Fig. 7.

Progressive reduction of T_reg cell-specific markers in induced Foxp3⁺ iT_reg cells of COPD subjects at different GOLD stages. Cumulative data of the expression of T_reg cell-specific markers (CTLA-4 and PD-1) and Ki-67 in induced FoxP3-all⁺ (Upper) and FoxP3-E2⁺ (Lower) cells from NS healthy subjects; S healthy subjects; and COPD subjects at GOLD stage II, GOLD stage III, and GOLD stage IV, as indicated, are shown. Data are from at least n = 5 subjects, and are expressed as mean ± SEM. Each symbol represents an individual healthy or COPD subject as indicated. *P < 0.05; **P < 0.01; ***P < 0.001 by 2-tailed Mann–Whitney test.