Immune Peptides

LL-37

Commonly used for
Antimicrobial SupportWound HealingImmunity
What is it?
LL-37 is the only human cathelicidin antimicrobial peptide, naturally produced by immune cells and epithelial tissue as part of the innate immune system's first-line defense against bacteria, viruses, and fungi. It has antimicrobial, wound-healing, and immune-modulating properties.
Mechanism of action: Disrupts microbial cell membranes (broad-spectrum antimicrobial activity); Modulates innate immune signaling; Supports epithelial wound healing (preclinical)
What do people use it for?
Proposed indications: Antimicrobial support (preclinical); Wound healing (preclinical); Immune modulation
How is it used? / Dosing
Typical clinical dosing schedule: No established clinical dosing. Human therapeutic use has been limited to early-phase research.
Administration: Topical or injection (research settings) — No established clinical dosing
How does it compare?
Compare with:
How well does it work? / Evidence
? Emerging / limited evidence
An "emerging / limited evidence" rating means rigorous research hasn't caught up yet -- not that this peptide doesn't work. Many peptides in this category are newer or simply understudied rather than proven ineffective.
Evidence rating: ⭐⭐⭐☆☆ — Well-characterized antimicrobial activity in laboratory and preclinical studies; human clinical trial data for therapeutic use are limited.
Safety & side effects
Common side effects: Human safety profile remains incompletely characterized.
Serious risks: Unknown long-term safety with therapeutic administration.
Legal & regulatory status
Legal status: Not FDA-approved for human use. This is a research compound, not a medication — any use should only occur under the direction of a licensed healthcare provider, and its legal availability varies and changes frequently. Verify current status independently before considering use.
Regulatory status: Research peptide • Not FDA approved
Who should avoid it?
Contraindications: Not established. Avoid in:; Pregnancy; Active malignancy; Uncontrolled illness outside research settings
Pregnancy & breastfeeding: Avoid.
Research & references
Bals R, Wilson JM. (2003). Cathelicidins — a family of multifunctional antimicrobial peptides. Cellular and Molecular Life Sciences.