Presence of naive-like HBV-specific CD8+ T cells in chronically infected patients despite ongoing viral replication

In chronically HBV-infected patients, virus-specific CD8+ T cell responses are rarely detectable ex vivo by conventional tetramer staining. This lack of HBV-specific CD8+ T cell responses may be explained by insufficient priming, T cell exhustion and/or deletion. Here, we set out to address this issue by using new techniques for enumerating virus-specific T cells from human peripheral blood based on the combination of tetramer staining, magnetic-bead enrichment, and multiparametric flow cytometry. Indeed, we were able to detect and characterize CD8+ T cell populations specific for 4 well-described HLA-A0201-rest…