LL-37 is a naturally occurring human peptide with broad antimicrobial activity against bacteria, fungi, and viruses, plus emerging evidence of anti-cancer effects through immune modulation and direct tumor cell killing.
Triple-threat peptideLL-37 demonstrates activity against bacteria, fungi, and viruses through distinct mechanisms, plus anti-cancer properties
What the researchers found
LL-37, the only human cathelicidin antimicrobial peptide, has demonstrated activity across three domains of infection — bacterial, fungal, and viral — through distinct mechanisms. Against bacteria, it disrupts cell membranes. Against fungi, it inhibits growth. Against viruses, it interferes with replication. Additionally, LL-37 shows immunomodulatory effects and direct cytotoxicity against cancer cells, positioning it as a potential multi-purpose therapeutic molecule.
Why it matters
As antibiotic resistance grows, there's urgent need for alternatives. LL-37 is produced naturally by the human body, making it a well-tolerated starting point for drug development. Its ability to fight infections across multiple pathogen types while also modulating immune responses against cancer makes it unusually versatile compared to conventional antibiotics that target only bacteria.
How the study worked
This is a narrative review article that synthesizes published research on LL-37's antimicrobial and anti-cancer properties. The authors surveyed the literature on LL-37's mechanisms of action against bacteria, fungi, viruses, and cancer cells.
Who was studied
Not applicable (review article synthesizing existing research)
What this study cannot tell us
As a review article, this paper does not present original experimental data. Most LL-37 research has been preclinical (lab and animal studies), with limited human clinical trial data. The therapeutic potential described is largely theoretical and would require extensive clinical testing.
How to read the evidence
This is a narrative review article synthesizing existing research. It provides a comprehensive overview but does not present new experimental data or perform systematic analysis.
When this study was published
Published in 2025, this is a current review that captures the latest understanding of LL-37's therapeutic potential across infections and cancer.
The bigger picture
With antibiotic-resistant infections killing over a million people annually, the search for new antimicrobial strategies has intensified. LL-37 stands out because it's already part of human innate immunity, has broad-spectrum activity, and works through membrane disruption — a mechanism that bacteria find much harder to develop resistance against. Its additional anti-cancer properties make it one of the most studied antimicrobial peptides for therapeutic development.
Questions still open
- Can LL-37 or its derivatives be formulated into practical drugs that maintain stability and potency in the body?
- Will LL-37's anti-cancer effects hold up in human clinical trials, or are they limited to laboratory settings?
- Could combining LL-37 with conventional antibiotics overcome drug-resistant infections?
Common questions
What is LL-37 and where does it come from?
Can LL-37 really fight cancer?
Read the original research
LL-37, the master antimicrobial peptide, its multifaceted role from combating infections to cancer immunity.
International journal of antimicrobial agents, 65(1), 107398
Citation
Keshri, Anand K; Rawat, Suraj S; Chaudhary, Anubha; Sharma, Swati; Kapoor, Ananya; Mehra, Parul; Kaur, Rimanpreet; Mishra, Amit; Prasad, Amit. (2025). LL-37, the master antimicrobial peptide, its multifaceted role from combating infections to cancer immunity.. International journal of antimicrobial agents, 65(1), 107398. https://doi.org/10.1016/j.ijantimicag.2024.107398