Figure 2. High peripheral blood myeloid chimerisms in busulfan-treated chimeras.

A) Representative FACS dot plots showing the expression of GFP in blood granulocytes, monocytes, B cells and T cells of busulfan-treated and irradiated CX₃CR1^GFP/+ → CX₃CR1^+/+ chimeras and untreated mice four weeks after bone marrow transfer. Percentages of the respective cell populations are indicated. CX₃CR1^+/+ mice served as untreated controls. B) Quantitative assessment of GFP⁺ expression in overall monocytes (SSC^loCD11b⁺) and the two monocyte subsets SSC^loCD11b⁺Ly6C^hi and SSC^loCD11b⁺Ly6C^lo out of all SSC^loCD11b⁺ cells. Data depict high reconstitution efficiencies and comparable chimerisms in both groups. One symbol represents one mouse (Busulfan-treated: filled circle; irradiated: filled squares). Mean ± SEM are shown. Six to seven animals per group were analysed. C) Photograph showing change of fur color 16 weeks after treatment. Irradiation leads to a loss of fur color, whereas busulfan-treated animals remain unaffected. Top: untreated animal, middle: whole-body irradiated animal, bottom: busulfan-treated mouse.