LL-37
LL-37 (Cathelicidin Antimicrobial Peptide)
The only human cathelicidin — a natural antimicrobial peptide that is part of the innate immune system, with research spanning infection defense, wound healing, and inflammation.
LL-37 is not approved by the FDA for human use. It is sold strictly for research purposes only and is not intended for human consumption, diagnosis, treatment, or prevention of any disease or condition. Purchase and use is entirely at your own risk.
Sourcing for research purposes?
View at Ascension Peptides →What it is
LL-37 is a 37-amino acid peptide derived from the C-terminus of the human protein hCAP18 (human cathelicidin antimicrobial protein). It is the only cathelicidin in humans and is produced by neutrophils, NK cells, and epithelial cells as a first-line defense against pathogens.
Its biology is unusually complex — LL-37 can be anti-inflammatory or pro-inflammatory depending on the context, which has made research difficult to translate into simple therapeutic applications. It plays a role in wound healing, immune signaling, and potentially cancer biology.
What research shows
- Broad-spectrum antimicrobial activity against bacteria, fungi, and some viruses
- Anti-biofilm properties — disrupts established microbial communities
- Promotes wound healing and re-epithelialization
- Immune modulation — activates dendritic cells and promotes adaptive immune response
- Complex dual role in cancer — may be pro-tumor or anti-tumor depending on cancer type
What remains unknown
- Context-dependent inflammatory effects are not fully characterized
- Optimal dosing, route, and duration in humans for any indication
- Long-term safety profile with systemic administration
- Net effect in cancer biology — use with caution in any oncology context
Administration basics
Common use cases
Infection defense support, wound healing, immune modulation. Used cautiously given its complex biology.
Half-life
Short in plasma — rapidly degraded by proteases.
Administration
Subcutaneous injection. Topical use for wound applications.
Source this compound
Looking for LL-37?
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View at Ascension PeptidesResearch Protocols & Common Usage
Doses used in research
- Research studies have used 1–2mg per injection in experimental settings
- Community protocols commonly report 1–2mg subcutaneous injection 2–3x per week
Administration routes studied
Typical protocol duration
Community protocols typically report 4–8 week cycles. Most research has used short-term administration.
Common stacking protocols
- LL-37 + BPC-157 — combined in wound healing and gut repair protocols
- LL-37 + Thymosin Alpha-1 — combined for broad immune system support targeting both innate and adaptive immunity
Contraindications & combinations to avoid
- Autoimmune conditions — LL-37's immune-activating properties could exacerbate inflammatory autoimmune diseases
- Active inflammatory skin conditions such as psoriasis — LL-37 plays a documented pathogenic role in psoriasis; systemic administration may worsen this condition
- Sepsis or systemic inflammation — use with extreme caution; LL-37 can be pro-inflammatory in certain contexts
Dosing information reflects doses used in published research and commonly reported community protocols only. This is not a personal recommendation. These compounds are not FDA-approved for human use in the contexts described. Consult a qualified healthcare provider before starting any protocol.
Considering stacking?
See the stacking guide for common combinations with LL-37 and what to avoid.
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Community Reviews
Reviews reflect individual user experiences with research compounds and are not medical advice. Results vary. These compounds are not FDA approved for human use. Peptelligent does not verify reported experiences.
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