sCFU-E cells expand in erythropoietic stress. (A) Flow cytometric gating strategy. (B) Percentages of sCFU-E cells increase in the bone marrow and spleen of phlebotomized (Phleb.) mice 2 days after phlebotomy. (C) RBC counts on indicated day after phlebotomy. (D) Representative flow cytometry plots of temporal sCFU-E cell increases in the bone marrow (BM) and spleen (SP) of phlebotomized mice. (E) Quantification of percentage changes of sCFU-E cells in (D). (F) Quantification of BFU-E, sCFU-E, CFU-E, and Ter119⁺ cell percentages in phlebotomized mice at indicated times. (G) Total numbers of BFU-E, sCFU-E, CFU-E, and Ter119⁺ cells in phlebotomized mice at indicated times. Data represent the mean ± SD. ∗P < .05; ∗∗P < .01, 1-way ANOVA.