Optimization of duration and rATG dose for treatment of PBMCs. (A) Kinetics of Treg expansion in PBMCs treated with rATG. (B) Dose-response of rATG in expansion of Tregs and percentages of CD4⁺CD25^high T cells and CD4⁺CD25^highFOXP3⁺ T cells are shown. (C) Apoptosis of lymphocytes induced with rATG, rIgG, hATG, hIgG, or CsA. Each data point represents a mean plus or minus SEM of 3 independent experiments.