Blood lymphocyte counts after RAG1 retroviral-mediated gene transfer in RAG-1-deficient mice. Peripheral T lymphocytes (A) and B lymphocytes (B) were counted and immunostained at various times. The number of tested mice was as follows: RAG-1^-/- (n = 4), RAG1-transduced mice (RAG1-TM, n = 9), and control mice (WT-CTRL, n = 8). Data are expressed as means ± standard deviation (SD). ^*The comparison of these values is not statistically significant. (C) Blood lymphocyte phenotype after RAG1 retroviral-mediated gene transfer in RAG-1-deficient mice 6 months after treatment. Flow cytometry analysis was performed on RAG-1^-/-, RAG1-TM, WT-CTRL, and wild-type mice to detect the proportion of mature T-cell subsets (CD4⁺CD3⁺ or CD8⁺CD3⁺) and mature B cells (B220⁺IgM⁺IgD⁺). Leukocyte counts were 1000 cells/mm³, 3200 cells/mm³, 3000 cells/mm3, 2400 cells/mm3, and 5000 cells/mm3, respectively, for RAG-1^-/-, RAG1-TM (3 Gy), RAG1-TM (8 Gy), WT-CTRL, and wild-type mice. Data are representative of 1 of 9 RAG1-TM mice that gave similar results. Percentages represent the proportion of cells expressing CD4, CD8, B220, IgM, or IgD markers.