Fig. 2

Cultured leukemic cells maintain the stem cell capacity. a Representative FACS analysis of CD34 and CD38 expression profiles in primary B-ALL cells from patient #1 in OP9 co-culture at indicated time points. b B-ALL cells from xenografts of patients #1, #4, and #7 were co-cultured with OP9 stromal cells. After 6 weeks, cultured B-ALL cells were subjected to FACS analysis. Then CD34⁻CD38⁺ populations were enriched from cultured B-ALL cells and were subsequently injected into groups of NSI mice for serial transplantations. Eight weeks after transplantation, BM cells from xenografts were subjected for FACS analysis. Representative FACS analysis of gated CD45⁺ cells from xenografts or co-cultures