【摘要】 目的 依据T细胞的发育机制理论，诱导针对移植物特抗原的异性免疫耐受。方法 先用致死剂量的γ射线，将受者的T细胞及干细胞去除，形成了一个不具干细胞、前T细胞和T细胞的受者模型，称受者模型Ⅰ。同时经同种皮肤移植制造正常的受者对供者器官的免疫排斥反应的模型，称模型Ⅱ。从模型Ⅱ中经免疫磁珠分选取得被供者抗原所激活的、具有抗原提呈功能的树突状细胞，与正常的事先准备好的受者骨髓细胞在体外混合后回输至受者模型Ⅰ中。受者Ⅰ完成免疫造血功能重建后，再对其行同种皮肤移植。分5组，分别观察移植皮片的存活时间，并常规病理组织切片和流式细胞分析检测。结果 由T细胞发育的上游诱导产生特异性的免疫移植耐受，比较对照组，实验组皮片存活时间显著延长(P<0.005)，流式细胞分析和病理组织学分析差异也有显著性。结论 在所建立的模型和系统中，能诱导移植物特异性的免疫耐受，也进一步验证了胸腺的阴性选择理论。

     【关键词】 树突状细胞； 移植； 耐受； 胸腺； T细胞发育

    Induction of transplantation tolerance with allograft-activated host dendritic cells

    XU Qi-qi，LI Mei，WANG Song-xia,et al.Department of Immunology，Peking University Health Science Center，Beijing 100083,China

    【Abstract】 Objective The negative thymic selection is critical for the maturation of bone marrow derived cells to T cells.Negative selection occurs in thymic medulla and is normally mediated by bone marrow derived APC，like dendritic cells (DC) or macrophages.Immunodominant allopeptide-pulsed host dendritic cells can successfully induce transplantation tolerance.Methods Host dendritic cells were activated by allo-skin transplantation on day -10 to present the donor-specific antigens.Murine recipients of allogeneic skin grafts on day 0 were given transfusion of these activated dendritic cells and isogeneic bone marrow cells after lethal irradiation.Results Transfusion of donor-antigen-specific activated host dendritic cells plus isogeneic bone marrow cells led to prolonged skin allograft survival in recipients treated with lethal irradiation.In contrast ......