Flow cytometric analysis of the human B-cell population present in engrafted NOD/SCID mice treated with various cytokines. (A) Four NOD/SCID mice were transplanted with one CB donor and the BM was analyzed 6-weeks later for the presence of CD19⁺and/or CD20⁺ human B lymphocytes. These analyses were performed on gated CD45⁺ human cells. The level of human cell engraftment is shown in brackets for each mouse. In all cases the mice were treated with the indicated cocktail of cytokines every other day for the entire experiment. Lymphocytes (red) were distinguished from blasts (green) and myeloid cells (blue) according to their size and morphology using forward and side-scatter characteristics. (B) Mice were transplanted with CD34⁺CD38⁻ cells for the no GF, SCF/IL-3/GM-CSF, FL/SCF/IL-3 treatment groups, or CD34⁺Lin⁻ cells for the IL-7/FL treatment group.