A hollow fiber membrane-based liver organoid-on-a-chip model for examining drug metabolism and transport
Liver-on-a-chip models predictive for both metabolism as well as canalicular and blood transport of drug candidates in humans are lacking. Here, we established an advanced, bioengineered and animal component-free hepatocyte-like millifluidic system based on 3D hollow fiber membranes (HFMs), recombinant human laminin 332 coating and adult human stem cell-derived organoids. Organoid fragments formed polarized and tight monolayers on HFMs with improved hepatocyte-like maturation, as compared to standard 3D organoid cultures in Matrigel from matched donors. Gene expression profiling and immunofluorescence revealed that hepatocyte-like monolayers expressed a broad panel of phase I (e.g., CYP3A4, CYP2D6) and II (UGTs, SULTs) drug-metabolizing enzymes and drug transporters (e.g., OATP1B3, MDR1 and MRP3). Moreover, statically cultured monolayers displayed phase I and II metabolism of a cocktail of six relevant compounds, including midazolam and 7-hydroxycoumarin. We also demonstrated the disposition of midazolam in the basal/blood-like circulation and apical/canalicular-like compartment of the millifluidic chip. Finally, we connected the system to the other two PK/ADME-most relevant organ systems, i.e. small intestine- and kidney proximal tubule-like to study the bioavailability of midazolam and coumarin, and excretion of metformin. In conclusion, we generated a proof-of-concept liver organoid-on-a-chip model for examining metabolism and transport of drugs, which can be further developed to predict PK/ADME profiles in humans.