Logo Annals of Transplantation Logo Annals of Transplantation Logo Annals of Transplantation

12 September 1997

Characterization and transplantation of agarose microencapsulated canine islets of langerhans

Hideo Tashiro, Hiroo Iwata, Garth L Warnock, Tatsuya Takagi, Hirohisa Machida, Yoshito Ikada, Takayuki Tsuji

Ann Transplant 1997; 2(3): 33-39 :: ID: 497170

Abstract

The bioartificial pancreas was designed to incorporate islet tissues and a selectively permiable membrane that isolates islets from the immune system of the recipient. The efficacy of agarose, a nontoxic polysaccharide, has been evaluated as a material of microcapsules to prevent allo- and xenograft rejection in rodents. The aim of this study is to demonstrate the possibility of the agarose microcapsule containing allo-islets as a bioartificial pancreas in canine model. In vitro viabilityof islets was determined by glucose challenge during perifusion experiments (n=4). Insulinsecretion from both encapsulated (enc.) and non-encapsulated (non-enc.) canine islets rose from initial basal levels of 0.09(encap.), 0.07(non-encap.)to the peak of 0.2(encap.), 0.1(non-encap.) in pU/islet/min after 5 minutes, then decreased to the basal level when the glucose challenge was discontinued. Auto-transplantation was performed in two dogs to evaluated in vivo viabilityand biocompatibility of encapsulated islets implanted into the splenic sinus by venouse reflux. Two weeks after auto-transplantation, the plasma insulin levels in the splenic vein and artery of two dogs were assayed. In the first dog, serum insulin level was IpU/ml both in the vein and the artery and increased, after glucagon (I.Omg) injection, to levels of 9 pU/ml in the vein, but still kept I pU/ml in artery, as well as in the second one. Histological and electron-microscopical examination of the spleen revealed that encapsulated islets remained morphologically intact and the surface of agarose capsules showed no significant adherence of fibroblasts and inflammatory cells. Functional efficacy of the microencapsulated islets was determined using five totally-pancreatectomized diabetic dogs as recipients without immunosuppression. Defined quantitiy of microencapsulated islets from outbred mongrel donors were grafted through the catheter into omental tissue of the pancreatectomized recipients. All dogs had various degrees of reduced insulin requirements. In three of five recipients, the average fasting glucose values were controlled under 120 mg/dl for 28, 42, 49 days without exogenous insulin, which recieved totally4.3x 103, 7.3x 103 and 1.0x 104 (IE/kg) of microencapsulated islets, respectively. In conclusion, the present study indicates that the agarose-based microencapsulated islets can function in large diabetic animals, resulting in the independence of exogenous insulin therapy for prolonged periods without the need for immunosuppression.

Keywords: bioartificial, agarose, islet, Transplantation, diabetes, microencapsulation, Pancreas

0 Comments

Most Viewed Current Articles

26 Jan 2022 : Review article  

Recurrence of Hepatocellular Carcinoma After Liver Transplantation: Risk Factors and Predictive Models

DOI :10.12659/AOT.934924

Ann Transplant 2022; 27:e934924

24 Aug 2021 : Review article  

Normothermic Machine Perfusion (NMP) of the Liver – Current Status and Future Perspectives

DOI :10.12659/AOT.931664

Ann Transplant 2021; 26:e931664

29 Dec 2021 : Original article  

Efficacy and Safety of Tacrolimus-Based Maintenance Regimens in De Novo Kidney Transplant Recipients: A Sys...

DOI :10.12659/AOT.933588

Ann Transplant 2021; 26:e933588

15 Mar 2022 : Case report  

Combined Liver, Pancreas-Duodenum, and Kidney Transplantation for Patients with Hepatitis B Cirrhosis, Urem...

DOI :10.12659/AOT.935860

Ann Transplant 2022; 27:e935860

Your Privacy

We use cookies to ensure the functionality of our website, to personalize content and advertising, to provide social media features, and to analyze our traffic. If you allow us to do so, we also inform our social media, advertising and analysis partners about your use of our website, You can decise for yourself which categories you you want to deny or allow. Please note that based on your settings not all functionalities of the site are available. View our privacy policy.

Annals of Transplantation eISSN: 2329-0358
Annals of Transplantation eISSN: 2329-0358