Effect of IL-7 overexpression on αβ T-cell development. Panels A-B represent absolute thymocyte counts from 6- to 12-week-old TgA (n = 11), TgH (n = 7), TgB (n = 12), and negative littermates (n = 15). *P < .0001; ⁺P < .05. The 2 bar graphs depict absolute numbers (mean ± SEM) of total thymocytes and DP cells (A) and CD8⁺TCR^lo, CD8⁺TCR^hi, and CD4⁺TCR^hi thymocytes (B) from Tg⁺ and Tg^– mice. Error bars indicate SEM. (C) Western blot for Bcl-2 on sorted DP thymocytes from all 3 Tg lines and normal B6 mice. Actin was used as a control. (D) Dot plot analysis of CD4 and CD8 expression on thymocytes from representative 8-week-old Tg⁺ (A, H, and B lines) versus Tg^– control mice. The percentages of DN, DP, CD4SP, and CD8SP in each sample are indicated. The gate is used to analyze the DP cells. (E) Maturation markers, IL-7 Rα, and Bcl-2 expression in DP thymocytes from representative Tg⁺ and Tg^– mice. The shaded areas represent the marker of interest, and the open areas represent the negative isotype controls. The percentage of positive cells for each marker is shown.