“…Roles for B cells and antibodies, T cells, and control of intramacrophage bacterial growth have all been identified as important, but the exact balance of these for vaccine mediated protection against subsequent infection remains unclear [ 23 , 24 ]. Notably, a very recent study examining human immune correlates to LVS vaccination showed that the cytokines IFNγ, TNF, IL-17 and IL-2 produced by T cells were most correlated with monocyte derived macrophage killing of the highly virulent SchuS4 strain in vitro [ 25 ]. Additionally, this study showed a range of both CD4 and CD8 memory T cell responses that lasted over a year after vaccination.…”