Short-term hematopoietic engraftment in NSγ mice. (A-C) Human hematopoietic engraftment was quantified based on the number of CD45⁺ cells detected per microliter of peripheral blood. Three panels present these data from 4 (A), 7 (B), and 10 weeks (C) after transplantation, respectively. At each time point, the data were stratified based on the transplant doses of ALDH^br CD34⁺ cells that each mouse received. Arrows indicate the first time point when CD45⁺ cells were observed for each cell dose. *Indicates a significant difference (P < .005) in chimerism between transplant doses of 3000 and 10 000 at 4 weeks after transplantation; ** and *** indicate significant increases (P < .05) in chimerism between 4 and 7 weeks for doses of 10 000 and 30 000 cells, respectively. The levels of chimerism observed 10 weeks after transplantation were not significantly different from those observed 7 weeks after transplantation. (D-G) In one cohort of 14 mice, the hematopoietic chimerism to the blood was compared with engraftment to the bone marrow 4 weeks after transplantation. Human CD45⁺ cells were detected within the peripheral blood at the highest transplant doses (D) and in the bone marrow (E). In panels F and G, total bone marrow cells were first gated to examine human CD45⁺ cells that did not express murine CD45 (not shown). Those cells included CD33⁺ myeloid cells (F), CD34⁺ progenitors (F), and human CD19⁺ B cells (G). CD3⁺ T cells were not detected (G).