Buy LL-37 peptide

This antimicrobial peptide LL-37 is a research-grade reagent that represents one of the most important molecules in the human innate immune system. LL-37 is a 37-amino acid, cationic peptide derived from the C-terminus of the human cathelicidin antimicrobial protein (hCAP18). It is the only cathelicidin found in humans and acts as a crucial first line of defense against invading pathogens.

Beyond its direct killing ability, LL-37 is a pleiotropic molecule that actively orchestrates the body’s immune response. As of 2025, with the rising threat of antibiotic resistance, the study of host defense peptides like LL-37 has become a critical area of research. Our synthetic LL-37 provides a pure, stable, and highly active compound for investigating these multifaceted roles. This product is intended strictly for in-vitro and laboratory research applications.

The Dual Function of Our Antimicrobial Peptide LL-37

The scientific fascination with LL-37 stems from its dual role as both a direct weapon against microbes and a messenger that directs the immune system. Our commitment to high purity ensures researchers can accurately study both of these intricate functions.

Direct Antimicrobial Mechanism: Membrane Disruption

The primary function of our antimicrobial peptide LL-37 is its ability to kill a wide range of pathogens directly.

Broad-Spectrum Activity: It is effective against numerous gram-positive and gram-negative bacteria (including multi-drug resistant strains like MRSA), fungi, and enveloped viruses.

Mechanism of Action: As a cationic and amphipathic peptide, LL-37 is electrostatically attracted to the negatively charged outer membranes of microbes. It then inserts itself into the lipid bilayer, disrupting the membrane’s integrity, forming pores, and causing leakage of cellular contents, leading to rapid cell death. This physical mechanism makes it difficult for bacteria to develop resistance compared to traditional antibiotics.

Complex Immunomodulatory Roles

Perhaps the more profound research area for LL-37 is its function as a signaling molecule, or “alarmin,” that shapes the immune response.

Chemoattraction: It acts as a potent chemoattractant, recruiting key immune cells like neutrophils, monocytes, and T-cells to the site of an infection or injury.

Inflammation Modulation: LL-37 has a complex, context-dependent role in inflammation. It can promote inflammation to help clear an infection but can also bind and neutralize pro-inflammatory bacterial components like lipopolysaccharide (LPS), thereby preventing excessive inflammation and sepsis in research models.

Wound Healing and Angiogenesis: It has been shown to promote the proliferation and migration of epithelial cells and to stimulate angiogenesis (the formation of new blood vessels), both of which are critical processes for tissue repair.

Purity and Quality for Immunological Studies

High-Fidelity Synthesis: Precisely synthesized to match the 37-amino acid sequence of the natural human peptide.

HPLC Purification: Purified to >98% to remove impurities and ensure high bioactivity.

Endotoxin Tested: Critically, our LL-37 is tested for endotoxin levels to ensure that observed immune responses in cell cultures are due to the peptide itself and not bacterial contaminants.

Lyophilization: Provided as a stable, freeze-dried powder for consistent performance.

IMPORTANT LEGAL DISCLAIMER: This product is intended for laboratory research purposes ONLY. It is not for human or veterinary use. It is not an antibiotic, drug, dietary supplement, or cosmetic and is not intended to diagnose, treat, cure, or prevent any disease. It must be handled only by qualified professionals in a controlled research setting.

 

FAQs (Frequently Asked Questions)

What is LL-37?

It is the 37-amino acid, C-terminal fragment of the human cathelicidin protein (hCAP18). It is a natural host defense peptide and a critical component of the human innate immune system, possessing both direct antimicrobial and immune-modulating properties.

How does it work as an antimicrobial peptide?

LL-37 has a positive charge that attracts it to the negatively charged membranes of microbes. It physically disrupts these membranes, creating pores that cause the cell to leak and die. This direct physical action is a key area of study for combating antibiotic-resistant bacteria.

What are the “immunomodulatory” functions of it?

Beyond killing microbes, LL-37 acts as a signaling molecule. It can call other immune cells to an area of infection (chemoattraction), regulate the inflammatory response, and promote processes like wound healing and new blood vessel formation (angiogenesis).

What is the purity of your antimicrobial peptide LL-37?

Our antimicrobial peptide LL-37 is guaranteed to have a purity level exceeding 98%, as verified by High-Performance Liquid Chromatography (HPLC). It is also tested to ensure low endotoxin levels, which is critical for immunological research.

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