Figure 1: Human T-cell reconstitution in peripheral blood of humanized HLA-Tg mice.

Panel (a) FACS analysis of blood, thymus and spleen of naïve (non-HSC infused) DRAGA, A2, and DRAG mice stained with HLA-A2 and HLA-DR4 Abs. Panel (b) four-to-six week old mice were infused with HLA-A2/DR4-positive HSC (10⁵/mouse, Supplementary Table S1) and examined 16–18 weeks later for reconstitution of human T cells in peripheral blood by FACS using CD3, CD4, and CD8 Abs. Data represent the percentage of mice having human T cells in blood. The cut-off for positive human CD3⁺ T cells was calculated as three times the standard deviation over the background levels of cells from naıve (non-HSC infused) DRAG mice that were stained with anti-human CD3 (0.17%). Z test indicated that the human T cell reconstitution rate in A2 mice (12 of 23) and NRG (3 of 7) was similar (p = 0.66), but significantly lower as compared to DRAGA (34 of 38, p = 0.001) and DRAG (39 of 43, p = 0.0004) mice. Panels (c,d) frequency of human T cells (CD3⁺), and human CD4 T and CD8 T cell subsets, in the reconstituted DRAGA, A2 and DRAG mice. Data represent values in individual mice on a mononuclear FSC/SSC gating. Horizontal lines represent mean values. Student t test indicated that A2 mice reconstituted significantly lower frequencies of total human T cells and CD4 T cells than DRAGA and DRAG mice (*p < 0.05), but similar frequencies of human CD8 T cells.