Cathelicidin · LL37 · hCAP-18
LL-37 is the only human cathelicidin antimicrobial peptide, a 37-amino acid peptide cleaved from the precursor protein hCAP18 by proteinase 3. It is a key component of the innate immune system, produced by neutrophils, macrophages, epithelial cells, and mast cells in response to infection. LL-37 directly kills bacteria, fungi, and enveloped viruses through membrane disruption, while also modulating immune cell recruitment, wound healing, and inflammatory signaling. It represents a naturally occurring antibiotic peptide that pathogens have difficulty developing resistance to due to its membrane-targeting mechanism.
Can be taken any time. Short courses (2-4 weeks) for infections. Pin alone or with limited safe compounds only.
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
LL-37 adopts an amphipathic alpha-helical structure that inserts into microbial membranes, creating pores that disrupt membrane integrity and kill pathogens. This mechanism is effective against gram-positive and gram-negative bacteria, fungi, and enveloped viruses. Beyond direct killing, LL-37 recruits immune cells to infection sites (chemotaxis), modulates inflammatory cytokine production, neutralizes bacterial endotoxin (LPS), promotes angiogenesis and wound healing, and disrupts bacterial biofilms that protect chronic infections.
Days 1-7: Immune augmentation begins. Most relevant during active infection.
Weeks 2-4: Chronic infection support. Biofilm disruption effects accumulate.
Short courses typical. Extended use not standard.
Each reference below was re-fetched from its PubMed record, and the quoted sentence was confirmed to appear in that abstract and to support the claim it sits under. Follow any of them to read the source.
Evidence boundary from the checked abstract: LL-37 also stimulates the migration and differentiation of mesenchymal stem cells (MSCs).
LL-37 also stimulates the migration and differentiation of mesenchymal stem cells (MSCs).
Regulation of LL-37 in Bone and Periodontium Regeneration.
Evidence scope. This entry supports only the exact statement quoted from the live abstract; it does not independently verify OnePin's displayed dose, route, frequency, formulation, population, or broader mechanism.
Claims we could not support
No abstract we checked supports these for this molecule at this route. That is not the same as saying they are false — it marks where the evidence is missing.
Dose/route: 25 mcg; SubQ injection; Daily or as needed. No checked live PubMed abstract verified this exact displayed dose, route, and frequency for the same molecule/formulation and relevant population.
Primary safety claim: No primary safety text present in source JSON. No checked live PubMed abstract directly verified this source-JSON safety claim at the displayed formulation, route, and regimen.
Natural antibiotic
Confirmed. LL-37 directly kills pathogens through membrane disruption. Resistance development is difficult because mechanism targets fundamental membrane structure.
Confirmed in vitro and animal models. Relevant for chronic infections with biofilm component.
Two different questions: what is documented about running these together, and what is documented about drawing them into the same syringe. A good pharmacological partner can still have to be pinned separately.
Check any specific pair in the Stack & Interaction Checker, which answers both questions separately. Absence of a documented conflict is not evidence of safety.
SubQ
Antimicrobial and immune signaling effects
Enzymatic degradation (proteases at site of action)
Storage. Standard BAC water 2-8C. Stable for 28 days. Protect from light.
Not FDA-approved as injectable. Available as research peptide. WADA status not specifically listed.
Put it to work
Open LL-37 straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
Open LL-37 in the app →Go deeper
The complete LL-37 walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
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