A new humanized mouse model of chronic hepatitis B

项目摘要 慢性B型肝炎病毒（HBV）感染是一个重要的全球性健康问题，因为它实质上 增加了患肝硬化和肝细胞癌的风险。全球超过240家 有100万人慢性感染HBV，这种病毒的感染占所有肝脏感染的~ 80 癌人体免疫系统可以从肝脏中清除HBV，但通常无法做到这一点，特别是在 那些在很小的时候就被感染的人。乙肝病毒的持续存在部分是由于免疫回避策略 在慢性感染期间，病毒以及宿主驱动的抗病毒免疫应答的免疫抑制 用于限制炎症和免疫病理学的感染。因此，抗病毒药物的治疗操作 T细胞反应代表了治愈感染的有希望的治疗方法。然而，缺乏合适的 评估新的免疫方法的模型系统是免疫学研究的关键障碍。 领域该提案的总体目标是开发一种新的HBV小鼠模型， 人类免疫系统与遗传定义的便利性和可重复性的相关性 转基因小鼠我们的一般方法是将联合收割机结合起来， 一种新的“人源化”小鼠，其免疫系统可以有效地用T细胞重建， HBV感染者。然后我们将检验人类免疫细胞在这些小鼠体内的植入 将导致肝脏中的HBV特异性免疫应答，并且这种应答将反映疾病状态 人类捐赠者的名字为了评估我们的假设，我们将实现两个具体目标。首先我们将介绍 HBV复制到含有许多敲入基因人源化的小鼠品系的肝脏中， 改善动物体内人造血细胞群的植入、分化和维持。 其次，我们将这些小鼠与来自急性消退和慢性HBV患者的PBMC移植， 描述这些免疫细胞如何运输到肝脏并对产生HBV的肝细胞做出反应 抗原建立该模型系统的目的是为研究人类HBV提供新的手段 体内免疫反应。这将填补一个关键的未满足的需求，我们预计，这一系统将有广泛的 应用基础和转化HBV研究来了解慢性HBV中的T细胞功能 感染，评估新的免疫方法，并确定HBV的决定因素 免疫发病机制这种分析可能对慢性炎症的研究和治疗产生重大影响。 人类的肝脏感染

PROJECT SUMMARY Chronic hepatitis B virus (HBV) infection is a significant global health problem because it substantially increases the risk for developing liver cirrhosis and hepatocellular carcinoma. Worldwide, more than 240 million people are chronically infected with HBV, and infection with this virus accounts for ~80% of all liver cancer. The human immune system can eliminate HBV from the liver, yet often fails to do so, especially in those who become infected at an early age. HBV persistence is due in part to immunoevasive tactics employed by the virus as well as host-driven immunosuppression of antiviral immune responses during chronic infection that serves to limit inflammation and immunopathology. Thus, therapeutic manipulation of the antiviral T cell response represents a promising method of treatment to cure the infection. However, the lack of suitable model systems in which to evaluate new immunotherapeutic approaches represents a critical barrier in the field. The overall goal of this proposal is to develop a new mouse model for HBV that unites the physiological relevancy of the human immune system with the convenience and reproducibility of genetically defined transgenic mice. Our general approach will be to combine well-characterized mouse models of HBV replication with a new strain of "humanized" mice whose immune systems can be efficiently reconstituted with T cells from HBV-infected patients. We will then test the hypothesis that engraftment of human immune cells in these mice will lead to an HBV-specific immune response in the liver, and that this response will reflect the disease status of the human donor. To evaluate our hypothesis, we will carry out two specific aims. First we will introduce HBV replication into the liver of a mouse strain that contains a number of knock-in gene-humanizations to improve the engraftment, differentiation, and maintenance of human hematopoietic populations in the animals. Second, we will engraft these mice with PBMC from acute-resolved and chronic HBV patients, and characterize how these immune cells traffic to the liver and respond to hepatocytes that produce HBV antigens. The intent of developing this model system is to provide new means for studying the human HBV immune responses in vivo. This will fill a critical unmet need, and we anticipate that this system will have wide application for both basic and translational HBV research to understand T cell functionality in chronic HBV infection, evaluate novel immunotherapeutic approaches, and identify determinants of HBV immunopathogenesis. Such analyses could have a substantial impact on the study and treatment of chronic liver infections in humans.