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Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes
Published on: January 3, 2020
Staphylococcus aureus induces eosinophil cell death mediated by α-hemolysin
Lynne R Prince1, Kirstie J Graham, John Connolly
1Department of Infection and Immunity, University of Sheffield, Sheffield, United Kingdom. l.r.prince@sheffield.ac.uk
Plos One
|February 23, 2012
Summary
Staphylococcus aureus alpha-hemolysin (Hla) causes rapid eosinophil cell death, contributing to tissue damage in allergic diseases like atopic dermatitis and asthma. This finding highlights Hla as a key factor in S. aureus-mediated allergic inflammation.
Area of Science:
- Immunology
- Microbiology
- Dermatology
Background:
- Staphylococcus aureus is a pathogen that worsens allergic conditions such as atopic dermatitis, nasal polyps, and asthma.
- Eosinophils contribute to tissue damage and inflammation in these allergic disorders.
Purpose of the Study:
- To investigate the interaction between Staphylococcus aureus and eosinophils.
- To determine if S. aureus components contribute to eosinophil pathology in allergic diseases.
Main Methods:
- Cultured Staphylococcus aureus supernatants were applied to eosinophils and neutrophils.
- Strains deficient in accessory gene regulator (agr) and alpha-hemolysin (Hla) were used.
- Purified alpha-hemolysin was tested for its effect on eosinophils.
Main Results:
- S. aureus culture supernatants induced rapid eosinophil necrosis, but not neutrophil death.
- A strain deficient in agr, with reduced virulence factors including Hla, did not cause eosinophil death.
- Purified Hla induced concentration-dependent eosinophil apoptosis and necrosis.
Conclusions:
- Staphylococcus aureus alpha-hemolysin (Hla) induces aberrant eosinophil cell death in vitro.
- This Hla-mediated eosinophil death may exacerbate tissue injury in allergic diseases.
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