致敏动物模型的建立及其对造血干细胞植入的影响

Establishment of Sensitized Animal Models and Their Sensitization Effects on Engraftment of Hematopoietic Stem Cells

本研究目的是建立致敏的动物模型,探索致敏动物体内免疫功能的改变,并探讨致敏对造血干细胞植入的影响。经尾静脉分别输注不同数量的C57BL/6脾细胞(1×105、1×106、1×106,连续注射2次,间隔7天)于BALB/c小鼠,通过补体依赖淋巴细胞毒性实验、混合淋巴细胞反应和ELISA等方法检测致敏模型的免疫功能。致敏BALB/c模型经8Gy60Coγ-线照射后通过尾静脉或骨髓腔移植1×107C57BL/6骨髓细胞,观察移植后生存情况。结果表明:致敏BALB/c模型均产生不同强度的供者反应性抗体,1×106及1×106连续注射2次,间隔1周的致敏组脾细胞体外增殖均明显高于正常小鼠。各组致敏模型小鼠经尾静脉注射C57BL/6骨髓细胞后,均于移植后第9-15天死亡,1×106连续注射2次,间隔1周的致敏BALB/c模型经骨髓腔注射骨髓细胞后亦于2周内死亡。结论:通过同种异基因的脾细胞输注建立不同致敏程度的动物模型,该致敏模型小鼠体内免疫功能的变化与致敏程度有关。脾细胞输注致敏使受者对供者造血干细胞产生排斥作用,而骨髓腔注射方法并不能改善植入。

This study was aimed to establish sensitized animal models, explore the changes of immune function in these sensitized recipients, and investigate effects of sensitization on the engraftment of hematopoietic stem cells （HSCs）. Different doses of spleen cells （ 1 ×10^5, 1 ×10^6 and 1 ×10^6× 2 at intervals of 7 days ） from C57BL/6 were infused into BALB/c, the immunity function of sensitized models was tested by complement-dependent cytotoxicity method, mixed lymphocyte reaction and ELISA. After irradiation with γ-ray of ^60Co in dose 8 Gy, sensitized mice were transplanted 1 × 10^7 C57BL/6 bone marrow cells via tail vein or intra-bone marrow, and survival rate was detected daily. The results showed that different levels of donor reactive antibody were induced in all sensitized models. Comparing with normal mice, profound proliferation of spleen cells were found in groups of injected 1 × 10^6 and 1 × 10^6, continuous injections at intervals of 7 days. Sensitized model received bone marrow cells of C57BL/6 via tail vein died on day 10 to 14 after transplantation, and sensitized model mice received bone marrow cells of 1 × 10^6 × 2 at intervals of 7 days via intra-bone marrow also died within two weeks after transplantation. It is concluded that different sensitized mouse models are established by different doses of allogeneic spleen cells infusion, the changes of immune function in sensitized mice are correlative with sensitization. Donor HSCs are rejected in sensitized models, and the engraftment can not be improved by intra-bone marrow injection.