系统性红斑狼疮患者CD4＋CD25＋CD127^low/-调节性T细胞中Foxp3的表达及免疫抑制功能研究

Foxp3 expression in CD4＋CD25＋CD127^low/- regulatory T cells and its immunosuppressive effect in patients with systemic lupus erythematosus

目的研究系统性红斑狼疮（SLE）外周血中调节性T细胞不同标志以及调节性T细胞在SLE发病中的作用；探讨CD127与Foxp3的相关性，明确CD127定义调节性T细胞的特异性；鉴定CD4＋CD25＋CD127＋-T淋巴细胞免疫抑制功能。方法①采用四色直接荧光素标记法和多参数流式细胞术检．测40例SLE患者（19例初发和2l例缓解）及15名健康对照外周血CD4＋CD25＋T淋巴细胞、CD4＋CD25＋CD127^low/- T淋巴细胞、CD4＋CD25＋Foxp3＋T淋巴细胞、CD4＋CD25highT淋巴细胞、CD4＋CD25“吒D127^low/- T淋巴细胞、CD4＋CD25^hig Foxp3＋T淋巴细胞以及CD4＋CD127^low/-／-Foxp3＋T淋巴细胞占CD4＋T淋巴细胞的比率，并且将7种调节性T细胞比率与外周血抗双链DNA（dsDNA）等抗体及SLE疾病活动指数（SLEDAI）评分等进行相关性分析。②以流式细胞分选术结合细胞培养技术，检测和分析3例SLE患者和4名健康人外周血中CIM＋CD25＋CD127^low/-调节性T细胞对CD4＋CD25-效应性T细胞增殖的抑制作用。采用两样本均数的t检验，重复测量的方差分析，Pearson相关与Spearman相关分析进行统计学处理。结果①SLE患者组7种调节性T细胞比率分别为（6．1±1．7）％，（3．14±1.3）％，（2．1±1．0）％，（1．6±0．3）％，（0．97±0．28）％，（0．69±0．23）％和（0．71±0．35）％。与健康对照组比较：SLE患者组前6种调节性T细胞比率均低于健康对照组（P〈0．05）。②SLE患者组：CD4＋CD25Toxp3＋、CD4＋CD25＋Foxp3＋T淋巴细胞比率与IgA呈正相关；CD4＋CD25＋CD127^low/-淋巴细胞比率与抗SSB抗体呈正相关。③SLE患者初发组和缓解组比较：SLE患者初发组7种调节性T细胞中除CD4＋CD12T^low/- Foxp3＋T淋巴细胞比率外，其余均低于缓解组（P〈0．05o④SLE患者初发组治疗前后比较：激素治疗前6种调节性T细胞比率均低于激素治疗后（P〈0．05）。⑤SLE患者初发组、缓解组和对照组中，CD4＋CD25＋T淋巴细胞及CD4＋CD25^high淋巴细胞中Foxp3的表达与CD127低表达均呈正相关。⑥SLE患者、健康人CD4＋CD25-应性T细胞的体外增殖都可以被自身CD4＋CD25＋CD127^low/-调节性T细胞所抑制，但SLE患者的抑制率明显低于健康对照。结论SLE的免疫异常可能与调节性T细胞的数量和功能缺陷有关；CD127可能代替Foxp3作为调节性T细胞特异性的表面标记物。

Objective To study the role of peripheral blood T regulatory cells （Treg） markers, as well as different Treg cells in the pathogenesis of systemic lupus erythematosus （SLE） and explore the correlation betweenCD127 and Foxp3. The immunosuppressive effect of-CD4＋CD25＋CD127^low/- T cell is explored. Methods （1） Four-color direct fluorescence-labeled and multi-parameter flow cytometry were used to detect peripheral blood CD4＋CD25＋ T cells and other Treg cells accounted for the proportion of CD4＋ T cells in 40 SLE patients （19 cases with active disease 21 cases in remission） and 15 healthy controls. Meanwhile, its correlations with anti-dsDNA antibodies among 7 groups were analyzed. （1） Flow cytometry sorting combined with cell culture were applied to detect and analyze the proliferation inhibition effect of CD4＋CD25＋CD127^low/-regulatory T cells to CD4 ＋CD25- effector T cell. Two indenpendent samples t test, ANOVA for repeated measures, Pearson＇s correlation and Spearman＇s correlation were used for statistical analysis. Results （2） The cell ratio of the 7 groups of SLE patients was （6.1-＋1.7）%, （3.1-＋1.3）%, （2.1-＋1.0）%, （1.6-＋0.3）%, （0.97-＋ 0.28 ）%, （0.69-＋0.23）% and （0.71-＋0.35 ）% respectively. In the SLE group, the proportion of the first 6 groups was lower than the control group （P〈0.05）. For CD4＋CD25＋CD127^low/- Foxp3＋, there was no difference in the two groups （P〉0.05）. （2） CD4＋CD25＋Foxp3＋, CD4CD25^higFoxp3＋ T cells and IgA ratio was positively correlated, while CD4＋CD25highCD127^low/- T cells and anti-SSB antibodies was positively correlated in SLE patients. （3） The seven group of cells, in addition to CD4＋CD127low/-Foxp3＋ T cell ratio were lower in early-onset SLE patients than those in patients at remission （P〈0.05）. （4） The cell propor-tion of the first 6 groups was lower than that of post steroid treatment （P〈0.05）. （5） Foxp3 expression of CD4＋CD25＋ T cells and CD4＋CD25high T ceils was positively correlated with low expression of CD127 in the early onset group, remission group and the control group. （6） The CD4＋CD25＋ effect T cells could be suppressed by their own CD4＋CD25＋CD127^low/- regulatory T cells in vitro, and the inhibition of SLE patients was significantly lower than controls. Conclusion The immunological abnormality of SLE may be associated with the quatity and functional defects of immune regula-tory T cells. CD127 may be a possible alternative to Foxp3 regulatory T cell-specific surface markers.