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Updated: Sep 1, 2025
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Production and Visualization of Bacterial Spheroplasts and Protoplasts to Characterize Antimicrobial Peptide Localization
Published on: August 11, 2018
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Antimicrobial peptides: Defending the mucosal epithelial barrier
Karen F Johnstone1, Mark C Herzberg1
1Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN, United States.
Frontiers in Oral Health
|August 18, 2022
Summary
Antimicrobial proteins and peptides (AMPs), like defensins and calprotectin, are crucial for the epithelial barrier. These AMPs work together to protect against infections by inhibiting microbial growth and activating immune responses.
Area of Science:
- Immunology
- Microbiology
- Biochemistry
Background:
- The epithelial barrier is vital for defense against pathogens, as highlighted by recent viral epidemics.
- Antimicrobial proteins and peptides (AMPs) are essential components of the innate immune system, protecting epithelial surfaces.
- AMPs have evolved to maintain host-microbe homeostasis, favoring commensals over pathogens.
Purpose of the Study:
- To review the cooperative roles of defensins and calprotectin in fortifying the epithelial barrier.
- To explore the distinct and overlapping mechanisms of action of these AMPs.
- To highlight their contribution to innate immunity and protection against various infections.
Main Methods:
- Literature review focusing on defensins and calprotectin.
- Analysis of experimental models in mice (candidiasis, periodontitis).
- Examination of human innate immunity examples (neonatal sepsis).
Main Results:
- Defensins and calprotectin exhibit a broad, overlapping antimicrobial spectrum.
- Experimental models demonstrate their importance in fungal and bacterial infections.
- Elevated calprotectin correlates with protection against neonatal sepsis in humans.
Conclusions:
- Defensins and calprotectin act synergistically to enhance epithelial barrier function.
- These AMPs play a critical role in innate immunity, controlling microbial populations and stimulating immune responses.
- Calprotectin exhibits context-dependent functions, contributing to both direct microbial inhibition and immune activation.
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