CD274 and neoplasm: Interestingly, A223 tumors were PD-L1+ (13.09% of tumor cells); however, the PD-L1+ cells were primarily tdTomato+ recipient cells (85.88%), and the majority of those cells (87.46%) were CD11b+ CD11c− myeloid cells (Fig. 2b, c, gating strategy in Supplementary Fig. 4).