What Is LL-37?
LL-37 is a 37-amino-acid cationic peptide released from the human cathelicidin precursor hCAP18. It is studied as both a membrane-active host-defense peptide and a signaling molecule in innate-immune and barrier-cell models.
Overview
Laboratories use LL-37 to compare direct interactions with microbial-style membranes against receptor-mediated effects in immune, epithelial, fibroblast, and endothelial systems. Its behavior changes with salt, serum, concentration, membrane composition, peptide aggregation, and cell type.
In plain language, LL-37 helps researchers separate two questions: whether a peptide acts directly on a membrane and whether it changes the messages sent by immune or barrier cells.
History
LL-37 was characterized in the 1990s as the active C-terminal peptide generated from human cathelicidin. Research then expanded from direct antimicrobial assays into membrane biophysics, inflammatory signaling, cell migration, and other context-dependent host-response models.
Research Findings
- LL-37 can bind and destabilize selected lipid membranes, with activity influenced by membrane composition and the surrounding medium.
- Primary human monocyte and epithelial models have shown ERK, p38, and other context-dependent signaling responses.
- The peptide can interact with microbial products such as lipopolysaccharide and alter innate-immune readouts.
- Opposing responses have been reported across different cell types, making concentration and model controls essential.
Documentation
Available analytical reports apply only to the exact product, strength, and lot identified on each report. A report for one strength or lot must not be assumed to cover another. Contact Fit Club Elite before ordering when a project requires lot-specific documentation.
Use Restrictions
For Research Use Only. Not for human or veterinary use. Not a food, drug, cosmetic, dietary supplement, or household product. Fit Club Elite does not provide medical, dosing, mixing, reconstitution, administration, or end-use guidance. Purchasers are responsible for lawful handling, storage, and use in an appropriate research setting.