A possible explanation of this phenomenon is suggested by a recent report which revealed that bound anti-PD-1 antibody on T cells can be phagocytosed by PD-1-negative tumor associated macrophages via interaction between the antibody Fc glycan and FcγR on the macrophages, limiting antibody retention in the TME and reducing antibody-induced anti-tumor activity [43]. The gene discussed is FCGR2A; the disease is neoplasm.