HSPC frequency is increased in FL cells lacking hypoxic Vegfa induction. (A) FL cellularity of Vegfa^δ/δ or WT mice. Results shown are combined data from 5 independent experiments. Bars represent mean ± SD, **P = .0042 Mann-Whitney test. (B) Total CFU frequency was measured by plating 2 × 10⁴ FL cells/mL in methylcellulose followed by incubation in normoxia for 7 days. Results shown are data combined from 4 independent experiments. (C) The frequency of LSK cells in FL was measured by FACS analysis. Representative FACS plots of lineage⁻ gated cells. (D) Percentage LSK cells in FL. **P = .0059, t test. (E) Total number of LSK cells per FL. (F) The frequency of LSK CD150⁺ cells in FL was measured by FACS analysis. Representative FACS plots of LSK gated cells are shown. (G) Percentage LSK CD150⁺ cells in FL. *P = .0187, t test. (H) Total number of LSK CD150⁺ cells per FL. Results shown in panels C-H are data combined from 4 independent experiments. Bars represent mean ± SD, n = 8-9 mice per genotype.