肝星状细胞在乙型重型肝炎中对Th17/Treg平衡的调控作用及机制研究

The balance between pro-inflammatory Th17 and suppressing Treg is important for the incidence of severe hepatitis B, however, the regulation of Th17/Treg balance has not been fully elucidated. It is recently established that activated hepatic stellate cells have the characteristics of a variety of immune cells, and play a key role in the local immune regulation of the liver. Our previous studies have shown that the expansion of Th17 and Treg in liver is regulated by the local inflammatory factors in situ. Our latest studies show that hepatic stellate cells from patients with severe hepatitis B took on an activate phenotype, which could produce abundant of inflammatory factors, making it a potential source for the regulation of Th17/Treg balance. Base on the above findings,this project first intends to investigate the regulation of Th17/Treg balance by hepatic stellate cells,in the context of the dynamic changes of Th17/Treg in different stages of severe hepatitis B. We will then screen and verify of the key target molecule by cytokines chip and blocking experiments in a primary cells coculture model. By the use of clinical samples, the corelation between the target molecule,Th17/Treg and disease progression would further be analysesd. The expected results may not only reveal the regulatory mechanism of Th17/Treg balance in severe hepatitis B from a new perspective of hepatic stellate cells, but also provide a theoretical basis for the development of the early diagnosis, prediction of outcome and a novel therapy for severe hepatitis B.

促炎Th17与抑炎Treg比率失衡是乙型重型肝炎发病的关键环节，但调控Th17/Treg平衡的机制尚未阐明；近年发现活化的肝星状细胞在肝脏局部免疫调控中发挥重要作用。我们之前研究表明：肝脏中Th17和Treg的扩增主要受到局部炎症因子影响。我们最新发现：乙型重型肝炎中肝星状细胞呈活化状态并分泌大量炎症因子，是调节Th17/Treg平衡潜在的新来源。以此为基础，本课题拟结合乙型重型肝炎病情进展不同时期Th17/Treg动态变化，系统研究活化肝星状细胞对Th17/Treg平衡的影响；建立原代细胞共培养模型，通过液相芯片和阻断实验，筛选并验证其中关键的靶标分子及其作用机制；运用临床样品，分析该靶标分子与Th17/Treg及病情进展的关系。其创新及意义在于：从肝星状细胞这一崭新角度揭示乙型重型肝炎中Th17/Treg平衡受调控的机制，为研制以之为靶标的早期诊断、预测归转和新型防治手段提供理论基础。

免疫失衡是重型肝炎发病的关键环节，但调控重型肝炎免疫平衡的机制尚未阐明；近年发现活化肝星状细胞HSC在肝脏局部免疫调控中发挥重要作用。课题组前期研究表明：乙型重型肝炎中HSC呈活化状态并分泌大量炎症因子，是调节免疫平衡潜在的新来源。以此为基础，本项目结合乙型重型肝炎病情进展不同时期Th17/Treg比率、NK、单核细胞的功能等，研究活化肝星状细胞对这些免疫细胞的影响。本项目按计划执行，发现：1、乙型重型肝炎中HSC能够通过PGE2和IL-6促进CD4T细胞向Th17和Treg细胞分化；2、乙型重型肝炎患者Th17/Treg比例的变化与病情进展相关：缓解期患者Th17/Treg比率升高，而进展期的患者的没有显著变化；3、除了完成预期，我们还发现乙型重型肝炎中的NK、单核细胞等免疫细胞的数量和功能都有不同程度的变化，活化HSC对NK、单核细胞的表型和功能有调节作用；4、深入拓展研究了炎症环境下单核细胞通过microRNA调节肝纤维化的分子机制。其创新及意义在于：从肝星状细胞这一崭新角度揭示重型肝炎中Th17/Treg、NK、单核细胞受调控的机制，为重肝诊治提供理论基础。研究结果发表SCI论文8篇（均标注），培养博士生1名，项目负责人获得了广东省自然基金项目1项和入选了中山大学附属第三医院杰出青年后备人才计划。