Antiviral activity and host gene induction by tamarin and marmoset interferon-α and interferon-γ in the GBV-B primary hepatocyte culture model

GBV-B induces hepatitis in tamarins and marmosets and is a surrogate model for HCV infections. Here, we cloned and characterized the antiviral activity of tamarin and marmoset interferon (IFN)α and IFNγ. Potent antiviral activity was observed for tamarin and marmoset IFNα in primary hepatocyte cultures infected with GBV-B. The antiviral activity was greater in cultures exposed to IFNα prior to GBV-B infection, suggesting that either GBV-B was capable of inhibition of the antiviral activity of exogenous IFNα or that the preexisting endogenous IFN response to the virus reduced efficacy to exogenous IFNα. IFNγ also exhibited antiviral activity in GBV-B infected hepatocytes. The transcriptional response to IFNα in marmoset hepatocytes was characterized using human genome microarrays. Since the GBV-B hepatocyte culture model possesses a functional innate immune response, it will provide opportunities to explore the nature of the antiviral response to a virus closely related to HCV.