Infiltration of human CD45⁺ cells in the organs of the huPBMC-RAG2^-/- γc^-/- chimeras. Immunohistochemical evaluation (huCD45) was performed in 15 mice in the third experiment. Infiltration of human CD45⁺ cells at day 16 is shown in the various organs of the mice (right) compared with control slides (left). Original magnification, × 10.