Alpha-Defensin 5
Overview
Alpha-defensin 5 (HD5) is a 32-amino acid cationic peptide predominantly expressed by Paneth cells in the small intestinal crypts. It contains three disulfide bonds that stabilize its beta-sheet structure and enable membrane disruption of bacteria, fungi, and some viruses. HD5 plays a critical role in maintaining intestinal homeostasis by regulating gut microbiota composition and protecting the epithelial barrier. Altered HD5 expression has been implicated in inflammatory bowel disease, necrotizing enterocolitis, and susceptibility to enteric infections.
Key Research Findings
Preclinical studies have demonstrated that HD5 deficiency in mouse models increases susceptibility to intestinal pathogens and dysbiosis. Observational human studies have correlated reduced HD5 expression with Crohn disease severity and neonatal gut inflammation. Therapeutic strategies to augment HD5 expression or deliver recombinant peptide remain in early research stages with no clinical trials reported.
Oral, Topical
Research Phase
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