Percentage of CD34⁺ cells contained in fresh and ex vivo–expanded BM and MPB grafts and that detected in BM- and spleen-homed cells 40 hours AT.

BM and MPB cells partially immunomagnetically enriched for CD34⁺ cells (to prepare grafts containing approximately 50% CD34⁺ cells) were either stained with CFSE and transplanted fresh into conditioned NOD/SCID recipients or expanded in vitro as described in the legend of Figure 2. Expanded cells were then stained with CFSE on day 5 and transplanted into conditioned NOD/SCID recipients. Percentage of CD34⁺ cells was determined in fresh (Fresh BM and Fresh MPB) and ex vivo–expanded (Exp BM and Exp MPB) grafts before transplantation (In Graft) and as a percentage of human CFSE⁺ cells detected flow cytometrically in the marrow (In BM) and spleen (In Spl) of transplant recipients 40 hours later. Each bar represents the mean ± SD (where applicable) of 3 to 4 measurements for fresh BM and MPB and expanded BM cells and one measurement for expanded MPB cells. Data were collected from 8 separate experiments.