CORESTA SSPT, October 8-12, 2023, Cancun, Mexico
Emma Rothwell, Gina Smith, Sophie Martin and Michael Hollings;
Labcorp Early Development Laboratories Ltd., In Vitro Inhalation and In Vitro Toxicology, Harrogate, UK
Assays for the detection of chromosome damage in mammalian cells cultured in vitro are recommended in regulatory guidelines as a complement to Ames tests in a genotoxicity test battery.
An alternative to measuring structural aberrations in mitotic cells is to measure micronuclei. These are produced from whole chromosomes or acentric fragments that are unable to attach to the spindle at mitosis and appear during the next interphase as small similarly staining bodies adjacent to the main daughter nucleus. These are more easily counted than structural aberrations at mitosis and analysis can be performed rapidly on large numbers of cells. The in vitro micronucleus assay is a standard genetic toxicology test that has historically been run with a slide-scoring endpoint, which is labour intensive and
low throughput for testing multiple products. Flow cytometer analysis can be performed, with the use of additional stains, to measure micronucleus induction. In this project we utilised the Vitrocell® VC10® and VC1/7 smoking robot (Vitrocell Systems GmBH, Waldkirch, Germany) and high-throughput dilution system to perform air liquid interphase aerosol exposures on V79 cells grown on Transwells™.