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Updated: Oct 15, 2025
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An Intravital Microscopy-Based Approach to Assess Intestinal Permeability and Epithelial Cell Shedding Performance
Published on: December 3, 2020
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Epithelial integrity, junctional complexes, and biomarkers associated with intestinal functions
Arash Alizadeh1, Peyman Akbari2, Johan Garssen2,3
1Division of Pharmacology and Toxicology, Department of Basic Science, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
Tissue Barriers
|November 1, 2021
Summary
A healthy intestinal barrier, maintained by tight junctions, is vital for immune balance. This review details tight junction proteins and biomarkers for gastrointestinal integrity.
Area of Science:
- Gastroenterology
- Cell Biology
- Immunology
Background:
- The intestinal barrier prevents immune overactivation and chronic inflammation.
- Epithelial cells form this barrier via interconnected tight junctions.
- Tight junctions comprise transmembrane and scaffolding proteins.
Purpose of the Study:
- To review the molecular structure of intestinal epithelial tight junction proteins.
- To characterize their organization and interactions.
- To discuss biomarkers of impaired gastrointestinal integrity.
Main Methods:
- Literature review of tight junction protein structure and function.
- Analysis of protein interactions within the tight junction network.
- Identification and discussion of clinical biomarkers.
Main Results:
- Detailed description of transmembrane proteins (occludin, claudins, JAMs, tricellulin).
- Explanation of scaffolding proteins (ZOs, cingulin, afadin) linking to the cytoskeleton.
- Highlighting the cooperative function of these proteins in barrier integrity.
Conclusions:
- Intact tight junctions are essential for maintaining intestinal immune homeostasis.
- Understanding these protein interactions is key to addressing gastrointestinal integrity issues.
- Biomarkers for impaired gut integrity are clinically relevant.
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