Solute Carrier NTCP Regulates Innate Antiviral Immune Responses Targeting Hepatitis C Virus Infection of Hepatocytes

Abstract

Summary: Chronic hepatitis B, C, and D virus (HBV, HCV, and HDV) infections are the leading causes of liver disease and cancer worldwide. Recently, the solute carrier and sodium taurocholate co-transporter NTCP has been identified as a receptor for HBV and HDV. Here, we uncover NTCP as a host factor regulating HCV infection. Using gain- and loss-of-function studies, we show that NTCP mediates HCV infection of hepatocytes and is relevant for cell-to-cell transmission. NTCP regulates HCV infection by augmenting the bile-acid-mediated repression of interferon-stimulated genes (ISGs), including IFITM3. In conclusion, our results uncover NTCP as a mediator of innate antiviral immune responses in the liver, and they establish a role for NTCP in the infection process of multiple viruses via distinct mechanisms. Collectively, our findings suggest a role for solute carriers in the regulation of innate antiviral responses, and they have potential implications for virus-host interactions and antiviral therapies. : Verrier et al. identify the sodium taurocholate co-transporter NTCP as a host factor regulating HCV infection. NTCP-mediated bile acid transport regulates innate responses targeting HCV infection. NTCP is a mediator of innate immunity and plays a role in the infection of multiple hepatotropic viruses. Keywords: NTCP, hepatitis C virus, solute carrier, innate immune responses, viral entry, host factor, signaling, antiviral therapy, hepatitis B virus, hepatitis D virus