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Lactobacilli Have a Niche in the Human Nose
Ilke De Boeck1, Marianne F L van den Broek1, Camille N Allonsius1
1Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
Cell Reports
|May 28, 2020
Summary
Beneficial Lactobacillus bacteria are more common in healthy upper respiratory tracts (URT) than in chronic rhinosinusitis patients. One strain, Lactobacillus casei AMBR2, adheres to URT, fights pathogens, and colonizes the nose.
Area of Science:
- Microbiology
- Human Microbiome
- Immunology
Background:
- The human gut and vaginal microbiomes have many characterized beneficial microbes.
- Beneficial microbes in the human upper respiratory tract (URT) are underexplored.
- Chronic rhinosinusitis (CRS) is a condition affecting the URT.
Purpose of the Study:
- To investigate the prevalence of beneficial microbes in the healthy URT compared to the URT of patients with CRS.
- To isolate, characterize, and explore the genetic and functional properties of URT-specific Lactobacillus strains.
- To assess the potential keystone function of specific lactobacilli in the URT habitat.
Main Methods:
- Comparative analysis of Lactobacillus prevalence in healthy URT versus CRS patient URT.
- Isolation and culturing of URT-specific Lactobacillus strains.
- Genetic characterization, including identification of catalase genes.
- Functional assays for adherence to URT epithelium, pathogen inhibition, and nasal colonization in vivo.
Main Results:
- Lactobacillus taxa are more prevalent in healthy URT than in CRS patients.
- URT-specific Lactobacillus isolates were cultured and characterized.
- Identified lactobacilli possess unique catalase genes.
- Lactobacillus casei AMBR2 demonstrated strong adherence to URT epithelium via fimbriae.
- L. casei AMBR2 inhibited URT pathogen growth and virulence.
- L. casei AMBR2 successfully colonized the nasal epithelium of healthy volunteers.
Conclusions:
- Specific Lactobacillus strains are adapted to the human upper respiratory tract.
- Lactobacillus casei AMBR2 exhibits properties suggesting a beneficial role in the URT.
- These findings highlight a potential keystone function for specific lactobacilli in maintaining URT health and preventing CRS.
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