浆细胞样树突状细胞、干扰素α、调节性T细胞在Graves病中免疫致病机制的研究

目的：探讨浆细胞样树突状细胞（pDC）、干扰素α（IFN-α）及CD4^＋CD25^＋调节性T细胞（Treg细胞）在Graves病（GD）中的免疫致病机制。方法：收集GD患者及正常对照者的外周血及甲状腺组织,利用实时PCR、免疫组化、流式细胞仪、细胞分选及纯化等技术对组织或体外实验中的细胞数目、mRNA水平或蛋白水平进行分析比较。结果：GD患者中外周血血清IFN-α水平升高,分泌IFN-α的pDC亚群细胞数目增加;IFN-α还可以诱导甲状腺细胞表达IFN-α诱导基因（IFIGs）、人类白细胞抗原（HLA）-DR基因和促甲状腺激素受体（TSHR）基因的mRNA;GD患者外周血中Treg细胞比例降低;DC使Treg细胞更易凋亡。结论：GD的发病与pDC比例增多、IFN-α水平升高以及Treg细胞比例下降等多种免疫调节因素相关。

Plasmacytoid dendritic cells,interferon-α and CD4+CD25+regulatory T ceils in immunopathogenic mechanism of Graves disease

Objective To investigate the role of plasmacytoid dendritic cells（pDCs）,interferon-α（IFN-α） and CD4^＋ CD25^＋ regulatory T cells（Treg cells） in the immunopathogenic mechanism of Graves disease.Methods Peripheral blood and thyroid tissue specimen were collected from patients with Graves disease and normal healthy controls.Real-time PCR,immunohistochemistry,flow cytometric analysis,cell isolation and purification were used to assess the number of cells,mRNA expression and protein levels,and the data collected were analyzed.Results Level of IFN-α in peripheral blood was increased and the number of IFN-α secreting pDCs subset of DCs were increased in patients with Graves disease;IFN-α could induce the mRNA expressions of interferon inducible genes（IFIGs）,human leacocyte antrigen（HLA）-DR gene and thyroid stimulating hormone receptor（TSHR） gene;the proportion of CD4^＋CD25^＋ forkhead box P3（FOXP3）^＋ Treg cells in peripheral blood was decreased in patients with Graves disease and pDCs making the Treg cells more susceptible to apoptosis.Conclusions The development of Grave disease had correlation with high proportion of pDCs,increase of IFNα and decrease of CD4^＋CD25^＋ Treg cells in its immunopathogenic mechanism.