Transplantation studies. EPAS1/HIF-2α null donors. (A) CFU-S frequency 8 days after transplantation in irradiated recipient mice receiving bone marrow from either a 1-month-old male EPAS1/HIF-2α null (▪) or wild-type littermate (□) mouse. (B-C) Spun hematocrits (B) or complete blood cell count results (C) for leukocytes (WBC), erythrocytes (RBC), and platelets (PLT) 30 days after transplantation in irradiated recipient mice receiving bone marrow from either an EPAS1/HIF-2α null (▪) or wild-type littermate (□) mouse. No significant differences were noted for CFU-Ss, spun hematocrits, or complete blood cell counts. Error bars indicate SEM.