T cell responses play an important role in the outcome of HBV and HCV infection, e.g. viral elimination versus persistence. However, multiple mechanisms can lead to the failure of the virus-specific T cell response.
These mechanisms include primary T cell failure, T cell exhaustion, the emergence of viral escape mutants, as well as T cell dysfunction. Furthermore, genetic factors such as the individual HLA allele background play an important role in the outcome of infection. Once viral persistence has been established, HBV or HCV infection can progress to liver fibrosis and cirrhosis with an enhanced risk for HCC. Tumor-specific T cells (e.g. AFP-specific T cells) are thought to contribute to cancer control.
The focus of our group is the identification and characterization of virus-specific CD4+ and CD8+ T cell responses during acute and chronic HBV and HCV infection with a special focus on intrahepatic T cell responses as well as the mechanisms of viral persistence (e.g., viral escape, T cell dysfunction, action of regulatory T cells, role of HLA alleles). Furthermore, we study AFP-specific T cell responses in patients with HCC.