Susceptibility of clinical Staphylococcus aureus isolates to innate defense antimicrobial peptides.
Rieg. Siegbert S; Kaasch. Achim J AJ; Wehrle. Julian J; Hofmann. Silke C SC; Szymaniak-Vits. Magdalena M; Saborowski. Viola V; Jonas. Daniel D; Kalbacher. Hubert H; Seifert. Harald H; Kern. Winfried V WV
Key Findings
- LL‑37 showed a narrow, consistent range of minimum inhibitory concentrations across all S. aureus isolates.
- No significant difference in LL‑37 effectiveness between bacteria from infections and those from harmless colonization.
- Only a tiny, non‑significant trend toward better killing of colonizing strains was observed.
Practical Outcomes
- For DIY health enthusiasts, this means LL‑37 isn’t a magic bullet for preventing or treating S. aureus infections. The data don’t suggest any special dosing tricks or new protocols, so it’s not especially useful for everyday longevity or performance strategies.
Summary
The study looked at how the natural antimicrobial peptide LL‑37 (and a couple of others) kills Staphylococcus aureus bacteria taken from sick patients versus harmless carriers. It found that LL‑37 works about the same on all the bacteria, with no big differences in how much is needed to stop growth.
Abstract
Antimicrobial peptides (AMPs) are effector molecules of innate immunity. To determine whether AMP susceptibility of S. aureus varies according to different types of infection, 102 isolates from patients with S. aureus bacteremia or recurrent skin and soft tissue infection, and colonizing isolates were investigated. Using microbroth dilution assays we found a narrow range of MICs of human β-defensin-3, cathelicidin LL-37 and bovine indolicidin without significant differences between the groups. Colony-forming unit (CFU) assays revealed minor differences in bactericidal activity with slightly but not significantly higher CFU reduction in colonizing isolates. These data do not support a role for differential AMP susceptibility in vitro as a major determinant of S. aureus invasive infection.
Study Information
pubmed
2011
2011-04-05T00:00:00.000Z
10.1016/j.micinf.2011.03.010
4
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