中文摘要：

目的：探讨卡介苗（BCG）刺激后,结核菌素试验阳性（PPD＋）正常人外周血单个核细胞（PBMCs）中CD8＋T细胞的活化、增殖、细胞因子产生及调节性T细胞（Treg）对其调节作用。方法：体外用BCG刺激PPD＋正常人PBMCs,检测CD8＋T细胞的细胞因子产生、活化和增殖。纯化后获得调节性T细胞（Treg）和CD25-细胞,检测Treg对CD8＋T细胞增殖的调节作用。结果：BCG诱导CD8＋T细胞表达CD69和CD25等活化分子。在低剂量IL-2存在的条件下,BCG诱导CD8＋T细胞发生增殖,且增殖的CD8＋T细胞大部分表达Granzyme-B。体外BCG短期刺激PBMCs后,CD8＋T细胞几乎不产生IFN-γ、IL-2和TNF-α。此外,调节性T细胞抑制CD8＋T细胞增殖。结论：BCG诱导CD8＋T细胞活化、增殖和表达颗粒酶,Treg抑制CD8＋T细胞增殖。

英文摘要：

Objective：To determine the activation,proliferation,cytokine production and regulation of CD8＋ T cells in PBMCs from PPD＋ individuals following stimulation with BCG.Methods：PBMCs from PPD＋ donors were stimulated with BCG,and cytokine production,activation and proliferation were assessed by flow cytometry.Regulatory effect of regulatory T cells（Treg） on proliferation of CD8＋ T cells were assessed by purified Treg and CD25-cells.Results：BCG could induce the expression of CD69 and CD25 by CD8＋ T cells and induce the proliferation of CD8＋ T cells in the presence of low dose of IL-2.The majority of proliferating CD8＋ T cells expressed Granzyme-B.However,CD8＋ T cells produced very low levels of IFN-γ,IL-2 and TNF-α following short term stimulation with BCG.Furthermore,the proliferation of CD8＋ T cells was inhibited by Treg cells.Conclusion：Our data indicates that CD8＋ T cells could be activated and induced to proliferate and produce Granzyme-B following stimulation with BCG.The proliferation of CD8＋ T cells is regulated by Treg.