Browsing by Author "Muthyala, Sudhakar"

Now showing 1 - 2 of 2
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    Cytocompatibility studies of mouse pancreatic islets on gelatin-PVP semi IPN scaffolds in vitro Potential implication towards pancreatic tissue engineering
    (ISLETS, 2010)
    Type 1 diabetes is a chronic disorder that results due to auto immune destruction of insulin producing cells, which leads to hyperglycemia in the blood. The development of an ideal scaffold for maintaining the structure and function of islets is a challenge in the field of pancreatic tissue engineering. In this study, gelatin (G) as well as gelatin/PVP (GP) semi interpenetrating polymer network scaffolds have been fabricated by freeze drying technique and cross linked with gluteraldehyde (GTA) and 1-Ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDC), which was abbreviated as GG, GPG (cross linked with GTA) GE and GPE (cross linked with EDC). The presence of gelatin and PVP in GPE and GPG scaffolds was confirmed through FTIR and TGA. The medium uptake ability of GPE and GPG scaffolds were higher than GG and GE scaffolds. The scaffolds were then analyzed for its ability to maintain the viability and function of mouse pancreatic islet cells in vitro. The results showed that the islets can adhere, but they tend to lose the structure and function on all the scaffolds after day 7, except on GPE where they remained intact up to day 30. Thus the present study clearly demonstrates that gelatin incorporated with PVP and cross linked with EDC scaffolds could support and maintain islet cells for prolonged period.
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    The reversal of diabetes in rat model using mouse insulin producing cells - A combination approach of tissue engineering and macroencapsulation
    (ACTA BIOMATERIALIA, 2011)
    Type 1 diabetes is a chronic disorder resulting from the autoimmune destruction of insulin-producing cells, a leading cause of morbidity and mortality all over the world. In this study a tissue engineering approach was compared with a macroencapsulation approach to reverse type 1 diabetes in a rat model. using mouse pancreatic progenitor cell (PPC)-derived islet-like clusters and mouse islets. For the tissue engineering approach the cells were cultured on gelatin scaffolds cross-linked with EDC in the presence of polyvinylpyrrolidone in vitro (GPE scaffolds), while for the macroencapsulation approach the cells were encapsulated in polyurethane-polyvinylpyrrolidone semi-Interpenetrating networks. In the combination approach the cells cultured on GPE scaffolds were further encapsulated in a polyurethane-polyvinylpyrrolidone capsule. Real time PCR studies and the glucose challenge assay have shown that cells on GPE scaffolds could express and secrete insulin and glucagon in vitro. However, under in vivo conditions the animals treated by the tissue engineering approach died within 15-20 days and showed no reversal of their diabetes, due to infiltration of immune cells such as CD4 and CD8 cells and macrophages. In the macroencapsulation approach the animals showed euglycemia within 25 days, which was maintained for further 20 days, but after that the animals died. Interestingly, in the combination approach the animals showed reversal of hyperglycemia, and remained euglycemic for up to 3 months. The time needed to achieve initial euglycemia was different with different cell types, i e. the combination approach with mouse Islets achieved euglycemia within 15 days, whereas with PPC-derived islet-like clusters euglycemia was achieved within 25 days This study confirmed that a combination of tissue engineering and macroencapsulation with mouse islets could reverse diabetes and maintain euglycemia in an experimental diabetes rat model for 90 days. (C) 2011 Acta Materialia Inc Published by Elsevier Ltd All rights reserved