Imbalance of T effector/Treg cells and dysregulation of miR-21-5p in patients with VIT. Percentages of (A) Th1, (B) Th17, (C) Th22 and (D) Treg cells in CD4+ T cells of peripheral blood mononuclear cells in patients with VIT and healthy controls (n=15 for each group) were measured via flow cytometry. Protein levels of (E) IFN-γ, (F) IL-17A and (G) IL-22 in the peripheral blood of patients with VIT and healthy controls were measured via enzyme-linked immunosorbent assay. Relative expression levels of (H) Foxp3 and (I) miR-21-5p in the peripheral blood of patients with VIT and healthy controls were measured via reverse transcription-quantitative PCR. GAPDH and U6 were used as the internal controls, respectively. **P<0.01; ***P<0.001. VIT, vitiligo; Th, T helper; IFN, interferon; IL, interleukin; miR, microRNA; Treg cells, regulatory T cells.