این سایت در حال حاضر پشتیبانی نمی شود و امکان دارد داده های نشریات بروز نباشند
Cell Journal، جلد ۱۷، شماره Suppl ۱، صفحات ۱۳-۱۴
عنوان فارسی
چکیده فارسی مقاله
کلیدواژه‌های فارسی مقاله
عنوان انگلیسی Is-14: Islet Transplantation Using Differentiated Human Stem Cells
چکیده انگلیسی مقاله Diabetes is the 7th leading cause of death in the United States. Type 1 diabetes is an autoimmune disease where the body’s immune system destroys the specialized insulin- secreting cells in the islets of Langerhans, called β cells. Insulin is the primary hormone that regulates blood glucose levels. In the absence of insulin, blood glucose levels will rise. Islet allotransplantation involves the transplantation of islets harvested from human pancreas donors into diabetic recipients and has the potential to help type 1 diabetics to improve autonomous regulation of their blood sugar levels. The biggest drawback is the need for long-term immunosuppression. Islet encapsulation is a technique that can protect the islets within biocompatible microscale devices before transplantation. Encapsulating islets within permeable hydrogels such as alginate provides an effective immune barrier and allows to transplant without immunosuppression.In this study, we show that human embryonic stem cells derived-insulin-producing cells (hESC-IPCs) remain membrane viable and functional after alginate encapsulation and transplantation into diabetic rodents. The hESC-IPC clusters were derived using a proprietary feeder-free, enzymatic propagation method. Using this method, a process that can take 12-13 weeks in the fetus can be completed in 18 days. The clusters were then shipped to UC Irvine where they were encapsulated in 2.5% (w/v) ultra-pure low viscosity high mannuronate alginate microcapsules using an air-pressure driven electrostatic bead generator (Nisco Engineering AG) using optimized settings (Voltage: 9 kV, Pressure: 3 psi, Needle height: 30 mm, Needle gauge: 25G, Agitator speed: 80 rpm, Cross-linking solution: 120 mM CaCl2 ). After alginate encapsulation, the stem cells were allowed to recover overnight at 37oC, 5% CO2 in RPMI supplemented with 10% human AB serum. The hESC-IPC clusters were then characterized and analyzed for membrane viability and function. The percentage of viable hESC-IPCs was analyzed using yo-pro-1, propidium iodide and calcein blue, quantified with a microplate reader (TECAN) and imaged using a fluorescence microscope (Nikon TIE). Insulin release from hESC-IPCs was analyzed using a glucose-stimulated insulin response (GSIR) assay where known numbers of differentiated cell clusters were incubated for an hour each in the following solutions: low glucose (2.8 mM), high glucose (28 mM), high glucose + IBMX (28 mM +2 μM IBMX), and low glucose (2.8 mM). IBMX (3-isobutyl-1-methylxanthine) is an insulin secretagogue that further increases insulin release. The stimulation index (insulin release at high glucose concentrations /Insulin release at low glucose concentrations) and the maximum stimulation index (Insulin release at high glucose + IBMX/Insulin release at high glucose) was determined. Before encapsulation, the hESC-IPCs were 95.9 ± 0.02% viable and had a stimulation index (SI) of 0.57 ± 0.9. After alginate encapsulation, the viability was 93.9 ± 0.01% and the SI decreased to 0.25 ± 0.2. Statistical analysis demonstrated that alginate encapsulation did not negatively impact viability or function of the hESC-IPCs (P=0.38 and P=0.75 respectively). This indicates that the hESC-IPCs maintained viability and function after encapsulation. The hESC-IPCs maintained membrane viability and function after long-duration shipment and after encapsulation in alginate hydrogels. Studies that are currently underway include cellular characterization of hESC-IPCs using flow cytometry on free and alginate-encapsulated hESC-IPCs in order to evaluate the expression of insulin, glucagon and relevant stem cell markers in hESC-IPCs. This will be followed by in vivo studies where the encapsulated hESC-IPCs will be transplanted in diabetic mouse models to evaluate their efficacy.
کلیدواژه‌های انگلیسی مقاله
نویسندگان مقاله jrt lakey | jrt lakey


نشانی اینترنتی http://celljournal.org/journal/article/abstract/38
فایل مقاله فایلی برای مقاله ذخیره نشده است
کد مقاله (doi)
زبان مقاله منتشر شده en
موضوعات مقاله منتشر شده
نوع مقاله منتشر شده
برگشت به: صفحه اول پایگاه   |   نسخه مرتبط   |   نشریه مرتبط   |   فهرست نشریات