结核性胸膜炎患者胸液中CD4~+ CD25~+ FoxP3~+调节T细胞抑制抗结核免疫

目的研究结核性胸膜炎患者胸液中CD4+CD25+FoxP3+调节T细胞是否增多,这些调节T细胞是否抑制结核的特异细胞免疫反应。方法使用细胞分离、流式细胞分析及体外细胞培养作细胞增殖及增殖抑制等实验方法,对15例结核性胸膜炎患者及17例健康正常人群胸液及外周血白细胞中CD4+CD25+FoxP3+调节T细胞的量及特征作研究。结果结核性胸膜炎患者胸液中CD4+CD25+FoxP3+调节T细胞明显高于患者及健康人群外周血。在体外,结核性胸膜炎患者胸液中单核细胞对BCG刺激产生γ-干扰素(IFN-γ)的能力明显强于患者及健康人群外周血中单核细胞;把这些调节T细胞从胸液单核细胞中清除,增强了结核患者胸液单核细胞对BCG刺激产生IFN-γ;从结核患者胸液分离的这些调节T细胞能抑制结核患者Th1细胞产生IFN-γ。结论结核性胸膜炎患者胸液CD4+CD25+FoxP3+调节T细胞增多,抑制结核性胸膜炎患者Th1细胞免疫反应,从而参与了结核性胸膜炎的发病。

CD4 + CD25 + FoxP3 + regulatory T cells suppressing cellular immune responses in tuberculous pleural effusion

Objective To determine whether CD4+ CD25+ FoxP3+ regulatory T cells are increased in tuberculous pleural effusion(TPE) and suppress cellular immune responses.Methods The frequency and the function of regulatory T cells from pleural fluid and blood in 15 untreated TPE patients and circulating regulatory T cells in 17 healthy control subjects were compared by using cell separation,flow cytometry analysis,proliferation assays and cytokines determination.Results The number of CD4+ CD25+ FoxP3+ regulatory T cells significantly were increased in the pleural fluid than those of peripheral blood from TPE patient and healthy control subjects.The pleural fluid mononuclear cells(PFMCs) from TPE had significantly higher IFN-γ production in response to BCG compared to peripheral blood mononuclear cells(PBMCs) from both TPE patient and healthy donors.Depletion of CD4+ CD25+ FoxP3+ regulatory T cells from PFMCs of TPE patient enhanced BCG-induced IFN-γ production.These CD4+CD25+FoxP3+regulatory T lymphocytes isolated from the pleural fluid were capable of suppressing BCG-stimulated IFN-γ production in TPE patients.Conclusions CD4+ CD25+ FoxP3+ regulatory T cells are increased in patients with TPE,suppress Th1-type immune responses and may therefore contribute to the pathogenesis of human tuberculosis.