title: Autoimmunity to islet proteins in children diagnosed with new-onset diabetes.
abstract: Autoantibody and T cells reacting with islet proteins have been demonstrated in patients with type 1 diabetes. In recent years an increasing number of children have been clinically classified with type 2 (not ketosis prone, evidence of insulin resistance, presence of acanthosis nigricans, and obesity) or indeterminant diabetes (admixture of clinical features of types 1 and 2). In this study, we compared the islet cell autoantibody and T-cell responses to islet proteins in type 2 (n = 19) and indeterminant (n = 16) children (<18 yr of age) to classic type 1 (n = 37) diabetic patients. We observed that 37 of 37 type 1 diabetic children demonstrated autoantibody and/or T-cell reactivity to islet proteins. Fourteen of the 19 type 2 patients were positive for islet cell autoantibodies, and six of 14 were positive for T-cell responses to islet proteins. For the indeterminant patients, 11 of 16 of the patients were positive for autoantibodies, and six of 16 patients were positive for T-cell responses to islet proteins. These results demonstrate that autoimmunity to islet proteins is present in a high percentage of children classified as indeterminant or type 2 diabetes. Moreover, the presence of obesity or acanthosis nigracans does not reliably distinguish children with or without islet cell autoimmunity.
authors.affiliation: Department of Medicine, University of Washington, Seattle, Washington 98195, USA. bbrooks@u.washington.edu
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Brooks-Worrell
authors.forename: Carla J
authors.initials: CJ
authors.lastname: Greenbaum
authors.forename: Jerry P
authors.initials: JP
authors.lastname: Palmer
authors.forename: Catherine
authors.initials: C
authors.lastname: Pihoker
mesh_terms: D001323:Autoantibodies / Q000032:analysis; D015551:Autoimmunity; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology*; D003924:Diabetes Mellitus, Type 2 / Q000276:immunology*; D005260:Female; D006801:Humans; D007515:Islets of Langerhans / Q000378:metabolism*; D008297:Male; D011506:Proteins / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D001323:Autoantibodies; D011506:Proteins; C024211:islet cell antibody