CD8A and infection: Nonetheless, vaccine-induced CD8+ T cells are polyfunctional; they are able to produce different effector molecules, such as IFN-γ, TNF-α, and granzyme B; and, like S-specific CD4+ T cells, their distribution among T-cell subsets mirrored the one observed in a natural infection, with a prevalence of TEM and TEMRA cells [138,139,141,147].