LL-37 (Cathelicidin, CAMP)
LL-37 is the body's own protective peptide, produced in the skin and mucous membranes, that destroys bacteria, viruses, and fungi. It is studied for healing chronic wounds, for acne and rosacea, and for fighting resistant bacteria.
37 amino acids: LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES. α-helical structure upon interaction with membranes. ~4493 Da. C-terminal fragment of hCAP18. The only known human cathelicidin.
A key antimicrobial peptide of innate immunity in the skin and mucous membranes. Neutralizes gram(+) and gram(-) bacteria, viruses, and fungi. ↓MRSA and MSSA biofilms from chronic wounds. ↑wound healing, ↑angiogenesis. Active in acne, rosacea, and chronic wounds. Modulates inflammation (↓IL-6, TNF-α).
Amphipathic α-helix → electrostatic interaction with the anionic bacterial membrane → insertion → pore formation. Immunomodulation: ↑chemotaxis of neutrophils and monocytes → ↑pathogen capture. ↓NLRP3/caspase-1/GSDMD (pyroptosis). ↑migration and division of skin cells → ↑epithelialization.
Studies used: topically — 5–10 mg in a cream/gel once daily; by injection (Research) — 0.5–1 mg SC into the affected area 2–3 times/week. It was not mixed with other peptides in the same syringe.
Level C Animal studies. Effects have been shown in animals. Whether they carry over to humans has not been proven. Mostly animal and in vitro data. High clinical potential.
⚠️ Broken down by skin proteases (degradation in vivo). Topical use is limited by penetration. No completed RCTs. Research only.
Research peptides are laboratory reagents (Research Use Only). They are not medicines and are not intended for use in humans or animals.