Development of a novel 96-well bioreactor platform for the combined assessment of drug efficacy and toxicity in human liver and kidney

Abstract

Background and Aims Bringing a new drug to market can cost as much as $2.8 billion, with significant attrition rates in later phase trials. As many as 20-40% of these exclusions are due to unforeseen toxicity. Current predictive 2D cell culture and in vivo animal models have limitations, therefore human tissue pre-clinical modelling platforms for efficacy and toxicity testing of novel compounds, may provide a solution. This project aimed to develop a novel 96- well bioreactor to culture precision cut tissue slices (PCTS) to assess the efficacy and potential toxicities of novel therapeutics. As major sites of xenobiotic metabolism and excretion, PCTS generated from human liver and kidney tissue were selected for this. Methods 3mm PCTS generated from 250μm thick tissue sheets were cultured for up to 96h with daily media changes. Viability, health and disease biomarkers were assessed using resazurin assays, ELISAs, histology/immunohistochemistry and MSD panels. Results In 96-well plate cultured human liver and kidney slices, fibrogenesis was induced upon challenge with fibrotic stimuli TGFβ1/PDGFββ, and acute inflammation was promoted using LPS, IL-1α and IL-1β. Challenge with TGFβ1/PDGFββ increased collagen deposition, measured by PSR and soluble collagen 1a1 ELISA, and increased myofibroblast activation, measured by αSMA staining. Challenge with inflammatory stimuli upregulated production of pro-inflammatory cytokines such as IL-6, IL-8 and TNFα. Modelling of fibrogenesis and inflammation was reproducible across multiple donors and could be dose dependently supressed using Alk5 or IKK2 inhibitors respectively. Next, the predictive value of the bioreactor in toxicity modelling was assessed using clinically approved drugs known to be hepatotoxic or nephrotoxic. Different treatment regimens were used to identify the best way to predict adverse outcomes in bioreactor cultured PCTS. Conclusion The novel 96-well bioreactor platform can be used for target validation of anti-fibrotic and anti-inflammatory compounds and to assess toxicity. Ex vivo bioreactor cultured PCTS are a helpful tool to test novel therapeutics and can reduce reliance on less physiologically relevant 2D models.