目的了解RA患者PBMCs中差异表达的微小RNA(miRNAs,miR),探讨RA患者PBMCs中miR-155表达与RA的相关性,并了解炎症因子对miR-155表达水平的作用。方法①提取RA患者及健康对照各5例PBMCs总RNA。通过微阵列芯片技术分析miRNAs表达谱。②在芯片检测结果基础上,选择与免疫调节功能密切相关的miR-155,利用实时荧光定量(RT)-PCR测定26例RA患者和23名健康对照者的PBMC中miR-155的表达水平。③评价miR-155的表达水平与RA患者临床及实验室指标的相关性。④利用RT-PCR测定在TNF-α,IFN-γ和脂多糖刺激下miR-155表达水平的变化。采用独立样本t检验,配对t检验,F检验以及Spearman相关分析进行统计学处理。结果①miRNAs微阵列芯片表达谱提示RA患者PBMC中有14种miRNAs信号强度差别在2倍以上,其中miR-155高表达(t=9.218,P=0.001)。②miR-155的表达与血浆CRP的水平呈正相关(r=0.57,P=0.002)。③在TNF.d刺激RA患者PBMCs12、24、48h时,miR-155的表达上调,分别为11.1±4.0、2.5±1.6(t=-8.53,P〈0.01);9.5±3.6、2.5±1.6(t=-8.042,P〈0.001);8.3±3.0、2.5±1.6(t=-8.416,P〈0.001)。IFN-γ刺激12、24、48h时,miR-155的表达上调,分别为27.5±15.0、4.6±2.8(t=-4.613,P=0.006);23.8±11.1、4.6±2.8(t=-5.678,P=0.002);19.8±10.0、4.6±2.8(t=-5.118,P=0.004)。脂多糖刺激12、24、48h时,miR-155表达水平亦显著上调,分别为11.4±6.3、3.8±2.1(t=-4.285,P=0.008);9.6±5.0、3.8±2.1(t=-4.495,P=0.006);7.9±4.0、3.8±2.1(t=-4.771,P=0.005)。结论RA患者PBMCs中miR-155的表达上调与炎症因子诱导相关,可能参与了RA发病过程的调节。
Objective (1) To Screen for the miRNAs differently expressed in the peripheral blood mono-nuclear ceils (PBMCs) of rheumatoid arthritis (RA) by microarray experiments. (2) To further evaluate the expression of miR-155 in PBMCs of RA. (3) To determine the relevance between the expression of miR-155 and clinical as well as laboratory features. (4) To test whether inflammatory mediators can induce miR-155 expression in PBMCs of RA. Methods (1) Total RNA was isolated from peripheral blood mononuclear cells obtained from 5 patients of RA and 5 normal controls. Expression profiling of miRNAs was performed in a microarray analysis. (2) MiR-155 was identified for further study by stem-loop real-time RT-PCR based on SYBR-Green. PBMC from 26 patients of RA and 23 normal controls were collected. (3) Association between miR-155 and the clinical and laboratory features of RA was evaluated. (4)Induction of miR-155 following stimulation with TNF-α, IFN-γ and LPS of cultures of RA PBMCs was examined by real-time RT-PCR. Statistical analysis was done with student's t test, paired t test, and ANOVA, Spearman correlation. Results (1) Expression profiling of miRNAs revealed significant differential expression of 14 miRNAs, of which signal intensity changed over two times. MiR-155 was up-regulated in PBMCs of RA than in normal controls (t=9.218, P=0.001). (2) The expression level of miR-155 had a positive correlation with serum CRP level (r=0.57, P= 0.002). (3) Expression of miR-155 was markedly up-regulated in PBMCs of RA after stimulated with TNF-α, IFN-γ and LPS, especially with TNF-α. Conclusions The expression of miR-155 is induced by stimulating with TNF-α, IFN-γand LPS. MiR-155 may be a regulator in RA pathogenesis. Further studies are required to elucidate the function of miR-155.