CD4+CD25+FoxP3+调节T细胞抑制肺结核患者特异细胞免疫

  目的 了解结核患者外周血中CD4+CD25+FoxP3+调节T细胞在抑制结核患者结核特异细胞免疫反应中的作用。 方法 使用细胞分离、流式细胞分析、细胞增殖和细胞因子测定等方法，比较结核患者及健康正常人群外周血中CD4+CD25+FoxP3+调节T细胞的量及功能特征的差异。 结果 结核患者外周血中CD4+CD25+FoxP3+调节T细胞数占CD4+细胞总数的比例显著高于健康正常人群；在BCG及ESAT-6的刺激下，结核患者外周血单个核细胞增殖能力和产生γ-干扰素的能力比健康正常人群明显增强。在BCG刺激下，结核患者外周血CD4-细胞产生γ-干扰素(1289.62±519.01)及白介素-10(1045.40±534.12)的能力比结核患者外周血BPMCs细胞产生γ-干扰素(624.50±261.13)及白介素-10(377.00±249.56)的能力显著增强(均p<0.05)；在BCG及ESAT-6的刺激下，结核患者外周血CD4+CD25+调节T细胞显著抑制结核患者外周血CD4+CD25-细胞产生γ-干扰素及白介素-10。 结论 结核患者CD4+CD25+FoxP3+调节T细胞数量增多，抑制结核患者结核特异细胞免疫反应功能增强，可能与结核的发生、发展及转归有密切关系。

CD4+CD25+FoxP3+regulatory T cells suppress specific cellular immune responses in active pulmonary TB patients

Objective To identify whether CD4+CD25+FoxP3+regulatory T cells(Treg) are expanded in patients with active pulmonary tuberculosis(TB) and to characterize Treg functions in the modulation of antigen-specific responses. Methods The frequency and the immune function of circulating regulatory T cells were compared in the patients with active pulmonary TB and heathy control subjects using flow cytometry analysis,proliferation assays and determination of cytokines. Results The percentage of CD4+CD25+FoxP3+regulatory T cells within the total CD4 CD4+ population was significantly increased in the peripheral blood in active pulmonary TB patients than that in heathy control subjects(p<0.01).The peripheral blood mononuclear cells(PBMCs) of pulmonary TB patient had significantly higher cellular proliferation and IFN-γ production in response to both Bacille Calmette Guerin(BCG) and early secretory antigenic target-6(ESAT-6) compared to PBMCs from healthy donors(all p<0.05).In active pulmonary TB patients, the peripheral blood CD4- T cells had higher BCG-induced IFN-γ and IL-10 production (1289.62±519.01 and 1045.40±534.12, respectively) compared to PBMCs(624.50±261.13 and 377.00±249.56, respectively)(all p<0.05). These CD4+CD25+FoxP3+regulatory T lymphocytes are capable of suppressing IFN-γ and IL-10 production in response to both BCG and ESAT-6 in peripheral blood CD4+CD25- cell from TB patients. Conclusions CD4+CD25+FoxP3+ Regulatory T cells expanded in patients with active pulmonary TB may therefore contribute to the pathogensis of human TB by suppressing specific Mycobacterium tuberculosis cellular immune responses.