Thymus profile after RAG1 retroviral-mediated gene transfer into RAG-1-deficient mice. Mice receiving transplants were killed 6 months after RAG1 gene transfer. Flow cytometry analysis was performed on total thymic cells for CD4 and CD8 staining. For the CD25 and CD44 distribution analysis, the dot-plot window was gated on the CD4^-CD8^- cells. The dot plots are representative of one experiment: n = 4 for the RAG-1-deficient mice (RAG-1^-/-), n = 5 for the RAG1-transduced mice (RAG1-TM, 3 Gy), n = 4 for the RAG1-transduced mice (RAG1-TM, 8 Gy), n = 8 for the control mice (WT-CTRL), and n = 4 for the same age wild-type C57BL/10 mice. Percentages represent the proportion of cells expressing CD4, CD8, CD25, or CD44 markers.