PDF(Pubmed)
Abstract：
Impaired E-cadherin (Cdh1) functions are closely associated with cellular dedifferentiation, infiltrative tumor growth and metastasis, particularly in gastric cancer. The class-I carcinogen Helicobacter pylori (H. pylori) colonizes gastric epithelial cells and induces Cdh1 shedding, which is primarily mediated by the secreted bacterial protease high temperature requirement A (HtrA). In this study, we used human primary epithelial cell lines derived from gastroids and mucosoids from different healthy donors to investigate HtrA-mediated Cdh1 cleavage and the subsequent impact on bacterial pathogenesis in a non-neoplastic context. We found a severe impairment of Cdh1 functions by HtrA-induced ectodomain cleavage in 2D primary cells and mucosoids. Since mucosoids exhibit an intact apico-basal polarity, we investigated bacterial transmigration across the monolayer, which was partially depolarized by HtrA, as indicated by microscopy, the analyses of the transepithelial electrical resistance (TEER) and colony forming unit (cfu) assays. Finally, we investigated CagA injection and observed efficient CagA translocation and tyrosine phosphorylation in 2D primary cells and, to a lesser extent, similar effects in mucosoids. In summary, HtrA is a crucially important factor promoting the multistep pathogenesis of H. pylori in non-transformed primary gastric epithelial cells and organoid-based epithelial models.
摘要：
E-cadherin(Cdh1)功能受损与细胞去分化密切相关。浸润性肿瘤生长和转移，尤其是胃癌。I类致癌物幽门螺杆菌(H.幽门螺杆菌）定植胃上皮细胞并诱导Cdh1脱落，其主要由分泌的细菌蛋白酶高温需求A(HtrA)介导。在这项研究中,我们使用来自不同健康供体的胃组织和粘膜组织的人原代上皮细胞系来研究HtrA介导的Cdh1裂解以及随后在非肿瘤性背景下对细菌发病机理的影响。我们发现2D原代细胞和粘膜中HtrA诱导的胞外域裂解对Cdh1功能的严重损害。由于粘液体表现出完整的顶端基底极性，我们研究了细菌跨单层的迁移，它被HtrA部分去极化，如显微镜所示，跨上皮电阻（TEER）和集落形成单位（cfu）测定的分析。最后,我们研究了CagA注射，并观察到2D原代细胞中有效的CagA易位和酪氨酸磷酸化，在较小程度上，类似的效果在粘液类。总之,HtrA是促进幽门螺杆菌在未转化的原代胃上皮细胞和基于器官的上皮模型中的多步骤发病的至关重要的因素。
