Background: In order to avoid drug-induced liver injury (DILI), in vitro assays, which
enable the assessment of both metabolic activation and immune reaction processes that ultimately
result in DILI, are needed.
Objective: In this study, recent progress in the application of in vitro assays using cell culture systems
is reviewed for potential DILI-causing drugs/xenobiotics and a mechanistic study on DILI, as
well as on the limitations of in vitro cell culture systems for DILI research, was carried out.
Methods: Information related to DILI was collected through a literature search of the PubMed
Results: The initial biological event for the onset of DILI is the formation of cellular protein
adducts after drugs have been metabolically activated by drug metabolizing enzymes. The damaged
peptides derived from protein adducts lead to the activation of CD4+ helper T lymphocytes
and recognition by CD8+ cytotoxic T lymphocytes, which destroy hepatocytes through immunological
reactions. Because DILI is a major cause of drug attrition and drug withdrawal, numerous in
vitro systems consisting of hepatocytes and immune/inflammatory cells or spheroids of human primary
hepatocytes containing non-parenchymal cells have been developed. These cellular-based systems
have identified DILI-inducing drugs, with approximately 50% sensitivity and 90% specificity.
Conclusion: Different co-culture systems consisting of human hepatocyte-derived cells and other
immune/inflammatory cells have enabled the identification of DILI-causing drugs and of the actual
mechanisms of action.