Antimicrobial · Research Phase
Alpha-Defensin 5
No lawful US pathway
01 · Overview
Alpha-defensin 5, also called human defensin 5 or HD-5, is an alpha-defensin secreted by Paneth cells, the specialized epithelia of the small intestinal crypt (PMID 12660734). Its disulfide-stabilized structure supports antimicrobial activity demonstrated in vitro (PMID 12660734).
HD-5 is considered part of the innate defense that shapes the small intestinal microbial environment. Altered HD-5 expression has been linked to ileal Crohn disease.
02 · Research summary & key findings
Transgenic mice expressing human HD-5 in Paneth cells, with storage and processing matching that seen in humans, were markedly more resistant to oral challenge with Salmonella than control mice (PMID 12660734). In an independent cohort of newly diagnosed, untreated pediatric patients, small intestinal HD-5 and TCF-4 messenger RNA were significantly reduced in ileal Crohn disease compared with controls (PMID 19904243). Therapeutic strategies to augment HD-5 or deliver recombinant peptide remain at an early research stage, and no clinical trials were identified.
03 · Regulatory status
Alpha-Defensin 5 is in the research phase with limited clinical data in humans. Current evidence is primarily derived from preclinical (animal or in vitro) studies.
No lawful pathway today
Alpha-Defensin 5 is not FDA-approved and does not currently have a lawful prescription or compounding pathway in the United States, so we do not sell it and will not book a consultation for it. That can change: in 2026 FDA began reviewing several peptides for compounding.
See the 3 FDA-approved compounds in Antimicrobial
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04 · Administration routes
- Oral
- Topical
References
- [1]Protection against enteric salmonellosis in transgenic mice expressing a human intestinal defensin Nature, 2003. PMID 12660734
- [2]Defective paneth cell-mediated host defense in pediatric ileal Crohn's disease Am J Gastroenterol, 2010. PMID 19904243
Primary literature
- PubMed: "Alpha-Defensin 5"
Peer-reviewed literature indexed by the National Library of Medicine.
- ClinicalTrials.gov: "Alpha-Defensin 5"
Registered interventional and observational studies, including status and phase.
- PubChem: "Alpha-Defensin 5"
Chemical structure, molecular properties, and bioactivity data.
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