Methods for Detection of Antigen-Specific T Cells by Enzyme-Linked Immunospot Assay
The enzyme-linked immunospot (ELISPOT) assay to detect T cell responses was developed based on the initial technique reported by Czerkinsky et al. in 1983 as an alternative to the plaque-forming assay for the detection of antibody-secreting cells. In an effort to increase the sensitivity of ELISPOT, several groups have developed modifications of the standard protocol involving the addition of exogenous cytokines, costimulatory antibodies, or antigen-presenting cells. The assay-related positive control will provide information on the assay performance over time and can be informative regarding the standard deviations and coefficient of variation of the results. In general, the steps related to the quality control of the assay should be developed during the qualification process and included in the related standard operating procedure documents. When properly performed under good clinical laboratory practice-compliant conditions, the ELISPOT assay can be a valuable tool for T cell characterization.