The Elispot Assay: An Easily Transferable Method For Measuring Cellular Responses And Identifying T Cell Epitopes

Characterization of human leukocyte antigen (HLA) class I restricted epitopes derived from viral pathogens is imperative for formulating therapeutic interventions, as well as for vaccine design and monitoring. Sensitive, easy and costeffective assays that measure the frequency of antigenspecific T lymphocytes are crucial for evaluating and improving vaccines and therapies. This paper reviews the ELISPOT technique that allows for quantifying HIVspecific T lymphocytes at the single cell level from peripheral blood by detection of antigeninduced cytokine secretion. The assay can be used successfully to quantify T cell immune responses in humans infected with different pathogens and to assess T cell immunogenicity of vaccines in phase I/II and III clinical trials. This review focuses on the ELISPOT methodology and discusses how it can be standardized and potentially used by multiple international laboratories attached to clinical trial sites.