Productive HBV infection of well-differentiated, hNTCP-expressing human hepatoma-derived (Huh7) cells

Feasible and effective cell models for hepatitis B virus (HBV) infection are required for investigating the complete lifecycle of this virus, including the early steps of viral entry. Resistance to dimethyl sulfoxide/polyethylene glycol (DMSO/PEG), hNTCP expression, and a differentiated state are the limiting factors for successful HBV infection models. In the present study, we used a hepatoma cell line (Huh7D^hNTCP) to overcome these limiting factors so that it exhibits excellent susceptibility to HBV infection. To achieve this goal, different hepatoma cell lines were tested with 2.5% DMSO / 4% PEG8000, and one resistant cell line (Huh7D) was used to construct a stable hNTCP-expressing cell line (Huh7D^hNTCP) using a recombinant lentivirus system. Then, the morphological characteristics and differentiation molecular markers of Huh7D^hNTCP cells with or without DMSO treatment were characterized. Finally, the susceptibility of Huh7D^hNTCP cells to HBV infection was assessed. Our results showed that Huh7D cells were resistant to 2.5% DMSO / 4% PEG8000, whereas the others were not. Huh7D^hNTCP cells were established to express a high level of hNTCP compared to liver extracts, and Huh7D^hNTCP cells rapidly transformed into a non-dividing, well-differentiated polarized phenotype under DMSO treatment. Huh7D^hNTCP cells fully supported the entire lifecycle of HBV infection. This cell culture system will be useful for the analysis of host-virus interactions, which should facilitate the discovery of antiviral drugs and vaccines.