EPO and anemia: Since the CD71 marker corresponds to the transferrin receptor 1, which is highly expressed in erythroid cells and also induced by a low iron-body state, we functionally tested the possibility that increased erythropoietin stimulation due to post-irradiation anemia (see Supplementary Figure S2B) or a relative iron deficiency due to intensive erythropoiesis induced CD71 expression in LK cells in regenerating bone marrow.