Figure 1. Recurrent neoantigen discovery pipeline.

Data-driven analysis of cancer patient cohorts was used to select high-recurrence RAS.Q61/HLA allele combinations that were predicted to yield neoantigens, with HLA-A*01:01/RAS.Q61 heading the list. Robust neoantigen presentation was corroborated and quantified via HLA peptidomics using a panel of tumor samples with endogenous expression. Specific reactivity was identified within TILs from 2 unrelated patients, thus validating the immunogenicity of the neoantigen. Tetramer-specific cells were TCR- and RNA-sequenced at the single-cell level, allowing transcriptional profiling of neoantigen-specific clones. A repertoire of sensitive and specific TCRs were characterized, with striking intra- and interpatient TCR sequence similarity between clones. Parts of Figure 1 were created using BioRender.com.