Thursday, November 9, 2017

PLGA-PEG-NHS from PolySciTech used as part of nanoparticle-protected-islets based treatment of diabetes


Type 1 Diabetes is a chronic disease brought on by loss of function of pancreatic islets, groups of cells that produce insulin to regulate the blood sugar content. Recently, transplantation of pancreatic islets has been considered as a long-term treatment for type 1 diabetes that does not require the patient to take daily injections of insulin. Immune-system rejection of the transplant, however, creates difficult for this treatment method as the body attacks the newly transplanted cells. One means of preventing this is to encapsulate the cells in a material which is non-immunogenic so as to protect them from macrophages. Recently, researchers at Yeungnam University, Seoul National University, and Keimyung University (Korea) utilized PolyVivo AI111 (PLGA-PEG-NHS) from PolySciTech (www.polyscitech.com) to create pegylated nanoparticles which attach to the islet cells and prevent them from being attacked by the immune system. This research holds promise to provide for a long-term treatment of diabetes which does not require the patient to continuously inject insulin. Read more: Pham, Tung Thanh, Tiep Tien Nguyen, Shiva Pathak, Shobha Regmi, Hanh Thuy Nguyen, Tuan Hiep Tran, Chul Soon Yong et al. "Tissue adhesive FK506–loaded polymeric nanoparticles for multi–layered nano–shielding of pancreatic islets to enhance xenograft survival in a diabetic mouse model." Biomaterials (2017). http://www.sciencedirect.com/science/article/pii/S014296121730707X

“Abstract: This study aims to develop a novel surface modification technology to prolong the survival time of pancreatic islets in a xenogenic transplantation model, using 3,4–dihydroxyl–l–phenylalanine (DOPA) conjugated poly(lactide–co–glycolide)–poly(ethylene glycol) (PLGA–PEG) nanoparticles (DOPA–NPs) carrying immunosuppressant FK506 (FK506/DOPA–NPs). The functionalized DOPA–NPs formed a versatile coating layer for antigen camouflage without interfering the viability and functionality of islets. The coating layer effectively preserved the morphology and viability of islets in a co–culture condition with xenogenic lymphocytes for 7 days. Interestingly, the mean survival time of islets coated with FK506/DOPA–NPs was significantly higher as compared with that of islets coated with DOPA–NPs (without FK506) and control. This study demonstrated that the combination of surface camouflage and localized low dose of immunosuppressant could be an effective approach in prolonging the survival of transplanted islets. This newly developed platform might be useful for immobilizing various types of small molecules on therapeutic cells and biomaterial surface to improve the therapeutic efficacy in cell therapy and regenerative medicine. Keywords: Surface modification; FK506; Islets transplantation; Local delivery; Diabetes mellitus”

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