Research Only Healing & Recovery

LL-37

also known as: Cathelicidin LL-37, human cationic antimicrobial protein 18 (hCAP18), CAMP

The only human cathelicidin — an antimicrobial peptide with direct activity against bacteria, fungi, viruses, and biofilms, with additional roles in wound healing and immune signaling.

The 37-residue active peptide released from the human cathelicidin precursor hCAP-18 (encoded by the CAMP gene), with direct microbicidal activity and pleiotropic effects on wound healing, angiogenesis, and innate immune signaling.

Mechanism of action

Direct antimicrobial activity via membrane disruption of gram-positive and gram-negative bacteria, fungi, and enveloped viruses. Modulates macrophage polarization, neutralizes LPS, promotes keratinocyte migration, and stimulates angiogenesis via FPRL1 receptor activation. Abnormally elevated in rosacea and some psoriasis phenotypes (pathogenic at high local concentrations).

Primary uses

Chronic wound research
Antimicrobial / biofilm research
Community use for chronic infection in functional-medicine settings

Typical dosing

100–500 mcg daily or every other day (subcutaneous (community); topical (research))

Community dosing only; no clinical standard. High doses have been associated with flushing and pro-inflammatory effects.

Regulatory status

Not approved. Preclinical and early clinical research in wound healing, rosacea, and chronic infection. Discussed extensively in functional-medicine settings for chronic biofilm-associated infection.

References

[review] Vandamme D, et al. "A comprehensive summary of LL-37, the factotum human cathelicidin peptide." Cell Immunol, 2012;280:22-35.
[pubmed] Yamasaki K, et al. "Increased serine protease activity and cathelicidin promotes skin inflammation in rosacea." Nat Med, 2007;13:975-980.

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Disclaimer

This entry is for educational purposes only and does not constitute medical advice. Dosing information reflects published regulatory or research data and is not a recommendation. Many compounds described here are not approved for human use in the United States. Consult a licensed medical professional before considering any peptide therapy.