Hematopoietic progenitor cell egress is regulated by the chemotactic lipid S1P. (A-E) Mice were injected with PBS or administered with glucose in the drinking water (control), injected with FTY720 (single intraperitoneal injection 1.5 hours and 24 hours before sacrifice) or administered with DOP (together with glucose for 3 days in the drinking water). The numbers of WBC (A), CFU-C (B) and primitive SKL cells (C) per milliliter of blood were analyzed. BM SKL numbers per 1 × 106 total BM cells (D) are shown. SDF-1 ELISA levels in the plasma (E) are determined. Indicated values are presented as mean ± SE in 3 independent experiments, a total of 6 mice in each group (*P < .05, **P < .01).