Arlauckas et al. recently showed in a mouse model that anti-PD-1 antibody could be transferred from PD-1+ T cells to macrophages via FcγR-dependent manner [45], supporting our findings that tumor-associated macrophages and FcγRI can negatively impact on anti-PD-1 antibody-mediated anti-tumor efficacy. Here, PDCD1 is linked to neoplasm.