Because whole tumor cells are a good source of TAAs and can induce simultaneous CD8+ cytotoxic T lymphocytes (CTLs) and CD4+ T helper cell activation (7), we further unsupervised clustering CD8+ T cells and defined two sub-clusters: CD8+ TCM, which highly expressed markers of memory-like phenotype (SELL, LEF1, CCR7, IL7R, TCF7, CD44, CXCR4), and CD8+ TEX, which highly expressed the known exhausted markers (TIGIT, PDCD1, CTLA4, LAG3, HAVCR2, BATF) (24) (Figures 3A, B). The gene discussed is PDCD1; the disease is neoplasm.