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, and blood and canalicular transport of drug candidates in humans are lacking. Here, we established a bioengineered and 3Rs-complied (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, CYP2C9) and II (e.g. UGTs, SULTs) drug-metabolizing enzymes and drug transporters (e.g. MDR1, MRP3, OATP1B3). 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 studied the bioavailability of midazolam and coumarin on-a-chip in combination with a small intestine-like system. 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 pharmacokinetics' (PK)/absorption, distribution, metabolism and excretion (ADME) profiles in humans.