Comparison of a novel micro-assay for insulin autoantibodies with the conventional radiobinding assay.
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.
Naserke
H E
HE
Institute of Diabetes Research, Munich, Germany.
Dozio
N
N
Ziegler
A G
AG
Bonifacio
E
E
D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000097:blood; D005260:Female; D006801:Humans; D007223:Infant; D007328:Insulin / Q000276:immunology*; D008297:Male; D008832:Microchemistry / Q000379:methods*; D008875:Middle Aged; D011869:Radioligand Assay / Q000379:methods; D012680:Sensitivity and Specificity
D001323:Autoantibodies; D007328:Insulin