PDX1- /NKX6.1+ progenitors derived from human pluripotent stem cells as a novel source of insulin-secreting cells.

Abstract

Beta cell replacement strategies are a promising alternative for diabetes treatment. Human pluripotent stem cells (hPSCs) serve as a scalable source for producing insulin-secreting cells for transplantation therapy. We recently generated novel hPSC-derived pancreatic progenitors, expressing high levels of the transcription factor NKX6.1, in the absence of PDX1 (PDX1- /NKX6.1+ ). Herein, our aim was to characterize this novel population and assess its ability to differentiate into insulin-secreting beta cells in vitro. Three different hPSC lines were differentiated into PDX1- /NKX6.1+ progenitors, which were further differentiated into insulin-secreting cells using two different protocols. The progenitors and beta cells were extensively characterized. Transcriptome analysis was performed at different stages and compared with the profiles of various pancreatic counterparts. PDX1- /NKX6.1+ progenitors expressed high levels of nestin, a key marker of pancreatic islet-derived progenitors, in the absence of E-cadherin, similar to pancreatic mesenchymal stem cells. At progenitor stage, comparison of the two populations showed downregulation of pancreatic epithelial genes and upregulation of neuronal development genes in PDX1- /NKX6.1+ cells in comparison to the PDX1+ /NKX6.1+ cells. Interestingly, on further differentiation, PDX1- /NKX6.1+ cells generated mono-hormonal insulin+ cells and activated pancreatic key genes, such as PDX1. The transcriptome profile of PDX1- /NKX6.1+ -derived beta (3D-beta) was closely similar to those of human pancreatic islets and purified hPSC-derived beta cells. Also, the 3D-beta cells secreted C-peptide in response to increased glucose concentrations indicating their functionality. These findings provide a novel source of insulin-secreting cells that can be used for beta cell therapy for diabetes.