PD-L1信号对T细胞体外激发的调节作用

The impact of PD-L1 signal on the in vitro function of activated human T cells

目的 探讨PD L1信号在PHA体外激发体系中对人外周血T细胞的协同调节作用。方法 采用 10 μg/mlPHA刺激人外周血T细胞体外培养体系 ,加入转基因细胞PD L1/L92 9混合培养 ;免疫荧光标记和流式细胞仪分析T细胞表型及细胞周期 ;3 H TdR掺入法观察T细胞的增殖 ;ELISA法检测T细胞对IL 2和IFN γ的产生。结果 PD L1转基因细胞在PHA激发T细胞增殖的培养体系中 ,具有显著下调T细胞活化表型 ,抑制T细胞对PHA促增殖的反应性 ,这种抑制效应与其阻断T细胞于G0 /G1细胞周期及使活化T细胞分泌IL 2和IFN γ的水平下降有关。同时还发现PD L1信号能抑制PHA介导的T细胞活化诱导凋亡。结论 PD L1信号在体外PHA激发T细胞培养体系中 。

Objective To investigate PD-L1 regulatory effect on purified human T cells derived from peripheral blood stimulated with PHA. Methods Co-culture of transgenic cells PD-L1/L929 and T cells stimulated with 10μg/ml PHA, immunophenotypic analysis, 3H-TdR incorporation and quantitative measurement of IL-2 and IFN-γ were performed. Results With the stimulation of 10μg/ml PHA, transgenic cells PD-L1/L929 significantly down-regulated the stimulatory phenotype and proliferation of T cells, which resulted in arrest of T cells in phase G 0/G 1,and significantly decreased levels of IL-2 and IFN-γ secretion. Meanwhile, it was found that PD-L1 signal inhibited apoptosis of T cells stimulated with 10μg/ml PHA. Conclusion PD-L1 signal has a negatively regulatory effect on PHA-activated human T cells in vitro .