Targeting virus-specific CD8+ T cells for treatment of chronic viral hepatitis: from bench to bedside.

Chronic viral hepatitis is a global health issue with an urgent need for new therapeutic approaches. Cytotoxic T killer cells (virus-specific CD8+ T cells) are key players in mediating control of viral hepatitis, and chronic infection is associated with dysfunction of these cells. Therefore, reconstitution of virus-specific CD8+ T cells by immunotherapy is an interesting therapeutic approach for chronic viral hepatitis. In this review, we will compare data on different mechanisms contributing to CD8+ T cell dysfunction in chronic hepatitis B, C, D, and E virus infection, respectively. Furthermore, preclinical and clinical studies for the individual hepatitis viruses will be discussed.