CD4+CD25+调节性T细胞对肺结核患者特异细胞免疫的调节作用

目的　探讨调节性T细胞对结核患者特异性细胞免疫的调节作用及其在结核病发生中的意义。方法 采用免疫磁珠从健康对照和结核患者外周血单个核细胞中分离CD4⁺CD25⁺调节性T细胞,观察其对结核患者外周血免疫反应,包括细胞增殖反应和细胞因子IFN-γ及IL-10分泌的影响。结果 体外消除CD4⁺CD25⁺调节性T细胞没有显著影响健康对照PBMC对BCG抗原的增殖反应,但可以显著增强结核患者PBMC对BCG抗原的细胞增殖反应、细胞因子IFN-γ及IL-10的分泌。分离的CD4⁺CD25⁺调节性T细胞能显著抑制结核患者CD4⁺CD25^-T细胞对BCG抗原及抗-CD3的细胞增殖和细胞因子IFN-γ分泌;CD4⁺CD25⁺调节性T细胞也抑制BCG刺激的CD4⁺CD25^-T细胞IL-10的分泌,但不影响抗-CD3刺激的IL-10分泌。结论 CD4⁺CD25⁺调节性T细胞可能通过抑制结核患者特异性细胞免疫应答促进肺结核病的发生发展。

CD4+CD25+ regulatory T cell suppressed the adaptive immunity in patients with pulmonary tuberculosis

Objective To investigate the suppressive activity of CD4⁺CD25⁺ regulatory T cell on cellular immune response and its potential contribution to pathogenesis of pulmonary tuberculosis.Methods The regulatory function of CD4⁺CD25⁺T cells on cellular response including cell proliferation,cytokine IFN-γ and IL-10 production in patients with active tuberculosis was assayed through isolation of CD4⁺CD25⁺T cells from peripheral blood mononuclear cells(PBMC).Results Depletion of CD4⁺CD25⁺T cells did not increase the cellular proliferation response of PBMC from healthy donors to BCG restimulation,but did result in significant increase of BCG stimulated cell proliferation,IFN-γ and IL-10 production in patients with pulmonary tuberculosis.In addition,isolated CD4⁺CD25⁺T cells from patients with pulmonary tuberculosis significantly suppressed the cell proliferation,IFN-γ and IL-10 production of CD4⁺CD25^-T cells in response to BCG stimulation.Conclusions CD4⁺CD25⁺T cells suppressed Mycobacterium tuberculosis immunity and therefore may contribute to the pathogenesis of tuberculosis.