Figure 2.

Proportion of residual Tregs 4 weeks after MLTC. Before MLTC, the Tregs were depleted using a human CD4⁺CD25⁺ isolation kit. Following Treg depletion, a control group (Treg-depleted group), 1% Treg-added group and 5% Treg-added group were subjected to MLTC for 4 weeks. At 4 weeks after MLTC, the populations of Tregs were analyzed by flow cytometry with a FACSCalibur instrument. (A) The proportion of Foxp3⁺/CD4⁺ cells is shown. (B) The relative ratio of the mean fluorescence intensity of Foxp3⁺CD4⁺CD25⁺/Foxp3⁺CD4⁺CD25⁻ is shown. The Tregs remained for at least 4 weeks according to the initial proportion added following MLTC in each group. Tregs, regulatory T cells; MLTC, mixed lymphocyte-tumor cell culture; FACS, fluorescence-activated cell sorting.