Species-specific autoantibodies in type 1 diabetes

J Clin Endocrinol Metab. 1999 Feb;84(2):643-8. doi: 10.1210/jcem.84.2.5503.

Abstract

GAD65 autoantibodies (GAD65Ab) are important markers for type 1 (insulin-dependent) diabetes mellitus. Although most patients have GAD65Ab at the time of clinical diagnosis, there are also GAD65Ab-positive individuals in the population at low risk of developing type 1 diabetes. The aim of this study was to test the hypothesis that the GAD65Ab reactivity to GAD65 cloned from human, mouse, and rat in newly diagnosed type 1 diabetic patients differ from antibody-positive healthy individuals. Sera from 254 new-onset 0- to 34-yr-old type 1 diabetic patients and 270 controls were assayed for their reactivity to human, mouse, and rat GAD65. Among the type 1 diabetic patients there was a significant better binding of human GAD65 compared to either mouse (P = 0.03) or rat GAD65 (P = 0.0005). The preference for human GAD65 increased with increasing age at onset (P = 0.0002). This differentiation was not observed in 88 GAD65Ab-positive control subjects. Our data indicate that recognition of epitopes by GAD65Ab in type 1 diabetes is different from that in nontype 1 diabetes, GAD65Ab-positive individuals.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aging
  • Amino Acid Sequence
  • Animals
  • Autoantibodies / blood*
  • Autoantigens / immunology
  • Diabetes Mellitus, Type 1 / immunology*
  • Glutamate Decarboxylase / chemistry
  • Glutamate Decarboxylase / immunology
  • Humans
  • Insulin / immunology
  • Isoenzymes / immunology
  • Mice
  • Molecular Sequence Data
  • Molecular Weight
  • Peptide Fragments / immunology
  • Protein Denaturation
  • Rats
  • Sequence Alignment
  • Species Specificity

Substances

  • Autoantibodies
  • Autoantigens
  • Insulin
  • Isoenzymes
  • Peptide Fragments
  • Glutamate Decarboxylase