Vav1-cre;Mof^f/fhematopoietic E14.5 fetal liver cells are functionally impaired. (A) Day 10 of CFU assay of fresh FL cells derived from E14.5 Vav1-cre;Mof^f/f, Vav1-cre;Mof^f/+, and Mof^f/f embryos. Bar graph indicates mean number of colonies per dish after 10 days. In all, 20 000 cells were plated per dish. Data are representative of 3 individual experiments with multiple embryos per experiment. (B) Shown is the mean percentage of the various colony types relative to all colonies counted per dish per genotype. (C) Schematic for transplant experiment with FL cells derived from E14.5 Vav1-cre;Mof^f/f, Vav1-cre;Mof^f/+, and Mof^f/f embryos. B6.SJL recipient mice were injected with FL cells shortly after lethal irradiation (2 × 5 Gy). The experiment was repeated 2 times with multiple donor embryos per genotype per experiment. (D) Survival curve of recipient mice. All mice were euthanized 16 weeks posttransplant. Vav1-cre;Mof^f/f, n = 6; Vav1-cre;Mof^f/+, n = 6; Mof^f/f, n = 7. (E) Percent of CD45.2 live cells in PB over the time-course of the transplant experiments. (F) Schematic for transplant experiment with FL cells derived from E14.5 Vav1-cre;Mof^f/f, Vav1-cre;Mof^f/+, and Mof^f/f embryos and 250 000 whole BM helper cells. B6.SJL recipient mice were injected with cells shortly after lethal irradiation. The experiment was repeated 2 times with multiple donor embryos per genotype per experiment. (G) Percent of CD45.2 live cells in the PB over the time-course of the transplant experiments. Vav1-cre;Mof^f/f, n = 6; Vav1-cre;Mof^f/+, n = 5; Mof^f/f, n = 5. (H) Percent of CD45.2 live cells in BM of recipient mice at week 16. (I) PCR analysis illustrating Mof excision in CD45.2⁺ BM cells at time of euthanasia. A representative image is shown. Error bars represent SD of mean. Significance is shown for comparing Vav1-cre;Mof^f/f and Vav1-cre;Mof^f/+ to Mof^f/f. **P < .01.