HUBEC-culture increases the frequency of SRCs within adult human bone marrow

. (A) NOD/SCID mice (n = 47) received transplants of fresh ABM CD34⁺ cells over a range of doses, and the engraftment frequencies at each dose are plotted. The resultant curve indicates the estimated frequency of SRCs within this population. (B) NOD/SCID mice (n = 47) received transplants of the progeny of ABM CD34⁺cells cultured with HUBECs plus GM-CSF plus IL-3 plus IL-6 plus SCF plus flt-3 ligand. The engraftment frequencies are plotted at each dose, and the resultant curve indicates the frequency of SRCs within this population. The numbers shown within each box indicate the calculated frequency of SRC using the maximum likelihood estimator.