Flow cytometry of peripheral blood and serum erythropoietin levels. (A) Examples of flow cytometry using CD71 and Ter119 staining of peripheral blood cells. (B) Higher percentage of CD71-positive cells in mutant mice with the most pronounced effect in Klf1wt/ko::Bcl11acko/cko mice. (C) Increased percentage of DRAQ5-positive cells in peripheral blood of mutant mice. (D) Compared with the controls, serum erythropoietin levels were significantly higher in Bcl11acko/cko and Klf1wt/ko::Bcl11acko/cko mice. *P < .05 between mutant and control groups; P < .05 between mutant groups is indicated by a color-matched asterisk. Number of mice is depicted for each experiment separately.