类风湿关节炎患者外周血单个核细胞中微RNA-31的表达及意义

Expression and significance of miRNA-31 in peripheral blood mononuclear cells of rheumatoid arthri-tis patients

目的探讨微RNA（miRNA）-31在RA PBMCs中的表达，及其与RA年龄、性别、疾病炎症指标和病情活动度间的关系。方法在知情同意的情况下，收集北京大学第三医院风湿免疫科56例RA患者，12例SLE患者，6例SS患者和30名健康对照的外周血，通过Ficoll-Hypaque密度梯度离心法分离PBMCs，提取RNA并进行反转录，实时定量PCR检测RA、SLE、SS患者和健康对照组PBMCs中miRNA-31的表达。再根据RA子DAS28将RA患者分为高、中、低疾病活动期和缓解期，比较不同活动期中miRNA-31的表达情况。采用t检验或Mann-Whitney U检验进行统计学分析。结果RA患者PBMCs中miRNA-31的表达是健康对照组的7.25倍（P=0.003 8）；其中，高疾病活动组RA患者PBMCs中miRNA-31的表达是健康对照组的10.63倍（P=0.01），中疾病活动组miRNA-31的表达是健康对照组的8.95倍（P=0.000 3），而低疾病活动组和缓解期RA患者miRNA-31的表达与对照组之间差异无统计学意义；SLE患者PBMC中miRNA-31的表达降低，SS患者PBMCs中miRNA-31的表达是健康对照组的1.64倍（P=0.02），但是平均miRNA-31增高的幅度均低于RA患者。结论表达上调的miRNA-31可能作为评估RA疾病活动的生物标记物。

Objective To investigate the expression of miRNA-31 in peripheral blood mononuclear cells （PBMCs） of rheumatoid arthritis （RA） patients, and the relationship between miRNA-31 and disease activity of RA.Methods After obtaining the informed consent, peripheral blood samples of 56 RA patients, 12 systemic lupus erythematosus （SLE） patients, 6 Sj？gren＇s syndrome （SS） patients and 30 healthy controls were collected from the Department of Rheumatology, Peking University Third Hospital. RNA was extracted from the PBMCs which were separated by Ficoll-Paque PLUS. The expression of miRNA-31 in the PBMCs of RA patients, SLE patients, SS patients and healthy controls was detected by real-time Polymerase Chain Reaction （PCR）. Furthermore, according to the RA disease activity score （DAS28）, RA patients were divided into high, moderate and low disease activity groups and remission group, and miRNA-31 expression was compared between different groups. Data were analyzed using t test or Mann-Whitney U test.Results The expression of miRNA-31 in PBMCs of RA patients was 7.25 times （P=0.003 8） higher when compared with that of the control group. To be specific, the expression of miRNA-31 was 10.63 times in PBMCs of high activity RA group （P=0.01） and 8.95 times in moderate activity RA group （P=0.000 3） when compared with that of the control group, and there was no significant difference between low activity, remission groups and control groups in terms of miRNA-31 expression. Furthermore, the expression of miRNA-31 in PBMCs of SLE patients was not significantly different from the control and miRNA-31 expression in PBMCs of SS patients was 1.64 times （P=0.02） higher than that of the RA patients, but the average level of miRNA-31 was much less than that of RA patients. The increased miRNA-31 may serve as a diagnostic marker for disease activity of RA.