Abstract

High Throughput Microscopy Toxicity Pathway Reporters for Drug Safety Assessment

Bob Van de Water, , Leiden University

The activation of adaptive stress response pathways is a key event in drug-induced cell injury. Toxicogenomics has established the key stress pathways that are involved in liver injury. We have established GFP-based adaptive stress response reporters in HepG2 cells based on bacterial artificial chromosome transgenome technology. These reporters allow the analysis of the dynamics of stress pathway activation at the single cell level in high throughput microscopy based assays. Our reporters cover, amongst other, oxidative stress, DNA damage, unfolded protein response and heat shock responses. We have systematically assessed the application of these reporters for the prediction of DILI in both 2D monolayer and 3D spheroid systems using automated imaging and compared our results to data in primary human hepatocytes based on legacy data. In addition, we have applied RNAi screening to unravel the signalling pathways that control the cellular stress responses. Overall the data indicate that different DILI drugs activate different stress response reporters and that these reporters contribute to an improved mechanism-based assessment of DILI liability.