Proliferation of IL-13+T cells from control and asthmatic subjects. CFSE-labeled PBL from female control (n = 6) and female atopic asthmatic subjects (n = 7) were cultured 6-d with IL-2 and anti-IL-12 or 5-d with CD3+CD28 monoclonal antibody + IL-2 + anti-IL-12, and then stimulated and analyzed for cytokine production. (A) Proportions (mean ± S.D.) of cells in IL-13+ and IL-13- T cell populations (y-axis) that had undergone the indicated number of divisions (x-axis). (B) Compiled analysis for: cell numbers of the indicated T cell population, expressed as a percent of day 0 values, geometric mean + 95% CI (left panel); the average number of divisions the indicated T cell population underwent during culture, mean ± SD (middle panel); the percentage loss of progenitors of the indicated T cell population, mean ± SD (right panel). * p < 0.05 for difference in (geometric) mean.