Circulating human cells in the peripheral blood of NOD/SCID mice.

Peripheral blood cells from the same mouse were gated as described above (A) and tested for expression of human CD45, a human-specific panleukocyte marker (B). Human primitive CD133⁺CD34⁻CD38⁻ (C) and CD133⁺CD34⁺CD38⁺ (D) stem cells were detected. CD19 (a human pan–B-cell marker; E), CD56 (an NK-cell marker; F), and CD3 (a human pan–T-cell marker; E-F) were also expressed. Human cells with a T-cell phenotype expressed CD2 (G) as well as CD4 and CD8 (H), and the majority of them expressed TCRγδ (I).