CD8A and neoplasm: Dextramer staining for CD8+ T cells specific for the KILTFDRL (KL8) neoantigen of MC38 tumor cells, located in the ribosomal protein L18 (36), demonstrated that there was no difference in the frequency of tumor-associated KL8-specific dextramer positive (KL8-dex+) CD8+ T cells in the TME between S47 and P47 mice, but that, unexpectedly, S47 mice harbored significantly elevated frequencies of KL8-dex+ CD8+ T cells in the spleen (Supplementary Fig. S2D).