人-NOD/SCID小鼠异种急性移植物抗宿主病模型的建立

目的 建立一种人-NOD/SCID小鼠嵌合的异种急性移植物抗宿主病(aGVHD)模型.方法 NOD/SCID小鼠给予亚致死剂量的60Coγ射线全身照射后经尾静脉输注动员后人外周血单个核细胞(PBMNC),移植后每周检测血常规,采用流式细胞术检测人CD45+细胞的比例,分析人淋巴细胞亚群,取各脏器组织检测人、鼠保守基因序列片段,并进行免疫病理分析.结果 移植后1周起NOD/SCID小鼠的血细胞中有明确的人CD45抗原表达,随人CD45+细胞比例增高逐渐出现以体重减轻和血细胞减少为主要表现的异种急性移植物抗宿主病(X-GVHD),人-NOD/SCID嵌合体的基因组DNA中可扩增出入β-globin及小鼠保守基因HYPSIN序列片段,移植后6周生存率约为14%;人-NOD/SCID嵌合体中以人T淋巴细胞的植人为主,CD4+/CD8+细胞比例倒置;X-GVHD以人的淋巴细胞浸润为主,肝脏与肺脏是主要靶器官.结论 NOD/SCID小鼠预先给予亚致死剂量照射,再经尾静脉输注入PBMNC,能够建立X-GVHD模型.临床表现主要为植入率相关的体重减轻和血细胞减少,病理表现靶器官主要为肝脏和肺脏.该模型建立方法简便,X-GVHD发生时间(2～3周)较早,发生率(94%)高,便于在此基础上进行aGVHD防治的动物实验研究.

Establishment of an xenogeneic acute graft-versus-host disease model in NOD/SCID mice by engraftment of G-CSF mobilized human mononuclear cells

OBJECTIVE: To establish an xenogeneic acute graft-versus-host disease model by engraftment of G-CSF mobilized human mononuclear cells into NOD/SCID mice. METHODS: Mobilized human peripheral blood mononuclear cells (PBMNCs) were transplanted into sublethally irradiated NOD/SCID mice. After transplantation, complete blood count, huCD45+ cells and other phenotype human lymphocytes were determined weekly. Mice were sacrificed, and their tissues were examined histopathologically and immunophenotypically. Genomic DNA was also prepared for detecting human beta-globin DNA sequence and endogenous mouse RAPSYN gene. RESULTS: The human CD45+ cells in the mice appeared 1 week after transplantation. Its percentage was increased with an acute X-GVHD syndrome characterized by rapid and severe weight loss and pancytopenia. Both the specific DNAs of human beta-globin DNA gene and the murine RAPSYN gene were detected in the hu-NOD/SCID chimeras; The survival rate was 14% at 6 weeks posttransplantation. The engrafted human cells consisted mainly of CD3+ T lymphocytes but CD4/CD8 ratios seemed inverted in the chimeras. The xenogeneic graft versus host reaction was heterogeneous in different organs mainly with human lymphocytes infiltration and the liver and lungs were the critical organs. CONCLUSION: Mobilized peripheral blood mononuclear cells are capable of engrafting in irradiated NOD/SCID mice with induced acute X-GVHD syndrome. The liver and the lungs are the critical organs. This is a good model for investigating the effects of human cells in inducing acute graft versus host disease in animal and for testing effective intervention methodology.