基于“组学”策略系统解析原发性胆汁性肝硬化疾病相关基因位点的作用机理研究

Primary biliary cirrhosis (PBC) is a chronic autoimmune cholestatic liver disease, with the manifestation of destruction of intrahepatic lobular and medium size bile duct. It is an organ-specific autoimmune liver disease. With the processing of PBC, the final PBC patients will inevitably appear the serious complications of liver failure and cirrhosis. Its pathogenesis has not been clearly elucidated. Evidences suggesting that it is a complex disease with both autoimmune and genetic factors involved. It cannot be ignored that the genetic factors' crucial role in the pathogenesis of PBC. The GWAS study had found about 23 PBC-related genes; however, the disease-related loci and its mechanism are still unclear. In order to systemically analyze the mechanism of the PBC disease-related loci, the project uses an "Omics" strategy to resolve the relevant SNP transcription factor, target genes and cell-specific expression, whose specific research methods mainly include MassArray iPEX, Sanger sequencing, immune co-precipitation (CHIP), flow cytometry and related bioinformatics analysis. It is extremely vital for our understanding of PBC pathogenesis, assessment of disease risk and drug development.

原发性胆汁性肝硬化（PBC）是一种与自身免疫有关的慢性进行性胆汁淤积性肝脏疾病，是以破坏肝内小叶及中等大小胆管为主的器官特异性自身免疫性肝病。终末期PBC患者不可避免地出现肝功能衰竭和肝硬化等严重并发症。PBC的发病机制尚未阐明。现有的一系列证据提示其是自身免疫与遗传易感性双重作用的结果，而遗传因素在PBC的发病环节中起了至关重要的作用。虽然GWAS研究发现了约23个PBC相关基因，然其致病位点及作用机制尚不清楚。为了系统的解析PBC疾病相关基因位点的作用机制，本项目采用"组学"策略对PBC相关SNP的转录因子、靶基因及细胞特异性表达进行系统性分析，具体的研究手段包括：MassArray ipex基因分型、Sanger测序、免疫共沉淀（CHIP）、流式细胞术等实验技术及相应的生物信息学分析，以确定PBC相关SNP调节靶基因表达水平的作用方式及其发挥作用的细胞类型，这对了解PBC的发病过程。

原发性胆汁性肝硬化（PBC）是一种与自身免疫有关的慢性进行性胆汁淤积性疾病。虽然目前PBC的发病机制尚不清晰，但普遍认为其是一种多基因共同作用的复杂疾病。遗传因素在PBC的发病中起了至关重要的作用。GWAS研究发现了数十个PBC相关基因，但其致病位点及作用机理尚不清晰。为系统的解析PBC相关位点的作用机理，本项目确证了IL12A、IL7R、HELZ2及LYN和中国汉族人群的PBC相关性。其中IL12A、HELZ2及LYN首次发现和中国汉族人群的PBC相关。并进一步探究了IL12A相关SNP的作用机制，发现IL12A相关的SNP位于增强子区域，可上调IL12A基因的表达。IL7R相关的SNP位点位于基因的启动子区，可调节IL7R基因的转录。通过3C及捕获测序技术，进一步阐明了不同染色体的调控元件之间的相关作用。本实验发现HLA区域的相互作用最为密集。本项目的开展为进一步阐明PBC的发病机制提供了思路，对PBC的早期诊断及治疗提供了线索。