Figure 8.

Persistent mIL-2/CD25 lowers anti-IAA titers and inhibits Tfh cells. Mice were treated for 10 weeks with HBSS or mIL-2/CD25 (4 and 20 µg) and assayed 72 h after the last injection. A: Assessment of IAA levels after the 10-week treatment period. Data points above the horizontal line in the graph are considered IAA⁺. Data (n = 9/group) were analyzed by χ² test as a function of IAA⁺ or IAA⁻. Representative contour plots (B) and quantitative data (C) of Tfh cells within the indicated tissues after gating on CD4⁺Foxp3⁻ T cells. Data are expressed as the number of T follicular helper (Tfh) in 1 × 10⁶ of CD4⁺Foxp3⁻ T cells. Data (n = 6–10/group) are shown as the mean ± SEM and analyzed by one-way ANOVA (Kruskal-Wallis test) and Dunn multiple-comparison test. Significance was assessed in comparison with mice treated with HBSS. *P ≤ 0.05; ****P ≤ 0.0001.