title: Krüppel-Like Factor 4 Overexpression Initiates a Mesenchymal-to-Epithelial Transition and Redifferentiation of Human Pancreatic Cells following Expansion in Long Term Adherent Culture.
abstract: A replenishable source of insulin-producing cells has the potential to cure type 1 diabetes. Attempts to culture and expand pancreatic β-cells in vitro have resulted in their transition from insulin-producing epithelial cells to mesenchymal stromal cells (MSCs) with high proliferative capacity but devoid of any hormone production. The aim of this study was to determine whether the transcription factor Krüppel-like factor 4 (KLF4), could induce a mesenchymal-to-epithelial transition (MET) of the cultured cells. Islet-enriched pancreatic cells, allowed to dedifferentiate and expand in adherent cell culture, were transduced with an adenovirus containing KLF4 (Ad-Klf4). Cells were subsequently analysed for changes in cell morphology by light microscopy, and for the presence of epithelial and pancreatic markers by immunocytochemistry and quantitative RT/PCR. Infection with Ad-Klf4 resulted in morphological changes, down-regulation of mesenchymal markers, and re-expression of both epithelial and pancreatic cell markers including insulin and transcription factors specific to β-cells. This effect was further enhanced by culturing cells in suspension. However, the effects of Ad-KLf4 were transient and this was shown to be due to increased apoptosis in Klf4-expressing cells. Klf4 has been recently identified as a pioneer factor with the ability to modulate the structure of chromatin and enhance reprogramming/transdifferentiation. Our results show that Klf4 may have a role in the redifferentiation of expanded pancreatic cells in culture, but before this can be achieved the off-target effects that result in increased apoptosis would need to be overcome.
authors.affiliation: School of Medical Sciences, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom.
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Muir
authors.affiliation: School of Medical Sciences, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom.
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Lima
authors.affiliation: School of Medical Sciences, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom.
authors.forename: Hilary M
authors.initials: HM
authors.lastname: Docherty
authors.affiliation: Department of Surgery, University of Edinburgh, Edinburgh Royal Infirmary, Edinburgh, United Kingdom.
authors.forename: Neil W A
authors.initials: NW
authors.lastname: McGowan
authors.affiliation: Endocrinology Unit, University/BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Shareen
authors.initials: S
authors.lastname: Forbes
authors.affiliation: Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Yves
authors.initials: Y
authors.lastname: Heremans
authors.affiliation: MRC Centre for Regenerative Medicine, SCRM Building, The University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Forbes
authors.affiliation: Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Harry
authors.initials: H
authors.lastname: Heimberg
authors.affiliation: Department of Surgery, University of Edinburgh, Edinburgh Royal Infirmary, Edinburgh, United Kingdom.
authors.forename: John
authors.initials: J
authors.lastname: Casey
authors.affiliation: School of Medical Sciences, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, United Kingdom.
authors.forename: Kevin
authors.initials: K
authors.lastname: Docherty
mesh_terms: D050156:Adipogenesis / Q000235:genetics; D015415:Biomarkers; D002450:Cell Communication / Q000235:genetics; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000235:genetics; D019070:Cell Lineage / Q000235:genetics; D054338:Cell Transdifferentiation / Q000235:genetics*; D002478:Cells, Cultured; D058750:Epithelial-Mesenchymal Transition / Q000235:genetics*; D015870:Gene Expression; D006801:Humans; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000378:metabolism; D007515:Islets of Langerhans / Q000166:cytology / Q000378:metabolism; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors / Q000235:genetics* / Q000378:metabolism; D010012:Osteogenesis / Q000235:genetics; D010179:Pancreas / Q000166:cytology* / Q000378:metabolism*
chemical_list: D015415:Biomarkers; C000715467:KLF4 protein, human; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors