title: In vitro formation of β cell pseudoislets using islet-derived endothelial cells.
abstract: β cell pseudoislets (PIs) are used for the in vitro study of β-cells in a three-dimensional (3-D) configuration. Current methods of PI induction require unique culture conditions and extensive mechanical manipulations. Here we report a novel co-culture system consisting of high passage β-cells and islet-derived endothelial cells (iECs) that results in a rapid and spontaneous formation of free-floating PIs. PI structures were formed as early as 72 h following co-culture setup and were preserved for more than 14 d. These PIs, composed solely of β-cells, were similar in size to that of native islets and showed an increased percentage of proinsulin-positive cells, increased insulin gene expression in response to glucose stimulation, and restored glucose-stimulated insulin secretion when compared to β-cells cultured as monolayers. Key extracellular matrix proteins that were absent in β-cells cultured alone were deposited by iECs on PIs and were found in and around the PIs. iEC-induced PIs are a readily available tool for examining β cell function in a native 3-D configuration and can be used for examining β-cell/iEC interactions in vitro.
authors.affiliation: Research Institute, Islet Biology, Winthrop-University Hospital, Mineola, New York, United States of America.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Spelios
authors.forename: Lauren A
authors.initials: LA
authors.lastname: Kenna
authors.forename: Bonnie
authors.initials: B
authors.lastname: Wall
authors.forename: Eitan M
authors.initials: EM
authors.lastname: Akirav
mesh_terms: D000818:Animals; D018929:Cell Culture Techniques; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D024141:Collagen Type IV / Q000378:metabolism; D042783:Endothelial Cells / Q000502:physiology*; D050417:Insulin-Secreting Cells / Q000502:physiology*; D007515:Islets of Langerhans / Q000166:cytology; D007797:Laminin / Q000378:metabolism; D051379:Mice
chemical_list: D024141:Collagen Type IV; D007797:Laminin