Longevity of T-cell memory following acute viral infection

Investigation of T-cell-mediated immunity following acute viral infection represents an area of research with broad implications for both fundamental immunology research as well as vaccine development. Here, we review techniques that are used to assess T-cell memory including limiting dilution analysis, enzyme-linked immunospot (ELISPOT) assays, intracellular cytokine staining (ICCS) and peptide-MHC Class I tetramer staining. The durability of T-cell memory is explored in the context of several acute viral infections including vaccinia virus (VV), measles virus (MV) and yellow fever virus (YFV). Following acute infection, different virus-specific T-cell subpopulations exhibit distinct cytokine profiles and these profiles change over the course of infection. Differential regulation of the cytotoxic proteins, granzyme A, granzyme B and perforin are also observed in virus-specific T cells following infection. As a result of this work, we have gained a broader understanding of the kinetics and magnitude of antiviral T-cell immunity as well as new insight into the patterns of immunodominance and differential regulation of cytokines and cytotoxicity-associated molecules. This information may eventually lead to the generation of more effective vaccines that elicit T-cell memory with the optimal combination of functional characteristics required for providing protective immunity against infectious disease.