Long-term engraftment of mobilized HSPC in vivo. (A) Dose-dependent effects of AM1241 in HSPC mobilization. Mice were injected intraperitoneally with AM1241 at the indicated doses once daily for 4 consecutive days. Twenty-four hours after the last injection, mice were killed, peripheral blood was collected, and MNCs were isolated and seeded (1 × 105 cells). Ten days after seeding, colonies were counted. *P < .05 vs control (n = 9). (B) Schematic representation of the transplantation experiment. B6-Ly5.2 mice were treated with AM1241, G-CSF, or vehicle control (intraperitoneal injection). A total of 8 × 105 mobilized peripheral blood MNCs were mixed with 2 × 105 BM cells from B6-Ly5.1 mice and transplanted into lethally irradiated Ly5.1 mice. (C) Triple-lineage reconstitution by mobilized HSPCs in vivo 20 weeks after transplantation. Contribution of the vehicle-, AM1241-, and G-CSF-mobilized cells (Ly5.2+) into the distinct lineages was determined by B220-allophycocyanin-Cy7, CD4/CD8-fluorescein isothiocyanate, and Gr1/Mac1-PE labeling and flow cytometric analysis. The percentages of B cells, T cells, and myeloid cells are in relation to the total MNCs in the recipient mice. The figure represents one representative animal in each group (n = 9 per group; supplemental Table 3).
