Faculty Opinions recommendation of Human and Helicobacter pylori coevolution shapes the risk of gastric disease.

Introduction: Helicobacter pylori infection is very prevalent worldwide and is associated with the progression of the gastriccarcinogenesis cascade, being one of the main risk factors for the development of gastric carcinoma. Several factors are determinant for the infection and for the development of gastric disease, including environmental factors, host genetic factors and virulence factors of the bacteria.Material and Methods: In this review, we present an overview of the current knowledge on the determinants of the infection and on the recently described molecular mechanisms of Helicobacter pylori adhesion to the gastric mucosa, as well as its possible future therapeutic application.Results: The adhesion of Helicobacter pylori to the gastric epithelium is critical for gastric pathogenesis, allowing bacterial access to nutrients and the action of bacterial virulence factors, promoting recurrence of the infection and the progression of the gastric carcinogenesis pathway.Discussion: Eradication of Helicobacter pylori infection is the best preventive strategy available against gastric cancer, mainly if it is achieved before the development of pre-neoplastic lesions. The increase in antibiotics resistance, together with the eradication failures in some patients, has promoted the development of alternative treatments.Conclusion: The new therapeutic strategies, focused on the molecular mechanism of Helicobacter pylori adhesion, are very promising; however, future studies are needed to evaluate its in vivo efficiency and toxicity.

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Helicobacter pylori patient isolates from South Africa and Nigeria differ in virulence factor pathogenicity profile and associated gastric disease outcome

Scientific Reports ◽

10.1038/s41598-020-66128-0 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Pia Palamides ◽

Tolulope Jolaiya ◽

Ayodeji Idowu ◽

Eva Loell ◽

Charles Onyekwere ◽

...

Keyword(s):

South Africa ◽

Helicobacter Pylori ◽

Virulence Factor ◽

Disease Outcome ◽

Gastric Disease

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Cag3 Is a Novel Essential Component of the Helicobacter pylori Cag Type IV Secretion System Outer Membrane Subcomplex

Journal of Bacteriology ◽

10.1128/jb.00946-09 ◽

2009 ◽

Vol 191 (23) ◽

pp. 7343-7352 ◽

Cited By ~ 38

Author(s):

Delia M. Pinto-Santini ◽

Nina R. Salama

Keyword(s):

Helicobacter Pylori ◽

Outer Membrane ◽

Protein Interactions ◽

Sequence Similarity ◽

Structural Similarity ◽

Type Iv Secretion ◽

Host Cells ◽

Gastric Disease ◽

Type Iv ◽

Steady State Levels

ABSTRACT Helicobacter pylori strains harboring the cag pathogenicity island (PAI) have been associated with more severe gastric disease in infected humans. The cag PAI encodes a type IV secretion (T4S) system required for CagA translocation into host cells as well as induction of proinflammatory cytokines, such as interleukin-8 (IL-8). cag PAI genes sharing sequence similarity with T4S components from other bacteria are essential for Cag T4S function. Other cag PAI-encoded genes are also essential for Cag T4S, but lack of sequence-based or structural similarity with genes in existing databases has precluded a functional assignment for the encoded proteins. We have studied the role of one such protein, Cag3 (HP0522), in Cag T4S and determined Cag3 subcellular localization and protein interactions. Cag3 is membrane associated and copurifies with predicted inner and outer membrane Cag T4S components that are essential for Cag T4S as well as putative accessory factors. Coimmunoprecipitation and cross-linking experiments revealed specific interactions with HpVirB7 and CagM, suggesting Cag3 is a new component of the Cag T4S outer membrane subcomplex. Finally, lack of Cag3 lowers HpVirB7 steady-state levels, further indicating Cag3 makes a subcomplex with this protein.

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Role of Interleukin-32 in Helicobacter pylori-Induced Gastric Inflammation

Infection and Immunity ◽

10.1128/iai.00637-12 ◽

2012 ◽

Vol 80 (11) ◽

pp. 3795-3803 ◽

Cited By ~ 31

Author(s):

Kosuke Sakitani ◽

Yoshihiro Hirata ◽

Yoku Hayakawa ◽

Takako Serizawa ◽

Wachiko Nakata ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Gastric Mucosa ◽

Cell Lines ◽

Inflammatory Diseases ◽

Nuclear Factor Κb ◽

Gastric Disease ◽

Ags Cells ◽

Content Type ◽

H Pylori

ABSTRACTHelicobacter pyloriinfection is associated with gastritis and gastric cancer. AnH. pylorivirulence factor, thecagpathogenicity island (PAI), is related to host cell cytokine induction and gastric inflammation. Since elucidation of the mechanisms of inflammation is important for therapy, the associations between cytokines and inflammatory diseases have been investigated vigorously. Levels of interleukin-32 (IL-32), a recently described inflammatory cytokine, are increased in various inflammatory diseases, such as rheumatoid arthritis and Crohn's disease, and in malignancies, including gastric cancer. In this report, we examined IL-32 expression in human gastric disease. We also investigated the function of IL-32 in activation of the inflammatory cytokines in gastritis. IL-32 expression paralleled human gastric tissue pathology, with low IL-32 expression inH. pylori-uninfected gastric mucosa and higher expression levels in gastritis and gastric cancer tissues.H. pyloriinfection increased IL-32 expression in human gastric epithelial cell lines.H. pylori-induced IL-32 expression was dependent on the bacterialcagPAI genes and on activation of nuclear factor κB (NF-κB). IL-32 expression induced byH. pyloriwas not detected in the supernatant of AGS cells but was found in the cytosol. Expression of theH. pylori-induced cytokines CXCL1, CXCL2, and IL-8 was decreased in IL-32-knockdown AGS cell lines compared to a control AGS cell line. We also found that NF-κB activation was decreased inH. pylori-infected IL-32-knockdown cells. These results suggest that IL-32 has important functions in the regulation of cytokine expression inH. pylori-infected gastric mucosa.

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Helicobacter pylori Adapts to Chronic Infection and Gastric Disease via pH-Responsive BabA-Mediated Adherence

Cell Host & Microbe ◽

10.1016/j.chom.2017.02.013 ◽

2017 ◽

Vol 21 (3) ◽

pp. 376-389 ◽

Cited By ~ 48

Author(s):

Jeanna A. Bugaytsova ◽

Oscar Björnham ◽

Yevgen A. Chernov ◽

Pär Gideonsson ◽

Sara Henriksson ◽

...

Keyword(s):

Helicobacter Pylori ◽

Chronic Infection ◽

Gastric Disease ◽

Ph Responsive

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Phylogeographic Origin of Helicobacter pylori Determines Host-Adaptive Responses upon Coculture with Gastric Epithelial Cells

Infection and Immunity ◽

10.1128/iai.01182-12 ◽

2013 ◽

Vol 81 (7) ◽

pp. 2468-2477 ◽

Cited By ~ 16

Author(s):

Alexander Sheh ◽

Rupesh Chaturvedi ◽

D. Scott Merrell ◽

Pelayo Correa ◽

Keith T. Wilson ◽

...

Keyword(s):

Gene Expression ◽

Gastric Cancer ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Gastric Disease ◽

Gastric Epithelial Cells ◽

Gastric Cancer Risk ◽

Content Type ◽

H Pylori ◽

Induced Apoptosis

ABSTRACTWhileHelicobacter pyloriinfects over 50% of the world's population, the mechanisms involved in the development of gastric disease are not fully understood. Bacterial, host, and environmental factors play a role in disease outcome. To investigate the role of bacterial factors inH. pyloripathogenesis, global gene expression of sixH. pyloriisolates was analyzed during coculture with gastric epithelial cells. Clustering analysis of six Colombian clinical isolates from a region with low gastric cancer risk and a region with high gastric cancer risk segregated strains based on their phylogeographic origin. One hundred forty-six genes had increased expression in European strains, while 350 genes had increased expression in African strains. Differential expression was observed in genes associated with motility, pathogenicity, and other adaptations to the host environment. European strains had greater expression of the virulence factorscagA,vacA, andbabBand were associated with increased gastric histologic lesions in patients. In AGS cells, European strains promoted significantly higher interleukin-8 (IL-8) expression than did African strains. African strains significantly induced apoptosis, whereas only one European strain significantly induced apoptosis. Our data suggest that gene expression profiles of clinical isolates can discriminate strains by phylogeographic origin and that these profiles are associated with changes in expression of the proinflammatory and protumorigenic cytokine IL-8 and levels of apoptosis in host epithelial cells. These findings support the hypothesis that bacterial factors determined by the phylogeographic origin ofH. pyloristrains may promote increased gastric disease.

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