title: Insulin-like growth factor-1 (IGF-1)-derived peptide protects against diabetes in NOD mice.
abstract: Spontaneous diabetes in non-obese diabetic (NOD) mice results from beta-cell destruction by autoreactive T lymphocytes. Here, we report the significance of insulin-like growth factor-1 (IGF-1) peptide as a tool for the prevention of type 1 diabetes. Female NOD mice were immunized with a subcutaneous injection of IGF-1, glutamic acid decarboxylase (GAD), insulin or IGF-1-derived peptides (residues 8-23, 24-41 or 50-70) in incomplete Freund's adjuvant (IFA) or with IFA only as the control group at 4 weeks of age, and observed up to 36-37 weeks of age. Diabetes onset was significantly suppressed and delayed in the IGF-1 group as compared to the GAD, insulin and control groups (p<0.05), and it was significantly suppressed and delayed in the (50-70)IGF-1 group as compared to the (8-23)IGF-1 and control groups (p<0.02). Although the degree of insulitis in all treated mice was not significantly different, a significant number of IL-4-producing cells in response to IGF-1 peptides were detected in (50-70)IGF-1-treated mice in intracellular cytokine assay. In conclusion, IGF-1 peptide 50-70 immunizations of NOD mice suppressed and delayed diabetes onset, probably through amplification of the Th2-type response. It was suggested that IGF-1 peptide 50-70 immunization can be used as a tool for prevention of type 1 diabetes.
authors.affiliation: Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Kodama
authors.forename: Akira
authors.initials: A
authors.lastname: Shimada
authors.forename: Osamu
authors.initials: O
authors.lastname: Funae
authors.forename: Jiro
authors.initials: J
authors.lastname: Morimoto
authors.forename: Junichiro
authors.initials: J
authors.lastname: Irie
authors.forename: Toshikatsu
authors.initials: T
authors.lastname: Shigihara
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Oikawa
authors.forename: Mikiya
authors.initials: M
authors.lastname: Tokui
authors.forename: Kenji
authors.initials: K
authors.lastname: Watanabe
authors.forename: Takao
authors.initials: T
authors.lastname: Saruta
mesh_terms: D000367:Age Factors; D000818:Animals; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy / Q000276:immunology / Q000517:prevention & control*; D005260:Female; D007334:Insulin-Like Growth Factor I / Q000235:genetics; D051379:Mice; D016688:Mice, Inbred NOD; D010446:Peptide Fragments / Q000235:genetics / Q000627:therapeutic use*; D018418:Th2 Cells / Q000187:drug effects
chemical_list: D010446:Peptide Fragments; D007334:Insulin-Like Growth Factor I