VEGF affects the ability of lineage^– BM progenitor cells to reconstitute irradiated congenic mice. (A) Mice were sublethally irradiated (700 cGy) and then given intravenous injections of 1 × 10⁶ Lin^– BM progenitor cells isolated from mice treated with VEGF (50 ng/h) in vivo for 14 days. Mice were killed 2 to 5 weeks after transplantation and analyzed for the ability of donor BM to reconstitute the host. VEGF infusion results in an accumulation of LT-HSCs (B) and CLPs (C) in the marrow. Representative FACS plots are shown. Graphs represent the percent of LT-HSCs and the percent of CLPs within the total lineage^– BM cell population (mean ± SE; n = 4). *Denotes statistical significance.