In MM mouse models, depletion of FAPα<sup>+</sup> macrophages significantly boosted the efficacy of anti-PD-1/PD-L1 antibody therapy but not anti-CTLA-4 therapy; this combinatorial strategy also exerted enhanced anti-tumor effects in EL4 lymphoma and CT26 colorectal carcinoma models. Here, CD274 is linked to neoplasm.