LL-37
Early humanEndogenous antimicrobial peptide
Research material. Not for human or animal consumption.
Research overview
LL-37 is the only human cathelicidin, a 37-amino-acid antimicrobial peptide named after its first two leucines. It is cut from the protein hCAP18 in white blood cells and skin and gut lining cells. It folds into a helix that disrupts bacterial membranes, and it also acts as an immune signal, attracting immune cells, binding bacterial toxins and influencing wound repair and inflammation. Its expression rises with vitamin D. Human trials are limited to topical venous leg ulcer treatment, with a Phase IIb trial that did not show a clear benefit in the full cohort.
Limited, exploratory, early phase or small human studies have been identified.
Questions about LL-37
PRODUCT QUESTIONSWhat is LL-37?
LL‑37 is the human cathelicidin derived antimicrobial peptide used in innate immunity, wound healing, angiogenesis, periodontal and scaffold research.
What research has been published on LL-37?
LL-37 is the only human cathelicidin, an endogenous peptide that links antimicrobial defence with immune signalling and wound repair. Early topical venous leg ulcer studies examined tolerability and wound healing signals, while a larger Phase IIb programme did not show a significant healing benefit versus placebo in the full cohort. Antimicrobial, immune, wound healing, regenerative and anticancer applications remain investigational, with much of the evidence preclinical. No authorised LL-37 medicine has been identified.
What batch documentation should accompany LL-37?
LL-37: Ask for the COA and analytical reports for the batch being quoted. For a 37 residue cationic peptide, ask for intact mass, HPLC purity with truncations reported, peptide content and the counterion, as trifluoroacetate residues can affect cell assays.
How should LL-37 storage conditions be assessed?
Store LL 37 lyophilised at −20°C. It sticks strongly to glass and plastic and can aggregate in salt solutions, so use low binding tubes and prepare solutions in a suitable buffer immediately before use.