Abstract: Objective: To detect the expression of Treg cells and Th17 cells in the patients with psoriasis vulgaris（PV）. Methods: Thirty-four PV and 18 healthy controls were enrolled in the study, and Treg cells, Foxp3 and Th17 cells of the blood were detected by flow cytometry. Results: The percentage of Treg cells and Foxp3 cells were（3.68±1.22）% and （0.53±0.19）%, which were significantly lower than those in normal controls（6.63±1.00）%, and （0.76±0.14）% (P﹤0.05). The percentage of Th17 cells was（2.20±0.78）%, which was significantly higher than that in normal controls （0.65±0.22）% (P﹤0.05). The expression of Treg cells and FOXP3+Treg cells was positively correlated (r=0.563, P﹤0.05), but the expression of Treg cells and Th17 cells was negatively correlated (r=-0.522, P﹤0.05). The correlation among Treg cells, Th17 cells, PASI score and duration of the disease was not significant (P﹥0.05).. Conclusion: The decrease in the expression of Treg cells and the increased response of Th17 cells may be the important factors for the immunological?imbalance in PV.

Key words: psoriasis vulgaris, regulatory T cells;Th17 cells, FOXP3, PASI score, flow cytometry