MPO-ANCA相关性血管炎患者中性粒细胞外捕网与滤泡辅助T细胞间关系的探讨

The relationship between neutrophil extracellular net and follicular helper T cells in patients with anti-neutrophilcytoplasmic myeloperoxidase antibody-associated vasculitis and its clinicalsignificance

目的探讨抗中性粒细胞胞质髓过氧化物酶抗体相关性血管炎(MPO-AAV)患者中性粒细胞外捕网(NET)与滤泡辅助T细胞(Tfh)间关系及意义。方法选择初诊未治疗的MPO-AAV患者和健康对照者各35例,流式细胞术(FCM)检测所有受试者外周血Tfh占CD4^(+)T细胞分数(Tfh%)、表达ICOS的Tfh占CD4^(+)T细胞分数(ICOS+Tfh%)及Tfh表达ICOS的平均强度(MFI);酶联免疫吸附试验(ELISA)法检测外周血MPO-ANCA、NET及IL-23水平,收集每例受试者的临床资料,评估每例患者病情活动度(BVAS-V3)。结果与健康对照组比较,MPO-AAV组外周血Tfh%、ICOS+Tfh%、Tfh的MFI、NET及IL-23水平均高于对照组[分别为(25.7±3.9)%vs(20.7±5.3)%,P<0.001;(1.9±1.0)%vs(0.8±0.4)%,P<0.001;(59.5±10.3)vs(48.7±6.4)(MFI),P<0.001;(0.6±0.2)vs(0.2±0.1)(吸光度),P<0.001;(0.7535±0.2019)vs(0.2375±0.0870)(pg/L),P<0.001]。双变量相关性分析提示MPO-ANCA水平分别与Tfh%及Tfh的MFI呈正相关(分别为r=0.737,P<0.001;r=0.628,P<0.001),但在多变量线性回归分析显示MPO-ANCA仅与Tfh%相关(P<0.001)。IL-23分别与Tfh%、Tfh的MFI及NET水平呈正相关(分别为:r=0.475,P=0.004;r=0.359,P=0.034;r=0.806,P<0.001)。虽然双变量相关性分析提示Tfh%分别与外周血中NET及IL-23水平呈正相关(分别为:r=0.714,P<0.001;r=0.480,P=0.004),但多变量线性回归分析显示Tfh%仅与NET水平呈正相关(P<0.001),即NET是影响Tfh%的独立因素。同时,结果显示NET与肾损害间存在相关性(r=0.390,P=0.021)。结论NET可能通过激活髓样树突状细胞提升Tfh%,以辅助B细胞产生特异性自身抗体MPO-ANCA参与MPO-AAV发病。

Objective To investigate the relationship between neutrophils extracellular net(NET)and follicular helper T cells(Tfh)in patients with anti-neutrophil cytoplasmic myeloperoxidase antibody-associated vasculitis(MPO-AAV)and its significance in the pathogenesis.Methods 35 patients with untreated MPO-AAV(patient group)and 35 healthy volunteersas control(control group)were enrolled in this study.Flow cytometry(FCM)was employed to detect percentage of Tfh in CD4+T cells(Tfh%),percentage of Tfh expressing ICOS in CD4+T cells(ICOS+Tfh%)and mean intensity(MFI)of Tfh expressing ICOS in their peripheral blood,while enzyme linked immunosorbent assay(ELISA)was used to measure the level of MPO-ANCA,NET and IL-23 intheirblood.Their demographic documents were collected and the disease activity of all patients were recorded by Birmingham Vasculitis Activity Score-version 3(BVAS-V3).Results Compared with those in control group,the detected Tfh%,ICOS+Tfh%,MFI,NET and IL-23 increased[(25.7±3.9)%vs(20.7±5.3)%,P<0.001;(1.9±1.0)%vs(0.8±0.4)%,P<0.001;(59.5±10.3)vs(48.7±6.4)(MFI),P<0.001;(0.6±0.2)vs(0.2±0.1)(absorbance),P<0.001;and(0.7535±0.2019)vs(0.2375±0.0870)(pg/L),P<0.001,respectively].By bivariate correlation analysis,the MPO-ANCA had positive correlation with the Tfh%and the MFI of ICOS+Tfh(r=0.737,P<0.001;r=0.628,P<0.001,respectively),whereas,multivariate linear regression analysis indicated the MPO-ANCA only was associated with Tfh%(P<0.001).Statistical analysis also showed IL-23 was positively correlated with Tfh%,the MFI of ICOS+Tfh,and the NET(r=0.475,P=0.004;r=0.359,P=0.034;and r=0.806,P<0.001,respectively).Although the Tfh%was positively correlated with serum NET and IL-23(r=0.714,P<0.001 and r=0.480,P=0.004,respectively)by bivariate correlation analysis,multivariate linear regression analysis demonstrated that the NET levelwasthe only independent influence factor on Tfh%(P<0.001).By bivariate correlation analysis,the renal lesions had positive correlation with the NET(r=0.390,P=0.021).Conclusion To participate in the pathogenesis of MPO-AAV,NET may increase Tfh%by activating myeloid dendritic cells to assist B cells to produce specific autoantibody MPO-ANCA.