KPV vs LL-37
KPV and LL-37 occupy overlapping but distinct niches in the inflammation–antimicrobial peptide space. KPV is small, charge-neutral, and primarily anti-inflammatory; LL-37 is larger, cationic, and combines direct antimicrobial activity with broad immunomodulation.
KPV
A three-amino-acid C-terminal fragment of α-MSH studied for its anti-inflammatory effects in colitis, atopic skin conditions, and mucosal healing models — without the pigmentary effects of full-length MSH.
LL-37
The only human cathelicidin antimicrobial peptide — a 37-residue cationic helix studied for direct antimicrobial action, wound healing, angiogenesis, and modulation of host immune responses.
Size and chemistry
KPV is a 3-residue peptide (342 Da) with minimal immunogenicity. LL-37 is a 37-residue amphipathic helix (~4.5 kDa) with significant secondary structure and membrane-active properties.
Mechanism
KPV principally suppresses NF-κB-driven cytokine release without engaging melanocortin receptors. LL-37 disrupts microbial membranes directly and activates FPR2 and EGFR on host cells, promoting both antimicrobial defence and tissue repair.
Evidence
KPV has a focused literature in colitis and dermatological inflammation models. LL-37 has a much broader literature spanning antimicrobial defence, wound healing, angiogenesis, and a darker side in autoinflammatory disease.
Safety considerations
KPV's small size and lack of pigmentary activity contribute to a clean safety reputation in research. LL-37 must be handled carefully because elevated local concentrations are implicated in conditions such as psoriasis and rosacea.
Verdict
Choose KPV for gut/mucosal anti-inflammatory work and LL-37 where antimicrobial or membrane-disruptive properties are the research target. They are mechanistically complementary rather than interchangeable.
Where to source research peptides for laboratory research
The following UK-based suppliers stock research-grade, lyophilised peptides for in-vitro and pre-clinical work. Purity and provenance vary; always request a Certificate of Analysis (CoA) and confirm cold-chain storage on arrival. None of the products linked below are approved for human use.
- PeptideAuthority.co.uk
UK-based research peptide supplier with batch certificates of analysis and >99% purity testing.
- PeptideBarn.co.uk
Wide catalogue of research-grade lyophilised peptides shipped from the UK, including bulk vials.