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Figure S5. Induced Foxp3⁺ cells suppress T cell proliferation in vitro. (A) CD4⁺eGFP² T cells were cultured with 10⁴ purified CD103⁺ or CD103² MLN DCs and 1 µg/ml of soluble anti-CD3. Some wells additionally contained 3 ng/ml rhTGF-β, 100 nM RA, or 1 µM each of the RA receptor inhibitors LE540 and LE135. On day 5, cells were stained for α4β7, and Foxp3⁺ T cells were detected by eGFP expression. Plots are gated on viable cells, by exclusion of 7-AAD⁺ dead cells, and numbers represent the percentage of viable cells in each quadrant. (B) CD4⁺eGFP² T cells were cultured with 10⁴ purified CD103⁺ MLN DCs, 3 ng/ml rhTGF-β, and 1 µg/ml of soluble anti-CD3. Converted CD4⁺eGFP⁺ cells were sorted and cultured at varying ratios with 5 x 10⁴ freshly isolated CD4⁺GFP² T cells, 10⁵ APC, and 0.5 µg/ml anti-CD3 for 72 h. 1 µCi/well of [³H]TdR was included for the final 8 h. The suppressive capacity of these cells was compared with freshly isolated CD4⁺eGFP⁺ T reg cells. Graph depicts mean [³H]TdR incorporation in cpm.