(a) Comparison of the average percentage of human CD45+ immune cells within the bone marrow of cohorts engrafted with HSPCs only (first six cohorts on the left, shaded in gray) and those engrafted with an HSPC- MSC mixture, along with the number of mice in each cohort. (b) Chart comparing the average CD45+ cell percentage (light green) and the average CD34-45+ HSPCs percentage (dark green) in mouse cohorts generated using only HSPCs and those created from HSPC-MSCs. *P=0.007. (c) Comparison of the percentage of human T cells, B cells, and monocytes found in the blood of mice engrafted with HSPCs and HSPC-MSCs. *P=<0.01, **P=0.01, ***P<0.01. Also compared are the percentages of total human CD45+ cells observed in these two mouse types. ****P<0.01. (d) Comparison of the percentage of human T cells, B cells, and monocytes found in the spleen of mice engrafted with HSPCs and MSPC-MSCs. *P<0.01, **P<0.01, ***P<0.01.