In-vitro ADME applications
Drug metabolism and clearance
HepaRG™ cells be classified as an “average human hepatocyte population” and express multiple functional Phase 1 and 2 drug metabolising enzyme (DME) activities comparable to levels in cultures of primary human hepatocytes. This makes them a much better model for metabolism and clearance studies than any other cell line currently available. The prediction of in-vivo intrinsic clearance of a panel of drugs has been shown to be mostly within 2‑fold using HepaRG™ cells. Moreover, the sustained presence of DMEs over weeks makes them ideal for measuring the clearance of low clearance compounds.
HepaRG™ cells have a full complement of DMEs, cofactors and transporter proteins and the profile of DME activities and expression provides a good representation of that in primary human hepatocytes. Together with the high stability of the enzymes, this makes these cells ideal for producing relevant drug metabolites in sufficient quantities to enable metabolite identification.
DME induction assays
HepaRG™ cells express functional transcription factors involved in the regulation of DMEs. These cells are responsive to prototypical inducers of CYP1A1/2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, and CYP3A4 and can be used to predict in-vivo CYP3A4 induction of test compounds by constructing a calibration curve using known potent and mild inducers of this CYP (“AUC/F2” or “RIS”). The protocol for CYP induction using HepaRG™ cells has been accepted by ESAC and an OECD guideline for use of HepaRG™ cells in induction studies is in preparation.
DME inhibition assays
The high levels of DMEs in HepaRG™ cells makes them ideal for inhibition screening studies. The IC50 values of a panel of CYP inhibitors using HepaRG™ cells correlated very well with those determined in primary human hepatocytes. Time-dependent inhibition can also be investigated using these cells.
Functional transporter assays
HepaRG™ cells express a number of uptake and efflux drug transporters and form tight junctions and bile canaliculi, making them ideal for uptake and biliary secretion studies.
Hepatotoxicity screening and mechanistic testing applications
Carbohydrate and lipid metabolism
HepaRG™ cells display glucose and insulin responsiveness and can be used to investigate carbohydrate homeostasis and lipogenesis.
The stable and high levels of DMEs in HepaRG™ cells make them ideal for long-term and repeated dose toxicity studies in which a compound may be bioactivated and/or cause latent effects over days or weeks.
The accumulation triglycerides in HepaRG™ cells is predictive of the in-vivo steatosis reported in patients chronically treated with steatogenic drugs. Lipid accumulation directly correlates with levels of mRNA encoding for lipid synthesis markers, thus this toxicity can be monitored visually and at the gene level.
HepaRG™ cells can be used to discriminate between drugs which cause steatosis (after 24 h) and phospholipidosis (evident after 2 weeks) e.g. amiodarone; and those which cause steatosis only e.g. tetracycline.
Cholestatic drugs (via direct inhibition or down-regulation) can be identified by measuring their effects on bile acid efflux in HepaRG™ cells.
Genotoxicity and carcinogenicity
Since HepaRG™ cells have a good metabolic capacity and proliferative capacity, they can be implemented into the micronucleus test (MNT), as recommended by ECVAM and IWGT workshops. Whole genome expression analysis of HepaRG™ cells can discriminate between genotoxic and non-genotoxic compounds and provide information on compound- and time-dependent effects on cell cycle and apoptosis signalling pathways.
BioArtificial Livers (BALs)
HepaRG™ cells can be cultured in 3D bioreactors to generate an in-vivo-like assembly of highly polarised cells with high and sustained CYP activities. This makes them a promising cell type for use as liver assist devices or BALs.
Transgenic liver humanized animals with HepaRG™ cells
HepaRG™ cells can be transplanted into chimeric mice to repopulate their livers and express human primary hepatocyte–specific genes and proteins. Such a HepaRG™-mouse combination represents a promising model for in-vivo studies of drug metabolism and hepatitis virus infections.
Dynamic fluidic models
Stem cell cultures
HBV, HCV, HEV
HepaRG™ cells support viral replication can be used to model viral infection and provide insight into the processes involved in virus receptor binding, uptake, and membrane fusion.