Tetherin has negligible activity in restricting hepatitis C virus in hepatocytes

We investigated the ability of tetherin, a recently identified antiviral factor, in restricting hepatitis C virus (HCV) in the Japanese fulminant hepatitis-1 (JFH-1) infectious cell culture system. Human hepatocytes (Huh7, Huh7.5.1) expressedlow levels of endogenous tetherin, which could be induced by IFN-α. However, tetherin contributes little to IFN-α-mediated anti-HCV JFH-1 activity. Although tetherin could inhibit Vpu-deleted HIV-1 release, it had negligible activity in restricting HCV JFH-1 release from hepatocytes, which was evidenced by unaffected levels of intracellular/extracellular HCV RNA and infectious virus. The failure of tetherin's anti-HCV activity could not be related to the counteraction of HCV, as HCV infection of hepatocytes affected neither tetherin expression nor anti-HIV function of tetherin. These observations imply that tetherin has negligible activity in the restriction of HCV JFH-1 in human hepatocytes.