title: Induction of Ia antigen expression on murine islet parenchymal cells does not diminish islet allograft survival.
abstract: Aberrant Ia antigen expression has been implicated in the pathogenesis of type 1 diabetes. Ia antigen expression was induced on isolated B10.BR murine islet parenchymal cells by culturing them for 5 days with lymphokine supernatants containing interferon-gamma (IFN-gamma) or with recombinant murine IFN-gamma + recombinant tumor necrosis factor. Ia positivity was confirmed by indirect immunofluorescence. Islets cultured for 5 days without cytokines were Ia-negative. Purified B10.BR islets allografted into the portal veins of C57BL/6J mice do not reject, which allowed the authors to determine whether aberrant expression of Ia on parenchymal cells has a deleterious effect on allograft survival. Ia-positive or Ia-negative islets were transplanted via the portal vein into diabetic C57BL/6J mice. All mice remained normoglycemic until they were killed at 30 to 60 days. Well-granulated islet allografts were identified histologically in all mice. The experiment was repeated using Balb/cJ mice as donors. Purified Balb/cJ islets are rapidly rejected by C57BL/6J mice. Induction of Ia expression on Balb/cJ islets significantly improved allograft survival. These findings indicate that Ia-positive islet cells do not induce rejection in these allograft models but may actually have a protective effect.
authors.affiliation: Hospital for Children, Department of Pathology, Dalhousie University Faculty of Medicine, Nova Scotia, Canada.
authors.forename: J R
authors.initials: JR
authors.lastname: Wright
authors.forename: V
authors.initials: V
authors.lastname: Hauptfeld
authors.forename: P E
authors.initials: PE
authors.lastname: Lacy
mesh_terms: D000818:Animals; D006085:Graft Survival; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D007515:Islets of Langerhans / Q000166:cytology / Q000276:immunology*; D016381:Islets of Langerhans Transplantation; D008099:Liver / Q000473:pathology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D014184:Transplantation, Homologous
chemical_list: D000949:Histocompatibility Antigens Class II