Comparison of a novel micro-assay for insulin autoantibodies with the conventional radiobinding assay

Diabetologia. 1998 Jun;41(6):681-3. doi: 10.1007/s001250050968.


Measurement of insulin autoantibodies (IAA) with a novel micro radiobinding assay which requires only 20 microl of serum was compared with that in a conventional radiobinding assay which uses 600 microl of serum. IAA were measured with both assays in samples from 94 new onset insulin-dependent diabetes mellitus (IDDM) patients, 97 control subjects. and 48 first degree relatives of IDDM patients selected for having IAA in the conventional radiobinding assay. Overall, 227 (95%) of 239 samples tested were concordant. and IAA levels correlated well (r2 = 0.7) between the two assays. Discordant results were obtained in 7 new onset patients, 4 control subjects, and 1 first degree relative, and these had low IAA levels in the respective assays. Sensitivity and specificity in the new onset IDDM patients and control subjects were 69% and 98% for the micro radiobinding assay and 72% and 98% for the conventional radiobinding assay. The use of the micro radiobinding assay should greatly facilitate islet related antibody screening, particularly in children.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Autoantibodies / blood*
  • Child
  • Child, Preschool
  • Diabetes Mellitus, Type 1 / blood
  • Female
  • Humans
  • Infant
  • Insulin / immunology*
  • Male
  • Microchemistry / methods*
  • Middle Aged
  • Radioligand Assay / methods
  • Sensitivity and Specificity


  • Autoantibodies
  • Insulin