Establishment of cell culture model and humanized mouse model of chronic hepatitis B virus infection

ABSTRACT The absence of a hepatitis B virus (HBV) infection system has constrained the study of the viral life cycle and the development of antiviral drugs. We previously established a hepatocellular carcinoma cell line, HLCZ01, that can support the entire life cycle of HBV. To further optimize the model, we compared the kinetic process of HBV infection in HLCZ01 and HepG2-NTCP cells and found that HLCZ01 cells were more conducive to mimic the long-term stable infection of HBV in the natural state. By comparing the composition of the progeny virus and the differences in gene expression profiles between these two types of cells, we were able to explore the factors affecting the efficiency of virus infection. We built an experimental platform for human liver chimeric mice and established a standard surgical procedure. By transplanting HBV-infected HLCZ01 cells into mouse liver, which can be used instead of primary human hepatocytes to establish chimeric mice, this animal model can continuously produce viral particles. The establishment of these two models will facilitate the exploration of the mechanism of persistent HBV infection, the understanding of host‒virus interactions, and the determination of new targets for chronic hepatitis B therapy. IMPORTANCE Approximately 257 million people worldwide have been infected with hepatitis B virus (HBV), and HBV infection can cause chronic hepatitis, cirrhosis, and even liver cancer. The lack of suitable and effective infection models has greatly limited research in HBV-related fields for a long time, and it is still not possible to discover a method to completely and effectively remove the HBV genome. We have constructed a hepatocellular carcinoma cell line, HLCZ01, that can support the complete life cycle of HBV. This model can mimic the long-term stable infection of HBV in the natural state and can replace primary human hepatocytes for the development of human liver chimeric mice. This model will be a powerful tool for research in the field of HBV.