FEBS open bio 2014;4:43–54. FD GRATTE,1 JK OLYNYK,1,2,3 GCT YEOH,4 D TOSH,5 DR COOMBE,1 JEE TIRNITZ-PARKER1,2 1School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Perth, Australia, 2School of Medicine and Pharmacology, University of Western Australia, Fremantle, Australia, 3Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia, 4Harry Perkins Institute of Medical Research, Perth, Australia, 5Centre for Regenerative Medicine,

University of Bath, Bath, UK Background: Rising incidences of chronic liver disease and organ shortage for orthotopic liver transplantation have prompted interest into the development of alternative sources of liver tissue. Previous studies have highlighted the potential of cell-based technologies for the in vitro production of hepatocytes for transplantation, including the use of pancreatic Akt inhibitor progenitor cells (PPCs).1 Pancreatic progenitor cells are able to generate hepatocyte-like cells via pancreas-to-liver transdifferentiation after stimulation with the glucocorticoid dexamethasone in conjunction with other liver-promoting growth factors and cell culture supplements. Traditional methods utilize fetal bovine serum, an

undefined concoction of growth factors and extracellular matrix (ECM) HTS assay components, which is unsuitable for use in 上海皓元医药股份有限公司 human treatments. Therefore the development of novel methods using defined levels of growth factors and ECM proteins in a serum-free environment is necessary for future cell-based therapies. Methods: The clonal pancreatic cell line AR42J-B13 was cultured in basal medium (control group) or under differentiation-inducing conditions, on fibronectin or laminin, with and without serum, for five days. Cells were continuously assessed for morphological changes and subjected to transcriptome or immunofluorescent

analyses on days 3 and 5 of the transdifferentiation protocol. Changes in pancreatic (amylase) and hepatocytic (hepatocyte nuclear factor 4α, albumin, tyrosine aminotransferase and transthyretin) gene and/or protein expression were evaluated. To test for hepatocyte functionality, periodic acid-Schiff staining for glycogen storage and indocyanine green uptake and release assays were performed. Results: Undifferentiated AR42J-B13 cells grew in grape-like collections of small, amylase-expressing cells and displayed little or no expression of hepatocytic markers. All groups subjected to differentiation-inducing conditions quickly formed monolayer cultures, showed rapid morphological changes including significant enlargement of all cells and bi- or multinucleation (hallmark of hepatocytes) in a subpopulation of cells. Correspondingly, cells changed their gene and protein expression pattern from a pancreatic to a hepatocytic phenotype.