Treg cells from miR-181a/b-1^−/− mice display increased suppressive capacity.

(A) Production of cytokines by splenic CD4+ T cells and Treg cells after stimulation with PMA/ionomycin. Graphs represent quantification of the data from 3 independent experiments, n = 4–5 for each genotype. (B) In vivo suppression of homeostatic proliferation in lymphopenic Rag−/− mice by miR-181a/b+/− and miR-181a/b−/− Treg cells. Depicted is expansion of Tconv in the absence (no Treg cells) and presence of miR-181a/b-1+/− or miR-181a/b-1−/− Treg cells 14 days after coinjection of T cells. (C) Quantification and absolute numbers of recovered Tconv cells and Treg cells. Data are representative of 2 independent experiments, with n = 7–8 (recipient mice). Statistical analysis was performed using unpaired Student’s t test. Numerical values are available in S1 Data. CD, cluster of differentiation; IFN-γ, interferon gamma; IL, interleukin; miR-181, microRNA-181; PMA, phorbol 12-myristate 13-acetate; pos., positive; Tconv, conventional T; TCR, T-cell receptor; TNF, tumor necrosis factor; Treg cell, regulatory T cell.