【摘要】 目的:初步探讨李斯特菌溶血素(LLO)刺激呼吸道上皮细胞株(16-HEB)产生炎性反应及促进MUC5AC表达的分子机制,为阐明李斯特菌的致病机制提供理论依据。方法:采用不同浓度的LLO(15、30、45μg/ml)刺激16-HEB细胞株24 h后,qRT-PCR和ELISA法分别检测细胞中MUC5AC的mRNA转录水平与蛋白浓度变化,以及炎性因子IL-6与IL-1β的含量及mRNA转录水平; Western blot检测不同浓度LLO刺激后细胞中p-Akt、Akt的表达情况及相对含量; PI3K抑制剂LY294002预处理后检测p-Akt、Akt的表达情况,随后用LLO刺激16-HEB细胞株,并进一步检测细胞中MUC5AC与炎性因子的表达转录情况。结果:随着LLO刺激浓度的增加,细胞中MUC5AC的转录水平与浓度逐渐上升,且均显著高于对照组(P<0. 05),炎性因子IL-6与IL-1β的含量与转录水平也显著增加(P <0. 05); Western blot结果显示LLO能够激活p-Akt的表达(P<0. 05),而使用抑制剂LY294002处理后则会显著降低细胞中p-Akt的表达(P<0. 05);抑制剂处理后细胞中MUC5AC与炎性因子的表达与转录水平均出现降低,且显著低于LLO刺激组(P<0. 05)。结论:LLO能够激活PI3K/Akt信号通路进而诱导16-HEB细胞产生炎性因子IL-6、IL-1β,并促进细胞中MUC5AC的表达。更多还原

【Abstract】 Objective: Investigate the molecular mechanism of Listeriolysin O( LLO)-induced inflammatory response and MUC5 AC expression in human bronchial epithelial cells( 16-HEB),which can provide a basis for clearing the pathogenesis of Listeria monocytogenes. Methods: 16-HEB cells were stimulated with different concentrations of LLO( 15,30,45 μg/ml) for 24 h,the mRNA level and protein concentration of MUC5 AC in 16-HEB were detected by qRT-PCR and ELISA,which were also used to detected the levels of IL-6 and IL-1β. The expression and relative content of p-Akt and Akt in different concentrations of LLO were detected by Western blot. Detection the expression of p-Akt and Akt after PI3 K inhibitor LY294002 treatment,and 16-HEB cells were subsequently stimulated with LLO to detected the expression and transcription of MUC5 AC or inflammatory factors. Results: The transcription level and concentration of MUC5 AC were increased by different concentrations of LLO,which were significantly higher than the control group( P<0. 05),and the levels of inflammatory cytokines IL-6 and IL-1β also increased significantly( P<0. 05). Western blot results showed that LLO could activation the expression of p-Akt( P < 0. 05),but,which were decreased significantly after treatment with inhibitor LY294002. The expression and transcription of MUC5 AC or inflammatory cytokines were decreased after treatment with inhibitor,which were significantly lower than LLO stimulation group( P<0. 05). Conclusion: LLO can induce the production of inflammatory cytokines IL-6,IL-1β and the expression of MUC5 AC through activating the PI3 K/Akt signaling pathways in 16-HEB cells.更多还原