Figure 7. Autophagy is preferentially required for activated T_reg cell maintenance.

(a,b) Flow cytometry analyzing the expression of YFP-Foxp3 in GFP⁺ and GFP⁻ CD4⁺ T cells (a) and active caspase-3 in GFP⁺ and GFP⁻ T_reg cells (b) in the spleen of Rag2^GFPFoxp3^CreAtg7^+/fl and Rag2^GFPFoxp3^CreAtg7^fl/fl mice. Numbers adjacent to outlined areas indicate percent YFP-Foxp3⁺ cells (a) and caspase-3⁺ cells (b). (c) Representative images (scale bars, 5 μm) (left) and quantification of the number of GFP-LC3⁺ puncta per cell (right) in cT_reg and eT_reg cells purified from the spleen of GFP-LC3 mice (n=5 mice). (d,e) Flow cytometry analyzing the proportion of CD44^hiCD62L^lo eT_reg cells among total T_reg cells in the spleen of Foxp3^CreAtg7^+/fl and Foxp3^CreAtg7^fl/fl mice (n=6 mice per genotype) (d, left) and Foxp3^CreAtg7^+/fl and Foxp3^CreAtg7^fl/fl chimeras (n=4 mice per group) (e, left), and frequency of CD44^hiCD62L^lo eT_reg cells (d,e, right). Numbers adjacent to outlined areas indicate percent CD44^hiCD62L^lo eT_reg cells (d,e, left). (f,g) Flow cytometry analyzing the expression of active caspase-3 (f) and p-S6 (g) in CD44^loCD62L^hi cT_reg cells and CD44^hiCD62L^lo eT_reg cells in the spleen of Foxp3^CreAtg7^+/fl and Foxp3^CreAtg7^fl/fl mice. Numbers adjacent to outlined areas indicate percent caspase-3⁺ cells (f), and numbers above graphs indicate MFI of p-S6 (g). * P < 0.05 (two-tail unpaired Student’s t-test in c–e). Data are representative of five (a,f), three (b,g), or four (e) experiments, or pooled from two out of two (c) or five out of five (d) experiments (mean ± s.e.m in c–e).