The Differentiation From Mouse Embryonic Stem Cells To Insulin-producing Cells

Recent years, the public is paying attention to diabetes mellitus. The number of diabetics, even the youngers, is rising. β-cell replacement therapy through islet transplantation has renewed interest, due to the recent improved success of this procedure. However, this successful new protocol, the Edmonton protocol, uses the islets isolated from at least two human cadaveric pancreases. In order to make such a therapy available to more than a few of the thousands of patients with diabetes, new sources of insulin-producing cells must be identified, such as islet cells derived from stem cells.Embryonic stem cells (ESC) are pluripotent cells derived from the inner cell mass (ICM) of pre-implantation mouse embryos or primordial germ cells (PGC) of embryos, and are capable of both self-renewal and multilineage differentiation. Since the establishment of embryonic stem cells lines, ESC has already been a useful tool for studying cell differentiation, the mechanism of development, gene function, medicine selection, cell therapy and so on. Based on the establishment of embryonic stem cells lines, scientists can do their upper research work for differentiation from ESC. Our aims are differentiation from ESC to insulin-producing cells.Firstly, mouse islets cells were isolated and purified, then were stained by dithizone (DTZ). DTZ, a zinc-chelating agent, is known to selectively stain pancreatic 6 cells crimson red, as they contain a large amount of zinc. Using this characteristic of DTZ, we identified insulin-producing cells in our experiments.Secondly, primary murine embryonic fibroblasts were established and mouse embryonic stem cell was cultured and passaged. As the feeder - cell of ES cells, MEF should be used and treated by mitomycin C for 2 hours before the 4th passage.Thirdly, the main part of my paper is the differentiation from mouse embryonic stem cell to insulin-priducing cells. ES cells were suspended in low glucose DMEM in the absence of LIF, supplying insulin, in order to form EBs. After being transfered to 24-holes culture dishes to grow up, EBs were treated by RA for 24 hours, then by nicotinamide. At present, there are the elementary results in the experiment, which will be checked up.Lastly, in my review there were two sources of islets cells--- pancreatic stem cells and...