CD8A and infection: In chronic HBV infection, ex vivo HBV-specific CD8+ tetramer responses are preferentially identified in HBeAg-negative infection.6 Comparison of immunodominant epitope responses recently revealed phenotypic and functional differences between HBV core18-27-specific and polymerase455-463-specific CD8+ T cells in patients despite similar low viral loads and inflammation.9 We, thus, wondered if these responses differed in their metabolic profile.