CD8A and neoplasm: CD8 T-cell cytotoxic activity induces tumor-cell death and promotes the priming of tumor-specific T cells,31 32 with this effect being partially dependent on CD8 T-cell Perf-mediated killing of tumor cells.32 In order to determine if Perf in CART cells was required for the antitumor efficacy of the CART/STING-L combination, we generated Perf-deficient CART cells and compared them with WT CART cells.