.pdf" color="default" size="large" target="_blank" title="" animation_type="flash" animation_direction="down" animation_speed="0.1"]Download PDF Article[/fusion_button] [/s2If]
Comparison of Xenobiotic-mediated Cytotoxicity in Rat Cultured Hepatocytes and the V79 Chinese Hamster Lung Fibroblast Cell Line: Can Metabolically-activated Hepatotoxins be Identified by Selective Cytotoxicity to Hepatocytes?
Jeffrey R. Fry
Metabolism and Neurotoxicity: The Significance of Genetically Engineered Cell Lines and New Three-Dimensional Cell Cultures
Sandra Coecke, Chantra Eskes, Joanne Gartion, Erwin van Vliet, Agnieszka Kinsner, Alessia Bogni, Laura Raimondo, Nicholaos Parissis and Ingrid Langezaal
Until now, no methods have been validated for the determination of neurotoxic effects or for the evaluation of metabolism-mediated hazards of chemical substances. The current test guidelines are based on studies in vivo, involving animals exposed to the test substance. In the EU White Paper on a Strategy for a Future Chemicals Policy, which may result in up to 30,000 chemicals being screened for toxicity, the use of non-animal test methods is seen as essential and is encouraged. The aim of the present work was to demonstrate the significance of novel technologies, including the use of genetically engineered cell lines and three-dimensional cell culture techniques for direct application in the regulatory hazard-assessment process, with an emphasis on metabolism-mediated toxicity and neurotoxicity.
Heterologous Expression of Mouse Cytochrome P450 2e1 in V79 Cells: Construction and Characterisation of the Cell Line and Comparison with V79 Cell Lines Stably Expressing Rat P450 2E1 and Human P450 2E1
Ulrike Bernauer, Hansruedi Glatt, Barbara Heinrich-Hirsch, Yungang Liu, Eva Muckel, Bärbel Vieth and Ursula Gundert-Remy
A V79 Chinese hamster cell line was constructed for stable expression of mouse cytochrome P450 2e1 (Cyp2e1), as an addition to the existing cell battery consisting of cell lines stably expressing rat CYP2E1 and human CYP2E1 (V79 Cell Battery). The aim was to establish a cell battery that offers the in vitro possibility of investigating species-specific differences in the toxicity and metabolism of chemicals representing substrates for CYP2E1. The newly established cell line (V79m2E1) effectively expressed Cyp2e1 in the catalytically active form. The expression of catalytically active CYP2E1 in V79m2E1 cells was maintained over several months in culture, as demonstrated by Western Blotting and chlorzoxazone (CLX) 6-hydroxylase activity. The cells exhibited CLX 6-hydroxylase activity with a Km of 27.8μM/l and Vmax of 40pmol/mg protein/minute, compared with a Km of 28.2/28.6μM/l and a Vmax of 130/60pmol/mg protein/minute from V79r2E1/V79h2E1 cells. Furthermore, the CYP2E1-dependent mutagenicity of N-nitrosodimethylamine could be demonstrated in the V79m2E1 cells. Therefore, the new cell battery permits the interspecies comparison of CYP2E1-dependent toxicity and of metabolism of chemicals between humans and the two major rodent species the rat and the mouse that are usually used in classical toxicity studies.