The application of an in vitro micronucleus test in mouse fibroblast L929 cells

Publication date: Available online 11 May 2019Source: Mutation Research/Genetic Toxicology and Environmental MutagenesisAuthor(s): Ewa Drozd, Irena Bubko, Karolina Jaworska, Beata M. Gruber-BzuraAbstractThe MNa (in vitro the micronucleus assay) is recommended for studying genotoxicity of chemicals. However, no protocol is currently available for experiments with mouse fibroblast L929 cells. The aim of this study was to improve the scope of CBMNb (cytokinesis-block micronucleus) test. Optimization consisted of: selection of a non-cytotoxic concentration of cytokinesis blocker - cytoBc (cytochalasin B) and type and definition of the positive controls, verification of the efficacy of phenobarbital/5,6-benzoflavone as an S9 enzyme inducer as well as the identification of an optimal staining method. The compounds were tested in three exposure regimens: 6 h exposure with S9 activation followed by a 24 h recovery period, 6 h exposure followed by a 24 h recovery without metabolic activation of S9 and 30 h continuous exposure without S9. Different parameters, such as internal and interlaboratory reproducibility were investigated and criteria for test correctness were proposed. Higher MN rates were achieved using 1 μg/mL cytoBc as a cytokinesis blocker, and MMSd (methyl methanesulfonate), (250 μM), Cole (colchicine), (0.5 μM) and CPf (cyclophosphamide), (30 μM) as positive controls. In regard to the recommended S9 inducer, phenobarbital/5,6-benzoflavone was more effective as Aroclo...
Source: Mutation Research Genetic Toxicology and Environmental Mutagenesis - Category: Genetics & Stem Cells Source Type: research