Adipose Stem Cells Kill LL-37-Resistant Bacteria: Overcoming Antimicrobial Peptide Resistance | Research

The takeaway

Human adipose-derived stem cells showed antibacterial effects against bacteria that had developed resistance to the antimicrobial peptide LL-37, revealing a cellular defense mechanism against peptide resistance.

Resistance overcome
Adipose stem cells killed bacteria that had become resistant to the antimicrobial peptide LL-37, using alternative defense mechanisms

What the researchers found

Human adipose-derived stem cells effectively killed LL-37-resistant bacteria through alternative antimicrobial mechanisms, overcoming cathelicidin resistance.

Why it matters

Antimicrobial peptide resistance is an emerging concern. Discovering that stem cells provide backup antimicrobial defense against peptide-resistant bacteria reveals new approaches to treating resistant infections.

The numbers in context

Three bacterial species tested: Pseudomonas aeruginosa, Proteus mirabilis, and MRSA. All had evolved LL-37 resistance.

How the study worked

Generated LL-37-resistant bacterial strains. Tested adipose-derived stem cell antibacterial effects against resistant and sensitive bacteria. Analyzed antimicrobial mechanisms.

Who was studied

In vitro: human adipose-derived stem cells vs. LL-37-resistant P. aeruginosa, P. mirabilis, and MRSA

What this study cannot tell us

In vitro study. The clinical relevance of LL-37 resistance in wound infections needs evaluation. ADSCs are not practical as direct therapeutic agents for infections.

How to read the evidence

Preliminary evidence: in vitro demonstration of stem cell antimicrobial activity against peptide-resistant bacteria.

When this study was published

Published in 2025. Addresses the emerging challenge of antimicrobial peptide resistance.

The bigger picture

As antimicrobial peptides advance toward clinical use, understanding resistance mechanisms and backup defenses becomes essential. This study shows the innate immune system has redundant layers — even if bacteria resist one antimicrobial peptide, other cellular defenses can compensate.

Questions still open

What specific antimicrobial mechanisms do ADSCs use against LL-37-resistant bacteria?
Could ADSC-derived factors be developed as treatments for peptide-resistant infections?
How common is LL-37 resistance in clinical wound infections?

Common questions

Can bacteria resist antimicrobial peptides?

Yes — some bacteria can develop resistance to LL-37 and other antimicrobial peptides, similar to antibiotic resistance. This study shows the body has backup defenses: adipose stem cells can still kill these resistant bacteria through different mechanisms.

Could stem cells treat infections?

Not directly as a clinical treatment, but understanding how stem cells kill peptide-resistant bacteria could lead to new antimicrobial approaches. The stem cells' antimicrobial factors could potentially be identified and developed as treatments.

Read the original research

The antibacterial effect of human adipose-derived stem cells on LL-37-resistant bacteria.

PloS one, 20(10), e0333647

View on PubMed ↗Publisher’s paper ↗

Citation

Afzal Haghjoo, Parisa; Mojtahedi, Ali; Ansar, Malek Moien; Ansar, Malek Masoud; Danesh Mobarhan, Safieh. (2025). The antibacterial effect of human adipose-derived stem cells on LL-37-resistant bacteria.. PloS one, 20(10), e0333647. https://doi.org/10.1371/journal.pone.0333647