Conversion of immortal liver progenitor cells into pancreatic endocrine progenitor cells by persistent expression of Pdx‐1

Abstract

The conversion of expandable liver progenitor cells into pancreatic beta cells would provide a renewable cell source for diabetes cell therapy. Previously, we reported the establishment of liver epithelial progenitor cells (LEPCs). In this work, LEPCs were modified into EGFP/Pdx-1 LEPCs, cells with stable expression of both Pdx-1 and EGFP. Unlike previous work, with persistent expression of Pdx-1, EGFP/Pdx-1 LEPCs acquired the phenotype of pancreatic endocrine progenitor cells rather than giving rise to insulin-producing cells directly. EGFP/Pdx-1 LEPCs proliferated vigorously and expressed the crucial transcription factors involved in beta cell development, including Ngn3, NeuroD, Nkx2.2, Nkx6.1, Pax4, Pax6, Isl1, MafA and endogenous Pdx-1, but did not secrete insulin. When cultured in high glucose/low serum medium supplemented with cytokines, EGFP/Pdx-1 LEPCs stopped proliferating and gave rise to functional beta cells without any evidence of exocrine or other islet cell lineage differentiation. When transplanted into diabetic SCID mice, EGFP/Pdx-1 LEPCs ameliorated hyperglycemia by secreting insulin in a glucose regulated manner. Considering the limited availability of beta cells, we propose that our experiments will provide a framework for utilizing the immortal liver progenitor cells as a renewable cell source for the generation of functional pancreatic beta cells.

PDX1 Binds and Represses Hepatic Genes to Ensure Robust Pancreatic Commitment in Differentiating Human Embryonic Stem Cells

“…PDX1 overexpression experiments provide some evidence that this factor can partially engage the pancreatic program while conversely suppressing endogenous liver genes. In studies with primary rodent hepatocytes or liver epithelial cells, Alb levels were variably downregulated by overexpressing PDX1 or PDX1-VP16 ( Fodor et al., 2007; Jin et al., 2008; Meivar-Levy et al., 2007; Yamada et al., 2006 ). Li et al.…”

CELLPEDIA: a repository for human cell information for cell studies and differentiation analyses

“…It is noteworthy that distant relationships between cells can be deduced by following consecutive neighborhood links. For example, the differentiation route of liver progenitor cells to pancreatic beta cells, which is already reported (34), is determined by successively following the links from ‘liver progenitor cell (stem cell ID:802, Figure 4a top) to hepatocyte (differentiated cell ID:160032, Figure 4a bottom)’ and from ‘hepatocyte to pancreatic beta cell (differentiated cell ID:150041, Figure 4a right)’.…”

Generation of Functional Insulin-Producing Cells from Neonatal Porcine Liver-Derived Cells by PDX1/VP16, BETA2/NeuroD and MafA

“…Ferber’s group reported that in vivo transduction of Ad-PDX1 into the mouse liver results in the production of substantial amounts of insulin [31] . Extensive research has been undertaken to investigate the in vitro transdifferentiation of adult liver cells from rodents [3] , [23] , [24] , [32] , [33] and humans [25] , [34] using virus-mediated gene delivery systems as a potential source of β-cells for transplantation into patients with type 1 diabetes. Although these cells transdifferentiate to express insulin, they are clearly far from true pancreatic β-cells, and major obstacles remain to be overcome.…”