The development of the fluorescently labeled tetrameric MHC-peptide complex has enabled the direct visualization, quantification and phenotypic characterization of antigen-specific T cells using flow cytometry and has transformed our understanding of cellular immune responses. The combination of this technology with functional assays provides many new insights into these cells, allowing investigation into their lifecycle, manner of death and effector function. Understanding how the antigen-specific cells develop and function in different circumstances and with different pathogens will be key to understanding natural host defense, as well as vaccine design and assessment.
Recently, Stanford University School of Medicine has presented MHC-peptides tetrameric complexes (MHC tetramers) in the detection of antigen-specific T cells, thus provided an efficient method to visualize, quantify, phenotype and sort antigen-specific cytotoxic T lymphocytes (CTLs) directly from a wide range of biological samples and have now become standard reagents in laboratories around the world.
