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Updated: Aug 17, 2026

An Intravital Microscopy-Based Approach to Assess Intestinal Permeability and Epithelial Cell Shedding Performance
Published on: December 3, 2020
Events at the host-microbial interface of the gastrointestinal tract. V. Paneth cell alpha-defensins in intestinal
1Dept. of Medical Microbiology and Immunology, University of California School of Medicine, One Shields Ave., Tupper Hall Rm. 3146, Davis, CA 95616, USA.
Abstract:
Host defense of the small intestine is mediated, in part, by antimicrobial peptides, including alpha-defensins. In the small intestine, Paneth cells, specialized secretory epithelial cells located at the base of the crypt invaginations lining the intestinal wall, produce alpha-defensins. The alpha-defensins are cysteine-rich cationic peptides with antibiotic activity against a wide range of bacteria and other microbes. Studies of transgenic and knockout mice have supported a pivotal role of Paneth cell alpha-defensins in protection from bacterial pathogens. New data suggest that deficient expression of Paneth cell alpha-defensins may contribute to the pathophysiology of Crohn's disease, a chronic inflammatory bowel disease.
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