CD4＋CD25＋调节性T细胞在系统性硬化病患者外周血的表达和意义

The expression and significance of CD4＊CD25＋ regulatory T cells in the peripheral blood of patients with systemic sclerosis

目的研究SSc患者外周血CD4＋CD25＋调节性T细胞的表型和功能及与纤维化病变的关系。方法用流式细胞术检测ssc患者及健康对照者外周血CD4＋CD25＋调节性T细胞叉头翼状螺旋转录因子（Foxp3）、CD127、T细胞毒性相关抗原（CTLA）-4、CD69所占比例，ELISA法检测血清TGF-β1、IL-10细胞因子水平，并分析调节性T细胞与患者胸部高分辨CT（HRCT）评分、修订的Rodnan皮肤硬化评分（MRSS）和疾病活动指标的相关性。采用t检验和Pearson相关分析法进行统计学分析。结果①与健康对照组比较，SSc患者外周血CD4＋CD25＋调节性T细胞比例增加（12．9±2．4与14．9±2．2，t=2．63，P=0．012），表面表达CD69＋、CTLA-4＋比例均降低。②与健康对照组比较，SSc患者外周血CD4＋CD25＋ Foxp3＋细胞、CD4＋CD25＋CD127咖胞比例升高（分别为3．3±0．7与5．0±0．7，5．1±1．6与7．6±2．0，t=7．03，4．195；P〈0．01），但两者无明显相关性。③SSc患者血清TGF-β1水平较健康对照组降低[（86±29）ng／ml与（133±29）ng/ml，t=-5．026，P=0．000]，IL-10水平差异则无统计学意义。④SSe患者外周血CD4＋CD25＋ Foxp3＋、CD4＋CD25＋ CD127一调节性T细胞比例与胸部高分辨率CT（HRCT）评分呈正相关（分别为r=0．541，P=0．02；r=0．486，P=-0．041），与ESR、CRP无相关。CD4＋CD25＋Foxp3＋细胞比例与MRSS正相关。结论SSc患者外周血CD4＋CD25＋调节性T细胞比例增加，免疫功能改变，不同表型CD4＋CD25＋Foxp3＋,cD4＋CD25＋D127-细胞比例增高，与皮肤和肺纤维化病变正相关，相关的细胞因子TGF-β1减少，IL-10无明显改变。

Objective To study the phenotype and function of CD4 ＋CD25 ＋ Treg cells in the peripheral blood of patients with systemic sclerosis （SSc） and their relationship with fibrosis. Methods The proportion of Foxp3, CD127, CTLA-4 and CD69 on CD4＋CD25＋ Treg cells in peripheral blood were detect by flow cytometry; the levels of TGF-[3, and IL-10 in serum were detect by enzyme-linked immunosorbent assay （ELISA） in patients with SSc. The correlation between Treg cells and the score of chest HRCT, MRSS, and disease activity was analyzed. T test and Pearson correlation analysis were used for statistical analysis. Results ① Compare to the control group, the proportion of CD4＋CD25＋ Treg cells in peripheral blood of SSc patients was increased significantly（ 12.9±2.4 vs 14.9±2.2, t=2.63, P=0.012）, and the expression of CD69＋, CTLA-4＋ on CD4＋CD25＋ Treg cells was decreased significantly （P〈0.01）. ② Compare to the control group, the proportion of CIM＋CD25＋Foxp3＋ cells and CD4＋CD25＋CD127- cells in peripheral blood of SSc patients was increased significantly （respectively, 3.3±0.7 vs 5.0＋0.7, 5.1±1.6 vs 7.6：t：2.0, t=7.03, 4.195; P〈0.01 ）, but no correlation between them was detected. ③ The level of TGF-β, in the serum of the SSc patients was lower than that of the control group（86±29 vs 133±29 ng/ml, t=-5.026, P=0.000）. However, IL-IO had no significant difference between the two groups. ④ The proportion of CD4＋CD25 ＋Foxp3 ＋ cells and CD4＋CD25 ＋CD127- cells in peripheral blood of SSc patients was positively correlated with the scores of chest HRCT （respectively, r=0.541, P=0.02; r=0.486, P=0.041）, and no correlation was observed with ESR, CRP. In addition, CD4＋CD25＋Foxp3＋ ceils were associated with MRSS. Conclusion The proportion of CD4＋CD25 ＋ Treg cells in the peripheral blood of SSc patients is increased, but they alters the immune function. The different phenotypes of Treg cells of CD4＋CD25＋Foxp3＋ cells and CD4＋CD25＋CD127 ceils in peripheral blood of SSc patients are increased significantly, which changes along with skin and lung fibrosis. The associated cytokine TGF-β1 is reduced, and IL-10 is not significantly changed.