Figure 6.

Treg suppressive activity analysis. CD4⁺CD25⁺ Tregs were isolated from allograft recipients that had been treated with anti-CD154 mAb or isotype IgG on day 14 post surgery. CD4⁺CD25⁻ T effector cells were isolated from naïve BALB/c mice, labeled with 0.5 μM CFSE, and then stimulated with mitomycin C-treated C57BL/6 splenocytes for 72 h in the presence or absence of Tregs at the indicated ratio. The proliferation of CFSE-labeled CD4⁺CD25⁻ T effector cells was measured by flow cytometry. Quantitative results are shown. Data presented are the mean ± standard deviation of three independent experiments. Student’s t-test was performed to evaluate statistical significance. ^*P<0.01; ^**P<0.001; ^***P<0.0001. CFSE, carboxyfluorescein diacetate succinimidyl ester.