title: Helicobacter pylori Outer Membrane Protein 18 (Hp1125) Is Involved in Persistent Colonization by Evading Interferon- γ Signaling.
abstract: Outer membrane proteins (OMPs) can induce an immune response. Omp18 (HP1125) of H. pylori is a powerful antigen that can induce significant interferon-γ (IFN-γ) levels. Previous studies have suggested that IFN-γ plays an important role in H. pylori clearance. However, H. pylori has multiple mechanisms to avoid host immune surveillance for persistent colonization. We generated an omp18 mutant (H. pylori 26695 and H. pylori SS1) strain to examine whether Omp18 interacts with IFN-γ and is involved in H. pylori colonization. qRT-PCR revealed that IFN-γ induced Omp18 expression. qRT-PCR and western blot analysis revealed reduced expressions of virulence factors CagA and NapA in H. pylori 26695 with IFN-γ treatment, but they were induced in the Δomp18 strain. In C57BL/6 mice infected with H. pylori SS1 and the Δomp18 strain, the Δomp18 strain conferred defective colonization and activated a stronger inflammatory response. Signal transducer phosphorylation and transcription 1 (STAT1) activator was downregulated by the wild-type strain but not the Δomp18 strain in IFN-γ-treated macrophages. Furthermore, Δomp18 strain survival rates were poor in macrophages compared to the wild-type strain. We concluded that H. pylori Omp18 has an important function influencing IFN-γ-mediated immune response to participate in persistent colonization.
authors.affiliation: Department of Microbiology, Key Laboratory for Experimental Teratology, Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong 250012, China.
authors.forename: Yuqun
authors.identifier: 0000-0002-0514-3233
authors.initials: Y
authors.lastname: Shan
authors.affiliation: Department of Microbiology, Key Laboratory for Experimental Teratology, Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong 250012, China.
authors.forename: Xingxiao
authors.initials: X
authors.lastname: Lu
authors.affiliation: Department of Microbiology, Key Laboratory for Experimental Teratology, Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong 250012, China.
authors.forename: Yingnan
authors.initials: Y
authors.lastname: Han
authors.affiliation: Shandong Center for Disease Control and Prevention, Jinan 250010, China.
authors.forename: Xinpeng
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Microbiology, Key Laboratory for Experimental Teratology, Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong 250012, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
authors.affiliation: Clinical Laboratory, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250012, China.
authors.forename: Chunhong
authors.initials: C
authors.lastname: Shao
authors.affiliation: Institute of Pharmacology, School of Medicine, Shandong University, Jinan, Shandong 250012, China.
authors.forename: Lixiang
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Microbiology, Key Laboratory for Experimental Teratology, Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong 250012, China.
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Microbiology, Key Laboratory for Experimental Teratology, Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong 250012, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Tang
authors.affiliation: Department of Microbiology, Key Laboratory for Experimental Teratology, Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong 250012, China.
authors.forename: Yundong
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Microbiology, Key Laboratory for Experimental Teratology, Chinese Ministry of Education, School of Medicine, Shandong University, Jinan, Shandong 250012, China.
authors.forename: Jihui
authors.initials: J
authors.lastname: Jia
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000096:biosynthesis / Q000235:genetics*; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D016481:Helicobacter Infections / Q000235:genetics* / Q000382:microbiology; D016480:Helicobacter pylori / Q000235:genetics / Q000254:growth & development* / Q000472:pathogenicity; D006801:Humans; D007113:Immunity, Innate / Q000235:genetics; D007371:Interferon-gamma / Q000008:administration & dosage / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D050794:STAT1 Transcription Factor / Q000096:biosynthesis; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; C000604475:Omp18 protein, Helicobacter pylori; D050794:STAT1 Transcription Factor; C494080:Stat1 protein, mouse; C080866:cagA protein, Helicobacter pylori; C092412:neutrophil-activating protein A, Helicobacter pylori; D007371:Interferon-gamma