LL-37 Peptide

PEPTIDES+ MEMBERS ONLY

INDICATIONS FOR USE

LL-37 is primarily used in dermatology for wound healing, reducing inflammation, and treating chronic skin conditions such as eczema, psoriasis, and acne. It is also employed for hair restoration, as it improves scalp health and stimulates hair follicle activity. LL-37’s antimicrobial properties make it an effective agent against skin infections and resistant bacterial strains.

ROUTE OF ADMINISTRATION

  • Topical: Applied directly to the skin or scalp as a cream, serum, or gel.

  • Injectable: Administered subcutaneously near the affected area or target site for deeper tissue effects.

FORMULATIONS AND PRICING

FormulationPrice
5mg multi-dose vial (1mg/mL x 5mL)$135

COMMON INITIAL DOSING REGIMENS

  • Topical: Applied to the affected area 1–2 times daily. Concentrations in topical formulations are often customized but typically range from 0.1% to 0.5%.

  • Injectable: Standard dosing ranges from 100–200 µg per injection, administered 2–3 times weekly, depending on the condition being treated, such as skin repair or hair restoration.

MECHANISM OF ACTION

  • LL-37 is a cathelicidin-derived peptide that serves as a key component of the innate immune system. It exhibits the following mechanisms:

  • Antimicrobial Activity: Broad-spectrum efficacy against bacteria (Gram-positive and Gram-negative), viruses, and fungi. LL-37 disrupts microbial membranes, preventing infections in wounds or irritated skin.

  • Anti-Inflammatory Effects: Regulates pro-inflammatory cytokine release, reducing redness, swelling, and irritation in conditions like acne and psoriasis.

  • Wound Healing: Promotes re-epithelialization by enhancing keratinocyte and fibroblast proliferation. LL-37 also stimulates angiogenesis, improving oxygen and nutrient delivery to the wound site.

  • Hair Growth: Enhances dermal papilla cell activity and follicle stimulation by reducing inflammation and improving blood flow.

COMMON SIDE EFFECTS

  • Topical: Mild itching, erythema, or burning sensation at the application site. Rarely, patients may experience worsening of pre-existing skin conditions due to sensitivity to the active ingredient.

  • Injectable: Localized reactions such as swelling, tenderness, or bruising at the injection site. Rare systemic effects include fatigue, headache, or nausea.

  • Severe Effects: Prolonged use may lead to over-suppression of local inflammation, potentially delaying wound healing in certain cases. Rare hypersensitivity reactions have been reported.

CONTRAINDICATIONS

  • Absolute: Hypersensitivity to LL-37 or any excipients in the formulation.

  • Relative: Patients with autoimmune skin conditions should use LL-37 cautiously, as its immune-modulating effects may exacerbate certain autoimmune responses. Individuals with active systemic infections should consult their healthcare provider before using LL-37 due to potential immunomodulatory interactions.

ADDITIONAL NOTES ON EFFICACY

  • LL-37 is a versatile peptide with applications extending beyond dermatology to systemic immune support and inflammation control. In hair restoration protocols, it is often paired with growth factors or other peptides like GHK-Cu to maximize follicular stimulation.

MORE INFORMATION

  • FDA Safety Data Sheet not available (experimental peptide).

  • Vandamme D. A comprehensive summary of LL-37, the factotum human cathelicidin peptide. Cell Immunol. 2012 [PubMed Link]

  • van der Does AM. Induction of the human cathelicidin LL-37 as a novel treatment against bacterial infections. J Leukoc Biol. 2012 [PubMed Link]

  • Nijnik A. The roles of cathelicidin LL-37 in immune defences and novel clinical applications. Curr Opin Hematol. 2009 [PubMed Link]

  • Kahlenberg JM. Little peptide, big effects: the role of LL-37 in inflammation and autoimmune disease. J Immunol. 2013 [PubMed Link]

  • Chen K. The potentials of short fragments of human anti-microbial peptide LL-37 as a novel therapeutic modality for diseases. Front Biosci (Landmark Ed). 2021[PubMed Link]

  • Alexandre-Ramos DS. LL-37 treatment on human peripheral blood mononuclear cells modulates immune response and promotes regulatory T-cells generation. Biomed Pharmacother. 2018 [PubMed Link]

  • Tjabringa GS. The human cathelicidin LL-37: a multifunctional peptide involved in infection and inflammation in the lung. Pulm Pharmacol Ther. 2005 [PubMed Link]

  • Wang G. Design of Antimicrobial Peptides: Progress Made with Human Cathelicidin LL-37. Adv Exp Med Biol. 2019 [PubMed Link]

  • Acen EL. Impact of vitamin D status and cathelicidin antimicrobial peptide on adults with active pulmonary TB globally: A systematic review and meta-analysis. PLoS One. 2021 [PubMed Link]

  • Ho J. Pathological Role and Diagnostic Value of Endogenous Host Defense Peptides in Adult and Neonatal Sepsis: A Systematic Review. Shock. 2017 [PubMed Link]

  • Aloul KM. Upregulating Human Cathelicidin Antimicrobial Peptide LL-37 Expression May Prevent Severe COVID-19 Inflammatory Responses and Reduce Microthrombosis. Front Immunol. 2022 [PubMed Link]

  • Piktel E. The Role of Cathelicidin LL-37 in Cancer Development. Arch Immunol Ther Exp (Warsz). 2016 [PubMed Link]

  • Sánchez-Peña FJ, Romero-Tlalolini MLÁ, Torres-Aguilar H, et al. LL-37 Triggers Antimicrobial Activity in Human Platelets. Int J Mol Sci. 2023 [PubMed Link]