Expansion of CD4⁺CD25⁺ FOXP3⁺ Treg cells by monocyte-derived cytokine-matured DCs. (A) CD3 purified T cells were cultured alone or with monocyte-derived Cyt-DCs in the absence or presence of graded doses of IL-2 (0-200 U/mL). After 7 days, the numbers of CD4⁺ FOXP3⁺ Treg's were monitored by flow cytometry. Data (mean ± SD) show a summary of 5 experiments. P < .05 for comparisons with Cyt-DCs. (B) T cells were cultured either alone or with Cyt-DCs, and CD4⁺ FOXP3⁺ T cells were enumerated by FACS on days 0, 1, 2, 4, and 7. Data (mean ± SD) show a summary of 2 experiments. (C) T cells were labeled with CFSE and cultured alone or with Cyt-DCs, and proliferation monitored by flow cytometry on day 5. The figure represents 1 of 4 similar experiments.