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Published in: Journal of Clinical Immunology 1/2011

01-02-2011

Differential Effects of Multiplicity of Infection on Helicobacter pylori-Induced Signaling Pathways and Interleukin-8 Gene Transcription

Authors: Birgit Ritter, Petra Kilian, Marc Rene Reboll, Klaus Resch, Johanna Kay DiStefano, Ronald Frank, Winfried Beil, Mahtab Nourbakhsh

Published in: Journal of Clinical Immunology | Issue 1/2011

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Abstract

Interleukin-8 (IL-8) plays a central role in the pathogenesis of Helicobacter pylori infection. We used four different H. pylori strains isolated from patients with gastritis or duodenal ulcer disease to examine their differential effects on signaling pathways and IL-8 gene response in gastric epithelial cells. IL-8 mRNA level is elevated in response to high (100) multiplicity of infection (MOI) independent of cagA, vacA, and dupA gene characteristics. By lower MOIs (1 or 10), only cagA + strains significantly induce IL-8 gene expression. This is based on differential regulation of IL-8 promoter activity. Analysis of intracellular signaling pathways indicates that H. pylori clinical isolates induce IL-8 gene transcription through NF-κB p65, but by a MOI-dependent differential activation of MAPK pathways. Thus, the major virulence factors of H. pylori CagA, VacA, and DupA might play a minor role in the level of IL-8 gene response to a high bacterial load.
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Metadata
Title
Differential Effects of Multiplicity of Infection on Helicobacter pylori-Induced Signaling Pathways and Interleukin-8 Gene Transcription
Authors
Birgit Ritter
Petra Kilian
Marc Rene Reboll
Klaus Resch
Johanna Kay DiStefano
Ronald Frank
Winfried Beil
Mahtab Nourbakhsh
Publication date
01-02-2011
Publisher
Springer US
Published in
Journal of Clinical Immunology / Issue 1/2011
Print ISSN: 0271-9142
Electronic ISSN: 1573-2592
DOI
https://doi.org/10.1007/s10875-010-9467-5

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