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Gastric Mucosa Quantitative Polymerase Chain Reaction Analysis for Detecting Helicobacter pylori and Antibiotic Resistance
05:23

Gastric Mucosa Quantitative Polymerase Chain Reaction Analysis for Detecting Helicobacter pylori and Antibiotic Resistance

Published on: March 7, 2025

Gastric antimicrobial peptides fail to eradicate Helicobacter pylori infection due to selective induction and

Sabine Nuding1, Michael Gersemann, Yoshio Hosaka

  • 1Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology and University of Tübingen, Stuttgart, Germany.

Plos One
|September 17, 2013
PubMed
Abstract

Insights

Helicobacter pylori colonizes the stomach by evading antimicrobial peptides. While H. pylori resists some peptides, it is susceptible to human beta-defensin 3 (HBD3) and LL37, suggesting a complex host-pathogen interaction.

Area of Science:

  • Microbiology
  • Immunology
  • Gastroenterology

Background:

  • Antimicrobial peptides (AMPs) protect mucosal surfaces from bacterial invasion.
  • Helicobacter pylori (H. pylori) successfully colonizes the gastric environment despite AMP presence.

Purpose of the Study:

  • To investigate H. pylori's evasion mechanisms against gastric antimicrobial host factors.
  • To assess the susceptibility of H. pylori to various AMPs and antiproteases.

Main Methods:

  • Real-time PCR to quantify AMP gene expression (HBD1-4, LL37, elafin) in gastric biopsies.
  • Immunostaining for HBD2 and HBD3.
  • Antimicrobial susceptibility testing using flow cytometry, bacterial growth assays, and electron microscopy.

Main Results:

  • H. pylori infection upregulated inducible defensin HBD2 and antiprotease elafin.
  • H. pylori strains showed resistance to HBD1 and elafin, minimal susceptibility to HBD2, but were effectively killed by HBD3 and LL37.
  • Despite increased HBD2, gastric extracts showed minimal H. pylori killing activity.

Conclusions:

  • Gastric H. pylori employs strategies to evade the host's antimicrobial defense shield.
  • The study supports the hypothesis of H. pylori actively circumventing host immunity for colonization.

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