From the editor

This 8-part topic review series, “Hepatitis C virus: virology, immunology and pathogenesis”, was designed to provide expert opinion and new insights for the Journal’s readership.

Hepatitis C virus (HCV) is a small single-stranded RNA virus that belongs to the Flaviviridae virus family. More than 120 million people are chronically HCV infected. The factors that determine the outcome and natural course of HCV infection are not completely understood. However, it is generally accepted that next to virological factors innate and adaptive immune responses play an important role in both, control of HCV infection and as disease pathogenesis (Figure 1).

In recent years, significant progress has been made in understanding basic mechanisms of viral replication, innate and adaptive immune responses, such as CD+ and CD8+ T cells as well as neutralizing antibodies, and the possible role of regulatory T cells in orchestrating the adaptive immune response. However, the central question why HCV is able to evade the innate and adaptive immune response and to establish viral persistence in the majority of acutely infected patients is still unknown. In this review series, recent advances in HCV virology and immunology will be highlighted. Clearly, a better understanding of the dynamic host-virus interactions during HCV infection is crucial for the development of new prophylactic and therapeutic vaccines.

4808     Sequence diversity of HCV: Implications for immune control and therapy

            Timm J, Roggendorf M

4818     Interaction of hepatitis C virus with the type I interferon system

            Weber F

4824     Neutralizing antibodies in hepatitis c virus infection

            Zeisel MB, Fafi-Kremer S, Fofana I, Barth H, Stoll-Keller F, Doffoël M, Baumert TF

4831     CD4⁺ T cell r sponses in hepatitis C virus infection

            Semmo N, Klenerman P

4839     Host and viral factors contributing to CD8+ T cell failure in hepatitis C virus infection

            Neumann-Haefelin C, Spangenberg HC, Blum HE, Thimme R

4848     Memory CD8+ T cell differentiation in viral infection: A cell for all seasons

            Radziewicz H, Uebelhoer L, Bengsch B, Grakoui A

4858     Regulatory T cells in viral hepatitis

            Billerbeck E, Böttler T, Thimme R

4865     Hepatitis C virus infection and apoptosis

            Fischer R, Baumert T, Blum HE