Analysis of human cell engraftment in NOD/SCID mice. Murine bone marrow cells (A) and human peripheral blood cells (B) were stained with CD45 as negative and positive controls for antibody specificity. Cell samples were stained with IgG₁ as an isotype control (C) and gates were set to exclude ≥99% of cells in the matched isotype control. This gate was then used to determine the proportion of positive cells in the CD45-stained murine samples (D). FSC, forward light scatter.