New Research Validates Miniaturization of Micronucleus Testing for Genotoxicity by 96-Well Flow Cytometry

Gentronix, specialists in genotoxicity testing, has collaborated with Litron Laboratories, Janssen Pharmaceuticals and the Novartis Institute for Biomedical Research, to publish a new peer-reviewed research paper that validates a flow cytometric method of scoring 96-well plate micronucleus testing (MNT) for in vitro screening of compounds for genotoxicity hazards.

The inclusion of the micronucleus test in the recent ICH revision to the guidelines on genotoxicity is evidence of the benefits of using this assay as an alternative to the traditional Chromosome Aberration test. In addition to the assay’s superior ability to detect aneugens, the use of double staining in the flow cytometry protocol means that apoptotic or necrotic cells can be identified and excluded from the test, thereby guarding against ‘irrelevant positive’ results. Further benefits include both an increase in the throughput of the assay and a reduction in the amount of compound required.

This research, published in Experimental and Molecular Mutagenesis, describes the optimization of the protocol and includes an inter-laboratory assessment of the assay’s transferability and reproducibility. The conclusion of the paper was that the 96-well plate-based MicroFlow® micronucleus test is transferrable across laboratories, and the high information content provided by flow cytometry helps to guard against irrelevant positive results arising from overt toxicity.

Gentronix now provides in vitro MicroFlow® micronucleus testing as a service to its clients, and is a distributor of the Litron Laboratory kits throughout Europe.

Steve Beasley, Commercial Director at Gentronix comments: “Detailed analysis and method validation are central to our work here at Gentronix, and we are pleased to be part of this work to extend the performance and range of genotoxicity assays available.”

Drew Tometsko, Director of Operations at Litron Laboratories said: “This validation project comes at a time when the field of genetic toxicology is recognizing the limitations that exist with standard testing methods. These data show how the industry is not simply working to overcome the deficiencies, but is instead developing powerful new methods that significantly advance the state-of-the-art.”