Th1/Th2细胞因子变化在大鼠肝移植免疫耐受中的作用

目的:研究大鼠肝移植术后移植肝和外周血中细胞因子的表达,并分析其在急性排异反应和耐受诱导中的作用。方法:Kamada法建立大鼠肝移植模型,并随机分为4组,每组8只。A组:同品系组;B组:免疫排异组;C组:B组+免疫抑制剂;D组:C组+骨髓输注。RT-PCR和ELISA技术分别检测移植肝和外周血中细胞因子IL-2、INF-γ、IL-4、IL-10、TGF-β1的表达,并观察受体存活率。结果:在B组中Th1型细胞因子(IL-2、INF-γ)表达高于A、C和D组(P<0.05);而Th2型细胞因子(IL-4、IL-10)和TGF-β1表达低于C和D组(P<0.05);细胞因子在C组与D组大鼠中的表达无统计学差异。A、C、D组大鼠术后近、远期存活率明显优于B组。结论:Th1型细胞因子(IL-2、INF-γ)参与肝移植急性排异反应的发生,Th2型细胞因子(IL-4、IL-10)和TGF-β1可能参与移植物免疫耐受的诱导,延长移植物存活。

Role of the changes of Thlfrh2 cytokines in the immune tolerance after liver transplantation in rats

Objective To investigate the role of the Th1/Th2 cytokines expressed in grafts and bloods in the immune tolerance after liver transplantation in rats. Methods According to Kamada methods, we established the animal model of liver transplantation, and divided into four groups： group A, the homologous rats; group B, the nonhomologous ones; group C, based on the group B, group C, based on the group B, the immunosuppressor was usded after operation; group D, based on the group C, donor bone marrow was transfused. Samples were taken from eight allografts at the six days postoperative in every group. The RT-PCR and ELISA technique were used to detect cytokines expression of IL-2 INF-γ,IL-4,IL-10,TGF-β1 in grafts and peripheral bloods after liver transplantation. The survival rate was observed. Results The expression of Thl cytokines （IL-2, INF-γ） were much higher in group B than in group A,C and D （P〈 0.05）. The expression of Th2 cytokines （IL-4.IL-10）, TGF-131 were much lower in group B than in group C and D （P〈 0.05）. And there were no significant difference between group C and D. The survival rate after liver transplantation in group A,C and D were higher than in group B. Conclusions These findings confirmed that Thl cytokines （IL-2.INF-γ） are specifically involved in liver acute rejection, while Th2 cytokines （IL-4.IL-10） and TGF-β1 may play roles in immune responses leading to graft tolerance and promoting survival rate.