Characterisation Of The Induction Of Cytochrome P450 Enzymes In Primary Cultures Of Human Hepatocytes

The induction of drug metabolising enzymes e.g. cytochrome P450s (CYPs), in vivo, by drugs, can attenuate the desired clinical effect or can lead to potential pharmacological effects and/or toxicity. The ability to screen for these undesirable characteristics or an early stage of drug development ex vivo is clearly an advantage economically and ethically. Validated methods for the determination of the enzyme activities of a range of CYPs have been established at Covance. This work aims to develop a real time quantitative polymerase chain reaction (RT-QPCR) assay to monitor the induction of individual CYPs in human hepatocytes samples by quantitatively measuring mRNA compared to protein. We have designed Taqman primers and probes for human CYP3A4, CYP2B6 and CYP1A2 and the RT-QPCR method has been developed and validated. Using the validated methods described, the relationship between mRNA expression and enzyme activity will be determined in fresh human hepatocytes.