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LL-37
Overview
The only human cathelicidin antimicrobial peptide, a 37-amino acid cationic peptide cleaved from the precursor protein hCAP18. LL-37 disrupts microbial membranes through electrostatic interactions and exerts broad-spectrum activity against bacteria, fungi, and enveloped viruses.
Mechanism of Action
Beyond direct antimicrobial effects, it modulates innate immunity by recruiting immune cells, promoting angiogenesis, and regulating inflammatory cytokine release.
Research Summary & Key Findings
Demonstrated broad-spectrum antimicrobial activity against antibiotic-resistant organisms including MRSA. Plays a role in wound healing and immune defense at epithelial surfaces. Dysregulation implicated in rosacea (overexpression) and chronic wounds (deficiency). Research suggests therapeutic potential in chronic infections and wound healing.
Clinical Status
LL-37 is in the research phase with limited clinical data in humans. Current evidence is primarily derived from preclinical (animal or in vitro) studies.
Administration Routes
References
Primary literature
- PubMed: "LL-37"
Peer-reviewed literature indexed by the National Library of Medicine.
- ClinicalTrials.gov: "LL-37"
Registered interventional and observational studies, including status and phase.
- PubChem: "LL-37"
Chemical structure, molecular properties, and bioactivity data.
Study-level citations for this compound are being verified against the primary sources before publication. The database queries above return the current indexed literature in the meantime.
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View detailsNo lawful pathway today
LL-37 is not FDA-approved and does not currently have a lawful prescription or compounding pathway in the United States, so there is nothing for us to sell you here and no consultation to book. That can change: eight peptides moved back to a lawful pathway in February 2026.
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