CD8⁺iTregs suppress Teff expansion and differentiation. Lethally irradiated BALB/c mice were used as recipients, and the procedures are described in Figure 3A. H2b⁺ Ly5.1⁺ cells were analyzed as Teffs. (A) Ability of transferred CD8⁺ iTregs (Ly5.2⁺) to suppress Teff (Ly5.1⁺) expansion. IFN-γ expression of CD4⁺ (B) and CD8⁺ (C) Teffs. Data are combined from 2 independent experiments (n = 7 per group). *P ≤ .05, **P ≤ .01, ***P ≤ .001, ****P ≤ .0001, 1-way ANOVA.