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Updated: Feb 14, 2026
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Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes
Published on: January 3, 2020
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Effects of microcystins on human polymorphonuclear leukocytes
Paula Kujbida1, Elaine Hatanaka, Ana Campa
1Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Brazil.
Biochemical and Biophysical Research Communications
|January 18, 2006
Summary
Microcystins (MCs), toxins from cyanobacteria, activate human neutrophils (PMNs) at low concentrations. This immune cell activation by MCs may explain their link to liver injury and tumor promotion.
Area of Science:
- Environmental toxicology
- Immunology
- Cellular biology
Background:
- Microcystins (MCs) are cyanobacterial cyclic heptapeptides linked to liver injury and tumor promotion.
- Cyanobacteria contamination in water reservoirs is a growing environmental concern.
Purpose of the Study:
- To investigate the effects of MC-LR and [Asp(3)]-MC-LR on human neutrophils (PMNs).
- To explore the potential mechanisms linking MC exposure to adverse health effects.
Main Methods:
- Human neutrophils (PMNs) were exposed to varying concentrations of MC-LR and [Asp(3)]-MC-LR.
- Chemotaxis, reactive oxygen species (ROS) production, phagocytosis, and Candida albicans killing assays were performed.
Main Results:
- Both MCs exhibited chemotactic activity and induced ROS production in PMNs.
- MCs enhanced Candida albicans phagocytosis, with MC-LR also increasing fungal killing.
- Observed effects occurred at concentrations below WHO recommendations for chronic exposure.
Conclusions:
- MCs modulate human neutrophil functions, including chemotaxis, ROS production, and phagocytosis.
- PMN activation and oxidative stress induced by MCs may contribute to liver injury and tumor promotion associated with long-term exposure.
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