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.

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.

Agency
National Institute of Health (NIH)
Institute
National Institute on Alcohol Abuse and Alcoholism (NIAAA)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AA018372-02
Application #
7926901
Study Section
Health Services Research Review Subcommittee (AA)
Program Officer
Wang, Joe
Project Start
2009-09-05
Project End
2011-08-31
Budget Start
2010-09-01
Budget End
2011-08-31
Support Year
2
Fiscal Year
2010
Total Cost
$204,668
Indirect Cost
Name
University of North Carolina Chapel Hill
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
608195277
City
Chapel Hill
State
NC
Country
United States
Zip Code
27599
Washburn, Michael L; Bility, Moses T; Zhang, Liguo et al. (2011) A humanized mouse model to study hepatitis C virus infection, immune response, and liver disease. Gastroenterology 140:1334-44
Cheng, Liang; Wang, Jun; Li, Xiaozhu et al. (2011) Interleukin-6 induces Gr-1+CD11b+ myeloid cells to suppress CD8+ T cell-mediated liver injury in mice. PLoS One 6:e17631