title: Suppression of epithelial-to-mesenchymal transitioning enhances ex vivo reprogramming of human exocrine pancreatic tissue toward functional insulin-producing β-like cells.
abstract: Because of the lack of tissue available for islet transplantation, new sources of β-cells have been sought for the treatment of type 1 diabetes. The aim of this study was to determine whether the human exocrine-enriched fraction from the islet isolation procedure could be reprogrammed to provide additional islet tissue for transplantation. The exocrine-enriched cells rapidly dedifferentiated in culture and grew as a mesenchymal monolayer. Genetic lineage tracing confirmed that these mesenchymal cells arose, in part, through a process of epithelial-to-mesenchymal transitioning (EMT). A protocol was developed whereby transduction of these mesenchymal cells with adenoviruses containing Pdx1, Ngn3, MafA, and Pax4 generated a population of cells that were enriched in glucagon-secreting α-like cells. Transdifferentiation or reprogramming toward insulin-secreting β-cells was enhanced, however, when using unpassaged cells in combination with inhibition of EMT by inclusion of Rho-associated kinase (ROCK) and transforming growth factor-β1 inhibitors. Resultant cells were able to secrete insulin in response to glucose and on transplantation were able to normalize blood glucose levels in streptozotocin diabetic NOD/SCID mice. In conclusion, reprogramming of human exocrine-enriched tissue can be best achieved using fresh material under conditions whereby EMT is inhibited, rather than allowing the culture to expand as a mesenchymal monolayer.
authors.affiliation: School of Medical Sciences, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, UK.
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Lima
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Muir
authors.forename: Hilary M
authors.initials: HM
authors.lastname: Docherty
authors.forename: Robert
authors.initials: R
authors.lastname: Drummond
authors.forename: Neil W A
authors.initials: NW
authors.lastname: McGowan
authors.forename: Shareen
authors.initials: S
authors.lastname: Forbes
authors.forename: Yves
authors.initials: Y
authors.lastname: Heremans
authors.forename: Isabelle
authors.initials: I
authors.lastname: Houbracken
authors.forename: James A
authors.initials: JA
authors.lastname: Ross
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Forbes
authors.forename: Philippe
authors.initials: P
authors.lastname: Ravassard
authors.forename: Harry
authors.initials: H
authors.lastname: Heimberg
authors.forename: John
authors.initials: J
authors.lastname: Casey
authors.forename: Kevin
authors.initials: K
authors.lastname: Docherty
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology*; D002478:Cells, Cultured; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism; D058750:Epithelial-Mesenchymal Transition / Q000502:physiology*; D005947:Glucose / Q000494:pharmacology; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D046790:Pancreas, Exocrine / Q000187:drug effects / Q000378:metabolism*; D054460:rho-Associated Kinases / Q000378:metabolism
chemical_list: D007328:Insulin; D054460:rho-Associated Kinases; D005947:Glucose