Flow cytometric analysis of human cells in NOD/SCID mouse BM around 6 weeks after transplantation reveals that BCR/FGFR1 expression directs the differentiation to myeloid and erythroid cell fates. (A) Engraftment at 6 to 7 weeks after transplantation of human cells transduced with BCR/FGFR1, ZMYM2/FGFR1, or the MIG control vector. (B) Phenotype of human cells in the BM of BCR/FGFR1 (black), ZMYM2/FGFR1 (gray), or MIG (white) mice at 6 to 7 weeks after transplantation, revealing that BCR/FGFR1 significantly directs grafted cells toward the myeloid and erythroid cell lineages. Data are presented as the mean value of all analyzed mice with error bars representing SEM (for data at 9-12 weeks after transplantation, see supplemental Figure 4B). (C) FACS plots showing the gating and differentiation pattern of human cells (GFP⁺ and/or CD45⁺; top panel) in BM from representative MIG, ZMYM2/FGFR1, or BCR/FGFR1 mice, as detected by cell surface expression of CD34, CD19, CD33/15, and CD235a. (D) FACS plot showing increased erythroid differentiation of human cells in BM of an additional BCR/FGFR1 mouse.