Variation in CRU numbers in recipients of neo-andHOXB4-transduced bone marrow cells over 1-year period. The number of CRU in femurs of cohorts of HOXB4 recipients from 3 different experiments ([▪] experiment no. 1, [⧫] experiment no. 2, and [•] experiment no. 3) and neo recipients from 2 different experiments (□ and ◊) were evaluated using the CRU assay. The results shown are expressed as the mean ± 95% confident interval of the CRU numbers in 1 femur of neo and HOXB4 mice at the various time points after transplantation. The number ofneo and HOXB4 mice analyzed at each time point are shown in Fig 1B. The shaded area represents the normal number of CRU measured in the femoral cavity of an unmanipulated (C57Bl/6J × C3H/HeJ)F1 mouse.9