Latent hepatitis B virus (HBV) infection and HBV DNA integration is associated with further transformation of hepatoma cells in vitro.

Hepatitis B virus (HBV) is the major cause of chronic liver disease and hepatocellular carcinoma in the world, with more than 400 million people infected worldwide. To date, there is no reliable model for the study of the many aspects of HBV infection, despite the use of the chimpanzee. Although several alternative methods have been previously developed for the in vitro study of HBV infection, there is still an urgent need for new in vitro infection models, including for the ability of HBV to integrate into the host cell genome. Here we describe a process to improve infection of the human hepatoma cell lines HepG2 and HuH-7 in vitro with HBV originating from human blood. As shown previously for infection of hepatocytes with hepatitis C virus (HCV), the removal of the cell-bound lipoproteins prior to the addition of the viral inoculum to the cells could also be critical for the uptake of HBV via lipoprotein (LDL)-related receptors. Induction by insulin and dexamethasone led to an increase of HBsAg expression at the cell surface in association with the integration of the viral DNA into the host genome and HBx RNA detection. This integration process was also shown to be associated with cytopathic changes and further phenotypic transformations of the cells.