Comparison of Primary Human Hepatocytes and Hepatoma Cell Line Hepg2 With Regard to Their Biotransformation Properties

Abstract

This article is available online at http://dmd.aspetjournals.org ABSTRACT:Cultures of primary hepatocytes and hepatoma cell line HepG2 are frequently used in in vitro models for human biotransformation studies. In this study, we characterized and compared the capacity of these model systems to indicate the presence of different classes of promutagens. Genotoxic sensitivity, enzyme activity, and gene expression were monitored in response to treatment with food promutagens benzo[a]pyrene, dimethylnitrosamine (DMN), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). DNA damage could be detected reliably with the comet assay in primary human hepatocytes, which were maintained in sandwich culture. All three promutagens caused DNA damage in primary cells, but in HepG2 no genotoxic effects of DMN and PhIP could be detected. We supposed that the lack of specific enzymes accounts for their inability to process these promutagens. Therefore, we quantified the expression of a broad range of genes coding for drug-metabolizing enzymes with real-time reverse transcription-polymerase chain reaction. The genes code for cytochromes P450 and, in addition, for a series of important phase II enzymes. The expression level of these genes in human hepatocytes was similar to those previously reported for human liver samples. On the other hand, expression levels in HepG2 differed significantly from that in human. Activity and expression, especially of phase I enzymes, were demonstrated to be extremely low in HepG2 cells. Up-regulation of specific genes by test substances was similar in both cell types. In conclusion, human hepatocytes are the preferred model for biotransformation in human liver, whereas HepG2 cells may be useful to study regulation of drug-metabolizing enzymes.

Mutagenicity and DNA Damage of Bisphenol a and its Structural Analogues in Hepg2 Cells

“…These cells were selected as they express a range of xenobiotic-metabolising enzymes (36)(37)(38)(39)(40) as well as ERα and ERβ receptors (41). The HepG2 cells were provided by Professor Firouz Darroudi (Leiden University Medical Centre, Department of Toxicogenetics, Leiden, The Netherlands).…”

Assessment of Compound Hepatotoxicity Using Human Plateable Cryopreserved Hepatocytes in a 1536-Well-Plate Format

“…19,20,23 However, HepG2 cells lack the full expression of hepatocyte proteins, such as phase I and phase II metabolizing enzymes and transporters, and thus may not correlate to in vivo hepatotoxicity. [24][25][26] As an alternative to HepG2 cells, primary human hepatocytes represent the best predictive in vitro model to determine liver function for metabolism, 27,28 drug-drug interactions, 29,30 and potential hepatotoxicity of compounds. [30][31][32] Hepatocytes can be utilized in suspension for assays lasting a few hours or may be maintained in collagen-coated tissue culture plates for extended culturing.…”

Present and Future Developments in Hepatic Tissue Engineering for Liver Support Systems

“…drug and ammonia metabolism, in vitro compared with primary counterparts, thereby limiting their application in the support system (Cascio 2001). Furthermore, comparison of primary human hepatocytes and the hepatoma cell line (HepG2) has shown that the former are more suitable for the development of liver support systems with respect to their biotransfomation properties (Wilkening et al 2003). Expansion of autologous hepatocytes in patients with liver disease is not advantageous for at least the following five reasons: (i) The underlying disease, i.e.…”