强直性脊柱炎患者外周血单个核细胞的组蛋白甲基化

The histone methylation in peripheral blood mononuclear cells of ankylosing spondylitis patients

目的探讨强直性脊柱炎(AS)患者外周血单个核细胞(PBMC)组蛋白修饰情况。方法收集27例AS患者及22例健康对照者的静脉血;分离PBMC,采用H3K4、H3K9甲基化检测试剂盒提取组蛋白和检测H3K4、H3K9甲基化水平;半定量PCR法检测AS患者的PBMC组蛋白甲基转移酶基因(SET1、SUV39H1和SUV39H2)的mRNA表达水平;ELISA分析外周血白细胞介素(IL)-23、IL-17和肿瘤坏死因子-α(TNF-α)蛋白表达水平。结果与健康对照者比较,AS患者PBMC组蛋白H3K4甲基化水平显著升高(P<0.05),而两者组蛋白H3K9甲基化水平比较差异无统计学意义(P>0.05);半定量PCR结果显示AS患者PBMC的SET1和SUV39H1基因表达水平分别是健康对照者的1.73和0.68倍(P<0.05),而两者PBMC的SUV39H2基因的表达水平比较差异无统计学意义(P>0.05);AS患者中IL-23、IL-17、TNF-α的蛋白表达水平显著高于健康对照者(P<0.05,P<0.01);AS患者PBMC组蛋白H3K4甲基化水平与血清中IL-23、IL-17和TNF-α蛋白表达水平均呈正相关(P<0.05)。结论 AS患者外周血PBMC组蛋白甲基化呈现异常,且与AS发生发展有一定的相关性。

Objective To study the histone methylation patterns in peripheral blood mononuclear cells （PBMCs） from ankylosing spondylitis （AS） patients. Methods PBMCs from 27 AS patients and 22 healthy controls were recrui-ted. The global H3K4, H3K9 methylation was determined by assay kit. The differential expressions of the histone methyl-transferases （SETI, SUV39HI and SUV39H2） were measured by semi-quantitative RT-PCR. Protein expression levels of IL - 23, IL - 17 and TNF - α in PBMCs were determined by ELISA assay kit. Results Increased global H3K4 methyl-ation was observed in PBMCs of AS patients compared with controls （ P 〈 0. 05 ）, but not in global H3K9 methylation （ P 〉 0. 05 ）. The mRNA levels of gene SET1 and SUV39H1 in PBMCs of AS patients compared with healthy controls were 1.73 and 0. 68 folds, respectively, with significant differences （P 〈 0. 05） ; but there was no significant difference in mR-NA level of gene SUV39H2 between the two groups （P 〉 0. 05 ）. The protein expression of IL-23, IL - 17 and TNF - α in PBMCs of AS patients were significantly higher than those of controls （P 〈 0. 01, P 〈 0. 05 ）. In AS patients, global histone H3K4 methylation was significantly positively correlated to the serum protein levels of IL - 23, IL - 17 and TNF - α （P 〈 0. 05）. Conclusion Histone methylation appears abnormal in PBMCs of AS patients, which may correlates with the pathogenesis of AS.