Poor mobilization due to microenvironment defect in Vdr^−/− mice. (A) Intact mobilization of Vdr^−/− hematopoietic cells. CD45.1-congenic wild-type mice reconstituted with Vdr^+/+ or Vdr^−/− BM were treated with control PBS/BSA (n = 3) or G-CSF (n = 5–6), and the number of circulating CFU-Cs was assessed. (B) Poor mobilization in Vdr^−/− microenvironment. Vdr^+/+ and Vdr^−/− littermates (high-calcium diet) reconstituted with CD45.1 wild-type (WT) BM were treated with control PBS/BSA or G-CSF, and the number of circulating CFU-Cs was assessed (n = 5-6). ***P < .001.