转人CD59基因小鼠对人补体介导的免疫反应的保护作用

Transgenic mice expressing recombinant human CD59 gene against human complement-mediated attack

目的:探讨转基因小鼠血管内皮细胞特异性表达人CD59(hCD59)基因对人补体介导的免疫反应的保护作用。方法:通过显微注射方法建立转hCD59基因小鼠,采用PCR、Southernblot方法检测hCD59基因的整合,流式细胞仪检测hCD59蛋白的表达,人血清体外灌注转基因小鼠心脏、免疫组织化学染色补体C9及IgG评估排斥反应的情况。结果:转基因小鼠hCD59基因表达强度为人外周血白细胞的35%～120%,转基因小鼠体外灌注心脏存活时间明显延长(P<0.01),心脏补体C9沉积明显减少。结论:血管内皮细胞特异性表达hCD59可以减轻异种移植排斥反应,延长移植物的存活时间。

Aim: To explore the role of expression of recombinant human CD59 (hCD59) gene in transgenic mice endothelial cells against human complement-mediated attack. Methods: Transgenic mice expressing hCD59 were generated by microinjection of a recombinant hCD59 gene under the control the human ICAM-2 promoter. The offspring were tested for transgene integration by using PCR and Southern blot, and for hCD59 expression on peripheral blood leukocytes (PBLs) by flow cytometry. Hearts from transgenic mices were perfused in vitro with human plasma. Immune rejection was evaluated by immunohistochemical analysis of hearts for C9 and IgG. Results: Expression levels of hCD59 ranged from 35% to 120% of that on human PBLs. Hearts perfused with human plasma showed longer survival time, and deposition of human C9 was greatly reduced in transgenic hearts. Conclusion: High-level vascular endothelial-specific expression of hCD59 could overcome hypercute rejection of xenotransplantation,and prolong xenograft survival.