Ezh2 is dispensable for fetal HSC. (A) Representative image of wild-type (WT; n = 21; 5 independent experiments), Tie2-Ezh2-KO (n = 4; 2 independent experiments), and Vav-Ezh2-KO (n = 7; 3 independent experiments) embryos at E13.5. Scale bars, 1 mm. (B) Representative FACS histogram plots showing the recombination efficiency of Tie2-Cre (n = 6; 1 experiment) and Vav-iCre (n = 3; 1 experiment) in E12.5 FL LSK cells using Rosa26-LSL-tdTomato reporter. (C) Absolute numbers of Tie2-Ezh2-WT (n = 37), Tie2-Ezh2-KO (n = 9), Vav-Ezh2-WT (n = 16), and Vav-Ezh2-KO (n = 7) total mononuclear cells, LSK, multipotent progenitor (MPP) (LSKCD150⁻CD48⁺), and HSC (LSKCD150⁺CD48⁻) per FL at E12.5. Data pooled from 5 (Tie2-Cre) and 4 (Vav-iCre) independent experiments. (D) Absolute numbers of Vav-Ezh2-WT (E12.5, n = 16; E18.5, n = 13) and Vav-Ezh2-KO (E12.5 and E18.5, n = 7) LSK cells and HSCs per FL at E12.5 (4 independent experiments) and E18.5 (3 independent experiments). (E) Absolute numbers of Vav-Ezh2-WT (n = 7) and Vav-Ezh2-KO (n = 4) LSK cells and HSC per femur and tibia at E18.5 (2 independent experiments). (F) Peripheral myeloid cell (Mac1⁺) reconstitution kinetics in CD45.1 mice transplanted with 500 000 CD45.2 Tie2-Ezh2-WT (n = 5), Vav-Ezh2-WT (n = 4), Tie2-Ezh2-KO (n = 10) or Vav-Ezh2-KO (n = 6) total E12.5 FL cells; Vav-Ezh2-WT (n = 11) or Vav-Ezh2-KO (n = 13) E18.5 FL cells, in all cases together with 1 000 000 CD45.1 competitor BM cells. Data are pooled from 2 (E12.5) or 3 (E18.5) independent experiments. (G) Contribution of CD45.2 E12.5 FL cells to HSC compartment at 16 weeks following transplantations shown in panel F. Two-tailed Student t tests were used to assess statistical significance. Error bars represent SEM.