肝脏新型天然淋巴细胞亚群的鉴定及其在慢性乙肝进展中的调节机制研究

Liver is characterized by its unique immune tolerance, which has been demonstrated to associate with the frequent occurrence, occult and chronicity of liver diseases. So it is of importance to finding liver unique lymphoid cells and identifying their immunological properties. Innate lymphoid cells (ILCs) are newly identified immune cell population. ILCs have been found to be characterized by tissue-specific distribution and correlated with the development and progression of several human diseases. However, it remains unknown whether there is a population of liver-specific ILC subsets and their immunological characteristics are also needed to be addressed. Recently, we found that a subset of CD56+ ILC1 in human liver, which is different from previously reported splenic ILC3 and classical natural killer (NK) cells and indicated relatively liver-specific distribution. Therefore, in this study, we will comprehensively characterize these CD56+ ILC1 cells through high-through RNA-seq and multicolor FACS analysis, and also compare the difference of these cells in various immune organs including liver, spleen and peripheral blood. We will also investigate the dynamic of these cells in disease progression of chronic hepatitis with HBV infection and address which pathogenic/inflammatory factors possibly regulate these cells and which cells could be regulated by these cells. Thus, this study will identify a novel cell population of liver-specific CD56+ ILC1 and investigate their functional role during the disease progression of liver inflammation with chronic HBV infection. These data will highlight CD56+ ILC1 as a new therapeutic target of anti-inflammation in liver diseases, particularly in chronic HBV infection.

肝脏具有独特的免疫耐受特征，因而与肝病的高发、隐匿、迁延等特征密切相关；发现肝脏独特的淋巴细胞亚群并阐明其免疫学特性具有重要的理论和实用价值。天然淋巴细胞（innate lymphoid cells,ILCs）是新近鉴定的一群新型免疫细胞，具有组织分布特异性，与多种疾病的发生发展密切相关，但其在肝脏中的分类及免疫特性还未被鉴定。我们最近发现：肝脏含有一群特异的CD56+ILC1细胞，不同于已鉴定的脾脏ILC3和经典的NK亚群。我们将进一步通过多色流式和RNA-seq技术深入鉴定这群细胞独特的免疫学特性；同时，我们将以慢性乙肝肝损伤长期随访患者为研究对象，阐明疾病状态下该群细胞的变化特点及其调节机制，最终阐明这群细胞与疾病进展的关系。该研究将发现一群肝脏独特的免疫细胞，阐明它们在慢性乙肝进展中的功能及分子机制，为今后针对肝脏设计新的抗炎治疗靶点提出新思路。

发现并鉴定肝脏内特异淋巴细胞亚群对于理解肝脏免疫学、阐明肝脏相关疾病发生机制、建立新的治疗手段具有重要科学意义。本项目研究内容包括：（1）发现人体组织器官新型天然免疫细胞亚群，并鉴定其基本免疫学特性；（2）以人类病毒慢性感染损伤为疾病模型，阐明上述天然免疫细胞亚群的变化特点。上述研究将为寻找关键的致病细胞和分子提供依据，也为今后针对人体固有天然淋巴细胞设计新的治疗靶点提出更多的思路。.主要结果如下：（1）建立人免疫器官组织标本库：目前已建立了从移植供者肝脏灌洗液、脾脏、肠道、骨髓、淋巴结等中获取淋巴细胞的标本处理平台，标准化保存标本1000余份；建立了200多例肝硬化长期随访队列和标本库，并标准化保存了外周血、门脉血以及脾脏淋巴细胞，以及部分肝脏组织。（2）发现HBV相关肝硬化病人肝脏NK细胞抗纤维化功能损伤特点，阐明肝脏星型细胞通过cell-in-cell方式诱导NK细胞凋亡的分子机制，揭示了NK细胞在肝纤维化进展的分子调节机制，为临床干预肝纤维化提供了新型治疗策略。鉴定组织CD4+ILC1新亚群，证实该亚群是HIV新的病毒储藏库，阐明了该亚群在HIV慢性感染中的变化特点和功能意义。（3）建立了高通量组学研究组织区域免疫的技术方法，利用单细胞测序、RNAseq以及蛋白质组学等手段，正着力描绘人体重要组织脏器免疫细胞图谱，并聚焦到天然淋巴细胞在病毒慢性感染中作用机制，可为后续重大研究计划提供基本的组织特异性淋巴细胞图谱。.研究目标已完成，部分研究正在进行，主要成果如下：（1）发表SCI论文3篇，国内外大会发言5次，申请获得软件著作权3项。（2）建立特色生物样本库及临床数据库各1个，标本库容量25万份。（3）培养博士研究生4名，硕士研究生4名，博士后2名；在读博士研究生2名，硕士研究生2名，博士后1名。1人次获得国家自然科学基金创新群体骨干，国家百万千人才工程称号及全军拔尖人才培养对象。（4）部分研究成果获得教育部科技进步一等奖和山东省科技进步二等奖。