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S-5-3 Superoxide scavengers prolong xenograft survival of microincapsulated canine islets (MECI) in nod mice
S-5-3 SUPEROXIDE SCAVENGERS PROLONG XENOGRAFT SURVIVAL OF MICROINCAPSULATED
CANINE
ISLETS (MECI) IN NOD MICE R. Calafiore, F. Calcinaro, G. Basta, *N. Koh and *R. Alejandro Istituto di Patologia Medica, University of Perugia, Perugia, Italy and Diabetes Research Institute, University of Miami, Miami, U.S.A. We showed that xenotransplantation of MECI in poly-L-ornithine-Na alginate biomembranes into NOD mice resulted in transient reversal of diabetes: n=ll FBG 574~34 mg/dl, day O; ll/ll euglycemic (E), FBG 84~7 mg/dl, day 3; 4/11 E, 83~8 mg/dl, day 7 post-transplant (pTx). To evaluate whether we could prolong MECI graft survival we divided xenotransplanted NOD mice in two groups: i) n=9 (starting FBG 525~38 mg/dl) received Cyclosporine A (CSA), 75 mg/Kg/day, subcutaneously; 2) n=13 (starting FBG 574+36 mg/dl) were treated with free oxygen radical scavengers, polyethylene glycol conjugated superoxide dismutase and catalase (PEG-SOD/CAT, I0.000 UI/50.O00 UI/Kg/day intraperitoneally). Results: i) 9/9 E, FBG 90~6 mg/dl, day 3; 3/9 E, FBG 93~3 mg/dl,day 7 pTx. 2) 13/13 E, FBG 88~6 mg/dl, day 3; 13/13 E, FBG 91~6 mg/dl, day 7 pTx. Conclusions: PEG-SOD/CAT but not CSA afforded complete protection of MECI xenograft in NOD mice during the first 7 days of transplantation suggesting that free oxygen radical generation may compromise graft survival in the peritransplant period.
S-5-4 SOPHISTICATED TECHNIQUE OF A LARGE SCALE ISOLATION OF ISLETS AND THEIR FUNCTION Y. Hara, H. Taniguchi, K. Ishihara, K. Ejiri, A. Tsutou, S.J. Shin, K. Narutaki* and S. Baba Second Department of Internal Medicine, Kobe University School of Medicine and *Hyogo Rehabilitation Center, Kobe, Japan A large scale isolation of islets is required for animal studies that are mandatory prior to human application of islet transplantation. In the present paper we report a sophisticated method. (Method) Pancteata of adult Wistar rats were inflated by injection of buffer with (A) or without 1.3mg/ml collagenase (B), with simultaneous bleeding from the inferior vena eava in A. They were further digested with eollagenase and filtered through two meshes (pore size: 1190 and 590um) (AI) and additional mesh (pore size: lOOum) (AII). Insulin released from thus isolated islets were determined after one hour incubation with 3.3 and 16.7mM glucose. Besides, each 600 islets were transplanted into the liver of streptozotocin-induced diabetic Wistar rats and their fasting plasma glucose was measured at a weekly interval. (Results) (i) More numerous islets were harvested by AI (mean: 554) and AII (mean: 750) than C (mean: 224). (2) Insulin release at both glucose concentrations were similar among AI, AII and C. (3) Plasma glucoselowering effect was similar among the islets obtained by these methods. (Conclusion) The present technique (AI and AII) are less time-consuming and simple for a large scale isolation of islets.
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CANINE
ISLETS (MECI) IN NOD MICE R. Calafiore, F. Calcinaro, G. Basta, *N. Koh and *R. Alejandro Istituto di Patologia Medica, University of Perugia, Perugia, Italy and Diabetes Research Institute, University of Miami, Miami, U.S.A. We showed that xenotransplantation of MECI in poly-L-ornithine-Na alginate biomembranes into NOD mice resulted in transient reversal of diabetes: n=ll FBG 574~34 mg/dl, day O; ll/ll euglycemic (E), FBG 84~7 mg/dl, day 3; 4/11 E, 83~8 mg/dl, day 7 post-transplant (pTx). To evaluate whether we could prolong MECI graft survival we divided xenotransplanted NOD mice in two groups: i) n=9 (starting FBG 525~38 mg/dl) received Cyclosporine A (CSA), 75 mg/Kg/day, subcutaneously; 2) n=13 (starting FBG 574+36 mg/dl) were treated with free oxygen radical scavengers, polyethylene glycol conjugated superoxide dismutase and catalase (PEG-SOD/CAT, I0.000 UI/50.O00 UI/Kg/day intraperitoneally). Results: i) 9/9 E, FBG 90~6 mg/dl, day 3; 3/9 E, FBG 93~3 mg/dl,day 7 pTx. 2) 13/13 E, FBG 88~6 mg/dl, day 3; 13/13 E, FBG 91~6 mg/dl, day 7 pTx. Conclusions: PEG-SOD/CAT but not CSA afforded complete protection of MECI xenograft in NOD mice during the first 7 days of transplantation suggesting that free oxygen radical generation may compromise graft survival in the peritransplant period.
S-5-4 SOPHISTICATED TECHNIQUE OF A LARGE SCALE ISOLATION OF ISLETS AND THEIR FUNCTION Y. Hara, H. Taniguchi, K. Ishihara, K. Ejiri, A. Tsutou, S.J. Shin, K. Narutaki* and S. Baba Second Department of Internal Medicine, Kobe University School of Medicine and *Hyogo Rehabilitation Center, Kobe, Japan A large scale isolation of islets is required for animal studies that are mandatory prior to human application of islet transplantation. In the present paper we report a sophisticated method. (Method) Pancteata of adult Wistar rats were inflated by injection of buffer with (A) or without 1.3mg/ml collagenase (B), with simultaneous bleeding from the inferior vena eava in A. They were further digested with eollagenase and filtered through two meshes (pore size: 1190 and 590um) (AI) and additional mesh (pore size: lOOum) (AII). Insulin released from thus isolated islets were determined after one hour incubation with 3.3 and 16.7mM glucose. Besides, each 600 islets were transplanted into the liver of streptozotocin-induced diabetic Wistar rats and their fasting plasma glucose was measured at a weekly interval. (Results) (i) More numerous islets were harvested by AI (mean: 554) and AII (mean: 750) than C (mean: 224). (2) Insulin release at both glucose concentrations were similar among AI, AII and C. (3) Plasma glucoselowering effect was similar among the islets obtained by these methods. (Conclusion) The present technique (AI and AII) are less time-consuming and simple for a large scale isolation of islets.
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