LL-37 — Antimicrobial Peptide Research Reference (Ireland 2026)

By the Peptides Lab Ireland research team · Updated July 2026 · Research use only

LL-37 is the only human cathelicidin , with the C-terminal 37 amino acid fragment of the precursor protein hCAP-18. It is one of the central research references in antimicrobial peptide biology and innate immunity, with a very large published research literature. This reference is for Irish research groups working with LL-37 in preclinical protocols.

What is LL-37?

LL-37 is a 37 amino acid amphipathic α-helical cationic peptide (starts with the letters Leu-Leu, hence the “LL”). It is the biologically active fragment cleaved from the precursor hCAP-18 (encoded by the CAMP gene) at sites of infection or inflammation.

• Sequence: LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES
• Amino acids: 37
• Class: Cathelicidin family, cationic amphipathic α-helical AMP
• Molecular weight: ≈ 4493 Da

Research applications

LL-37 research literature covers:

• Antimicrobial peptide biology , the central research reference in AMP research literature
• Innate immunity research , with LL-37 acts at the interface of pathogen defence and immune activation
• Membrane biology research , cationic amphipathic peptide membrane disruption mechanisms
• Wound healing research . LL-37 has documented roles in re-epithelialisation and angiogenesis
• Inflammation and autoimmunity research : LL-37 is a research reference in psoriasis and lupus biology models
• Anti-biofilm research . Cationic peptide activity against microbial biofilms
• Cancer research models . Reported effects on tumour cell membrane biology

LL-37 in the immune peptide research space

LL-37 sits alongside other immune-modulation research references at Peptides Lab Ireland:

• KPV and α-MSH C-terminal anti-inflammatory tripeptide
• Thymosin Alpha-1 , 28 amino acid thymic immunomodulator
• Thymalin , with thymic extract research reference
• VIP , vasoactive intestinal peptide (gastrointestinal-immune interface)

Reconstitution

LL-37 reconstitutes with bacteriostatic water using the standard technique and see our reconstitution guide. As a cationic amphipathic peptide, some batches have compound-specific reconstitution notes — check the batch COA.

Regulatory context

LL-37 isn’t approved as a medicinal product in Ireland. Supplied strictly for in-vitro laboratory research and educational use. See our HPRA regulations guide.

Sourcing LL-37 in Ireland

Peptides Lab Ireland stocks HPLC-verified LL-37 with per-batch Certificate of Analysis. See the product page.

See also

• Immune Modulation peptides category
• Reconstitution guide
• How to Read a Peptide COA

For laboratory research use only. Not intended for human or veterinary use.