Microsoft Word - 88124461-file00

The human liver cell line HepaRG has been recognized as a promising source for in vitro testing of metabolism and toxicity of compounds. However, currently the hepatic differentiation of these cells relies on exposure to dimethylsulfoxide (DMSO), which, as a side-effect, has a cytotoxic effect and represses an all-round hepatic functionality. The AMCbioartificial liver (AMC-BAL) is a 3D bioreactor that has previously been shown to upregulate various liver functions of cultured cells. We therefore cultured HepaRG cells in the AMC-BAL without DMSO and characterized the drug metabolism. Within 14 days of culture, the HepaRG-AMC-BALs contained highly polarized viable liver-like tissue with heterogeneous expression of cytochrome P450 (CYP) 3A4. We found a substantial metabolism of the tested substrates, ranging from 26% (UDP-glucuronosyltransferase 1A1), 47% (CYP3A4) to 240% (CYP2C9) of primary human hepatocytes. The CYP3A4 activity could be induced 2fold by rifampicin, while CYP2C9 activity remained equally high. The HepaRG-AMC-BAL secreted bile acids at 43% the rate of primary human hepatocytes and demonstrated hydroxylation, conjugation, and transport of bile salts. Concluding, culturing HepaRG cells in the AMC-BAL yields substantial phase 1 and phase 2 drug metabolism, while maintaining high viability, rendering DMSO addition superfluous for the promotion of drug metabolism. Therefore, AMC-BAL culturing makes the HepaRG cells more suitable for testing metabolism and toxicity of drugs. This article has not been copyedited and formatted. The final version may differ from this version. DMD Fast Forward. Published on December 13, 2012 as DOI: 10.1124/dmd.112.049098 at A PE T Jornals on M ay 0, 2017 dm d.aspurnals.org D ow nladed from