ALTEX :: Alternatives to Animal Experiments

2003, VOLUME 3

V79 Chinese Hamster Cells Genetically Engineered for Polymorphic Cytochrome P450 2D6 and their Predictive Value for Humans

Niels Krebsfaenger1, Thomas E. Mürdter2, Ulrich M. Zanger2, Michel F. Eichelbaum2 and Johannes Doehmer1

1GenPharmTox BioTech AG, D-Planegg/Martinsried; 2Dr Margarete Fischer-Bosch-Institute for Clinical Pharmacology, D-Stuttgart

SUMMARY

With more than 30 genetic variants human cytochrome P450 2D6 (CYP2D6) presents the most extensive variation among all cytochromes P450. At the same time, roughly 30% of all drugs are metabolised by CYP2D6. Therefore, V79 Chinese hamster cells were genetically engineered for the genetic variants *1, *2, *9, *10, and *17 encoding active enzymes. These cells are to be used to understand and to predict variant-dependent metabolism of drugs and drug candidates. The V79-derived cell lines were extensively characterised for stable expression of mRNA, for enzyme activity using bufuralol hydroxylation, for CYP content by CO difference spectra, and for protein distribution and cellular location by in situ immunofluorescence. Based on these results, CYP-mediated metabolism of tamoxifen was investigated.

Keywords: cytochrome P450 2D6, V79 Chinese hamster cells, polymorphism, bufuralol, tamoxifen