Abstract: Maturation signals provided via cyclic adenosine monophosphate (cAMP)/Exchange proteins activated by cAMP (Epac) signaling during in vitro generation of blood cells from reprogrammed cells or pluripotent stem cells achieve superior function of hematopoietic cells differentiated from stem cells. The cAMP/Epac signaling enables an increased efficiency of production of precursor to blood and to blood cells. These generated blood cells can be utilized for therapeutics, treatments, disease prevention, drug discovery, personalized medicine, regenerative medicine, cell and tissue generation, universal donor banks and related methods and compositions.