Choong Tat Keng1, Ching Wooen Sze2, Dahai Zheng1, Zhiqiang Zheng1, Kylie Su Mei Yong1, Shu Qi Tan3, Jessica Jie Ying Ong1, Sue Yee Tan1, Eva Loh4, Megha Haridas Upadya2, Chik Hong Kuick4, Hak Hotta5, Seng Gee Lim6,7, Thiam Chye Tan3,8, Kenneth T E Chang4,8, Wanjin Hong1, Jianzhu Chen9,10, Yee-Joo Tan1,2, Qingfeng Chen1,2,9
1 Institute of Molecular and Cell Biology, Singapore, Singapore
2 Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
3 Department of Obstetrics & Gynaecology, KK Women's and Children's Hospital, Singapore, Singapore
4 Department of Pathology and Laboratory Medicine, KK Women's and Children's Hospital, Singapore, Singapore
5 Division of Microbiology, Kobe University Graduate School of Medicine, Hyogo, Japan
6 Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
7 Department of Gastroenterology and Hepatology, National University Health System, Singapore, Singapore
8 Duke-NUS Graduate Medical School, Singapore, Singapore
9 Interdisciplinary Research Group in Infectious Diseases, Singapore-Massachusetts Institute of Technology Alliance for Research and Technology, Singapore, Singapore
10 The Koch Institute for Integrative Cancer Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
Published online in Gut, on 6th July, 2015.
Conclusions The HIL mouse provides a model for the understanding of HCV-specific human immune responses and HCV-associated disease pathologies. It could also serve as a platform for antifibrosis and immune-modulatory drug testing.
Objective HCV infection affects millions of people worldwide, and many patients develop chronic infection leading to liver cancers. For decades, the lack of a small animal model that can recapitulate HCV infection, its immunopathogenesis and disease progression has impeded the development of an effective vaccine and therapeutics. We aim to provide a humanised mouse model for the understanding of HCV-specific human immune responses and HCV-associated disease pathologies.
Design Recently, we have established human liver cells with a matched human immune system in NOD-scid Il2rg−/− (NSG) mice (HIL mice). These mice are infected with HCV by intravenous injection, and the pathologies are investigated.
Results In this study, we demonstrate that HIL mouse is capable of supporting HCV infection and can present some of the clinical symptoms found in HCV-infected patients including hepatitis, robust virus-specific human immune cell and cytokine responses as well as liver fibrosis and cirrhosis. Similar to results obtained from the analysis of patient samples, the human immune cells, particularly T cells and macrophages, play critical roles during the HCV-associated liver disease development in the HIL mice. Furthermore, our model is demonstrated to be able to reproduce the therapeutic effects of human interferon alpha 2a antiviral treatment.
Figure Legend: HCV can infect HIL mice leading to liver inflammation and liver injury. (A and B) Ten-week-old HIL mice were mock-infected or HCV-infected. (A) Human epidermal growth factor receptor+ (hEGFR+) cells were purified from mouse livers at 2 and 5 weeks post-infection and analysed for HCV RNA by RT-PCR (n≥5 mice per group). In one group of mice, HCV infection was performed with T cell depletion and analysis was performed at 5 weeks post-infection (indicated by #). Values from each mouse are plotted as symbols, and the average values for each group are plotted as solid lines. (B) Staining of dsRNA (in red) and CK18 (in green) in the hEGFR+ cells purified from HIL mice at 2 and 5 weeks post-infection. (C) Livers were harvested and paraffin sections were prepared 5 weeks post-HCV infection (n=5 mice per group). Representative stains for DAPI (blue), anti-HCV core (green) and antihuman albumin (hALB) (red) are shown. (D and E) Ten-week-old HIL mice were infected with HCV or mock-infected for 0, 1, 3, 5 and 9 weeks (n=5 mice per group). Livers and sera were harvested for histology and alanine aminotransferase (ALT) assay. (D) Representative liver H&E stains of mock-infected and HCV-infected mice from different time points are shown. (E) Serum ALT levels in HIL mice that were mock-infected or HCV-infected from different time points are represented. Data represent mean±SEM.
For more information on Qingfeng CHEN's laboratory, please click here.