Insulin Production by Human Embryonic Stem Cells

Abstract

Type 1 diabetes generally results from autoimmune destruction of pancreatic islet ␤-cells, with consequent absolute insulin deficiency and complete dependence on exogenous insulin treatment. The relative paucity of donations for pancreas or islet allograft transplantation has prompted the search for alternative sources for ␤-cell replacement therapy. In the current study, we used pluripotent undifferentiated human embryonic stem (hES) cells as a model system for lineage-specific differentiation. Using hES cells in both adherent and suspension culture conditions, we observed spontaneous in vitro differentiation that included the generation of cells with characteristics of insulin-producing ␤-cells. Immunohistochemical staining for insulin was observed in a surprisingly high percentage of cells. Secretion of insulin into the medium was observed in a differentiation-dependent manner and was associated with the appearance of other ␤-cell markers. These findings validate the hES cell model system as a potential basis for enrichment of human ␤-cells or their precursors, as a possible future source for cell replacement therapy in diabetes.

Directed differentiation of human embryonic stem cells towards a pancreatic cell fate

“…It was previously reported that insulin-producing cells were found in EBs after spontaneous in vitro differentiation of hESCs [5]. A more recent study using the spontaneous differentiation strategy without EB formation showed that differentiated hESCs containing PDX1 + progenitors were able to differentiate into cells expressing islet cell markers when co-transplanted with mouse fetal dorsal pancreas [7].…”

“…To date, only a few studies have suggested the potential of hESCs to differentiate into insulin-producing cells [5][6][7][8]. It was previously reported that insulin-producing cells were found in EBs after spontaneous in vitro differentiation of hESCs [5].…”

“…Based on these findings, recent studies have also suggested the potential of hESCs to differentiate into insulin-producing cells through spontaneous in vitro differentiation [5] or the use of a multi-stage protocol [6]. However, several studies have claimed that insulin staining of ESC-derived cells is likely due to insulin uptake by apoptotic cells from the culture medium [19][20][21], suggesting that more reliable analyses should be considered in terms of beta cell physiology and from an embryological standpoint.…”

“…To date, while many studies have reported that hESCs could be efficiently induced to differentiate into mesodermal and ectodermal lineages, such as cardiomyocytes [1], endothelial cells [2], blood cells [3] and nerve cells [4], few reports have focused on the conversion of hESCs into endodermal lineages, particularly into pancreatic cell types [5][6][7][8], which may provide a limitless stock of insulin-producing cells to treat type 1 diabetes. Moreover, despite increasing knowledge on pancreatic development, there is still debate regarding the origin of beta cells and the markers that can be used to identify their progenitors [9].…”

Adult Stem Cell Plasticity: Dream or Reality?

“…He announced that only ESC lines that had already been established and are now catalogued in the National Institute of Health Embryonic stem cell registry, would be able to be used for federally sponsored research [7]. Use of the established cell lines has demonstrated that ESCs have the potential to regenerate differentiated cells, with applicability to neurological degenerative disorders, [10] diabetes mellitus [11] and heart diseases [12]. The Ethics committee of the American Society for Human Reproductive Medicine has proposed that a consent form be devised that would enable "spare" embryos developed by couples undergoing in vitro fertilization to be donated for research.…”