CD47 and neoplasm: Additionally, CD47 binds to the signal regulatory protein α (SIRPα) on the surface of macrophages, forming a “don't eat me” signal that helps tumor cells with high CD47 expression evade phagocytosis by immune cells.[5] Therefore, combining TAMs reprogramming with immune checkpoint blockade can more effectively enhance the phagocytic capacity of TAMs, breaking their immunosuppressive state.