LL-37
Mechanism of action
What LL-37 does in the body — step by step.
LL-37 is the only human cathelicidin — a 37-amino-acid peptide produced by proteolytic cleavage from the precursor protein hCAP-18.
It acts directly antimicrobially by destabilising bacterial cell membranes (cationic charge + amphipathic helical structure).
In addition, LL-37 has immunomodulatory functions: it activates Toll-like receptors (TLR), promotes the chemotaxis of immune cells, stimulates angiogenesis via VEGFR-2 and accelerates wound healing.
Research status
How far along is the evidence?
Known risks
Without human data, safety statements are limited. What is known:
Cited studies
Chronological — links lead to the source.
Frequently asked questions
What is LL-37?+
LL-37 is the only human cathelicidin — a 37-amino-acid peptide produced by proteolytic cleavage from the precursor protein hCAP-18.
What type of peptide is LL-37?+
LL-37 belongs to the Antimicrobial peptide class.
What is LL-37 used for?+
In research, LL-37 has primarily been investigated in the context of: Immunomodulation, Recovery, Skin & hair. These are research findings (evidence: early clinical studies), not proven benefits in humans and not a usage recommendation.
Is LL-37 legal in Germany?+
LL-37 is not approved as a medicine in Germany. Obtaining it outside clinical studies is legally problematic.
Is LL-37 FDA-approved / legal in the US?+
No. LL-37 is not FDA-approved as a drug in the US; it is mostly sold as a research chemical and not for human consumption.
Is LL-37 legal in Canada?+
No. LL-37 is not authorized by Health Canada and not intended for human consumption.
Where can I buy LL-37?+
Peptica sells nothing and names no sources. LL-37 is "not approved" in Germany; obtaining unapproved substances outside clinical studies is illegal and carries quality and safety risks.
What is the dosage of LL-37?+
Peptica publishes no dosing. There are no approved dosing guidelines for LL-37; figures circulating online stem from animal studies or anecdote, not from validated human protocols. This is not medical advice.
Is LL-37 banned in sport (WADA)?+
LL-37 is currently not on the WADA Prohibited List.
What are the known risks of LL-37?+
Documented risks include: Potentially pro-inflammatory effects at high systemic concentration; Ambivalent evidence on its role in carcinogenesis: both tumour-suppressing and tumour-promoting effects described. This is not a complete safety assessment and not medical advice — see the risks section for the full list.
How well researched is LL-37?+
The evidence is classified as “early clinical studies”. 3 studies are cited on this page.
What is the molecular weight of LL-37?+
LL-37 has a molar mass of about 4493 Da.
Which peptides are related to LL-37?+
Closely related entries: BPC-157, TB-500. A direct side-by-side comparison is available via the compare function.
Dossier
Legal · Structure · Sources.
LL-37 is not an approved medicine in the EU. Clinical studies are ongoing within regulated trial programmes. Use outside controlled studies is not covered by any approval. Not on the WADA list. Importing it as a research chemical may, depending on the context, fall under the German Medicines Act (AMG).
Legal status varies by country and can change. This is not legal advice.
Methodology: Peptica compiles publicly available studies and regulatory information and assigns each statement an evidence level. Not medical advice. No warranty.