Development of a CYP2D6-enhanced HepaRG cell model with improved CYP2D6 metabolic capacity

Area of Science:

• Hepatocyte drug metabolism and toxicity
• Transgenic cell line development
• Pharmacogenomics and drug response variability

Background:

• Drug-induced liver injury necessitates improved in vitro models for toxicity assessment.
• HepaRG cells offer potential but exhibit low Cytochrome P450 2D6 (CYP2D6) expression, limiting their utility.
• CYP2D6 is crucial for inter-individual drug metabolism variability and adverse drug reactions.

Purpose of the Study:

• To enhance CYP2D6 expression in undifferentiated HepaRG cells.
• To generate and characterize transgenic HepaRG cell lines with functional CYP2D6 activity.
• To evaluate the utility of these enhanced cells in drug metabolism and toxicity studies.

Main Methods:

• Development of FLAG-tagged CYP2D6 and IRES-green fluorescent protein (GFP)-co-expressing HepaRG cells.
• Quantification of CYP2D6-mediated bufuralol metabolism.
• Assessment of transgene expression post-differentiation and cytotoxicity of perhexiline.

Main Results:

• Transgenic HepaRG cells showed a 5- to 8,000-fold increase in CYP2D6-mediated bufuralol metabolism.
• CYP2D6 expression levels in a CYP2D6-iGFP cell line were comparable to human liver tissue.
• Enforced CYP2D6 expression tended to reduce perhexiline cytotoxicity; two cell lines retained differentiation potential.

Conclusions:

• CYP2D6-enhanced HepaRG cells provide a valuable in vitro model for studying CYP2D6-mediated drug metabolism.
• These models can improve the prediction of drug toxicity and adverse drug reactions.
• The developed cell lines offer a robust platform for drug development and safety assessment.