异柠檬酸脱氢酶调控CD4+T细胞Foxp3表达影响原发性胆汁性胆管炎进展的机制研究

原发性胆汁性胆管炎（PBC）是一种渐进性自身免疫性肝病，目前缺乏精准监测病程的标志物。前期证实CD4+T细胞异常分化促进PBC炎症发展，但决定CD4+T细胞分化的Foxp3表达调控机制不明。临床发现PBC患者异柠檬酸脱氢酶(IDH)水平降低与Foxp3低表达及病情进展相关，提示IDH参与调控CD4+T细胞分化。项目拟检测PBC患者外周血、肝组织中IDH表达、Treg/Th17比例、炎症因子水平以及Foxp3表达及甲基化水平，通过上调CD4+T细胞IDH水平、沉默TET/TGF-βR/Foxp3基因表达观察Foxp3水平，并应用CD4-tLNPs-hc/shRNA靶向调控PBC小鼠CD4+T细胞IDH表达，动态观察IDH对PBC疾病进程的影响，阐明IDH通过α-KG/TET、TGF-βR/Smads双通路调控Foxp3表达影响PBC炎症进展的分子机制，为PBC病程监测提供新靶标。

Primary biliary cholangitis (PBC) is an progressive autoimmune liver disease. Nowadays,there is no good biomarker to monitor disease progression precisely. Our previous research results show that abnormal differentiation of CD4+ T lymphocytes are involved in intrahepatic inflammatory deterioration in the PBC patients . The stable and high expression of Foxp3 can regulate the differentiation of CD4+T lymphocytes, but the mechanism is unclear. We found that decreased level of isocitrate dehydrogenase(IDH ) in PBC patients was associated with decreased expression of Foxp3 and increased inflammation indexes. This indicates that IDH might regulate the differentiation of CD4+T lymphocytes. In this study, we use peripheral blood 、liver biopsy tissues of PBC patients to examine the expression of IDH and Foxp3、the levels of related cytokines、the levels of Foxp3 gene methylation and Treg/Th17 ratio. To further reseach the molecular mechanism of IDH regulating the expression of Foxp3，in vitro experiments are carried out to observe the changes of Foxp3 expression before and after upregulating IDH level and silencing TET/TGF-βR/Foxp3 gene expression, in vivo tests are through injecting CD4-tLNPs-hc/shRNA to PBC mices to observe the relationship between IDH and disease progression dynamically. The reseach will elucidate that IDH relieve immune inflammation by regulating Foxp3 expression based on attenuating Foxp3 gene methylation and enhancing α-KG/TET and TGF-βR/Smads signal pathes. It will provide theoretical basis for elucidating the immune inflammation of PBC and finding new biomarker and target for monitoring development of PBC.