LL-37

Tissue Repair & HealingResearch Only

Solid preclinical foundation with promising human observational data, but only 3 randomized trials limit clinical confidence. The peptide shows clear biological activity, but needs more rigorous human testing.

Wound care specialists and infectious disease researchers studying chronic wounds, biofilm infections, and immune dysfunction disorders.

FDA Status

Banned from Compounding

Since Mar 2024

Evidence

Moderate

Studies

30 total, 9 human

What is LL-37?

This human antimicrobial peptide belongs to the cathelicidin family and serves as part of our innate immune system's first line of defense. Researchers study it primarily for its dual role in fighting infections and accelerating tissue repair. Clinical investigators are particularly interested in its potential for treating chronic wounds and antibiotic-resistant infections.

LL-37 works by punching holes in bacterial cell membranes while simultaneously recruiting immune cells to infection sites. It also activates the STING pathway, a cellular alarm system that triggers antiviral responses and helps coordinate immune defenses. Think of it as both a direct weapon against pathogens and a communication signal that rallies the body's broader immune response.

What the Research Shows

While 30 total studies provide substantial background, the small number of randomized controlled trials (3) leaves significant gaps in understanding optimal dosing and clinical applications.

Thirty studies (20 human, 3 RCTs) demonstrate that LL-37 functions as an antimicrobial peptide with immunomodulatory properties, transporting cGAMP to activate STING signaling and enhance antiviral immunity, while also showing associations with T cell responses in acute coronary syndrome and plaque calcification. Limited randomized controlled trial evidence (3 RCTs) constrains definitive clinical conclusions, though observational data suggests LL-37 impacts multiple disease outcomes including potential roles in infant colic management and cardiovascular pathology.