Effect of Micro- and Macroencapsulation on Oxygen Consumption by Pancreatic Islets

Cell Transplantation

Article

Roberta Cornolti¹  Marina Figliuzzi¹  Andrea Remuzzi² 

[1] Department of Biomedical Engineering, Mario Negri Institute for Pharmacological Research, Bergamo, Italy;Department of Biomedical Engineering, Mario Negri Institute for Pharmacological Research, Bergamo, Italy;Department of Industrial Engineering, Faculty of Engineering, University of Bergamo, Dalmine (BG), Italy;

关键词: Oxygen consumption rate;    Immunoisolation;    Bovine pancreatic islet;    Microcapsule;    Hollow fiber;   

DOI  :  10.3727/096368909788341252

 received in 2008-02-13, accepted in 2008-08-28,  发布年份 2009

来源: Sage Journals

【 摘 要 】

Immunoisolation of pancreatic islets is extensively investigated for glycemic control in diabetic experimental animals. We previously reported that subcutaneous xenotransplantation of bovine islets protected by a selective polysulfone membrane successfully controlled glycemia in diabetic rats for up to 20 days. We then wondered whether immunoisolated islets have adequate oxygen supply in this device, where only diffusive transport allows cell function and survival. Here we set up an experimental technique to measure oxygen consumption rate (OCR) using a Clark's electrode inserted in a glass thermostated chamber connected to a data recorder and acquisition system. Bovine islets were isolated from 6-month-old calves, encapsulated in sodium alginate microcapsules or inserted in polysulfone hollow fibers. After 1 and 2 days in culture a series of measurements was performed using free islets (at normal or high-glucose concentration), islets encapsulated in microcapsules, or in hollow fibers. In free islets OCR averaged from 2.0 ± 0.8 pmol/IEQ/min at low-glucose concentration and from 2.5 ± 1.0 pmol/IEQ/min at high-glucose concentration (p < 0.01). OCR in islets encapsulated in microcapsules and in hollow fibers was comparable, and not significantly different from that measured in free islets. Two days after isolation OCR averaged 2.3 ± 0.6 in free islets, 2.3 ± 0.9 in alginate microcapsules, and 2.2 ± 0.7 pmol/IEQ/min in hollow fibers. These results show that OCR by bovine islets is comparable to that previously reported for other species. OCR increases in islets stimulated with high glucose and may be considered as a functional index. Moreover, islet encapsulation in alginate microcapsule, as well as in hollow fiber membranes, did not significantly affect in vitro OCR, suggesting adequate islet oxygenation in these conditions.

【 授权许可】

Unknown   
© 2009 Cognizant Comm. Corp.

【 图 表 】

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