Abstract Text: The antigen-specific interaction between the T Cell Receptor (TCR) and cognate peptide MHC (pMHC) complex is at the heart of the successful development of T cell-based therapies. The TCR:pMHC interactions are generally weak, which could be a limitation and hinder the discovery and study of TCRs. The increased avidity of MHC Dextramer reagents has already been shown to enable detection of low affinity antigen-specific CD8, CD4 T cells as well as unconventional T cells. Here, we demonstrate a smooth workflow for discovery of pMHC-specific TCR sequences using single-cell RNA-seq and dCODE Dextramer® reagents, and how TCR functionality can be verified using custom-made TCR monomers and TCR Dextramer® reagents. To date, we have developed TCR Dextramer® reagents recognizing a range of different pMHC specificities, including HLA-E*01:03/peptide, MR1/5-OP-RU and Mamu-A*01/peptide. Finally, we show that TCR Dextramer reagents have been successfully used to specifically detect antigen-presentation on target cells – a useful tool for evaluation of antigen-presentation on variant target cells. This study shows a complete workflow from TCR discovery through TCR validation and final evaluation of target expression using TCR Dextramer®. A set of analytical tools useful in development of TCR immunotherapeutics and cell therapies.
