The Humanized Liver and Gut CYP3A4 Mouse was developed by Alfred Schinkel at the Netherlands Cancer Institute. The model was generated by targeting of the Cyp3a13 gene in 129P2/OlaHsd-derived E14 ES cells to replace the putative promoter region and exons 1 and 2 with a Pgk-hygromycin cassette. Targeted ES cells were injected into blastocysts. Resultant chimeras were backcrossed to FVB/N for at least seven generations. To generate the cluster deletion, the intronic sequence between exon 2 and 3 of Cyp3a57 was replaced with a neo cassette containing a loxP site, and a hygromycin cassette with a loxP site was inserted downstream of the Cyp3a59 gene in 129P2/OlaHsd-derived E14 ES cells through gene targeting. Transfection of the ES cells with cre recombinase resulted in the deletion of Cyp3a57, Cyp3a16, Cyp3a41, Cyp3a44, Cyp3a11, Cyp3a25 and Cyp3a59. The targeted ES cells were injected into blastocysts. Resultant chimeras were backcrossed two generations to FVB/N. Mice with the cluster deletion were then backcrossed to the Cyp3a13 targeted mutation line for at least four generations to generate a model with disruption or deletion of all eight full-length mouse Cyp3a genes. The Tg(APOE-CYP3A4)A1Ahs transgene was generated by microinjection into FVB/N zygotes. The Tg(Vil1-CYP3A4)1Ahs transgene was generated by microinjection into FVB/N zygotes. The two transgenes were combined into a single line through crossbreeding, and then the Cyp3a knockout line was backcrossed to that Tg(APOE-CYP3A4)A1Ahs Tg(Vil1-CYP3A4)1Ahs line for at least three generations. Taconic received stock in 2008, and the line was embryo transfer derived by mating male and female mice homozygous for both targeted regions and homozygous for both transgenes. The line was maintained by mating male and females homozygous for the Cyp3a13 disruption, the cluster deletion and the two transgenes.
van Herwaarden AE, Smit JW, Sparidans RW, Wagenaar E, van der Kruijssen CM, Schellens JH, Beijnen JH, Schinkel AH. (2005) Midazolam and cyclosporin a metabolism in transgenic mice with liver-specific expression of human CYP3A4. Drug Metab Dispos 33(7):892-5.
van Herwaarden AE, Wagenaar E, van der Kruijssen CM, van Waterschoot RA, Smit JW, Song JY, van der Valk MA, van Tellingen O, van der Hoorn JW, Rosing H, Beijnen JH, Schinkel AH. (2007) Knockout of cytochrome P450 3A yields new mouse models for understanding xenobiotic metabolism. J Clin Invest 117(11):3583-92.
van Waterschoot RAB, Rooswinkel RW, Sparidans RW, van Herwaarden AE, Beijnen JH, Schinkel AH (2009). Inhibition and stimulation of intestinal and hepatic CYP3A activity: studies in humanized CYP3A4 transgenic mice using triazolam. Drug Metab Disp 37:2305-2313.
van Waterschoot RAB, Rooswinkel RW, Waagenar E, van der Kruijssen CMM, van Herwaarden AE, Schinkel AH (2009). Intestinal cytochrome P450 3A plays an important role in the regulation of detoxifying systems in the liver. FASEB J 23(1): 224-231.
van Waterschoot RAB, ter Heine R, Waagenar E, van der Kruijssen CMM, Rooswinkel RW, Huitema ADR, Beijnen JH, Schinkel AH (2010). Effects of cytochrome P450 3A (CYP3A) and the drug transporters P-glycoprotein (MDR1/ABCB1) and MRP2 (ABCC2) on the pharmacokinetics of lopinavir. Br J Pharmacol 160(5):1224-1233.