T-cell mediated adaptive immunity to pathogens, tumor- and self-antigens in autoimmunity, is dependent on the specific recognition by a unique TCR of the MHC-peptide (pMHC) antigen on the target cell. The identification of specific T cells, their functional potential and clonotypic TCR sequence is essential to understand the complexity of an immune response to be able to manipulate it for therapeutic benefit.
We have developed an MHC multimer technology, the dCODE Dextramer reagents, that are comprised of a dextran backbone displaying multiple pMHCs and a unique DNA barcode coding for the displayed pMHC specificity. The dCode Dextramer is compatible with 10x Genomics Chromium platform for single cell analysis.
In this study we have exploited how a panel of MHC II dCODE Dextramer reagents can be used for the characterization of antigen-specificity, TCR clonotype and gene expression of single CD4+ T cells from human peripheral blood.
Initially, the integrity of each dCODE Dextramer was demonstrated by specific labelling of CD4+ T-cells in flowcytometry. Subsequently, using the MHC II dCODE Dextramer panel we were able to identify and correlate antigen specific CD4+ T cells, with their unique TCR clonotypes and phenotypic gene expression profiles.
In conclusion the MHC II dCODE Dextramer can reveal 1) antigen specificity, 2) TCR clonotype and 3) functional gene expression profile of single CD4+ T cells. This allows a new understanding of cellular immunology that can progress immunological research and immunotherapeutic development.