CD47 and acute myeloid leukemia: CD47/SIRPa signaling (“don’t eat me” signal) is one of the pathways harnessed by tumor cells to escape from phagocytosis by immune cells.49, 50, 51 CD47 is a checkpoint receptor overexpressed in different hematological (e.g., acute myelogenous leukemia [AML] and non-Hodgkin lymphoma [NHL]) and solid malignancies (e.g., colon, bladder, and brain).49, 50 To interfere with the CD47/SIRPa interaction, different therapeutic agents are developed, including anti-CD47 mAbs, SIRPa blocking agents, SIRPa-Fc fusion proteins, and bsAbs targeting CD47 and the tumor target.