脾细胞移植诱导大鼠小肠移植微嵌合体形成的实验研究

The formation of chimerism in rat small bowel transplantation by splenocyte infusion

目的研究脾细胞输注移植促进微嵌合体形成与大鼠小肠移植免疫耐受的关系。方法制备供体大鼠的脾细胞悬液,于移植前四周将脾细胞悬液经舌静脉注入受体大鼠体内,行同种异体节段性小肠移植,PCR技术检测雌性受体外周血及皮肤Y染色体特异性DNA片段证实微嵌合体形成,通过移植肠段病理组织学变化观察急性排斥反应与微嵌合体形成的关系。结果大鼠接受小肠移植后的存活时间显示,对照组移植后平均存活时间为7.1±1.2d,显著少于实验组的18.4±3.6d(P<0.05),差异具有统计学意义。预先经脾细胞输注的实验组小肠移植受体的微嵌合体检出率高于对照组;嵌合体阳性的受体急性排斥反应较嵌合体阴性者轻。结论脾细胞输注移植可促进小肠移植嵌合体形成,微嵌合体形成可诱导大鼠小肠移植的免疫耐受。

Objective To study the relationship between chimerism induced by infusing donor splenocyte and immunologic tolerance of small bowel transplantation in rat. Methods The prepared donor splenocytes were infused into recipient via lingual vein four weeks before establishment of allogeneic segmental small bowel transplantation heterotopically in rats. the specific DNA fragment of Y chromosome was detect in peripheral blood and skin by Polymerase Chain Reaction technique after operation. The relationship be- tween chimerism and acute rejection was evaluated by histopathology examination. Results The survival time after small bowel trans--plantation was 7.1± 1.2 d in control group, 18.4±3.6 d in experimental group. The survival time was significant longer （ P 〈0.05） in experimental group than in control group. The chimerism in the experimental group is higher than control group. The acute rejection in the group with positive chimerism is mild than that of negative. Conclusion The infusion of donor splenocyte promotes the formation of chimerism and chimerism may induces specific immunologictolerance in small bow- el transplantation of rat.