Figure 2.

Decreased number of S6^wt/del T cells in the spleen and lymph nodes is a consequence of their decreased survival. (A) Total cell number in spleens from female (F) and male (M) S6^wt/lox/CD4-Cre^- and S6^wt/lox/CD4-Cre⁺ mice (n = 10, for each group). Error bars represent standard deviation. For females, (^*) p < 0.05 versus S6^wt/lox/CD4-Cre^- splenocytes; and for males, (^**) p > 0.05 versus S6^wt/lox/CD4-Cre^- splenocytes (Mann Whitney U-test). (B,D) FACS analysis of cells from S6^wt/lox/CD4-Cre^- and S6^wt/lox/CD4-Cre⁺ spleens. (C,E) FACS analysis of cells from S6^wt/lox/CD4-Cre^- and S6^wt/lox/CD4-Cre⁺ lymph nodes (n = 35, for each group). (^*) p < 0.001 versus S6^wt/lox/CD4-Cre^- CD3⁺ cells (t-test). Genotypes are as indicated above the panels. Cell surface markers are shown as coordinates. The numbers in quadrants refer to percentage of respective cell population of live cells. (F) Southern blot analysis of genomic DNA from S6^wt/lox/CD4-Cre^- and S6^wt/lox/CD4-Cre⁺ T cells purified from lymph nodes of 8-wk-old mice using the S6 intron-specific probe. (G) Six-week-old S6^wt/_lox/CD4-Cre^- and S6^wt/lox/CD4-Cre⁺ mice were daily injected intraperitoneally with 100 μg/g of body weight 5-BrdU (Sigma) in 200 μL of PBS during the indicated time periods; 5-BrdU incorporation into DNA was determined by flow cytometry. The percentages of 5-BrdU-positive lymph node T cells are shown. The experiment is a representative of four independent experiments. (H) CFSE-labeled S6^wt/lox/CD4-Cre⁺ or S6^wt/lox/CD4-Cre⁺ T cells (10 × 10⁶) were transferred into wild-type recipients by intravenous injection, and the percentage of CFSE-labeled T cells was determined in spleens. The total number of T cells in different recipients was similar. The experiment is a representative of three independent experiments.