Rose F, Zeller S A, Chakraborty T, Domann E, Machleidt T, Kronke M, Seeger W, Grimminger F, Sibelius U
Department of Internal Medicine, Justus Liebig University, Giessen, Germany.
Infect Immun. 2001 Feb;69(2):897-905. doi: 10.1128/IAI.69.2.897-905.2001.
The interaction of Listeria monocytogenes with endothelial cells represents a crucial step in the pathogenesis of listeriosis. Incubation of human umbilical vein endothelial cells (HUVEC) with wild-type L. monocytogenes (EGD) provoked immediate strong NO synthesis, attributable to listerial presentation of listeriolysin O (LLO), as the NO release was missed upon employment of a deletion mutant for LLO (EGD hly mutant) and was reproduced by purified LLO. Studies of conditions lacking extracellular Ca(2+) suggested LLO-elicited Ca(2+) flux as the underlying mechanism. In addition, HUVEC incubation with EGD turned out to be a potent stimulus for sustained (>12-h) upregulation of proinflammatory cytokine generation (interleukin 6 [IL-6], IL-8, and granulocyte-macrophage colony-stimulating factor). Use of deletion mutants for LLO (EGD hly mutant), listerial phosphatidylinositol-specific phospholipase C (EGD plcA mutant), broad-spectrum phospholipase C (EGD plcB mutant) and internalin B (EGD inlB mutant), as well as purified LLO, identified LLO as largely responsible for the cytokine response. Endothelial cells responded with diacylglycerole and ceramide generation as well as nuclear translocation of NF-kappa B to the stimulation with the LLO-producing strains EGD and Listeria innocua. The endothelial PC-phospholipase C inhibitor tricyclodecan-9-yl-xanthogenate as well as two independent inhibitors of NF-kappa B activation, pyrolidine dithiocarbamate and caffeic acid phenethyl ester, suppressed both the NF-kappa B translocation and the upregulation of cytokine synthesis. We conclude that L. monocytogenes is a potent stimulus of NO release and sustained upregulation of proinflammatory cytokine synthesis in human endothelial cells, both events being largely attributable to LLO presentation. LLO-induced transmembrane Ca(2+) flux as well as a sequence of endothelial phospholipase activation and the appearance of diacylglycerole, ceramide, and NF-kappa B are suggested as underlying host signaling events. These endothelial responses to L. monocytogenes may well contribute to the pathogenic sequelae in severe listerial infection and sepsis.
单核细胞增生李斯特菌与内皮细胞的相互作用是李斯特菌病发病机制中的关键步骤。用人脐静脉内皮细胞（HUVEC）与野生型单核细胞增生李斯特菌（EGD）孵育会立即引发强烈的一氧化氮（NO）合成，这归因于李斯特菌溶血素O（LLO）的李斯特菌呈现，因为使用LLO缺失突变体（EGD hly突变体）时未观察到NO释放，而纯化的LLO可重现该现象。缺乏细胞外Ca(2+)条件下的研究表明，LLO引发的Ca(2+)通量是潜在机制。此外，用EGD孵育HUVEC被证明是持续（>12小时）上调促炎细胞因子生成（白细胞介素6 [IL-6]、IL-8和粒细胞-巨噬细胞集落刺激因子）的有效刺激。使用LLO缺失突变体（EGD hly突变体）、李斯特菌磷脂酰肌醇特异性磷脂酶C（EGD plcA突变体）、广谱磷脂酶C（EGD plcB突变体）和内化素B（EGD inlB突变体）以及纯化的LLO，确定LLO在很大程度上负责细胞因子反应。内皮细胞对产生LLO的菌株EGD和无害李斯特菌的刺激反应为二酰甘油和神经酰胺生成以及核因子κB的核转位。内皮PC-磷脂酶C抑制剂三环癸烷-9-基-黄原酸酯以及两种独立的核因子κB激活抑制剂，吡咯烷二硫代氨基甲酸盐和咖啡酸苯乙酯，抑制了核因子κB转位和细胞因子合成的上调。我们得出结论，单核细胞增生李斯特菌是人类内皮细胞中NO释放和促炎细胞因子合成持续上调的有效刺激物，这两个事件在很大程度上归因于LLO呈现。LLO诱导的跨膜Ca(2+)通量以及一系列内皮磷脂酶激活以及二酰甘油、神经酰胺和核因子κB的出现被认为是潜在的宿主信号事件。这些内皮细胞对单核细胞增生李斯特菌的反应很可能导致严重李斯特菌感染和败血症中的致病后遗症。
