Ex vivo expansion of BM cells from mice treated with 5FU. The two upper diagrams represent the cellularity (A) and the number of CFU-GMs (B) of BM samples obtained at different days after 5FU administration and incubated for 3 days in vitro. The lower part of the figure represents the influence of the incubation period on the cellularity (C) and CFU-GM numbers (D) generated by BM samples obtained 9 days after 5FU treatment. The dotted line represents the cellularity (A and C) and the number of CFU-GMs (B and D) generated by the femoral BM of normal untreated mice. The figure represents the results obtained in three independent experiments.