CD4~+CD25~+调节性T细胞在自身免疫性甲状腺疾病中数量和功能变化

目的:探讨自身免疫性甲状腺疾病患者外周血中CD4+CD25+调节性T细胞(Tregs)的数量和功能变化。方法:采用化学发光法测定20例初发Graves’病人、20例初发桥本甲状腺炎(HT)患者及20例健康体检者血清中促甲状腺素(TSH)、总三碘甲状腺原氨酸(TT3)、总甲状腺素(TT4)、甲状腺球蛋白抗体(TgAb)和甲状腺过氧化酶抗体(TPOAb)的水平;用流式细胞仪分析外周血单个核细胞(PBMC)中CD4+T细胞及CD4+CD25+Tregs的数量;采用磁珠分选技术分选5例HT病人和5例健康体检者PBMC中CD4+CD25+Tregs和CD4+CD25-T细胞,采用MTT法检测CD4+CD25+Tregs对自身CD4+CD25-T细胞增殖的抑制作用;提取各组PBMC的总RNA,经Real time-PCR检测TGFβ-1、Foxp3 mRNA的表达水平。结果:流式细胞检测结果显示,初发Graves’病人、初发HT患者外周血PBMC中CD4+T细胞数量与正常人比较无差异(P<0.05);初发HT患者外周血PBMC中CD4+CD25+Tregs占CD4+T细胞的比率为(1.55%±0.49%),明显低于正常对照组(2.86%±1.04%)(P<0.05);初发Graves’病人外周血PBMC中CD4+CD25+Tregs占CD4+T细胞的比率为(3.25%±0.97%),与正常对照组(2.86%±1.04%)相比无显著性差异(P<0.05)。MTT结果显示,初发HT患者CD4+CD25+Tregs对自身CD4+CD25-T细胞增殖的抑制百分率为15.7%±5.36%,与正常组(41.7%±9.87%)相比显著降低(P<0.05)。Real time-PCR结果显示,初发Graves’病人、初发HT患者PBMC的TGFβ-1 mRNA表达水平分别为(0.37±0.10)和(0.43±0.09),均明显低于正常对照组(1.02±0.04)(P<0.05);初发Graves’病人、初发HT患者PBMC的Foxp3 mRNA表达水平分别为0.62±0.09和0.42±0.29,均明显低于正常对照组(0.99±0.17)(P<0.05)。结论:本研究结果提示,HT患者外周血中CD4+CD25+Tregs的数量和功能明显降低。Graves’病和HT患者外周血PBMC中TGFβ-1、Foxp3 mRNA表达水平明显降低。

The frequency and function of CD4+CD25+ regulatory T cells in autoimmune thyroid diseases

Objective:The aim of this study is to explore the frequency and the function of circulating CD4+CD25+ regulatory T cells(Tregs) in the patients with autoimmune thyroid diseases(AITD).Methods:The serum levels of thyroid stimulating hormone(TSH),total triiodothyronine(TT3),total thyroxine(TT4),thyroglobulin antibody(TgAb) and thyroid peroxidase antibody(TPOAb) were measured with commercial electrochemiluminescence(ECL) Kits.20 patients of Graves' disease(GD) patients and 20 Hashimoto's thyroiditis(HT) were en...