异种移植“体液适应”的诱导及其机制

The induction of humoral accommodation and its mechanism of xenotransplantation

目的：诱导异种移植“体液适应”，并对其机制加以研究．方法：运用多种免疫抑制方法处理受体兔，然后行大鼠→兔骨髓、胸腺联合移植，并通过细胞毒试验、直接和间接免疫荧光染色等方法检测大鼠组织、细胞在受体兔体内的嵌合性；同时，荧光标记的羊抗大鼠单个核细胞抗体直接大鼠体内注射，通过流式细胞仪对大鼠淋巴细胞和中性粒细胞的数量及平均荧光强度进行动态监测．结果：模型兔血清对供体的细胞毒性无降低，但供体大鼠胸腺和单个核细胞能与受体兔抗大鼠抗体长期共存；大鼠在注射抗体后的１０ｍｉｎ～２０ｍｉｎ内细胞的平均荧光强度迅速下降．结论：受体体内的抗供体抗体并不明显影响供体组织或细胞在受体中的存活，即受体和移植物相互适应；其机制可能是移植细胞表面的抗原抗体复合物脱落导致细胞表面相应抗原缺失．

AIM: To induce humoral accommodation of xenotransplantation and to study its mechanism. METHODS: Ratrabbit bone marrow and thymus combined transplantation was performed after the recipients were treated with various wellselected immunosuppression methods and then the chimerism of the models was detected by means of lymphocyte toxicity test, direct and indirect immunofluorometry. Meanwhile, the number and the mean superficial fluorescence intensity of lymphocyte and neutrophil of the rats were monitored dynamically when fluorescencelabelled goat antirat antibody was injected into the rats directly. RESULTS: The action of the lymphocyte toxicity of recipient's serum was enhanced while the donor's mononuclear cells and the antidonor antibodies coexisted in the recipient for a long time. The mean superficial fluorescence intensity of cells decreased rapidly during 10￣20 minutes after the injection. CONCLUSION: The antidonor antibodies may not be the key element to influence the survival of tissues and cells of donors and the donor's mononuclear cells and the antidonor antibodies can coexist with each other, which suggests the adaptation or accommodation of either donor's or recipients' tissue and cells. The mechanism of this phenomenon may be the loss of corresponding antigen on the cell surface caused by the exfoliation of the complex of antigens and antibodies.