CD4 and sarcoidosis: The Th17 cell population in PBMCs was increased in sarcoidosis patients (1.61% ± 1.09%) compared with HCs (0.51% ± 0.43%) (p < 0.05), whereas CD4+ CD25high Foxp3+ Tregs were decreased in sarcoidosis patients (0.95% ± 0.91%) compared to HCs (2.68% ± 2.15%) (p < 0.05) (Figure 3A).