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Exposure to silver nanoparticles affects viability and function of natural killer cells, mostly via the release of
Loretta Müller1, Selina K Steiner2, Laura Rodriguez-Lorenzo3
1University Children's Hospital Basel, Spitalstrasse 33, 4056, Basel, Switzerland. Loretta.mueller@ukbb.ch.
Abstract:
Natural killer (NK) cells play a crucial role in linking innate and adaptive immune responses, especially during viral infections and tumor surveillance. They have two major effector functions: the killing of stressed/abnormal cells and the release of cytokines. Their activity is regulated via inhibitory and activating surface receptors. At the same time that the production and use of engineered nanoparticles is steadily increasing, the risk for exposure to silver nanoparticles (AgNPs) from consumer products or biomedical applications is growing. Given this, we assessed the effects of 20-nm big AgNPs on NK cells, which represent an important part of the immune system. Our study involved overnight exposure of human blood NK cells to different concentrations of AgNPs, and silver (Ag) ion controls, and analyzing them for viability, surface receptor expression, intracellular markers, cytokine release, and killing potential. Exposure to AgNPs, but not to Ag ion controls, reduced the viability and the cytotoxic potential after polyriboinosinic-polyribocytidylic acid stimulation of NK cells and increased the expression of the inhibitory receptor CD159a. Exposure to AgNPs and Ag ion controls reduced the expression of the activating receptors CD335 and of CD16 and increased the expression of the activating receptor CD314. Overall, exposure to AgNPs changes NK cells' function and phenotype and may present a risk for modulating human immune responses, which should be further investigated.
Insights
Silver nanoparticles (AgNPs) impair natural killer (NK) cell function, reducing their viability and cytotoxic potential. This immune modulation by AgNPs warrants further investigation for potential health risks.
Area of Science:
- Immunology
- Nanotoxicology
- Cell Biology
Background:
- Natural killer (NK) cells are crucial for innate immunity, viral defense, and tumor surveillance.
- NK cell activity is regulated by surface receptors and involves cytokine release and cell killing.
- Increasing use of engineered nanoparticles, like silver nanoparticles (AgNPs), raises concerns about human exposure and potential health effects.
Purpose of the Study:
- To investigate the effects of 20-nm silver nanoparticles (AgNPs) on human NK cell viability, phenotype, and function.
- To compare the impact of AgNPs with silver ions (Ag+) on NK cells.
- To assess the potential immunomodulatory risks associated with AgNP exposure.
Main Methods:
- Human peripheral blood NK cells were exposed overnight to varying concentrations of AgNPs and Ag+ ions.
- Analysis included cell viability, surface receptor expression (inhibitory and activating), intracellular markers, cytokine release, and cytotoxic potential.
- Polyriboinosinic-polyribocytidylic acid stimulation was used to assess NK cell cytotoxic capacity.
Main Results:
- AgNP exposure, unlike Ag+ ions, significantly reduced NK cell viability and cytotoxic potential.
- AgNPs increased the expression of the inhibitory receptor CD159a.
- Both AgNPs and Ag+ ions altered the expression of activating receptors (CD335, CD16, CD314).
Conclusions:
- Exposure to AgNPs alters NK cell function and phenotype.
- AgNPs may pose a risk for modulating human immune responses.
- Further research is needed to fully understand the immunotoxicological implications of AgNP exposure.
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