Function is the key: impact of interferon on HCV-specific CD8+ T cells during acute HCV infection

Evaluation of: Badr G, Bedard N, Abdel-Hakeem MS et al: Early interferon therapy for hepatitis C virus infection rescues polyfunctional, long-lived CD8(+) memory T cells. J. Virol. 82(20), 10017-10031 (2008). Treatment of acute HCV infection with IFN-alpha is successful in the vast majority of patients. However, the mechanisms responsible for treatment success have remained unexplained. Specifically, the role of CD8(+) T cells during treatment of acute HCV infection has been controversial since previous studies described a decline in HCV-specific CD8(+) T-cell numbers during acute HCV infection and antiviral treatment irrespective of treatment outcome, Badr et al. demonstrate. that successful viral clearance is associated with a polyfunctional HCV-specific CD8(+) T-cell response. Importantly, IFN-alpha treatment was able to convert previously monofunctional HCV-specific CD8(+) T cells to polyfunctionality, providing a potential explanation for the mechanisms of IFN-alpha-related treatment success during acute HCV infection.