An experimental method to delineate responses from pre-existing memory and induced naive T cells in neoepitope candidate screening

Abstract Identifying tumor-specific T cells is critical to the development of T-cell based immunotherapies. As a result, computational tools have been developed predict neoepitopes present within tumor. A common experimental approach used screen neoepitope candidates long-term in vitroexpansion patient peripheral blood mononuclear (PBMC) with candidate peptides-followed by fluorospot detect antigen-specific responses. Although this allows for high-throughput screening candidates, it cannot distinguish between responses from pre-existing memory versus naïve that were primed vitro. We an method fulfill need. designed negative control peptide pool 15-mers no sequential similarity any known antigens. Through use depletion PBMC, we show 12 healthy donors megapool successfully quantifies signal result cell proliferation. Importantly, applied pools cohort donors. found majority neoepitope-specific detected derived induced whereas only maximum 3 had given pool. This work underscores applicability and relevance our characterizing signals provides foundation others study role these various therapeutic outcomes. material upon supported National Science Foundation Graduate Research Fellowship Program under Grant no. 2038238. Any opinions, findings, conclusions or recommendations expressed are those author(s) do not necessarily reflect views Foundation.