强直性脊柱炎患者外周血CD4+CD25+调节性T细胞的研究

目的 观察强直性脊柱炎(AS)患者外周血CD4+CD25调节性T细胞(Treg)的数量、功能及肿瘤坏死因子(TNF)-a 抑制剂治疗的影响.方法 活动性AS患者25例,10例给予etanercept治疗12周,健康对照21名,分离外周血单个核细胞(PBMC),流式细胞术检测CD4+CD25high T细胞比例;实时定量聚合酶链反应检测FOXP3 mRNA表达;免疫磁珠法去除CD25+细胞,可溶性噻唑盐(WST-1)法检测T细胞增殖.结果 活动性AS组CD4+CD25high T细胞比例与对照组差异尤统计学意义,但FOXP3 mRNA表达明显低于对照组(P＜0.01),并与C反应蛋白(CRP)呈负相关(P＜0.01).两组的CD4+CD25+细胞体外均能抑制T细胞增殖(P均＜0.01). Etanercept治疗明显增加CD4+CD25highT细胞比例和FOXP3 mRNA表达(P均＜0.01),与CRP降低呈负相关(P＜0.05;P＜0.01).结论 AS患者外周血表达FOXP3的CD4+CD25+Treg细胞异常,可能参与AS发生和发展;Etanercept治疗上调Treg细胞,可能是抗TNF-α治疗的一个机制.

CD4+CD25+ regulatory T cells in peripheral blood of patients with ankylosing spondylitis

Objective To characterize and quantify the CD4 +CD25 + regulatory T (Treg) cell population in peripheral blood of patients with ankylosing spondylitis (AS) and to determine the influence of treatment with tumor necrosis factor (TNF)-a inhibitors on them.Methods Peripheral blood mononuclear cells (PBMC) were isolated from 25 patients with active AS,in which 10 patients were treated with 12 weeks of etanercept,and 21 healthy subjects.CD4+CD25high T cells were analyzed using flow cytometry,and mRNA expression of FOXP3 was determined by real-time polymerase chain reaction (PCR).Proliferation of T cells to PHA was measured by WST-1 assay using depleted CD25+ cells by immunomagnetic sorting.Results There was no significant difference in the percentage of CD4+CD25high cells in peripheral blood between patients with active AS and controls (P＞0.05).However,PBMC from patients with active AS expressed reduced levels of FOXP3 mRNA (P＜0.01) which were inversely correlated with C-reactive protein (CRP)(P＜0.01).CD4+CD25+ cells in peripheral blood of both active AS patients and controls exhibited suppressive capacity on the proliferation of effector T cells in vitro (both P＜0.01).Treatment with etanereept increased significantly CD4+CD25high cells and FOXP3 mRNA expression (both P＜0.01),with negative correlations between these increases and decrease in CRP levels (P＜0.05 and P＜0.01,respectively).Conclusion In AS patients,peripheral FOXP3-expressing CD4 +CD25 + Treg cells are abnormal,and are up-regulated by etanercept treatment.This suggests a possible pathogenesis of AS and a potential mechanism for clinical efficacy of TNF-α inhibitors.