CD47 and acute myeloid leukemia: It provides an anti-phagocytic signal in healthy cells but was discovered as an adverse prognostic factor in AML as it is overexpressed on leukemic stem cells compared to non-leukemic stem cells; preclinical murine models demonstrated that blockade of CD47 with monoclonal antibodies could enable phagocytosis of leukemic stem cells and prevent in vivo engraftment [164, 165].