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Helicobacter pylori-Induced TLR9 Activation and Injury Are Associated With the Virulence-Associated Adhesin HopQ.

ABSTRACT: Helicobacter pylori is the strongest risk factor for gastric adenocarcinoma. The H. pylori cancer-associated cag pathogenicity island (cag-PAI) encodes a type IV secretion system (T4SS), which translocates microbial DNA and activates TLR9; however, most cag-PAI+-infected persons do not develop cancer and cag-PAI-independent regulators of pathogenesis, including strain-specific adhesins, remain understudied. We defined the relationships between H. pylori HopQ adhesin allelic type, gastric injury, and TLR9 activation. Type I hopQ alleles were significantly associated with magnitude of injury, cag-T4SS function, and TLR9 activation. Genetic deletion of hopQ significantly decreased H. pylori-induced TLR9 activation, implicating this adhesin in H. pylori-mediated disease.

SUBMITTER: Dooyema SDR

PROVIDER: S-EPMC8280490 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Helicobacter pylori-Induced TLR9 Activation and Injury Are Associated With the Virulence-Associated Adhesin HopQ.

Dooyema Samuel D R SDR Krishna Uma S US Loh John T JT Suarez Giovanni G Cover Timothy L TL Peek Richard M RM

The Journal of infectious diseases 20210701 2

Helicobacter pylori is the strongest risk factor for gastric adenocarcinoma. The H. pylori cancer-associated cag pathogenicity island (cag-PAI) encodes a type IV secretion system (T4SS), which translocates microbial DNA and activates TLR9; however, most cag-PAI+-infected persons do not develop cancer and cag-PAI-independent regulators of pathogenesis, including strain-specific adhesins, remain understudied. We defined the relationships between H. pylori HopQ adhesin allelic type, gastric injury, ...[more]

PMID: 33245103

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