In the future, iMPCCs could provide a more mature and long-term culture platform for studying molecular mechanisms underlying iHLC differentiation, modeling liver diseases, and integration into organs-on-a-chip

systems being designed to assess INCB018424 molecular weight multi-tissue responses to compounds and other perturbations. Disclosures: Salman Khetani – Stock Shareholder: Hepregen Corporation The following people have nothing to disclose: Dustin Berger, Brenton R. Ware, Matthew Davidson To date, there are no reliable in vitro models of humn liver tissue development. It was previously shown the human fetal liver progenitor cells (hFLPCs) are bipotent and give rise to the two major liver cell types, hepatocytes and cholangiocytes, and thus can be used to create a functional liver tissue. The goal of our study was to develop a 3D organoid system that would efficiently recapitulate the fetal liver development process. The use LDE225 concentration of decellularized liver extracellular matrix (LECM) as scaffolds and hFLPCs as cell source offers an ideal system for this purpose. LECM discs (300 μm thickness, 8 mm diameter) were prepared from these scaffolds and seeded with upto 0.5 × 106 hFLPCs. The cells were cultured for 3 weeks in hepatic differentiation

medium. Immunofluorescence microscopy and RT-PCR analysis were used to determine the extent of progenitor cell differentiation into hepatocytes and cholangiocytes within these scaffolds. Urea, albumin and drug metabolism were quantified as parameters of liver function. LECM discs seeded with BCKDHA hFLPs self-assembled into 3D organoid in culture and the cells differentiated into hepatocytes and cholangiocytes. Immunostaining analysis showed clusters of cells expressing hepatocytic markers like albumin, HNF-4α, α-1 antitrypsin and

CYP3A4. These results were further confirmed with gene expression analysis for hepatocyte specific markers such as transferrin, glucose-6-phos-phatase, tyrosine transaminase. Urea and albumin secretion was higher in liver organoids compared to hFLPs in 2D culture. These organoids also metabolized diazepam and 7-ethoxycou-marin and expressed various isoforms of CYP450. The liver organoids presented 4 different stages of bile duct formations, similar to the duct developmental stages observed in human fetal liver. The cells in these ductular structures expressed bile duct specific markers like CK19, SOX9, EpCAM, ASBT and p-catenin, a-acetylated tubulin, thus demonstrating differentiation towards cholangiocyte lineage. Our results demonstrate the efficient generation of self-assembled human liver organoid that recapitulates stepwise development of hepatocyte and bile duct formation. Altogether, this study demonstrates the potential of this technology to study and mimic human liver development. These models provide novel approaches for liver bioengineering, drug discovery and toxicology, and ultimately for the treatment of liver disease.