Fig. 5.

Inhibition of mTOR signaling during T cell activation, either by rapamycin or amino acid depletion, induces foxp3 in synergy with TGF-β. Naive CD4⁺ T cells from female A1.RAG1^−/− mice were stimulated with syngeneic bmDC in the presence of 100 nM DBY peptide for 4 days at 37 °C under the conditions indicated. Cells were surface-stained for CD4 and after fixation and permeabilization for foxp3, p4E-BP1, and pS6 they were analyzed by flow cytometry. Dot plots are shown for foxp3 versus pS6 after gating on CD4⁺ cells within the live lymphocyte forward and side scatter gates. Percentages of foxp3⁺ for CD4⁺ T cells are indicated. pS6 staining positively correlated with p4E-BP1 staining.