Ex vivo expansion of Tregs with rATG. (A) Effects of different immunosuppressive drugs on expansion of CD4⁺CD25^high and CD4⁺CD25^high-FOXP3⁺ T cells. Representative flow cytometric data are shown. (B) Summary of flow cytometric results. Changes of percentage and absolute number of Tregs, as well as percentage of CD4⁺CD25⁻ T cells, after treatment with different immunosuppressive drugs are shown. Data are mean plus or minus SEM (n = 10). Statistical significance was determined by an unpaired t test.