系统性红斑狼疮患者外周血CD4＋CD25highFoxp3＋调节性T细胞数量和Foxp3mRNA的表达水平与疾病活动性的相关性

The populations of CD4＋CD25highFoxp3＋ T regulatory cells, Foxp3 mRNA expression related to disease activity of systemic lupus erythematosus

目的研究系统性红斑狼疮（SEE）患者CD4＋CD25highFoxp3＋调节性T细胞的数量及其功能基因FoxD3mRNA的表达水平与SLE疾病活动性和肾脏损伤的相关性。方法采用四色流式细胞术以Foxp3-异硫氰酸荧光素（FITC）／CD2-藻红蛋白／CD4-多甲藻叶绿素蛋白（PerCP）／CD3一藻蓝蛋白7抗体组合检测40名健康对照者及42例SLE患者外周血CD4＋CD25highFoxp3＋调节性T细胞的数量，实时荧光定量聚合酶链反应（PCR）检测特异性转录因子Foxp3mRNA的表达水平，并分析其与SLE患者疾病活动指数（SLEDAI）、补体c3及血清抗双链DNA（dsDNA）抗体的关系。统计学方法采用￡检验和Spearman相关分析。结果活动期SLE患者外周血CD4＋CD25highFoxp3＋调节性T细胞数量显著低于健康对照组[（4±3）％与（7±4）％，P〈0．05]，稳定期与健康对照组差异无统计学意义（P〉0．05）；活动期SLE患者外周血CD4＋CD25highFoxp3＋调节性T细胞数量及CD4＋CD25highFoxp3＋调节性T细胞／CD4＋比值显著低于稳定期患者[（4±3）％，（9±6）％与（5±4）％，（10±6）％，P均〈0．05]；活动期SLE患者外周血Foxp3mRNA的表达水平明显低于稳定期和对照组（P〈0．01，P〈0．05）；SLE患者并发肾病组外周血CD4＋CD25highFoxp3＋调节性T细胞数量及CD4＋CD25highFoxp3＋调节性T细胞／CD4＋比值显著低于SLE非肾病组（P〈0．05）。相关分析显示，SLE患者外周血CD4＋CD25highFoxp3＋调节性T细胞数量与SLEDAI呈负相关（r=-0．5782，P〈0．05）；CD4＋CD25highFoxp3＋调节性T细胞／CD4＋比值与SLEDAI呈负相关（r=-0．4913，P〈0．05），与补体c3呈正相关（r=0．3687，P〈0．05）；SLE患者外周血CD4＋CD25highFoxp3＋调节性T细胞数量与Foxp3mRNA的表达水平呈正相关（r=0．6142，P〈0．01）。结论SLE患者外周血CD4＋CD25highFoxp3＋调节性T细胞和Foxp3mRNA的变化可能是导致SLE疾病发生和发展的关键因素之一，与疾病的活动性有密切关系。

Objective To investigate the ratios of peripheral blood CD4＋CD25highFoxp3＋ regulatory T cells of systemic lupus erythematosus （SLE） patients, and explore its association with disease activity and nepnropathy. Methods PBMC lymphocytes in 42 patientswith SLE and PBMC in 40 normal healthy donors were evaluated for the proportion of Treg cells, as a percentage of the total CD4＋ cells, by flow cytometric analysis. Levels of mRNA for Foxp3 were measured with a real-time quantitative PCR. The proportion of Treg cells and its association with SLED^I, nephropathy, serum anti-dsDNA antibody, and C3 levels were analyzed. Statistical analysis was conducted with t-test and Spearman＇s correlation analysis, Results Patients with active disease had statistically significantly lower levels of CD4＋CD25highFoxp3＋ Treg than normal controls [ （4±3）% vs （7±4）%, P〈0.05], while no significant difference could be found between patients with non- active disease and normal controls （P〉0.05）. The percentage of peripheral blood CD4＋CD25highFoxp3＋ Treg/ CD4＋ in patients with active disease was significantly lower when compared to patients with non-active disease [（9＋6）% vs （10＋6）%, P〈0.05], and it was related to the disease activity. SLE patients with nephropathy had significantly lower levels of CD4＋CD25highFoxp3＋ Treg and CD4＋CD25highFoxp3＋ Treg/CD4＋ than patientswithout nephropathy （P〈0.05）. Foxp3 mRNA levels were lower in PBMC from active disease patients than those in non-active disease. In addition, there was a negative correlation between the populatidns of CD4＋CD25highFoxp3＋ and SLEDAI （r=-0,5892, P〈0.05）. There was a negative correlati0n, between the percentage of CD4＋CD25highFoxp3＋/CD4＋ and SLEDAI （r=-0.4962, P〈0.05）, while there was a positive correlation between the percentage of CD4＋CD25highFoxp3＋/CD4＋ and C3 （r=0.3867, P〈0.05）. There was a positive correlation between th.e populations of CD4＋CD25highFoxp3＋ and Foxp3 mRNA （r=0.6142, ＇P〈0.01）. COnclusion These suggest that the decrease of CD4＋CD25highFoxp3＋ Treg and Foxp3 mRNA expression may play a crucial role in the pathogenesis of SLE.