SFTG international collaborative study on in vitro micronucleus test

Abstract

In this report, results are presented from an international study of the in vitro micronucleus assay using mouse lymphoma L5178Y cells. This study was coordinated by an organizing committee supported by the SFTG (the French branch of the European Environmental Mutagen Society). Test chemicals included mannitol, bleomycin, 5-fluorouracil, colchicine and griseofulvin. Mitomycin C was used as a positive control. Each chemical was evaluated in at least two laboratories following a variety of different protocols (short and long exposures, varying recovery times, with and without cytochalasin B) in order to help determine a standard protocol for routine testing in mouse lymphoma L5178Y cells. Mannitol was the only exception, being tested in only one laboratory. Mannitol was negative, while bleomycin induced a concentration-dependent increase in micronucleated cells. Equivocal results were obtained for 5-fluorouracil, colchicine and griseofulvin. High levels of cytotoxicity interfered with the assessment of aneuploidy for colchicine and griseofulvin, preventing the ability to obtain clear results in all the treatment schedules. Experiments with 5-fluorouracil, colchicine and griseofulvin showed that both short and long treatment times are required as each compound was detected using one or more treatment protocol. No clear differences were seen in the sensitivity or accuracy of the responses in the presence of absence of cytochalasin B. It was also found that a recovery period may help to detect compounds which induce a genotoxicity associated to a reduction in cell number or cell proliferation. Overall, the results of the present study show that mouse lymphoma L5178Y cells are suitable for the in vitro micronucleus assay.

Genotoxicity Assessment of Erythritol by Using Short-term Assay

“…The micronucleus assay was performed according to Kirsch-Volders et al . (11) with modifications (12). The L5178Y tk +/− cell line (ATCC #CRL-9518, subclone 3.7.2-C) used in this study was provided by ATCC.…”

Automation of the in vitro micronucleus assay using the Imagestream® imaging flow cytometer

“…Several studies have been performed to test the in vitro MN assay using a number of different cell types including human peripheral blood lymphocytes 14, 49, Chinese Hamster Ovary cells 13, Chinese Hamster Lung cells 17, and mouse lymphoma L5178Y cells 16, 48, 62, demonstrating positive results for many test agents. Therefore, the assay should be performed on the ISX using additional cell types and chemical agents to develop applicable sample processing methods and to demonstrate the adaptability of the method.…”

“…In recent years, several protocols and exposure schedules to perform the MN assay have been developed and validated in a number of recommended cell types 9, 10, 11, 12. Current forms of the assay are able to detect the presence of clastogens and aneugens in both rodent and human derived cell lines as well as in human peripheral blood lymphocytes 13, 14, 15, 16, 17.…”

5‐Fluorouracil and its active metabolite FdUMP cause DNA damage in human SW620 colon adenocarcinoma cell line

“…For the clastogenicity assay, 5 × 10 5 cells were seeded on six-well plates and incubated for 24 h. Treatments were performed for 48 h. Procedures of harvesting and fixing cells were based on Oliver et al (2006). Cells were harvested with trypsin, hypotonized with sodium citrate 1% and fixed with methanol acetic acid (3 : 1) prior to transferring to slides.…”