Abstract:

Yang Ji, Yang Xue, Yang Jie, Li Ming Department of Dermatology, Zhongshan Hospital, Fudan University, Shanghai 200032, China （Yang J, Li M）; Department of Rheumatology, Huashan Hospital, Fudan University （Yang X）; Shanghai Blood Center, Shanghai 200051, China （Yang J） Corresponding author: Li Ming, Email: li.ming@zs?hospital.sh.cn 【Abstract】 Objective To evaluate the regulatory effect of hydroxychloroquine on in vitro differentiation of regulatory T cells （Treg）. Methods Fifteen milliliters of peripheral blood were obtained from a healthy human subject followed by isolation of monouclear cells and sorting of naive T cells. Then, the naive T cells were classified into two groups: control group cultured with the presence of tumor growth factor （TGF）?β and interleukin （IL）?2, experimental group cultured with the presence of 20 μmol/L hydroxychloroquine and inducing factors. The number and percentage of CD4+Foxp3+ Treg cells were determined by flow cytometry at days 0, 6, and 12. Results The number of Treg cells at days 0, 6, and 12 were （2 ± 0.4） × 104, （13.2 ± 5.2） × 104, and （143.5 ± 35.9） × 104 respectively in the control group, （2 ± 0.5） × 104, （2.4 ± 0.4） × 104, and （5.6 ± 3.5） × 104 respectively in the experimental group. There was a significant difference in the number of CD4+Foxp3+ Treg cells between the two groups at days 6 and 12 （t = 3.78 and 6.16, respectively, both P < 0.05）. At day 12, the percentage of CD4+Foxp3+ Treg cells was 79.7% ± 18.1% in the experimental group, compared to 16% ± 13% in the control group （t = 11.77, P < 0.01）. Conclusion Hydroxychloro?quine could inhibit the differentiation and proliferation of CD4+Foxp3+ Treg cells in vitro.