CD274 and neoplasm: The fluorescent immunohistochemistry (IF-IHC) staining also revealed that cisplatin-combined α-IL-33 or α-ST2L treatment suppressed the amount of tumor-infiltrating M2 macrophages and Tregs and reduced expression of PD-L1 immunosuppressive molecule, while increasing tumor-infiltrating CD8 T cells in LLC tumors (Fig. 5H, I and Supplementary Fig. S5H, I).