miR-17∼92a deficient Tregs display increased apoptosis and defective proliferation.

<p>(<b>A</b>) Analysis of Treg apoptosis in <i>Mir17∼92a^fl/fl Foxp3^{CreYFP/CreYFP(Y)}</i> (KO) and <i>Mir17∼92a^fl/+ Foxp3^{CreYFP/CreYFP(Y)}</i> control (WT) mice. The Tregs from spleen and lymph node were identified as TCRβ⁺YFP⁺CD25^hi. Littermate KO and WT pairs (n = 5) were analyzed at ∼8 weeks of age. (<b>B</b>) Analysis of Treg proliferation by BrdU incorporation. The Tregs were identified as TCRβ⁺Foxp3⁺CD25^hi. Littermate KO and WT pairs (n = 5) were analyzed at ∼8 weeks of age. The BrdU treatment and analyses were performed over two experiments. (<b>C</b>) CFSE-labeled CD4⁺ T cells were transferred into sublethally irradiated CD45.1 recipients. After 8 days, the spleen and lymph nodes were harvested and pooled, and the transferred CD45.2 cells were analyzed for division by measuring CFSE dilution. Each data point represents a recipient transferred with cells from an individual donor KO or WT mouse (n = 4). The transfers and analyses were performed over two experiments.