Abstract:

Wei Ming, Liang Yinghong, Tu Ling, Liu Jia, Gong Yanjie, Zhang Yihua, Yang Lu Clinical Laboratory, Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China Corresponding author: Wei Ming, Email: gushiweiming@126.com 【Abstract】 Objective To evaluate regulatory effects of miRNA-146a on peripheral blood CD4+ T lymphocytes from patients with psoriasis vulgaris, and to investigate the role of miRNA-146a in the pathogenesis of psoriasis vulgaris. Methods Totally, 30 patients with psoriasis vulgaris and 30 healthy human controls were enrolled into this study. Venous blood samples were obtained from these subjects, and CD4+ T lymphocytes were isolated from these samples by using magnetic activated cell sorting （MACS）. Real-time quantitative PCR （RT-PCR） was performed to measure the of miRNA-146a in peripheral blood CD4+ T lymphocytes, and enzyme-linked immunosorbent assay （ELISA） to determine plasma levels of interferon-γ （IFN-γ） and interleukin 4 （IL-4）. Some CD4+ T lymphocytes were divided into 3 groups to be transfected with 50 nmol/L negative control miRNA （control group）, miRNA-146a mimics （miRNA-146a group） or miRNA-146a inhibitor （miRNA-146a inhibitor group）. After 24-hour additional culture, flow cytometry was conducted to determine the number of Th1 and Th2 cells, Western-blot analysis and RT-PCR were performed to measure the protein and mRNA s of IFN-γ receptor α （IFN-γRα）, T-box expressed in T cells （T-bet） and GATA-binding protein-3 （GATA-3） respectively, and ELISA was carried out to determine the levels of IFN-γ and IL-4 in supernatants of CD4+ T lymphocytes. Results Compared with the healthy control group, the patient group showed significantly increased miRNA-146a in peripheral blood CD4+ T lymphocytes （243.81% ± 94.32% vs. 105.74% ± 22.93%, t = 6.653, P < 0.01） and plasma IFN-γ level （27.69 ± 7.64 ng/L vs. 9.75 ± 2.81 ng/L, t = 4.237, P < 0.01）. Moreover, miRNA-146a was positively correlated with plasma IFN-γ level in the patients （r = 0.837, P < 0.01）. After 24-hour culture in vitro, there was a significant increase in the number of Th1 cells, protein and mRNA s of T-bet, and supernatant level of IFN-γ, but a significant decrease in the protein of IFN-γRα in the miRNA-146a group compared with the control group （all P < 0.01）. However, no significant differences were observed in the number of Th2 cells, mRNA or protein s of GATA-3, or supernatant level of IL-4 among the control group, miRNA-146a group and miRNA-146a inhibitor group （all P > 0.05）. Conclusion miRNA-146a may play an important role in the pathogenesis of psoriasis vulgaris by participating in the regulation of peripheral blood CD4+ T lymphocytes via affecting Th1 cell differentiation and function.