iTr35细胞是最新鉴定出的一类以分泌IL-35为主的新型调节性T细胞，外源性IL-35或nTreg分泌的IL-35均能促进iTr35细胞的生成；iTr35细胞主要通过IL-35发挥抑制性作用；在慢性乙型肝炎的研究中，目前尚无关于iTr35细胞和IL-35在HBV感染慢性化、免疫耐受形成和病毒持续感染中的作用和机制研究报道，本课题组首次将HBV感染慢性化及免疫耐受形成与iTr35细胞和IL-35的功能联系起来。本项目拟采用慢乙肝患者及HBV转基因小鼠的外周血和肝组织标本，分析慢性乙肝患者不同炎症期iTr35细胞在外周血中的频数和功能，以及它们在肝内的浸润程度与HBV感染病程进展的关系，并深入分析iTr35细胞和IL-35相在HBV感染慢性化中的作用与机制，为乙型肝炎的免疫治疗策略提供新的思路和方法。

iTr35 cell is a newly identified regulatory T cell which mainly produces IL-35. Exogenous IL-35 or nTreg cells producing IL-35 can promote the generation of iTr35 cells. iTr35 cells mediate suppression mainly via IL-35. In the field of hepatitis B, there are no reports on iTr35 cells and IL-35 in the chronicity of HBV infection, the development of immune tolerance and persistance of HBV infection. Our group is the first, to our knowlege, to combine the chronicity of HBV infection and the development of immune tolerance with the function of iTr35 cells and IL-35. This project is proposed to investigate the frequency and function of iTr35 cells in chronic hepatitis B patients with different inflammatory phrases using peripheral blood and liver tissues from patients and transgenic mice, as well as the relationship between intrahepatic infiltration degree and disease progression and iTr35 cells and IL-35. The role and mechanism of iTr35 cells and IL-35 in chronic hepatitis B virus infeciton will be intensively studied in order to develop new immunotherapeutic strategies for treating hepatitis B.