Variability and gender differences in memory T cell immunity to varicella-zoster virus in healthy adults

Latent varicella zoster virus (VZV) can reactivate and cause zoster, the prevention of which relies upon cellular immunity to VZV. To assess temporal variation of VZV cell-mediated immunity in healthy naturally immune adults, we evaluated VZV-specific responder cell frequencies (RCF) longitudinally over 1 year in each of 25 adults. VZV-specific CD4+ T cells were detected (p < 0.003) and showed minimal variability in RCF. Additional analysis of VZV T cell RCF revealed differences between genders, with only males (p < 0.005) having detectable VZV-specific memory CD4+ T cell responses by this method. Taken together, results suggest that further studies regarding immunization of younger adults and females with the modified, high-potency live attenuated VZV vaccine may be warranted.