肝细胞移植治疗急性肝功能衰竭的免疫排斥研究

Investigation of Immunological Rejection after Hepatocyte Transplantation for Acute Liver Failure in Animals

目的研究肝细胞腹腔移植治疗急性肝功能衰竭的免疫排斥反应。方法用胶原酶灌注法分离幼猪及BALB/c和C57BL/6小鼠肝细胞;用腹腔注射CCl4的方法建立C57BL/6急性肝功能衰竭模型;将实验动物分为同基因移植组、同种异基因移植组和异种移植组。各组动物肝细胞移植入急性肝功能衰竭小鼠腹腔内,观察受体小鼠存活情况,比较各组动物T细胞亚群、免疫球蛋白水平和细胞因子的变化。结果①受体小鼠存活情况:同基因移植组为8/10,同种异基因移植组为6/10,异种移植组为3/10,同基因移植组和同种异基因移植组受体的生存情况明显好于异种移植组(P<0.05)。②T细胞亚群变化:移植后7 d内,同基因移植组外周血中CD4+和CD8+T细胞均无明显变化,同种异基因移植组CD4+T细胞于移植后3 d时达高峰(P<0.05),而CD8+T细胞7 d内无明显变化,异种移植组CD4+和CD8+T细胞移植后7 d内均明显升高,且于移植后3 d时达高峰(P<0.05)。③免疫球蛋白水平:同基因移植组血清免疫球蛋白IgM和IgG水平在移植后0.5、1和3 d时未见明显变化,同种异基因移植组和异种移植组的IgM在移植后1 d时达高峰(P<0.05),而IgG在移植后3 d时达高峰(P<0.05)。④血清细胞因子水平:移植后7 d,同种异基因移植组和异种移植组的IFN-γ、TNF-α及IL-2血清浓度明显高于同基因移植组(P<0.05);异种移植组的IL-6血清浓度明显高于同基因移植组和同种异基因移植组(P<0.05)。结论无论同种还是异种肝细胞移植,初期均发生了强烈的CD4+及CD8+T细胞参与的细胞免疫和较强体液免疫反应。

Objective To investigate the immunological rejection after hepatocyte transplantation for acute liver failure（ALF） in mice.Methods The hepatocytes were isolated from pig,BALB/c and C57BL/6 mice livers were conducted and then transplanted into C57BL/6 mice.CCl4 was used to make ALF mice model.The experimental animals were randomly divided into three groups,including syngenic group,allogeneic group,and xenogenic group.The survival statuses of all the mice were recorded.The alteration of T lymphocyte subsets,immune globulin,and cytokine were determined.Results ①The survival ratio was 8/10,6/10,and 3/10 in the syngenic group,allogeneic group,and xenogenic group,respectively.The survival ratio in the syngenic group was significantly higher than that in the other two groups（P0.05）.②The CD4＋ and CD8＋ T cells of the peripheral blood in the syngenic group did not change significantly on week one after transplantation.The CD4＋ T cells in the allogeneic group reached the peak on day 3 after hepatocyte transplantation（P0.05）,while CD8＋ T cells did not change much in one week.The CD4＋ and CD8＋ T cells in the xenogenic group increased and reached the peak on day 3 after transplantation（P0.05）.③There were no significantly differences of IgM and IgG in the syngenic group among 0.5,1,and 3 d after transplantation.IgM of the allogeneic group and xenogenic group reached the peak on day 1（P0.05） and IgG reached the peak on day 3（P0.05） after transplantation.④The concentrations of IFN-γ,TNF-ɑ,and IL-2 in the allogeneic group and xenogenic group were significantly higher than those in the syngenic group（P0.05）.The concentration of IL-6 of the xenogenic group was higher than that of the other two groups（P0.05）.ConclusionsCD4＋ and CD8＋ T cells play an important role in immune response to both allogeneic and xenogenic hepatocyte transplantation,as well as induce humoral immune response early after hepatocyte transplantation.