title: The rat Pig-a assay using an erythroid HIS49 antibody in a single dose study of isopropyl p-toluenesulfonate.
abstract: As part of a collaborative study in the Mammalian Mutagenicity Study group of the Japanese Environmental Mutagen Society, we evaluated the in vivo mutagenicity of isopropyl p-toluenesulfonate (IPTS) using a peripheral blood Pig-a assay in rats. Pig-a mutant frequency (MF) data was obtained for both red blood cells (RBCs) and reticulocytes (RETs) at 1, 2 and 4 weeks after a single oral administration of IPTS at doses of 125, 250, or 500mg/kg. The results of the RBC Pig-a assay demonstrated that both the 250 and 500mg/kg treatment groups showed significant increases in Pig-a MF only at 4 weeks after IPTS treatment. In comparison, the PIGRET assay showed a clear and dose-related increase in Pig-a MF at 1 week after treatment, with a continuous increase until 4 weeks after treatment observed in the highest dose group. These results indicate that the both the RBC Pig-a assay and PIGRET assay can detect in vivo IPTS mutagenicity under a single dosing protocol. In particular, the PIGRET assay, which uses magnetic enrichment to analyze greater numbers of RETs in a high-throughput manner, showed an increase in Pig-a MF earlier than the RBC Pig-a assay. The PIGRET assay is also considered to be more sensitive than the RBC Pig-a assay because it exhibits a low spontaneous Pig-a MF. For this reason, the PIGRET assay clearly identified small increases in Pig-a MF as significant at the lower doses than in the RBC Pig-a assay under the conditions in this study.
authors.affiliation: Pharmaceutical Development Research Laboratories, Teijin Institute for Bio-Medical Research, Teijin Pharma Limited, 4-3-2 Asahigaoka, Hino-shi, Tokyo 191-8512, Japan. Electronic address: s.chikura@teijin.co.jp.
authors.forename: Satsuki
authors.initials: S
authors.lastname: Chikura
authors.affiliation: Pharmaceutical Development Research Laboratories, Teijin Institute for Bio-Medical Research, Teijin Pharma Limited, 4-3-2 Asahigaoka, Hino-shi, Tokyo 191-8512, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Okada
authors.affiliation: Pharmaceutical Development Research Laboratories, Teijin Institute for Bio-Medical Research, Teijin Pharma Limited, 4-3-2 Asahigaoka, Hino-shi, Tokyo 191-8512, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Kimoto
authors.affiliation: Pharmaceutical Development Research Laboratories, Teijin Institute for Bio-Medical Research, Teijin Pharma Limited, 4-3-2 Asahigaoka, Hino-shi, Tokyo 191-8512, Japan.
authors.forename: Hideshi
authors.initials: H
authors.lastname: Kaneko
authors.affiliation: Pharmaceutical Development Research Laboratories, Teijin Institute for Bio-Medical Research, Teijin Pharma Limited, 4-3-2 Asahigaoka, Hino-shi, Tokyo 191-8512, Japan.
authors.forename: Daishiro
authors.initials: D
authors.lastname: Miura
authors.affiliation: Pharmaceutical Development Research Laboratories, Teijin Institute for Bio-Medical Research, Teijin Pharma Limited, 4-3-2 Asahigaoka, Hino-shi, Tokyo 191-8512, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Kasahara
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology*; D001557:Benzenesulfonates / Q000633:toxicity*; D001835:Body Weight; D004912:Erythrocytes / Q000187:drug effects / Q000276:immunology*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D009152:Mutagenicity Tests / Q000379:methods*; D009153:Mutagens / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000906:Antibodies; D001557:Benzenesulfonates; D008565:Membrane Proteins; D009153:Mutagens; C080086:phosphatidylinositol glycan-class A protein; C029501:4-toluenesulfonic acid
keywords: Flow cytometry; Gene mutation; IPTS; Pig-a assay