- Email: [email protected]
Adenoviral-Mediated Catalase Gene Transfer Protects Porcine and Human Islets In Vitro Against Oxidative Stress 1
Adenoviral-Mediated Catalase Gene Transfer Protects Porcine and Human Islets In Vitro Against Oxidative Stress P.Y. Benhamou, C. Moriscot, M.J. Richard, J. Kerr-Conte, F. Pattou, J. Chroboczek, P. Lemarchand, and S. Halimi
S
USCEPTIBILITY of pancreatic islets to oxidant stress may compromise islet viability and contribute to primary nonfunction of allogenic or xenogenic grafts. We investigated the influence of overexpression of catalase (CT) on the viability of porcine and human islets. Islets were incubated with a replication-deficient adenovirus vector containing the human CT cDNA under the control of an MLP promoter (AdCT), or a vector containing no foreign gene (AdNull) and used as a control. Oxidant stress was induced 48 hours later by xanthine oxidasehypoxanthine (XO 25 U/mL, HX 0.5 mmol/L) or hydrogen peroxide (100 or 250 mmol/L). Islet cell viability was assessed 72 hours after CT transfer by a quantitative colorimetric assay (WST-1 test). Baseline CT enzymatic activity was four-fold lower in porcine than in human islets. A three- to five-fold increase in CT activity was reproducibly observed in AdCT-infected porcine or human islets, as detected 48 hours after transfer and at least for 7 days. After XOHX exposure, human islet viability was decreased by 37 6 0.6% (controls), 34.6 6 2.1% (AdNull, P 5 ns),
© 1998 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010 Transplantation Proceedings, 30, 459 (1998)
26.2 6 2.4% (AdCT, P , .005 versus control). The same stress also decreased porcine islet viability by 60.1 6 0.9% (controls), 60.1 6 1.3% (AdNull, P 5 ns), 47.4 6 2.3% (AdCT, P , .005). Furthermore, under H2O2 exposure (250 mmol/L), human islet viability was decreased by 34.7 6 2.4% (controls) and 27.7 6 2% (AdCT, P , .05). A lower H2O2 stress (100 mmol/L) decreased porcine islet viability by 12.5 6 3.1% (controls) and 5.3 6 1.3% (AdCT, P , .05). We conclude that adenoviral-mediated CT gene transfer may be a realistic approach to protect human or porcine islet grafts against the adverse effects of nonspecific inflammation.
From the Department of Endocrinology, University Hospital, Grenoble, France. Supported by a grant from Fondation de l’Avenir, Re´gion Rhoˆne-Alpes and Alfediam. Address reprint requests to P.Y. Benhamou, Endocrinologie, CHU, BP 217X, 38043 Grenoble Cedex, France.
0041-1345/98/$19.00 PII S0041-1345(97)01355-9 459
S
USCEPTIBILITY of pancreatic islets to oxidant stress may compromise islet viability and contribute to primary nonfunction of allogenic or xenogenic grafts. We investigated the influence of overexpression of catalase (CT) on the viability of porcine and human islets. Islets were incubated with a replication-deficient adenovirus vector containing the human CT cDNA under the control of an MLP promoter (AdCT), or a vector containing no foreign gene (AdNull) and used as a control. Oxidant stress was induced 48 hours later by xanthine oxidasehypoxanthine (XO 25 U/mL, HX 0.5 mmol/L) or hydrogen peroxide (100 or 250 mmol/L). Islet cell viability was assessed 72 hours after CT transfer by a quantitative colorimetric assay (WST-1 test). Baseline CT enzymatic activity was four-fold lower in porcine than in human islets. A three- to five-fold increase in CT activity was reproducibly observed in AdCT-infected porcine or human islets, as detected 48 hours after transfer and at least for 7 days. After XOHX exposure, human islet viability was decreased by 37 6 0.6% (controls), 34.6 6 2.1% (AdNull, P 5 ns),
© 1998 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010 Transplantation Proceedings, 30, 459 (1998)
26.2 6 2.4% (AdCT, P , .005 versus control). The same stress also decreased porcine islet viability by 60.1 6 0.9% (controls), 60.1 6 1.3% (AdNull, P 5 ns), 47.4 6 2.3% (AdCT, P , .005). Furthermore, under H2O2 exposure (250 mmol/L), human islet viability was decreased by 34.7 6 2.4% (controls) and 27.7 6 2% (AdCT, P , .05). A lower H2O2 stress (100 mmol/L) decreased porcine islet viability by 12.5 6 3.1% (controls) and 5.3 6 1.3% (AdCT, P , .05). We conclude that adenoviral-mediated CT gene transfer may be a realistic approach to protect human or porcine islet grafts against the adverse effects of nonspecific inflammation.
From the Department of Endocrinology, University Hospital, Grenoble, France. Supported by a grant from Fondation de l’Avenir, Re´gion Rhoˆne-Alpes and Alfediam. Address reprint requests to P.Y. Benhamou, Endocrinologie, CHU, BP 217X, 38043 Grenoble Cedex, France.
0041-1345/98/$19.00 PII S0041-1345(97)01355-9 459