巴结,而且在淋巴结的髓质区也可以检测到人源化的细胞。体外原位检测乙酰胆碱受体(AchR)抗体分泌的试验发现,当MSC与淋巴结来源的淋巴细胞充分接触,能有效地抑制AchR抗体的产生。Transwell试验显示,UCMSC与CD4T细胞直接接触,能有效地降低IFN-γ的产生,在一定程度上缓解重症肌无力体内的Th1/Th2细胞失衡的免疫状态。结论 :在重症肌无力大鼠中,MSC可能通过相互接触或/和释放细胞因子而调节机体的免疫反应,这为重症肌无力提供了一种潜在的治疗新途径。

Umbilical cord mesenchymal stem cell （UCMSC） transplantation has been widely used in the treatment of a variety of diseases due to their advantages such as abundant resources, low immunogenicity and large ex vivo expansion capacity. This study was aimed to investigate the effects of UCMSC on experimental autoimmune myasthenia gravis （EAMG） rats. The distribution of human-derived cells was observed by immunofluorescence method, the effect of MSC on B-cell in situ-secreted antibodies was assayed by ELISPOT, the secreted IFN-γ level was detected by using Transwell test. The results showed that UCMSC were able to migrate to inflammation region and lymph nudes, moreover humanderived cells could be detected in medulla zone of lymph nudes. In vitro in situ detection of AchR specific antibody secretion revealed that the full contact of MSC with lymphnude-derived lymphocytes could effectively inhibit production of AchR antibody. Transwell test indicated that the direct contact of UCMSC with CD4 T cells could effectively decrease production of IFN-γ, which modulated the unbalance between Th1/Th2 to a certain extent. It is concluded that UCMSC can regulate the immune system by direct cell-cell contact or/and release of cytokines, which bring a new insight into knowlege about MSC-based therapy for EAMG.