# LL-37 Research — Full Context > LL-37 cathelicidin research — human antimicrobial peptide mechanisms, immunomodulation, wound healing, anti-biofilm activity, innate immunity, and infection defense studies with PubMed citations. ## About This Site LL-37 Research is part of the System Peptides Research Network — a collection of 21 specialized peptide research resources. Each site focuses on a specific compound or research area, providing peer-reviewed content sourced exclusively from PubMed-indexed publications. This site is an educational resource and does not sell products directly. Research-grade peptides are available at researchvials.com. ## Site Identity - Domain: https://ll37research.com - Network: System Peptides Research Network - Parent Store: https://researchvials.com - Wikidata: https://www.wikidata.org/wiki/Q139376131 - ORCID: https://orcid.org/0009-0004-9811-6147 ## Research Focus Peptides ### LL-37 (Cathelicidin) (LL-37, Cathelicidin, CAP18, hCAP18) - CAS: 154947-66-7 - Molecular Weight: 4493.33 g/mol - Sequence: Leu-Leu-Gly-Asp-Phe-Phe-Arg-Lys-Ser-Lys-Glu-Lys-Ile-Gly-Lys-Glu-Phe-Lys-Arg-Ile-Val-Gln-Arg-Ile-Lys-Asp-Phe-Leu-Arg-Asn-Leu-Val-Pro-Arg-Thr-Glu-Ser - Mechanism: LL-37 is the only human cathelicidin antimicrobial peptide, derived from the C-terminal cleavage of the 18-kDa precursor protein hCAP18 by proteinase 3. It is a 37-amino-acid amphipathic alpha-helical peptide produced by neutrophils, macrophages, epithelial cells, and other cell types as part of the... - Research Areas: Antimicrobial Peptides, Innate Immunity, Wound Healing, Anti-Biofilm, Immunomodulation Key Findings: - - - - ## Site Pages - Home: https://ll37research.com/ - Research Profiles: https://ll37research.com/research/ - Articles: https://ll37research.com/articles/ - FAQ: https://ll37research.com/faq/ - COA Guide: https://ll37research.com/coa-guide/ - About: https://ll37research.com/about/ - Research Calculator (88+ protocols, dosing phases, mechanisms of action, syringe visualization, FAQs): https://ll37research.com/tools/dosing-calculator/ - Privacy Policy: https://ll37research.com/privacy/ - Accessibility Statement: https://ll37research.com/accessibility/ - Cookie Policy: https://ll37research.com/cookies/ - Disclaimer: https://ll37research.com/disclaimer/ ## Articles ### Essential Peptides for Anti-Aging and Longevity Research URL: https://ll37research.com/articles/essential-peptides-anti-aging-longevity-research/ ### Peptide Research Trends to Watch in 2026 URL: https://ll37research.com/articles/peptide-research-trends-2026/ ### Reading PubMed: A Researcher's Guide to Peptide Literature URL: https://ll37research.com/articles/reading-pubmed-researchers-guide-peptide-literature/ ## Research Applications - Immune Support: Acts as a crucial part of the innate immune system, functioning as a natural antibiotic to directly neutralize microbes and activate dendritic cells to detect threats. - Recovery & Healing: Beyond antimicrobial activity, LL-37 promotes wound closure through angiogenesis and re-epithelialization, and inhibits biofilm formation at wound sites. - Anti-Biofilm Research: LL-37 disrupts established bacterial biofilms — a major challenge in chronic wound and medical device infection research. ## Frequently Asked Questions Q: What is LL-37? A: LL-37 is the only cathelicidin-derived antimicrobial peptide in humans. It is a 37-amino acid peptide cleaved from the precursor protein hCAP18 and plays critical roles in innate immunity, directly killing bacteria, fungi, and some viruses through membrane disruption. Q: How does LL-37 fight infection? A: LL-37 disrupts microbial membranes through electrostatic interaction with negatively charged lipid bilayers. Beyond direct antimicrobial activity, it modulates immune cell recruitment, inhibits biofilm formation, and promotes wound closure through angiogenesis and re-epithelialization. Q: What makes LL-37 unique among antimicrobial peptides? A: LL-37 is the sole human cathelicidin — unlike defensins which have multiple family members. Its dual role as both a direct antimicrobial agent and an immune modulator makes it a central player in the innate immune response and a promising research target. ## Interactive Tools - Research Calculator: https://ll37research.com/tools/dosing-calculator/ 88+ peptide protocols with reconstitution calculator, dosing phases, mechanism of action, half-life data, administration guidance, side effects, compatible stacks, per-protocol FAQs, and interactive syringe visualization. Supports blends with per-component injection breakdowns. ## Research Network (Sister Sites) - BPC-157 Research (bpc157research.us): BPC-157 Peptide Research — Mechanisms, Studies & Citations - KPV Research (kpvresearch.com): KPV Tripeptide Research — Anti-Inflammatory & Antimicrobial Science - Selank Research (selank-research.com): Selank Anxiolytic Peptide Research — BDNF & Immune Modulation - RETA Research (reta-research.com): RETA Peptide Research — Comprehensive Peptide Science & Analysis ## Quality Standards - All peptides referenced are 98%+ purity, HPLC verified - Independent third-party Certificates of Analysis (COAs) available - 100% USA-based: managed, tested, and shipped domestically - Cold-chain shipping with temperature-controlled logistics - Peer-reviewed content with direct PubMed citations ## Content Policy All content is for educational and research purposes only. Products referenced are for laboratory research use only (Research Use Only — RUO). Not approved by the FDA for human consumption, veterinary use, or any therapeutic purpose. All references to research findings describe preclinical laboratory studies, not clinical recommendations. 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