类风湿关节炎患者Treg细胞变化及与病情活动度的关系

Association of circulating Treg cells with disease activity in patients with rheumatoid arthritis

目的探讨Treg细胞在类风湿关节炎(RA)患者外周血中的变化及与病情活动度、RA相关抗体的关系。方法流式细胞仪技术检测40例RA患者和40例健康对照者外周血Treg占CD4+T细胞的百分率,酶联免疫吸附试验检测血清IL-10及TGF-β1,实时荧光定量PCR法检测Foxp3 mRNA,分析Treg细胞百分率与病情活动度及RA相关抗体的相关性。结果 RA患者外周血中Treg细胞(CD4+CD25+FOXP3+T细胞)的百分率显著低于健康对照组[(5.36±1.55)%vs(7.49±1.46)%,P<0.01],Foxp3mRNA表达也较对照组显著减少(P<0.01);RA组IL-10水平低于健康对照组(P=0.000),而TGF-β1则显著高于健康对照组(P=0.000);相关性分析显示IL-10水平与Treg细胞百分率及Foxp3 mRNA相对表达量正相关;RA患者外周血中Treg细胞百分率与关节压痛数、关节肿胀数、患者疼痛模拟视觉评分、健康评估问卷、DAS28评分、红细胞沉降率、C反应蛋白等临床和实验室病情活动指标无明显相关性(P>0.05),与RF、抗CCP抗体滴度也无相关性(P>0.05)。结论 RA患者中Treg细胞数量减少并存在功能异常,疾病活动度越高的患者可能Treg细胞数量减少越明显。

Objective To investigate the changes in the circulating levels of Treg cells in patients with rheumatoid arthritis （RA） and their associations with the disease activity. Methods The fraction of circulating CD4＋CD25＋FOXP3＋ Treg cells in 40 active RA patients and 40 healthy controls were determined by flow cytometry. The serum levels of interleukin-10 （IL-10） and transforming growth factor-β1 （TGF-β1） were measured using enzyme-linked immunosorbent assay, and the expression of Foxp3 mRNA was detected with real-time PCR. The correlation of the changes in the fraction of Treg cells and the disease activity of RA was analyzed. Results RA patients showed a significantly lower level of circulating Treg cells than the control subjects [ （5.36±1.55）% vs （7.49±1.46）%, P〈0.01]. The expression of Foxp3 mRNA （P〈0.01） and serum IL-10 level （P=0.000） were significantly lower, whereas TGF-β1 significantly higher （P=0.000） in RA patients than in the controls. Spearman analysis showed that serum level of IL-10 but not TGF-β1 was correlated to the fraction of Treg ceils and Foxp3 mRNA expression, but the fraction of Treg cells was not correlated to such indices of disease activity as tender joint counts, swollen joint counts, visual analog scale, HAQ, disease activity score in 28 joints, ESR, or CRP, nor to RA self-antibodies （including RF and anti-CCP antibodies）. Conclusion A lower fraction and dysfunction of circulating Treg cells might be involved in the pathologies of RA, and a higher disease activity is associated with a greater reduction of Treg cells.