Gene expression signatures in activated CD4 T cells to predict_vaccine responses

To decipher the molecular mechanisms underlying_variable_vaccine responses, T- and B-cell responses to_vaccination with a life zoster_vaccine were examined in individuals of different ages. Diminished generation of long-lived memory T cells in older individuals was mainly caused by increased T cell loss after the peak response while the expansion of antigen-specific T cells was not affected by age. Gene expression in activated CD4 T cells co-expressing HLA-DR and CD38 at the time of the peak response identified gene modules related to cell cycle regulation and DNA repair that correlated with the contraction phase of the T cell response and consequently the generation of long-lived memory cells. We immunized 17 individuals aged 50 to 75 years with the life zoster vaccine Zostava. We measured VZV-specific T cell frequencies by IFN-γ–specific ELISpot, and VZV-specific antibody titers by ELISA. Gene expression in purified CD4 T cells co-expressing CD38 and HLA-DR were measured on day 0, day8 and day 14 after varicella zoster vaccination (VZV) in 17 individuals. Gene expression was correlated with vaccination-induced changes in the frequencies of VZV-specific T cells