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Updated: May 27, 2026
12:27
Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes
Published on: January 3, 2020
Staphylococcus aureus produces membrane-derived vesicles that induce host cell death
Mamata Gurung1, Dong Chan Moon, Chi Won Choi
1Department of Microbiology, Kyungpook National University School of Medicine, Daegu, Korea.
Plos One
|November 25, 2011
Summary
Staphylococcus aureus produces membrane-derived vesicles (MVs) that deliver effector proteins to host cells. These MVs induce apoptosis, highlighting their role in gram-positive bacterial pathogenesis.
Area of Science:
- Microbiology
- Cell Biology
- Bacterial Pathogenesis
Background:
- Gram-negative bacteria utilize outer membrane vesicles for virulence factor delivery.
- Limited knowledge exists regarding membrane-derived vesicles (MVs) in gram-positive bacteria.
Purpose of the Study:
- To investigate MV production by Staphylococcus aureus.
- To determine the role of S. aureus MVs in host cell interaction and cytotoxicity.
Main Methods:
- Analysis of MV production in vitro and in vivo.
- Proteomic analysis of S. aureus MVs.
- Investigation of MV-host cell interaction and cytotoxicity assays.
Main Results:
- S. aureus produces spherical nanovesicles (MVs) in vitro and during infection.
- Proteomic analysis identified 143 proteins in S. aureus MVs.
- MVs deliver protein A to host cells via cholesterol-rich domains, inducing apoptosis.
Conclusions:
- S. aureus MVs are actively produced and mediate effector molecule delivery.
- Intact MVs are crucial for cytotoxicity, inducing apoptosis in host cells.
- This study establishes S. aureus MVs as significant vehicles for bacterial pathogenesis.
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