LL37
Stocked in 10mg at MontanaPep in Great Falls, Montana. Sold for laboratory research use only.
| Size | Catalog no. | Price per vial |
|---|---|---|
| 10mg | 375 | $40 |
Classification
Endogenous human antimicrobial peptide with genuinely two-sided cancer biology
Structure and chemistry
LL-37 is a 37-amino-acid peptide released by enzymatic cleavage from the C-terminus of hCAP18, the human cathelicidin antimicrobial protein encoded by the CAMP gene. The full hCAP18 protein comprises a 30-residue signal peptide, a 103-residue cathelin prodomain, and the 37-residue active C-terminal domain that is LL-37. Its name comes from its two leading leucine residues and its length. It carries a net positive charge and is amphiphilic. It is the only cathelicidin found in humans.
What the published research shows
LL-37 has a substantial and high-quality research literature — and that literature does not point in one direction. Its cancer biology in particular is genuinely contradictory and tissue-specific, a point the published reviews make explicitly rather than as a caveat. Published work shows it promotes tumour development in some tissues and suppresses it in others, and which effect predominates depends on receptor expression patterns that vary by cell type.
Mechanism of action
Its antimicrobial action is physical: the cationic, amphiphilic peptide is electrostatically attracted to negatively charged bacterial membranes and disrupts them. Beyond that it is genuinely multifunctional, acting through the formyl peptide receptor FPR2 (also called FPRL1), the epidermal growth factor receptor, and ERBb2 — driving chemotaxis, angiogenesis, cytokine release, cell migration and wound closure. Those same growth-factor-receptor pathways are why its effects on tumour biology cut both ways.
Development history
LL-37 was not developed as a drug. It is an endogenous component of human innate immunity, stored primarily in the secondary granules of neutrophils and expressed widely in leukocytes and epithelial cells, where it forms part of the first line of defence at barrier surfaces.
Current regulatory status
LL-37 is not approved by the FDA or any regulator for any indication. Cathelicidin LL-37 was nominated to FDA’s bulk drug substances list for pharmacy compounding; the nomination was withdrawn.
Analytical testing
A 37-residue cationic peptide is a demanding synthesis, and truncated or deletion sequences are a realistic impurity class — published work notes that shortened LL-37 fragments retain activity, meaning related impurities may be biologically active rather than inert. Mass spectrometry against a certified reference standard is necessary, and because the peptide is highly cationic, counterion identity and content (typically trifluoroacetate or acetate) materially affect what a stated milligram figure means.
Ordering from Great Falls
MontanaPep, also known as Montana Peptides, is an independently owned supplier based at 715 13th Ave S, Great Falls, Montana. Local pickup is available by arrangement, and we ship to research addresses across Montana including Billings, Missoula, Bozeman, Helena, Butte, Kalispell and Havre. Call (406) 799-0812 or email customerservice@montanapep.com.