Ethanol and HBV Infection on HCC Development in A Novel Humanized Mouse Model

描述（由申请方提供）：所有目前的人肝小鼠模型在缺乏功能性免疫系统的情况下仅允许HBV复制。这些模型对于研究宿主免疫应答、它们对HBV发病机制的贡献以及潜在的免疫学途径都是无用的。Rag 2-gC双敲（DKO）小鼠缺乏T/B和NK细胞，并且允许用人造血干细胞（DKO-hu HSC小鼠）发育功能性人免疫系统。正常人T、B和树突细胞存在于淋巴组织如胸腺、脾、外周血（PB）和淋巴结（LN）中。最近，我们还在移植有人肝细胞祖细胞和CD 34 + HSC细胞的DKO小鼠（DKO-hu HSC/Hep小鼠）中共移植人肝细胞和人免疫系统。我建议优化DKO-hu HSC/Hep小鼠，以增加人肝细胞移植的选择性耗尽鼠肝细胞和促进人肝细胞在DKO-hu HSC/Hep小鼠。我们也将在此模型中研究HBV感染、免疫发病机制和肝细胞癌（HCC）的发展。1)优化DKO-hu HSC/Hep模型。a.在体内用优先的鼠肝细胞耗竭改善DKO-hu-HSC/Hep小鼠。我建议使用FKBP二聚化剂AP 20187消耗AFC 8/DKO hu HSC/Hep小鼠（在白蛋白启动子控制下具有FKBP-半胱天冬酶8融合基因的转基因DKO小鼠，14，27）中的鼠肝细胞。B.用抗人c-Met mAb促进人肝细胞生长。为了改善DO-hu-HSC/Hep小鼠中的人肝细胞生长，我们将使用针对人c-Met的激动性抗体（c-Met mAb，小鼠IgG 1），其激活人而非鼠c-Met（46）。2)目的：研究HBV在DKO-hu HSC/Hep小鼠体内的感染及发病机制。a. DKO-hu HSC/Hep模型中的HBV感染和免疫应答。我们将在目前的DKO-hu HSC/Hep模型和SA 1的改进模型中建立HBV感染动力学、免疫应答和发病机制。B.在DKO-hu HSC/Hep模型中观察乙醇对HBV感染、免疫发病及肝癌发生发展的影响。感染HBV的DKO-hu HSC/Hep小鼠将接受急性和慢性饮酒治疗。将研究DKO-hu HSC/Hep小鼠中的HBV复制、免疫应答、发病机制和癌症发展。 公共卫生相关性：该项目的长期目标是开发相关的小鼠模型，以研究HBV感染的免疫发病机制、HCC发展的机制，并模拟基于免疫的治疗。具体而言，我们将开发DKO-hu HSC/Hep模型，用于在不存在或存在酒精诱导的肝损伤的情况下研究HBV感染和免疫发病机制。这些研究将为未来的研究奠定基础，并为控制HBV疾病的新治疗策略提供启示。

DESCRIPTION (provided by applicant): All current mouse models of human liver allow only HBV replication in the absence of a functional immune system. Those models are not useful to studying host immune responses, their contributions to HBV pathogenesis and potential immunotherapeutic approaches. The Rag2-gC double knock (DKO) mouse lacks T/B and NK cells, and allows development of a functional human immune system with human Hematopoietic Stem Cell (DKO-hu HSC mice). Normal human T, B, and dendritic cells are present in lymphoid tissues such as thymus, spleen, peripheral blood (PB) and lymph nodes (LN). Recently, we have also co-engrafted human hepatocytes with human immune system in the DKO mouse transplanted with human hepatocyte progenitor cells and CD34+ HSC cells (DKO-hu HSC/Hep mice). I propose to optimize the DKO-hu HSC/Hep mouse to increase human hepatocyte engraftment by selectively depleting murine hepatocytes and promoting human hepatocytes in the DKO-hu HSC/Hep mouse. We will also study HBV infection, immuno-pathogenesis, and development of hepatocellular carcinoma (HCC) in this model. 1) To optimize the DKO-hu HSC/Hep model. a. Improving DKO-hu-HSC/Hep mice with preferential murine hepatocyte depletion in vivo. I propose to deplete murine hepatocytes in AFC8/DKO hu HSC/Hep mice (transgenic DKO mice with FKBP-caspase8 fusion gene under control of the albumin promoter, 14, 27) with FKBP dimerizer AP20187. b. Boosting human hepatocyte cell growth with anti-human c-Met mAb. To improve human hepatocyte growth in DO-hu-HSC/Hep mice, we will use an agonistic antibody against human c-Met (c-Met mAb, mouse lgG1) that activates human but not murine c-Met(46). 2) To study HBV infection and pathogenesis in DKO-hu HSC/Hep mice. a. HBV infection and immuno-responses in the DKO-hu HSC/Hep model. We will establish HBV infection kinetics, immuno-responses and pathogenesis in the current DKO-hu HSC/Hep model and in the improved models from SA1. b. the effects of ethanol on HBV infection, immuno-pathogenesis and development of hepatocellular carcinoma (HCC) in DKO-hu HSC/Hep model. DKO-hu HSC/Hep mice infected with HBV will be treated with acute and chronic alcohol consumption. HBV replication, immune responses, pathogenesis and cancer development in DKO-hu HSC/Hep mice will be investigated. Public Health Relevance: The long-term goals of this project are to develop a relevant mouse model to investigate the immuno- pathogenesis of HBV infection, the mechanism of HCC development, and to model immune-based therapy. Specifically, we will develop the DKO-hu HSC/Hep model for studying HBV infection and immuno- pathogenesis in the absence or presence of alcohol-induced liver insults. These studies will establish the foundation for future study and shed light on novel therapeutic strategies for controlling HBV diseases.