TABLE 1

Examples of in vitro human liver cell models proposed for use in iDILI prediction

Cell ModelCharacteristicsAdvantagesDisadvantagesReferences
HepG2 cellsHuman liver-derived cell lineSimple modelLow drug-metabolizing enzyme expressionGodoy et al. (2013), Atienzar et al. (2014, 2016)
Suitable for short-term and longer-term studiesPoor expression of plasma membrane transporters
Multiple endpoints can be evaluated
Suitable for high-volume and multiparametric data generation
HepaRG cellsHuman hepatoma-derived cell lineCan be differentiated into hepatocyte-like and biliary epithelial-like cellsLimited commercial availabilityGuillouzo et al. (2007), Ott et al. (2017)
Better maintenance of “hepatocyte-like” drug-metabolizing enzymes and membrane transporters than HepG2 cellsComplex cell culture conditions are needed
Multiple endpoints can be evaluatedCells exhibit limited metabolizing enzyme phenotype
P450 activities are lower than those in isolated primary hepatocytes
Cell lines expressing human P450sHuman liver-derived cell lines transfected with individual human P450sStably transfected cell lines are a simple model, well suited to multiparametric data generation plus acute and long-term toxicity studiesTransfected cell lines do not express hepatocyte-like cell phenotype, or many membrane transporters expressionDambach et al. (2005), Hosomi et al. (2011), Tolosa et al. (2013), Gustafsson et al. (2014)
Enable direct comparison between cell toxicity caused by parent compound (to mock-transfected cells) and metabolites (to transfected cells)Unbalanced metabolism, since only selected P450s are expressed
Isolated hepatocytesIsolated human hepatocytesFreshly isolated hepatocytes express “in vivo–like” high drug metabolism activityLimited availability of human donor liversHewitt et al. (2007), Xu et al. (2008); Usui et al. (2009), Ansede et al. (2010), Nakamura et al. (2010), Wolf et al. (2010), Thompson et al. (2012), Barber et al. (2015)
Good maintenance of viability, for multiple days, when cultured as monolayersHuman liver exhibits marked interindividual variability
When cultured appropriately (ideally in sandwich configuration), regain polarized plasma membrane transporter expression and are well suited to multiparametric data generationFreshly isolated hepatocytes in suspension are viable only for several hours and do not exhibit polarized plasma membrane transporter expression
Longer-term hepatocyte culture is technically challenging and these cells fail to maintain high P450 expression
Interindividual donor variability may influence results
Micropatterned hepatocyte/accessory cell coculturesIsolated hepatocytes cocultured with macrophages or other accessory cellsGood maintenance of viability, drug-metabolizing enzymatic activity, and membrane transporters, for multiple daysTechnically challenging to prepare; commercial supply is requiredUnderhill and Khetani (2017)
Numerous endpoints can be evaluated, at a single cell levelLimited variety and physiologic relevance of accessory cells
Limited toxicity characterization
Interindividual donor variability may influence results
Liver microtissues (spheroids)Liver cell aggregates, which includes hepatocytes and multiple nonparenchymal cell typesGood maintenance of viability, drug-metabolizing enzyme activity, and membrane transporters, for multiple daysTechnically challenging to prepare; commercial supply is requiredBell et al. (2016), Proctor et al. (2017)
Limited toxicity characterization
Endpoints cannot be quantified at a single cell level
Interindividual donor variability may influence results
Microfluidic devicesHepatocytes, multiple liver cell types, or liver-derived cell line devices that reproduce in vivo oxygen tension gradients and/or fluid flowImproved maintenance of viability and drug-metabolizing enzyme activity, and membrane transporters, for multiple days, compared with nonmicrofluidic cell modelsTechnically challenging to prepare; commercial supply of devices is requiredVernetti et al. (2016)
Limited toxicity characterization
Interindividual donor variability may influence results
Stem cell–derived hepatocytesHepatocytes or other differentiated human liver cells, generated via stem cell technologyIf successful, could provide cells in large amounts that replace a need for cell isolation from human donor liversComplex cell differentiation protocols are requiredGoldring et al. (2017)
Currently available conditions provide poorly differentiated cells
Limited toxicity characterization