Percentages of donor-derived c-kit⁺/Lin⁻ cells in MRL/lpr mice treated with 5.5 Gy × 2 + IBM, 5.5 Gy × 2 + PV, or 5.5 Gy × 2 + IV.

(A) A representative dot-plot profile of BMCs (the femur) obtained from MRL/lpr mice 14 days after the treatment with 5.5 Gy × 2 + IBM is shown. The cells were collected from the recipients and stained with FITC-anti-H-2^b mAb or FITC-anti-H-2^k mAb to detect the donor- or host-derived cells (gated as R1). The cells were then stained with PE-anti-c-kit and biotinated mAbs (anti-CD4, anti-CD8, anti-B220, anti-CD11b, and anti-Gr-1 mAbs) plus streptavidin-RED670. The donor- or host-derived hemopoietic progenitor cells (c-kit⁺/Lin⁻ cells) were observed (gated as R2), and the percentages of these cells to total cells were calculated, respectively. The FACS profile of the negative control, in which the cells were stained with isotype-matched biotinated-IgG2a/IgG2b plus streptavidin RED670 and PE-IgG2a (instead of PE-anti-c-kit mAb), is also shown. (B) Kinetic analysis of donor- or host-derived progenitor cells. The percentages of donor (closed symbols and straight lines) or host (open symbols and dashed lines) of c-kit⁺/Lin⁻ progenitor cells in the bone marrow, spleen, and liver (HMNCs) in MRL/lpr mice treated with 5.5 Gy × 2 + IBM (●, ○, tibia; ♦, ⋄, femur), 5.5 Gy × 2 + PV (▴, ▵), or 5.5 Gy × 2 + IV (▪, ■) are shown. The results are expressed as the mean ± SD of 6 mice. Symbols representing the sites of the injection of BMCs are shown next to the right-hand figure. (●) Represent donor-derived BMCs collected from the tibia, where the donor BMCs were directly injected, and the (♦) show donor-derived BMCs obtained from the femur, where no donor BMCs were injected.