title: A strategy for the engineering of insulin producing cells with a broad spectrum of defense properties.
abstract: Insulin-producing pancreatic beta cells are known to be extremely susceptible to the oxidative stress and hypoxia generated following islet transplantation in diabetic patients. We hereby present a novel in vivo selection strategy based on the isolation of insulin-producing cells with enhanced protection after repeated rounds of encapsulation and xenotransplantation. Rat insulinoma INS-1 cells were encapsulated in alginate macrobeads and transplanted in the peritoneal cavity of mice. After 2 days the beads were retrieved and cells were recovered from alginate and propagated in vitro until submitted to a second round of encapsulation and transplantation. Three days later, the surviving cells, named INS-1m2, were isolated from the alginate beads and their protection and functional activity examined. Compared to parental INS-1 cells, the selected INS-1m2 cells were more resistant to hydrogen peroxide, nitric oxide, alloxan and hypoxia. This enhanced protection of the selected cells correlated with the increased level of catalase and poly (ADP-ribose) polymerase expression. Although selected cells expressed more insulin than parental cells, no change in their insulin response to glucose was observed. We conclude that the in vivo selection strategy is a powerful tool for the engineering of insulin producing cells with a broad spectrum of defense properties.
authors.affiliation: Diabetes and Obesity Research Laboratory, Felsenstein Medical Research Center, Sackler Faculty of Medicine, Tel-Aviv University, Beilinson Campus, Petah Tikva 49100, Israel. kbloch@post.tau.ac.il
authors.forename: Konstantin
authors.initials: K
authors.lastname: Bloch
authors.forename: Olga
authors.initials: O
authors.lastname: Bloch
authors.forename: Igor
authors.initials: I
authors.lastname: Tarasenko
authors.forename: Daniel
authors.initials: D
authors.lastname: Lazard
authors.forename: Micha
authors.initials: M
authors.lastname: Rapoport
authors.forename: Pnina
authors.initials: P
authors.lastname: Vardi
mesh_terms: D000464:Alginates / Q000737:chemistry; D000818:Animals; D017209:Apoptosis / Q000235:genetics / Q000502:physiology; D001786:Blood Glucose / Q000378:metabolism; D015153:Blotting, Western; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D064987:Cell- and Tissue-Based Therapy / Q000379:methods*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D007150:Immunohistochemistry; D007328:Insulin / Q000378:metabolism; D050417:Insulin-Secreting Cells / Q000166:cytology* / Q000378:metabolism; D008297:Male; D051379:Mice; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D051381:Rats
chemical_list: D000464:Alginates; D001786:Blood Glucose; D006603:Hexuronic Acids; D007328:Insulin; D019253:Proto-Oncogene Proteins c-bcl-2; D020723:Glucuronic Acid; D011065:Poly(ADP-ribose) Polymerases