p450 - publications
Evaluation of OATP1B1 and CYP3A4 activities in primary human hepatocytes and HepaRG cells cultured in a dynamic three-dimensional bioreactor system.
J Pharmacol Exp Ther. 2012 Jul 12;
Authors: Ulvestad M, Darnell M, Molden E, Ellis E, Asberg A, Andersson TB
Long-term stability of liver cell functions is a major challenge when studying hepatic drug transport, metabolism and toxicity in vitro. The aim of the present study was to investigate the OATP1B1 and CYP3A4 activities in fresh primary human hepatocytes and differentiated cryopreserved HepaRG cells when cultured in a 3D bioreactor system. The OATP1B1 activity was determined by loss from media experiments of [3H]-estradiol-17β-D-glucuronide ([3H]-E17βG) and atorvastatin acid (ATA) for up to 7 days in culture. ATA metabolite formation was determined at day 3 to 4 to evaluate the CYP3A4 activity. Overall, the results showed that freshly isolated human hepatocytes inoculated in the bioreactor retained OATP1B1 activity for at least 7 days, while in HepaRG cells, no OATP1B1 activity was observed beyond day 2. The activity data were in agreement with immunohistochemical stainings, which showed that OATP1B1 protein expression was preserved for at least 9 days in fresh human hepatocytes, while OATP1B1 was markedly lower expressed in HepaRG cells after 9 days in culture. Fresh human hepatocytes and HepaRG cells exhibited similar CYP3A4 activity in bioreactor culture, and immunohistochemical stainings supported these findings. Activity and mRNA expression of OATP1B1 and CYP3A4 in primary human hepatocytes compared to HepaRG cells in fresh suspensions were in agreement with data obtained in bioreactor culture. In conclusion, freshly isolated human hepatocytes cultured in a 3D bioreactor system, preserves both OATP1B1 and CYP3A4 activities, allowing long-term in vitro studies on drug disposition and toxicity.
PMID: 22789711 [PubMed - as supplied by publisher]