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An Automated Method to Perform The In Vitro Micronucleus Assay using Multispectral Imaging Flow Cytometry
Published on: May 13, 2019
A flow cytometry based in vitro micronucleus assay in TK6 cells--validation using early stage pharmaceutical
Magdalena Lukamowicz1, Katherine Woodward, Micheline Kirsch-Volders
1Novartis Institutes for Biomedical Research, Preclinical Safety, Genetic Toxicology and Safety Pharmacology, Basel, Switzerland. magdalena.lukamowicz@novartis.com
Environmental and Molecular Mutagenesis
|October 22, 2010
Summary
The flow cytometry micronucleus test (MNT) offers reliable genotoxicity assessment. Validation confirmed its accuracy, comparable to microscopy, for pharmaceutical drug development.
Area of Science:
- Toxicology
- Genetics
- Biotechnology
Background:
- The micronucleus test (MNT) is crucial for identifying genotoxic compounds.
- Potential sources of error in MNT include apoptosis underestimation, p53 status, and cytotoxicity assay selection.
- Flow cytometry offers a potential improvement for MNT accuracy.
Purpose of the Study:
- To validate the flow cytometry-based micronucleus test (MNT).
- To identify the most reliable cytotoxicity assay for selecting the top dose in MNT.
- To compare flow cytometry MNT with traditional microscopy methods.
Main Methods:
- Evaluated five cytotoxicity assays for top dose selection: relative cell count, population doubling, trypan blue, nuclei/beads ratio, and ethidium monoazide.
- Compared micronuclei induction in TK6 cells using microscopy and flow cytometry.
- Tested reference and internal compounds with varying genotoxic profiles, including those requiring metabolic activation.
Main Results:
- The nuclei/beads ratio was the most reliable cytotoxicity assay, outperforming relative cell count.
- Flow cytometry MNT showed good correlation with microscopy-based MNT results.
- The method accurately assessed genotoxic effects for a range of compounds.
Conclusions:
- Flow cytometry MNT is a reliable method for routine genotoxicity testing in pharmaceutical development.
- The nuclei/beads ratio is recommended for cytotoxicity assessment in MNT.
- Further validation and miniaturization of flow cytometry MNT are warranted.
