Untitled

Abstract

Objectives: In diabetes mellitus type 1, beta cells are mostly destroyed; while in diabetes mellitus type 2, beta cells are reduced by 40% to 60%. We hope that soon, stem cells can be used in diabetes therapy via pancreatic beta cell replacement. Induced pluripotent stem cells are a kind of stem cell taken from an adult somatic cell by "stimulating" certain genes. These induced pluripotent stem cells may be a promising source of cell therapy. This study sought to produce isletlike clusters of insulin-producing cells taken from induced pluripotent stem cells. Materials and Methods: A human-induced pluripotent stem cell line was induced into isletlike clusters via a 4-step protocol, by adding insulin, transferrin, and selenium (ITS), N2, B27, fibroblast growth factor, and nicotinamide. During differentiation, expression of pancreatic β-cell genes was evaluated by reverse transcriptase-polymerase chain reaction; the morphologic changes of induced pluripotent stem cells toward isletlike clusters were observed by a light microscope. Dithizone staining was used to stain these isletlike clusters. Insulin produced by these clusters was evaluated by radio immunosorbent assay, and the secretion capacity was analyzed with a glucose challenge test. Results: Differentiation was evaluated by analyzing the morphology, dithizone staining, real-time quantitative polymerase chain reaction, and immunocytochemistry. Gene expression of insulin, glucagon, PDX1, NGN3, PAX4, PAX6, NKX6.1, KIR6.2, and GLUT2 were documented by analyzing real-time quantitative polymerase chain reaction. Dithizonestained cellular clusters were observed after 23 days. The isletlike clusters significantly produced insulin. The isletlike clusters could increase insulin secretion after a glucose challenge test. Conclusions:This work provides a model for studying the differentiation of human-induced pluripotent stem cells to insulin-producing cells.

Pancreatic β Cell Mass Death

“…For this discovery, a deserving Shinya Yamanaka shared the Nobel Prize in Physiology or Medicine in 2012. Since the Yamanaka protocol was published, several studies have demonstrated the possibility of manipulating adult cells into insulin-producing cells (Thatava et al, 2013 ; Shaer et al, 2015 ). The protocol to produce rich β cell cultures is still being refined and is not without hurdles.…”

Inducing pluripotency in vitro: recent advances and highlights in induced pluripotent stem cells generation and pluripotency reprogramming

“…Human induced pluripotent stem cells hold great promise for tailored cell-based therapies. Functional hiPSC derivatives such as astrocytes, dopaminergic neurons, retinal pigment epithelium cells, adipocyte progenitors, insulin-producing islet-like clusters, bone substitutes, hepatocytes, melanocytes, erythroblasts, cardiomyocytes and red blood cells have already been generated (127)(128)(129)(130)(131)(132)(133)(134)(135)(136)(137). Considering damaged tissues account for many chronic illnesses, such as neurodegenerative diseases, retinal degeneration, muscular dystrophy and myocardial infarction, patient-specific hiPSC derivatives can be a suitable therapeutic choice.…”

Retinoic acid induced expression of Hnf1β and Fzd4 is required for pancreas development in Xenopus laevis

“…The Xenopus explant system has been used to generate pancreatic tissue by the utilisation of simple protocols, including an endoderm-inducing factor and RA ( Moriya et al, 2000b ; Chen et al, 2004 ). Protocols for the generation of pancreatic tissue from hESCs or iPSCs similarly include RA, even though such multistep protocols are more complex and include multiple signalling molecules ( Pagliuca et al, 2014 ; Shaer et al, 2015 ).…”

“…This same protocol, which was also utilised in the current study, aims to mimic early key regulatory events, given that RA signalling together with inhibition of BMP activity makes it possible to convert ventral endomesodermal explants from gastrula-stage Xenopus embryos to a pancreatic fate ( Pan et al, 2007 ). Similarly, experimental protocols for the in vitro generation of β cells from embryonic stem cells (ESCs) ( Kroon et al, 2008 ; Rezania et al, 2012 ; Schulz et al, 2012 ; Pagliuca et al, 2014 ) or induced pluripotent stem cells (iPSCs) ( Zhang et al, 2009 ; Schiesser et al, 2014 ; Shaer et al, 2015 ) all include application of RA.…”