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Updated: Jun 28, 2026
08:33
Quantitative Polymerase Chain Reaction-based Analyses of Murine Intestinal Microbiota After Oral Antibiotic Treatment
Published on: November 17, 2018
Antimicrobial host defense in the upper gastrointestinal tract
Yoshio Hosaka1, Maureen Koslowski, Sabine Nuding
1Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany.
European Journal of Gastroenterology & Hepatology
|November 8, 2008
Summary
The esophagus has strong antimicrobial peptides, but weaker antifungal defenses against Candida. This suggests unknown molecules are crucial for esophageal immunity.
Area of Science:
- Gastroenterology
- Immunology
- Microbiology
Background:
- Microbial infections are rare in the esophagus, unlike other parts of the GI tract.
- Antimicrobial host factors and mucosal activity in the upper GI tract remain incompletely understood.
Purpose of the Study:
- To systematically assess the distribution and quantity of antimicrobial host factors in the upper GI tract.
- To evaluate functional mucosal antimicrobial activity in the esophagus, stomach, and duodenum.
Main Methods:
- Biopsies from healthy esophagus, stomach, and duodenum were analyzed from 12 individuals.
- Real-time PCR quantified mRNA expression of antimicrobial peptides (defensins, cathelicidin, etc.).
- Immunostaining and antimicrobial/antifungal assays of tissue extracts were performed.
Main Results:
- Inducible beta-defensins, elafin, and psoriasin were predominantly expressed in the esophagus compared to the stomach and duodenum.
- Esophageal and stomach tissue extracts showed potent antibacterial activity against E. coli.
- Esophageal extracts exhibited weaker antifungal activity against Candida albicans.
Conclusions:
- The esophagus exhibits dominant expression of certain antimicrobial peptides but reduced potency against Candida albicans.
- These findings highlight a potential role for uncharacterized antimicrobial molecules in esophageal defense.
- Further research is needed to identify these unknown factors contributing to esophageal immunity.
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