Experimental Studies On Induction Of Embryonic Stem Cells To Insulin Producing Cells And Cell Transplantation Therapy Of Diabetes Mellitus

Embryonic stem cells (ES) are totipotent stem cells originated from inner cell mass of early embryos. They possess the capabilities to differentiate into various cell and tissue types desired, which can be used for cell or tissue-based therapy to cure some diseases. Diabetes mellitus (DM) is a disorder characterized by the autoimmune destruction of insulin-producingβ-cells in the pancreastic islets or insulin-resistance, which resulting in insulin deficiency absolutely or relatively. Exogenous insulin-supplement is a classic method for the treatment of type I DM(T1DM). Insulin administration may relief complications from hyperglycaemia, but DM can not be cure ultimately. It may be a promise alternative for DM therapy to induce ES differentiate into insulin-producing cells(IPC) and to implant the IPC into DM patients.It was showed that ES cells could be induced to IPC, which relief the symptoms of DM after IPC transplantation. It brings a prospect of DM therapy. But some inadequacies are existing at present, such as low numbers, poor function and complex processing of IPC inducing. These defects prevent the IPC-based therapy from their clinic application.Pancreas duodenum homeobox-1(pdx-1) gene plays key roles in the development of pancrease and differentiation of pancreatic-cells in embryogenesis. It is also indispensable to maintain islet function in adult. It may improve the yield and the function of IPC to transfecte pdx-1 into ES and make pdx-1 overexpression. We therefore built a new pdx-1 gene vector with enhance green fluorescence protein (EGFP) report gene, pEGFP/pdx-1, and pdx-1 gene was then transfected into ES cells by liposome. IPC inducing strategies were modified in our studies in order to improve IPC output and insulin secreting level of IPC. The main results were as follows:1. Purified mouse embryonic fibroblasts (MEF) were isolated from pregnant mouse to prepare feeder layer for ES culture in first part of our research. It was found that 13.5...