Elvira D'Ippolito, Andreas Carr, Karolin Wagner, Laura Mateyka, Sebastian Scheu, Sebastian Jarosch, Anna Hochholzer, Noomen Hamed, Monika Hammel, Immanuel Andrä, Dirk Busch

Fast identification of clincally relevant T cell receptors for adoptive T cell therapy

T cell engineering with antigen-specific T cell receptors (TCRs) allows the generation of increasingly specific and reliable T cell products for cancer and viral infections. However, the number of TCRs available for clinical use is still limited and often of suboptimal potency. Here, we developed platforms to support a rapid selection of candidate TCRs for therapy from donor material.

The highly diverse antigen-unexperienced TCR repertoire of healthy donors represents a suitable source for identifying tumor-specific TCRs. Rare antigen-specific naïve T cells are enriched from large-size T cell apheresis and single-cell sorted according to pMHC class I multimer staining. During cell sorting, our developed flow cytometry-based functional screening estimates the structural avidity of each individual pMHC multimer-reactive TCR, which correlates with functionality. Altogether, epitope-specific TCRs can be isolated and concurrently ranked according to predicted avidity/functionality. Virus-specific TCRs are, instead, more proficiently isolated from seropositive donors. Considering the higher frequencies of these memory repertoires, we developed a high-throughput, single-cell sequencing-based approach capable of discriminating highly functional and bystander TCRs according to transcriptional shifts in T cell activation genes induced by recent peptide stimulation prior to cell sorting (Wagner et al., Cell Reports 2022; Mateyka et al., Vaccines 2022).