title: Differentiation of neonatal rat epithelial cells from biliary origin into immature hepatic cells by sequential exposure to hepatogenic cytokines and growth factors reflecting liver development.
abstract: It was investigated whether cryopreserved rat liver epithelial cells (RLEC) from biliary origin are capable of undergoing hepatic differentiation upon sequential exposure to liver-specific factors (fibroblast growth factor (FGF)-4, hepatocyte growth factor (HGF), insulin-transferrin-sodium-selenite (ITS), dexamethasone (Dex) and oncostatin M (OSM)), reflecting liver embryogenesis in vivo. As differentiation progressed, cells acquired a hepatic morphology (polygonal-to-cuboidal shaped, binucleated cells), corresponding well with the phenotypic changes observed. Biliary cytokeratin (CK)19 and connexin (Cx)43-expression both gradually decreased; CK19-expression disappeared even completely. In contrast, hepatic CK18-expression persisted throughout the culture time. Hepatocyte nuclear factor (HNF)3beta, alpha-foetoprotein (AFP), transthyretin (TTR), HNF4, albumin (ALB), HNF1alpha, multidrug resistance protein (MRP)2 and Cx32 were expressed at specific stages during RLEC-differentiation, thereby showing a progressive hepatic maturation. Indeed, immature AFP and mature ALB were sequentially expressed, in line with the in vivo liver embryogenesis. Expression of the early and mid-late 'liver-enriched' transcription factors (LETF) HNF3beta and HNF4 declined and translocated to the cytosol, respectively, while the late LETF HNF1alpha underwent a nuclear upregulation. In conclusion, RLEC are bipotent cells, capable of differentiation into immature hepatocytes in a hepatic-stimulating micro-environment. The robustness of the sequential conditions, developed before for hepatic 'transdifferentiation' of rat bone marrow stem cells (rBMSC), was hereby confirmed.
authors.affiliation: Department of Toxicology, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, B-1090 Brussels, Belgium. Sarah.Snykers@vub.ac.be
authors.forename: Sarah
authors.initials: S
authors.lastname: Snykers
authors.forename: Joery
authors.initials: J
authors.lastname: De Kock
authors.forename: Tamara
authors.initials: T
authors.lastname: Vanhaecke
authors.forename: Vera
authors.initials: V
authors.lastname: Rogiers
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002454:Cell Differentiation / Q000187:drug effects* / Q000502:physiology; D018031:Connexin 43 / Q000235:genetics / Q000378:metabolism; D015925:Cryopreservation; D016207:Cytokines / Q000494:pharmacology*; D003907:Dexamethasone / Q000494:pharmacology; D004847:Epithelial Cells; D051519:Fibroblast Growth Factor 4 / Q000494:pharmacology; D005786:Gene Expression Regulation; D017228:Hepatocyte Growth Factor / Q000494:pharmacology; D022781:Hepatocytes / Q000378:metabolism*; D007328:Insulin / Q000494:pharmacology; D053539:Keratin-19 / Q000235:genetics / Q000378:metabolism; D053683:Oncostatin M / Q000494:pharmacology; D010641:Phenotype; D051381:Rats; D018038:Sodium Selenite / Q000494:pharmacology; D013997:Time Factors; D014168:Transferrin / Q000494:pharmacology
chemical_list: D018031:Connexin 43; D016207:Cytokines; D051519:Fibroblast Growth Factor 4; D007328:Insulin; D053539:Keratin-19; D014168:Transferrin; D053683:Oncostatin M; D017228:Hepatocyte Growth Factor; D003907:Dexamethasone; D018038:Sodium Selenite