Abstract: Methods and compositions for the discovery and production of antibodies that can be used to identify and/or isolate hematopoietic stem cells (HSCs), for example, HSCs with high reconstitution potential. Methods and compositions are further provided for the treatment of patients with hematologic or genetic disorders, patients with cardiovascular disorders, patients recovering from wounds, or patients recovering from chemotherapy or radiation exposure using HSCs or genetically modified HSCs, for example, HSCs and/or genetically modified HSCs with high reconstitution potential.