类风湿关节炎患者血清IgG及亚类的水平和临床意义

目的探讨类风湿关节炎(RA)患者血清IgG及亚类的水平和临床意义。方法选择2018年10月至2019年6月该院风湿免疫科收治的RA患者54例纳入RA组,选择同期36例健康体检者纳入对照组。采用双抗体夹心法ELISA检测血清IgG亚类水平;采用免疫散射比浊法检测免疫球蛋白(IgG、IgA、IgM)、补体(C3、C4)和类风湿因子(RF)水平;采用流式点阵免疫发光法检测抗环瓜氨酸肽(CCP)抗体水平。比较两组各检测指标水平,分析RA患者血清IgG亚类与IgG、IgA、IgM、C3、C4、RF及抗CCP抗体之间的相关性。结果RA组血清IgG、IgA、RF和抗CCP抗体水平显著高于对照组(P<0.05),但IgM、C3和C4水平差异无统计学意义(P>0.05)。RA组血清IgG1和IgG3水平显著高于对照组(P<0.05),两组血清IgG2和IgG4水平差异无统计学意义(P>0.05)。与对照组比较,RA组IgG1/IgG和IgG3/IgG显著升高(P<0.05),而IgG2/IgG显著下降(P<0.05)。Spearman相关分析显示,RA组患者血清IgG1水平与IgG呈高度正相关(r=0.865,P<0.05);IgG2、IgG3水平与IgG均呈中度正相关(r=0.613、0.644,P<0.05);IgG4水平与IgG呈低度正相关(r=0.271,P<0.05);IgG2水平与IgA呈低度正相关(r=0.399,P<0.05);IgG3水平与IgM呈低度正相关(r=0.343,P<0.05)。IgG各亚类与RF、抗CCP抗体之间均无相关性(P>0.05)。结论RA患者血清IgG水平显著升高,并且存在IgG亚类水平变化。IgG亚类检测对RA早期诊断价值有限。

Levels and clinical significance of serum IgG and IgG subclasses in patients with rheumatoid arthritis

Objective To investigate the levels of serum IgG and IgG subclasses in the patients with rheumatoid arthritis(RA)and their clinical significances.Methods Fifty-four patients with RA treated in the department of rheumatology and immunology of the hospital from October 2018 to June 2019 were selected as the RA group and contemporaneous 36 persons undergoing healthy physical examination were selected as the healthy control group(HCs).The serum IgG subclasses levels were detected by adopting the double antibody sandwich method of enzyme-linked immunosorbent assay(ELISA).The serum immunogobulin(IgG,IgA,IgM),complement(C3,C4)and rheumatoid factor(RF)levels were detected by the adopting the immunonephelometric assay.Anti-cyclic citrullinated peptide(CCP)antibody level was detected by multiplexed bead immunoassay.The levels of detected indexes were compared between the 2 groups.The correlation of serum IgG subclasses with IgG,IgA,IgM,C3,C4,RF and anti-CCP antibody in the RA group was analyzed.Results The levels of serum IgG,IgA,RF and anti-CCP antibody in the RA group were significantly higher than those in the HCs group(P<0.05).But the levels of serum IgM,C3 and C4 had no statistical differences(P>0.05).The levels of serum IgG1 and IgG3 in the RA group were significantly higher than those in the HCs(P<0.05),and the levels of serum IgG2 and IgG4 had no statistical difference between the RA group and the HCs group(P>0.05).Compared with the HCs group,the serum IgG1/IgG and IgG3/IgG ratios in the RA group were significantly increased(P<0.05)and the serum IgG2/IgG ratio was significantly decreased(P<0.05).The Spearman correlation analysis showed that the serum IgG1 level in the RA group showed highly positive correlation with the serum IgG(r=0.865,P<0.05);the serum IgG2 and IgG3 levels had moderately positive correlation with the serum IgG(r=0.613,0.644,P<0.05)and the serum IgG4 level had lowly positive correlation with the serum IgG(r=0.271,P<0.05).The serum IgG2 level had lowly positive correlation with IgA(r=0.399,P<0.05)and the serum IgG3 level had lowly positive correlation with IgM(r=0.343,P<0.05);No correlation was found between the levels of serum IgG subclasses with the levels of RF and anti-CCP antibody(P>0.05).Conclusion The level of serum IgG in RA patients is increased significantly,and the changes of serum IgG subclasses levels exist.The detection of IgG subclasses has the limited value for the early diagnosis of RA.