LL-37

LL-37 is a 37-amino acid human cathelicidin antimicrobial peptide (AMP). Its amphipathic helical structure enables insertion into microbial membranes, disrupting their integrity. Beyond antimicrobial activity, LL-37 modulates host immune responses through Toll-like receptor (TLR) interaction.

LL-37 acts as a direct antimicrobial agent, an immune modulator, and an angiogenesis promoter simultaneously. It activates FPR2 on immune cells, promotes VEGF and FGF-2 expression for wound-associated angiogenesis, stimulates keratinocyte migration, and modulates TLR-mediated innate immune activation.

Research areas include wound healing (accelerated closure and neovascularization), infection resistance (broad-spectrum activity against bacteria, fungi, and some viruses), anti-biofilm activity against resistant pathogens, and cancer research (pro-apoptotic effects in some cancer cell lines).

Store lyophilized at -20°C. Reconstituted solution stable 14 days at 2–8°C. LL-37's amphipathic properties can cause aggregation — use non-stick tubes and minimize adsorption to container surfaces.