Kinetics of repopulation of NOD/SCID mice by IBMI-CD34− and CD34+ SRCs.
In this study, a group of 18 mice (8 weeks old) received transplants of 5 × 103 Lin−CD34high or 5 × 104 Lin−CD34− cells isolated from 6 CB samples. Groups of 3 mice were killed at 5, 8, and 12 weeks after transplantation. At each time point, BM cells obtained from pairs of femurs, tibiae, and humeri were analyzed by flow cytometry for their contents of human CD45+ cells. Open and gray columns represent the values of CD45+ cells derived from CD34+ SRCs and IBMI-CD34− SRCs, respectively. Horizontal bars represent the respective medians. Both CD34+ SRCs and IBMI-CD34− SRCs showed signs of engraftment at 5 weeks after transplantation. The human CD45+ cell rate for CD34+ SRCs significantly (P < .05) increased from 5 weeks to 8 weeks, while that for IBMI-CD34− SRCs significantly (P < .05) increased from 8 weeks to 12 weeks.