CD274 and neoplasm: The highest percentage of PD-L1+ and PD-L2+ macrophages was detected in the tumor tissue, and it was significantly higher (p < 0.0001) than in PB (median 40.43% vs. 10.41% for PD-L1+ cells and 7.38% vs. 1.43% for PD-L2+ cells) (Figures 5(a) and 5(b)).