Specific deletion of PIT1 at the adult stage results in hematopoietic defect. (A) Quantitative analysis of PIT1 mRNA expression in Mx1-Cre;PIT1^lox/lox BM mice 6 months after pIpC treatment. (B) Six-month-old PIT1^lox/lox mice spleen (top) and PIT1^neo/neo mice spleen (bottom). (C) Spleen section stained with H&E at 2.5 and 40× magnification. (D) In vitro differentiation of adult hematopoietic spleen cells from Mx1-Cre;PIT1^lox/lox. The numbers of CFU-GM and CFU-E per 10⁵ nucleated spleen cells are indicated. (E) Representative flow cytometric analysis of PIT1^lox/lox and Mx1-Cre;PIT1^lox/lox adult spleen. Percentages of labeled cells were calculated by taking into account the background labeling (baseline define by omitting Ab). (F) Measurement of 2,3-DPG Mx1-Cre-PIT1^lox/lox mice blood. Data indicate the means ± SEM of at least 5 animals per condition. Significant differences from PIT1^lox/lox mice (black bar) are indicated. *P < .05; **P < .01; ***P < .001.