LL37 (5mg)

LL-37 is the only human cathelicidin antimicrobial peptide, derived from the C-terminal cleavage of the 18-kDa precursor protein hCAP18 by proteinase 3. It is a 37-amino-acid amphipathic alpha-helical peptide produced by neutrophils, macrophages, epithelial cells, and other cell types as part of the innate immune defense. LL-37's antimicrobial mechanism involves direct membrane disruption of microbial cells. Its amphipathic structure — with a hydrophobic face and a cationic (positively charged) face — enables it to insert into negatively charged microbial membranes, causing pore formation and cell lysis. It is active against a broad spectrum of Gram-positive and Gram-negative bacteria, fungi, and enveloped viruses. Crucially, LL-37 also disrupts bacterial biofilms at sub-bactericidal concentrations, a property that distinguishes it from many conventional antibiotics. Beyond direct antimicrobial activity, LL-37 serves as a potent immunomodulator. It recruits immune cells to infection sites by acting as a chemoattractant for neutrophils, monocytes, and T-cells via the formyl peptide receptor-like 1 (FPRL1). It promotes wound healing by stimulating angiogenesis and re-epithelialization. LL-37 also modulates Toll-like receptor signaling, enhancing the immune response to bacterial products while dampening potentially harmful excessive inflammatory responses.

LL-37 is the only human cathelicidin antimicrobial peptide, derived from the C-terminal cleavage of the 18-kDa precursor protein hCAP18 by proteinase 3. It is a 37-amino-acid amphipathic alpha-helical peptide produced by neutrophils, macrophages, epithelial cells, and other cell types as part of the innate immune defense. LL-37's antimicrobial mechanism involves direct membrane disruption of microbial cells. Its amphipathic structure — with a hydrophobic face and a cationic (positively charged) face — enables it to insert into negatively charged microbial membranes, causing pore formation and cell lysis. It is active against a broad spectrum of Gram-positive and Gram-negative bacteria, fungi, and enveloped viruses. Crucially, LL-37 also disrupts bacterial biofilms at sub-bactericidal concentrations, a property that distinguishes it from many conventional antibiotics. Beyond direct antimicrobial activity, LL-37 serves as a potent immunomodulator. It recruits immune cells to infection sites by acting as a chemoattractant for neutrophils, monocytes, and T-cells via the formyl peptide receptor-like 1 (FPRL1). It promotes wound healing by stimulating angiogenesis and re-epithelialization. LL-37 also modulates Toll-like receptor signaling, enhancing the immune response to bacterial products while dampening potentially harmful excessive inflammatory responses.

In vitro antimicrobial studies use 1-32 mcg/mL. Anti-biofilm activity observed at 0.5-4 mcg/mL. Wound healing studies in animals use topical application of 10-100 mcg/wound.

Store lyophilized (freeze-dried) powder at -20°C to 4°C in a dry environment protected from light. Unreconstituted peptide is stable for extended periods when stored properly.

Once reconstituted with bacteriostatic water or an appropriate solvent, store at 2-8°C and use within the timeframe specified on the Certificate of Analysis. Avoid repeated freeze-thaw cycles.

A Certificate of Analysis documenting purity, identity, and recommended storage conditions is included with every order.