巨噬细胞胞外诱捕网在类风湿关节炎患者滑膜中的表达及其临床意义

Expression and clinical significance of macrophage extracellular traps in rheumatoid arthritis synovium

目的通过检测类风湿关节炎(RA)患者滑膜巨噬细胞胞外诱捕网(METs)形成情况,探讨METs在RA发病中的作用。方法收集RA及创伤手术患者的滑膜组织,采用苏木精-伊红(HE)染色检测炎症浸润情况,激光共聚焦显微镜观察巨噬细胞(F4/80^(+))的表达、巨噬细胞极化(F4/80^(+)CD86^(+),F4/80^(+)CD206^(+))情况、METs(F4/80^(+)H2A^(+))形成水平。分离滑膜细胞,用蛋白免疫印迹法检测滑膜细胞中METs瓜氨酸化组蛋白H3(CH3)及肽酰基精氨酸脱亚胺酶4(PAD4)的水平。结果与创伤手术患者比较,RA患者滑膜组织炎性浸润程度较重,炎性细胞增多,巨噬细胞总数和Ⅰ型巨噬细胞(M1)比例均显著增多(98±7.09 vs 10±1.15,0.78±0.022 vs 0.13±0.011,P<0.001),两组间M2型巨噬细胞比例差异无统计学意义(0.23±0.019 vs 0.18±0.012,P>0.05)。RA组METs形成显著高于对照组(0.65±0.023 vs 0.18±0.012,P<0.001)。蛋白免疫印迹法显示RA患者滑膜PAD4和CH3水平较创伤手术患者明显增多(0.82±0.018 vs 0.20±0.015,0.83±0.013 vs 0.40±0.012,P<0.001)。结论RA患者滑膜中巨噬细胞明显增多,且以M1型巨噬细胞为主,METs形成明显增多。

Objective To investigate the role of macrophage extracellular traps(METs)in the pathogenesis of rheumatoid arthritis(RA)by detecting the level of METs in synovium of RA patients.Methods The synovial tissues of the patients with RA and trauma surgery were collected.The inflammatory infiltration in synovium was detected by HE staining.The expression(F4/80^(+))and polarization(F4/80^(+)CD86^(+),F4/80^(+)CD206^(+))of macrophages,and the level of METs formation(F4/80^(+)H2A^(+))were observed by laser confocal microscope.The levels of citrullinated histone H3(CH3)and peptidyl arginine deiminase 4(PAD4)in synovial cells were detected by Western blotting(WB).Results Compared with the trauma surgery patients,RA patients showed more severe inflammatory infiltration in synovial tissue and increased inflammatory cells.The total number of macrophages and the proportion of typeⅠmacrophages(M1)were significantly increased(98±7.09 vs 10±1.15,0.78±0.022 vs 0.13±0.011,P<0.001).No significant difference for the proportions of typeⅡmacrophages(M2)was found between the two groups(0.23±0.019 vs 0.18±0.012,P>0.05).The formation of METs in RA group was significantly higher than that in control group(0.65±0.023 vs 0.18±0.012,P<0.001).Western blotting showed that the levels of PAD4 and CH3 in RA group were significantly higher than those in trauma surgery patients(0.82±0.018 vs 0.20±0.015,0.83±0.013 vs 0.40±0.012,P<0.001).Conclusion Macrophages in the synovium of RA patients were significantly increased,and M1 type macrophages should be the predominant cells.The formation of METs significantly increased in RA.