66 research outputs found
Simultaneous Measurement of Benzo[a]pyrene-induced Pig-a and lacZ Mutations, Micronuclei and DNA Adducts in Muta™ Mouse
In this study we compared the response of the Pig-a gene mutation assay to that of the lacZ transgenic rodent mutation assay, and demonstrated that multiple endpoints can be measured in a 28-day repeat dose study. Muta™Mouse were dosed daily for 28 days with benzo[a]pyrene (BaP; 0, 25, 50 and 75 mg/kg body weight/day) by oral gavage. Micronucleus (MN) frequency was determined in reticulocytes (RETs) 48 hr following the last dose. 72 h following the last dose, mice were euthanized, and tissues (glandular stomach, small intestine, bone marrow and liver) were collected for lacZ mutation and DNA adduct analysis, and blood was evaluated for Pig-a mutants. BaP-derived DNA adducts were detected in all tissues examined and significant dose-dependent increases in mutant Pig-a phenotypes (i.e., RETCD24- and RBC CD24-) and lacZ mutants were observed. We estimate that mutagenic efficiency (i.e., rate of conversion of adducts into mutations) was much lower for Pig-a compared to lacZ, and speculate that this difference is likely explained by differences in repair capacity between the gene targets, and differences in the cell populations sampled for Pig-a versus lacZ. The BaP doubling doses for both gene targets, however, were comparable, suggesting that similar mechanisms are involved in the accumulation of gene mutations. Significant dose-related increases in % MN were also observed; however, the doubling dose was considerably higher for this endpoint. The similarity in dose response kinetics of Pig-a and lacZ provides further evidence for the mutational origin of glycosylphosphatidylinositol (GPI)-anchor deficiencies detected in the Pig-a assay. Environ. Mol. Mutagen. 2011. © 2011 Wiley-Liss, Inc
Absence of in vivo mutagenicity of multi-walled carbon nanotubes in single intratracheal instillation study using F344 gpt delta rats
Manifestation and persistence of Pig-a mutant red blood cells in C57BL/6 mice following single and split doses of N-ethyl-N-nitrosourea
Further development of the rat Pig-a mutation assay: Measuring rat Pig-a mutant bone marrow erythroids and a high throughput assay for mutant peripheral blood reticulocytes
When pigs fly: Immunomagnetic separation facilitates rapid determination of Pig-a mutant frequency by flow cytometric analysis
The frequency of Pig-a mutant red blood cells in rats exposed in utero to N-ethyl-N-nitrosourea
International Pig-a gene mutation assay trial: Evaluation of transferability across 14 laboratories
Interlaboratory Pig-a gene mutation assay trial: Studies of 1,3-propane sultone with immunomagnetic enrichment of mutant erythrocytes
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