title: Active tolerance induction and prevention of autoimmune diabetes by immunogene therapy using recombinant adenoassociated virus expressing glutamic acid decarboxylase 65 peptide GAD(500-585).
abstract: Tolerance induction of autoreactive T cells against pancreatic beta cell-specific autoantigens such as glutamic acid decarboxylase 65 (GAD65) and insulin has been attempted as a method to prevent autoimmune diabetes. In this study, we investigate whether adenoassociated virus (AAV) gene delivery of multiple immunodominant epitopes expressing GAD(500-585) could induce potent immune tolerance and persistently suppress autoimmune diabetes in NOD mice. A single muscle injection of 7-wk-old female NOD mice with rAAV/GAD(500-585) (3 x 10(11) IU/mouse) quantitatively reduced pancreatic insulitis and efficiently prevented the development of overt type I diabetes. This prevention was marked by the inactivation of GAD(500-585)-responsive T lymphocytes, the enhanced GAD(500-585)-specific Th2 response (characterized by increased IL-4, IL-10 production, and decreased IFN-gamma production; especially elevated anti-GAD(500-585) IgG1 titer; and relatively unchanged anti-GAD(500-585) IgG2b titer), the increased secretion of TGF-beta, and the production of protective regulatory cells. Our studies also revealed that peptides 509-528, 570-585, and 554-546 in the region of GAD(500-585) played important roles in rAAV/GAD(500-585) immunization-induced immune tolerance. These data indicate that using AAV, a vector with advantage for therapeutic gene delivery, to transfer autoantigen peptide GAD(500-585), can induce immunological tolerance through active suppression of effector T cells and prevent type I diabetes in NOD mice.
authors.affiliation: Department of Molecular Immunology, Institute of Basic Medical Sciences, Beijing, People's Republic of China.
authors.forename: Gencheng
authors.initials: G
authors.lastname: Han
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Jianan
authors.initials: J
authors.lastname: Wang
authors.forename: Renxi
authors.initials: R
authors.lastname: Wang
authors.forename: Guojiang
authors.initials: G
authors.lastname: Chen
authors.forename: Lun
authors.initials: L
authors.lastname: Song
authors.forename: Ruonan
authors.initials: R
authors.lastname: Xu
authors.forename: Ming
authors.initials: M
authors.lastname: Yu
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Wu
authors.forename: Jiahua
authors.initials: J
authors.lastname: Qian
authors.forename: Beifen
authors.initials: B
authors.lastname: Shen
mesh_terms: D000818:Animals; D001324:Autoantigens / Q000235:genetics; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D000229:Dependovirus / Q000235:genetics; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology* / Q000517:prevention & control*; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D005968:Glutamate Decarboxylase / Q000235:genetics* / Q000276:immunology*; D007108:Immune Tolerance; D066298:In Vitro Techniques; D007515:Islets of Langerhans / Q000201:enzymology / Q000276:immunology; D007527:Isoenzymes / Q000235:genetics* / Q000276:immunology*; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D010446:Peptide Fragments / Q000235:genetics / Q000276:immunology; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D014611:Vaccination
chemical_list: D001324:Autoantigens; D007527:Isoenzymes; D010446:Peptide Fragments; D011994:Recombinant Proteins; D005968:Glutamate Decarboxylase; C401141:glutamate decarboxylase 2