Generating reliable custom MHC tetramers with the QuickSwitchTM tetramer platform.

Abstract

Abstract Progress in immunology research depends on the continuous development of novel, more adapted and more user-friendly research tools. In 1996 Altman and Davis invented MHC class I tetramers for directly monitoring MHC/peptide specific CD8+ T cells by flow cytometry. Production of MHC tetramers is long and labor intensive and requires advance knowledge of the peptide sequences to be incorporated in these complexes. The recent Covid-19 pandemic has led to new vaccination strategies, which rely on selecting a collection of immunogenic peptides and generating mRNA constructs that contain these sequences. Peptide selection is primarily based on in silico MHC binding tools, which do not always give reliable results. After this first selection step it is necessary to validate MHC peptide binding. For this purpose, a dual use platform was devised, for both assessing MHC peptide binding in a semi-quantitative manner and for T cell staining. The assay is based on a placeholder peptide (or exiting peptide) that can be exchanged for higher affinity binding peptides. Kits with most frequent MHC class I or II alleles are available. Multiple MHC class I and II tetramers can quickly be generated and used for staining within a couple of days.