Figure 3.

Synergistic antitumor effects of blockade of CD47‐signal regulatory protein α (SIRPα) interaction combined with immune checkpoint inhibitors. Blockade of CD47 or SIRPα with corresponding specific Abs promotes the phagocytosis of tumor cells by macrophages or dendritic cells as well as the consequent cross‐priming of tumor‐specific cytotoxic T cells. Activity of cytotoxic T cells is also enhanced by immune checkpoint inhibitors, such as Abs to programmed cell death‐1 (PD‐1) or programmed cell death‐ligand 1 (PD‐L1) that prevent the interaction of these proteins. Blockade of CD47 or SIRPα together with giving immune checkpoint inhibitors may therefore have synergistic antitumor effects