title: Characterization of endocrine progenitor cells and critical factors for their differentiation in human adult pancreatic cell culture.
abstract: We have reproduced a previously described method for the in vitro generation of endocrine cells in adult human pancreatic tissue culture. The aim of this study was to characterize the nature of pancreatic progenitor cells and to identify the factors necessary for their differentiation in this model. During monolayer expansion, two types of cells proliferated sequentially; first cytokeratin 19 (CK19)-positive ductal epithelial cells and then nestin-positive fibroblastoid cells. After the bromodeoxyuridine-labeled cells were traced in differentiated islet buds, some of the proliferating ductal cells had differentiated into endocrine cells, whereas nestin-positive cells could not give rise to endocrine tissue. Serum-free culture was found to be an absolute requirement for the endocrine differentiation to occur. Also, overlay of the cells with Matrigel was essential, whereas nicotinamide had a potentiating effect. The in vitro-generated islet buds released insulin in response to glucose nearly as efficiently as native islets. When transplanted under the kidney capsule of nude mice, only one of five grafts demonstrated further growth with foci of both endocrine and exocrine differentiation. Our results support the previous notion that pancreatic progenitor cells represent a subpopulation of ductal epithelial cells. No evidence was found for the development of endocrine cells from nestin-positive stem cells.
authors.affiliation: Program of Developmental and Reproductive Biology, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland.
authors.forename: Ru
authors.initials: R
authors.lastname: Gao
authors.forename: Jarkko
authors.initials: J
authors.lastname: Ustinov
authors.forename: Mari-Anne
authors.initials: MA
authors.lastname: Pulkkinen
authors.forename: Karolina
authors.initials: K
authors.lastname: Lundin
authors.forename: Olle
authors.initials: O
authors.lastname: Korsgren
authors.forename: Timo
authors.initials: T
authors.lastname: Otonkoski
mesh_terms: D000328:Adult; D000818:Animals; D001672:Biocompatible Materials; D002454:Cell Differentiation / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D003094:Collagen; D004338:Drug Combinations; D004847:Epithelial Cells / Q000737:chemistry / Q000166:cytology; D015870:Gene Expression / Q000502:physiology; D005934:Glucagon / Q000235:genetics; D006801:Humans; D007328:Insulin / Q000235:genetics / Q000378:metabolism; D007381:Intermediate Filament Proteins / Q000032:analysis; D007515:Islets of Langerhans / Q000737:chemistry / Q000166:cytology* / Q000378:metabolism; D016381:Islets of Langerhans Transplantation; D007633:Keratins / Q000032:analysis; D007797:Laminin; D051379:Mice; D008819:Mice, Nude; D009419:Nerve Tissue Proteins; D064231:Nestin; D011509:Proteoglycans; D013234:Stem Cells / Q000737:chemistry / Q000166:cytology*
chemical_list: D001672:Biocompatible Materials; D004338:Drug Combinations; D007328:Insulin; D007381:Intermediate Filament Proteins; D007797:Laminin; C577484:NES protein, human; D009419:Nerve Tissue Proteins; C577485:Nes protein, mouse; D064231:Nestin; D011509:Proteoglycans; C059485:matrigel; D007633:Keratins; D003094:Collagen; D005934:Glucagon