The immunopathogenesis and the regulation of hepatic lesions in murine model of primary biliary cirrhosis.

我们以前曾报道，由于主要组织相容性复合体(MHC)类[差异]，在移植物抗宿主反应(GVHR)的小鼠中，CD4^+T细胞诱导的原发性胆汁性肝硬变(PBC)样肝损害。本研究旨在探讨CD_4~+T细胞产生的细胞因子与肝脏病变形成的关系。在GVHR诱导后的不同时间点，用流式细胞仪分选肝脏中的CD4~+T细胞，检测其细胞因子mRNA的表达。此外，我们还检测了在抗黏附分子抗体抑制病变的过程中，Th1/Th2平衡是否会发生变化。L)组织学上，从第5天开始，胆管周围可见CD_4~+T细胞的浸润，至第14天，病变逐渐加重。第14天，胆管周围可见CD_8~+、B220~+、Mac-L~+T细胞以及CD_4~+T细胞。在肝脏中浸润性的CD4^-T细胞。…观察Th1型细胞因子干扰素-γ的表达水平第14天血清AMA水平显著高于5.2天。HE染色显示抗VLA-4抗体组和抗VCAM-1抗体组门脉细胞浸润程度均明显高于对照组(P<0.05)，仅抗VLA-4抗体组与正常对照组比较差异无统计学意义(P>0.05)。IL-2、IFN-γ、IL-4、IL-10mRNA在各组中的表达无明显变化。免疫组织化学显示，各组均可见CD4、CD8、B220或Mac-1阳性细胞。在NSDC病变出现前的早期，Th1细胞的表达升高，提示Th1细胞可能与PBC的发病有关。IL-10 m RNA的延迟表达可能反映了肝脏Th1细胞产生细胞因子的抑制。此外，应用抗VLA-4抗体可减少PBC动物模型门脉细胞的浸润。而肝脏浸润性Thyl.2~+、CD_4~+细胞的细胞因子谱及细胞成分未见明显改变。这些结果表明，给予抗黏附分子抗体可能抑制PBC样病变，而不是Th1/Th2平衡。较少

We have previously reported that CD4^+ T cells induced primary biliary cirrhosis (PBC) Iike hepatic lesions in mice with graft-versus-host reaction (GVHR) due to major histocompatibility complex (MHC) class [[disparity. In this srudy, to ciarify the relationship between the cytokine profile produced by CD4^+ T cells and the formation of hepatic lesions. we sorted CD4^+ T cells from the liver using flowcytometer and examined their cytokine mRNA expressions at various time points after GVHR induction. Furthermore, we examined wheather Th1/Th2 balance might change during the suppression of lesions by antibodies against adhesion molecules. l) Histologically, the infiltration of CD4^+ T cells around the bile ducts was observed from day 5, and the lesions deteriorated gradually untii day 14. On day 14, CD8^-, B220^+ and Mac-l^+ cells, as well as CD4^+ T cells around the bile ducts were seen. In the liver infiltrating CD4^- T cells. the expression level of Th1 cytokine IFN-gamma mRNA was obse … More rved to increae at an early phase day 3, whereas that of Th2 cytokine IL-l0 mRNA was elevated at a later phase day 14. Serum levels of AMA on day 14 were significantly higher than that on day 5.2) H.E.staining showed the grade of portal cellular infiltration both in groups administered anti-VLA-4 antibodies and anti-VCAM-1 antibodies and only anti-VLA-4 antibodies were significantly suppressed compared to the control adminstered normal rat lgG.The induction of GVHR and the elevation of AMA were not alterd in these groups by administering monoclonal antibodies. The expressions of IL-2, IFNgamma, IL-4 and IL-l0 mRNA were not changed in these groups. Immunohistochemically, CD4, CD8, B220 or Mac-1 positive cells were detected in these groups. The elevation of IFN-gamma mRNA expression in the early phase before the appearance of NSDC lesions suggest that Th1 cells may be related to the pathogenesis of PBC in this model. Delayd expression of IL-l0 mRNA may reflect the suppression of cytokine production by Th1 cells in the liver. Moreover, the portal cellular infiltration in PBC animal model Is reduced by the administration of antibodies against VLA-4. However, cytokine profile of liver infiltrating Thyl.2^+CD4^+ lymphocytes and the composition of infiltrating cells were not changed. These results suggest that the administration of antibodies against adhision molecule may suppress PBC Iike lesions without Th1/Th2 balance. Less