Overview
What it is.
LL-37 is a peptide the human body produces naturally as part of its first-line, innate immune response, studied for antimicrobial and immune-signaling properties. Research is largely preclinical.
Research Areas
- Studied for its potential role in antimicrobial-defense research
- Studied for its potential role in innate-immune-signaling research
- Studied for its potential role in wound-site immune-activity research
Batch & Testing
Proof, not promises.
COA ships with every order
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Research Deep-Dive
How it works.
Research Deep-Dive
How it works.
LL-37 is a peptide the human body produces naturally as part of its first-line, innate immune response — the only cathelicidin-family antimicrobial peptide encoded by the human genome. It's studied for both direct antimicrobial activity and broader immune-signaling roles, but remains without an FDA-approved product.
LL-37 disrupts microbial cell membranes directly and also acts as a signaling molecule that recruits and activates immune cells at sites of infection or injury — a dual mechanism that makes it of interest for both infection control and wound healing, though the same membrane-disrupting activity limits the concentrations that can be used safely.
Use Cases Explored
- Studied for a potential role in antimicrobial defense against resistant pathogens
- Studied for a potential role in innate immune signaling
- Studied for a potential role in wound-site immune activity and healing
The Evidence
Phase IIb wound trial
A randomized controlled trial in 148 patients with venous leg ulcers found complete wound closure in about 28% of the LL-37 group versus 8% on placebo in the larger-wound subgroup — one of the few controlled human trials of LL-37 to show a clear treatment effect.
Diabetic foot ulcer trial
A separate randomized controlled trial (n=48) found topical LL-37 cream significantly increased granulation tissue formation compared with placebo in diabetic foot ulcers, though this remains the only completed human interventional study of its kind.
Early-phase oncology trials
Small Phase I trials have tested intratumoral LL-37 injection in cutaneous melanoma metastases, finding acceptable tolerability but variable biological response — early and exploratory, not indicative of efficacy.
Translational barriers
LL-37 has a serum half-life measured in minutes due to rapid enzymatic degradation, and at the concentrations needed for reliable antimicrobial effect it can begin to damage human cells through the same membrane-disrupting mechanism it uses against bacteria — a narrow therapeutic window that has slowed clinical development despite encouraging preclinical data.
Specifications
The essentials.
Specifications
The essentials.
- Form
- Lyophilized powder
- Storage
- Store in a cool, dry place. Refrigerate at 2–8°C after reconstitution
- Shelf life
- 24 months lyophilized; 4–6 weeks refrigerated after reconstitution
- Solubility
- Reconstitute with bacteriostatic water
- Vial capacity
- 3 ml glass vial
Questions
LL-37 FAQ
Questions
LL-37 FAQ
What is LL-37 studied for?+
LL-37 is studied for its potential role in antimicrobial-defense research, innate-immune-signaling research, and wound-site immune-activity research.
What role does LL-37 play in the body's own defenses?+
It's a peptide the human body produces naturally as part of its first-line, innate immune response — that native role is what makes it a frequently studied antimicrobial and immune-signaling compound, though most supporting research remains preclinical.
How should LL-37 be handled and stored?+
It ships as a lyophilized powder in a single 5 mg size. Reconstitute with bacteriostatic water and refrigerate at 2–8°C after mixing — good for roughly 4–6 weeks refrigerated, or up to 24 months unreconstituted in a cool, dry place.
What testing does this batch undergo?+
Every batch is HPLC tested for purity and identity, plus sterility and endotoxin screening, before release. The Certificate of Analysis for that lot ships with your order.
Neuro
LL-37
Cathelicidin
A naturally occurring antimicrobial peptide studied for innate-immune-defense research.
Size
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All products sold by One Tap Peptides are intended for laboratory research use only. Not for human consumption. Not intended for animal use. Not intended for diagnostic or therapeutic purposes.
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