Basophils as a major producer of CCL3 in the BM. (A) Femoral and tibial BM-derived HPCs were injected into the right tibial BM cavity of 2 Gy irradiated CD45.1⁺ congenic mice. The c-kit and CCL3 expression on the CD45.2⁺MPO⁺lineage^low cells (R1 and R2) was determined. Percentages of CD45.2⁺MPO⁺ donor-derived myeloid cells and c-kit^lowCCL3⁺ cells are shown in the upper and lower panels, respectively. Representative results from 3 independent experiments are shown. (B) Lineage^lowCD16/32^highc-kit^low cells and lineage^lowCD16/32^highc-kit^high granulocyte macrophage progenitor were isolated from femoral and tibial BMs using a FACSAria Cell Sorter. The obtained cells were stained with Wright and Giemsa staining solution, and representative results from 3 independent experiments are shown with a scale bar of 10 μm. Images were obtained using a BX50 microscope (Olympus) using a ×40 objective lens. CCL3 expression was determined using quantitative real-time polymerase chain reaction analysis. Means ± SD from 3 independent experiments are given. *P < .05; Tukey-Kramer test. (C) CCL3 expression in c-kit^lowCD49b⁺FcεR1⁺ cells (R1 and R2) in the tibial BM of untreated or BM chimeric mice at 8 weeks after transplantation. Rat IgG2a was used as an isotype control. Representative results from 4 independent experiments are shown. (D) CCL3 expression in CD200R3⁺FcεR1⁺CD34⁺FSC^high (BaP1), CD34⁺FSC^low (BaP2), and CD34^lowFSC^low cells (Ba) in the tibial BM and PB. Rat IgG2a was used as an isotype control. Representative results from 3 independent experiments are shown. The mean fluorescence intensity of CCL3 in each population was compared with that in PB Ba. **P < .01; N.S., no significant difference by Dunnett’s test.