Peptide Handbook
Specialized Peptides

LL-37

Cathelicidin Antimicrobial Peptide

Updated April 14, 2026

What is LL-37?

The only human cathelicidin — a 37-amino-acid alpha-helical peptide cleaved from the hCAP18 precursor by proteinase 3 in neutrophils. LL-37 has direct bactericidal activity against Gram-positive and Gram-negative bacteria, biofilm disruption capability, and potent immunomodulatory effects including chemokine induction, angiogenesis promotion, and wound healing acceleration. Its amphipathic alpha-helix inserts into bacterial membranes, causing rapid lysis.

Research Profile

Structure 37 amino acids (~4,493 Da) — alpha-helical, amphipathic
Targets Bacterial membranes (direct lysis), FPR2, P2X7, biofilm matrix
Research Focus Antimicrobial defense, biofilm disruption, wound healing, innate immunity
Reconstitution Sterile water or PBS — 1 mg/mL
Stability 14 days at 2–8°C; avoid repeated freeze-thaw
Key distinction: The sole human cathelicidin — the only endogenous peptide with combined direct bactericidal activity, biofilm disruption, and immune cell chemotaxis in a single molecule.

Published Research

[1] Vandamme D et al. A comprehensive summary of LL-37, the factotum human cathelicidin peptide. Cell Immunol 2012;280:22-35 — PubMed 23246832
[2] Overhage J et al. Human host defense peptide LL-37 prevents bacterial biofilm formation. Infect Immun 2008;76:4176-4182 — PubMed 18591225
Research Use Only. All products sold by Lumen Peppers are intended solely for in vitro research and laboratory purposes. They are not drugs, supplements, or foods. Nothing on this page constitutes medical advice. Researchers are responsible for compliance with all applicable regulations. Last updated: April 14, 2026.

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