Disclaimer
CompoundIQ publishes research summaries for informational and educational purposes only. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. Always consult a licensed healthcare provider. Many compounds listed are research chemicals not approved for human use.
LL-37
Also known as: Cathelicidin, CAP-18, Human Cathelicidin Antimicrobial Peptide, hCAP-18
LL-37 is the only human cathelicidin antimicrobial peptide, a 37-amino-acid peptide cleaved from the precursor protein hCAP-18. It plays a critical role in innate immune defense against bacteria, viruses, and fungi, and also modulates inflammation, wound healing, and angiogenesis. Research interest has expanded beyond antimicrobial applications to include its immunomodulatory and tissue-repair properties.
Risk Level
Medium RiskDifficulty
Advanced| CAS Number | 154947-66-7 |
| Class | Peptide |
| Category | Well-Known Peptides |
Mechanism of Action
LL-37 disrupts microbial membranes through electrostatic interaction with negatively charged phospholipids, forming pores that cause cell lysis. Beyond direct antimicrobial activity, it modulates toll-like receptor signaling, recruits immune cells through chemotactic activity, and neutralizes bacterial endotoxins (LPS). It also promotes wound healing by stimulating keratinocyte and endothelial cell migration and proliferation through transactivation of the EGFR pathway.
Dosing Research
Research dosing varies widely by application and route, with no standardized human protocol established. Subcutaneous doses of 50-100 mcg have been explored in experimental settings. Topical and inhaled formulations are under investigation for wound and respiratory infections respectively.
Side Effects & Risks
Injection site pain and inflammatory reactions are the primary reported concerns. At high concentrations, LL-37 can exhibit cytotoxicity to host cells due to its membrane-disrupting mechanism. Overexpression has been linked to inflammatory conditions such as rosacea and psoriasis. Immune overstimulation is a theoretical risk, and standardized safety data from human trials is very limited.
Research Studies
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Disclaimer
CompoundIQ publishes research summaries for informational and educational purposes only. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. Always consult a licensed healthcare provider. Many compounds listed are research chemicals not approved for human use.