Abstract: Wen Yunshi, Qin Haihong, Xu Jinhua. Department of Dermatology, Huashan Hospital, Fudan University, Shanghai 200040, China Corresponding author: Xu Jinhua, Email: hsyyxjh@163.com 【Abstract】 Objective To investigate the expressions of miR-17 and miR-20a in CD4+ T cells from patients with systemic lupus erythematosus （SLE） and their correlations with disease activity. Methods CD4+ T cells were isolated from the venous blood of 30 patients with SLE and 18 healthy human controls. RNA was extracted from the CD4+ T cells, and real-time fluorescence-based quantitative PCR （qPCR） was performed to determine the expression levels of miR-17 and miR-20a. The intergroup comparison of miR-17 and miR-20a expression levels was done using t test and Mann-Whitney test, and the correlations of miR-17 and miR-20a expressions with clinical parameters were assessed using Pearson or Spearman correlation coefficients. Results The patients with SLE showed increased expression levels （2－△Ct） of miR-17 and miR-20a compared with the healthy controls （0.24 ± 0.08 vs. 0.15 ± 0.06 for miR-17, 0.19 ± 0.10 vs. 0.12 ± 0.09 for miR-20a, both P < 0.05）. The miR-17 and miR-20a expression levels were also significantly higher in patients with active SLE than in those with inactive SLE and the healthy controls （0.27 ± 0.07 vs. 0.20 ± 0.05 and 0.16 ± 0.08 for miR-17, 0.22 ± 0.10 vs. 0.15 ± 0.07 and 0.13 ± 0.09 for miR-20a, all P < 0.05）, but similar between the patients with inactive SLE and healthy controls （both P > 0.05）. The expression levels of both miR-17 and miR-20a were positively correlated with SLE disease activity index （SLEDAI） （r = 0.45, 0.38, respectively, both P < 0.05） and anti-dsDNA antibody level （r = 0.54, 0.46, respectively, both P < 0.05）, but negatively correlated with serum C3 levels （r = －0.43, －0.42, respectively, both P < 0.05）. Conclusions The expressions of miR-17 and miR-20a are increased in CD4+ T cells from patients with SLE, and correlated with the disease activity in SLE.

Key words: Lupus erythematosus, systemic, CD4-positive T-lymphocytes, miR-17, miR-20a