PHD inhibitors stabilize HIF-1α in vivo. (A) Mice were injected with a single dose of 20 mg/kg of FG-4497, 400 mg/kg of DMOG, or saline and BM cells were harvested at 2, 6, and 12 hours after injection. Cell lysates from 8 × 10⁴ BM cells were run on a SDS-PAGE gel for each time point. After electro-transfer, membrane was blotted with rabbit anti–HIF-1α and anti–β-actin antibodies. (B-C) Mice were injected twice with saline or 20 mg/kg of FG-4497 at 12 and 2 hours prior to harvesting. (B) Typical plots showing the gating strategy to measure intracellular HIF-1α in BM cells. Intracellular HIF-1α protein in HSPC populations was measured by flow cytometry (C). Data are shown as means ± SD (4 mice per group) of the mean fluorescence intensities of HIF-1α fluorescence profiles in total BM leukocytes, LKS⁺ CD48⁺ lineage-restricted HPCs, LKS⁺CD48⁺CD150⁻ multipotent progenitors, and LKS⁺CD48⁻CD150⁺ HSCs. Significance levels were calculated using a t test.