Human cytokine KI mice support engraftment of human mobilized PB CD34⁺ cells. (A) Representative fluorescence-activated cell sorter (FACS) analysis of the frequency of mouse and human CD45⁺ cells in BM in newborn mice 14 weeks posttransplantation. Numbers besides gated areas indicate percentages of cells. (B) Engraftment of hCD45⁺ cells in BM of newborn mice 10 to 16 weeks posttransplantation. Left panel indicates percentage of hCD45⁺ cells among total CD45⁺ cells. Right panel indicates absolute number of hCD45⁺ cells per hind legs (2 femurs and tibias). Each symbol represents an individual mouse; bars indicate mean values; n = 11 (NSG), n = 3 (SRG), n = 22 (MSTRG), n = 4 (MISTRG). Conv, conventional; KI, human cytokine KI. *P < .05; ***P < .001 (1-way analysis of variance [ANOVA] Kruskal-Wallis test with Dunn’s multiple comparison test). (C) hCD45⁺ cell engraftment in BM of newborn mice from split, matched individual donors. Each symbol represents mean frequency of hCD45% cells among total CD45⁺ cells. Mean frequency of human CD45⁺ cells in Conv vs KI mice was significantly different. *P < .05 (Conv vs KI; paired t test). (D) Engraftment of hCD45⁺ cells in blood (left) and spleen (right) 10 to 16 weeks posttransplantation. Each symbol represents an individual mouse; bars indicate mean values; n = 11 (NSG), n = 3 (SRG), n = 22 (MSTRG), n = 4 (MISTRG). *P < .05; ***P < .001 (1-way ANOVA Kruskal-Wallis test with Dunn’s multiple comparison test). (E) Engraftment of hCD45⁺ cells in BM, blood, and spleen in adult mice 12 to 16 weeks after transplantation. Panel shows percentage of hCD45⁺ cells among total CD45⁺ cells in each organ. Each symbol represents an individual recipient engrafted with hCD45⁺ cells; bars indicate mean values; n = 2 (NSG), n = 4 (MISTRG). (F) Representative FACS plots for hCD34⁺CD38⁺ and hCD34⁺CD38⁻ cells in newborn recipients gated on mCD45⁻ Lineage (Lin)⁻ hCD45⁺ cells. Numbers beside gate indicate percentages of cells. (G) Frequency (left 2 graphs) as well as absolute number (right 2 graphs) of hCD34⁺CD38⁺, hCD34⁺CD38⁻ cells per hind legs. Each symbol represents an individual newborn recipient engrafted with hCD45⁺ cells; bars indicate mean values; n = 5 (Conv; 2 NSG and 3 SRG), n = 19 (KI; 15 MSTRG and 4 MISTRG). *P < .05 (Mann-Whitney U test).