Lack of agreement among two commercial enzyme-linked immunosorbent antibody assays and a conventional immunofluorescence-based method for detecting islet cell autoantibodies.
Two commercial enzyme-linked immunosorbent assays (ELISAs) for antibodies associated with development of insulin-dependent (type 1) diabetes mellitus (IDDM) were evaluated in conjunction with a conventional indirect immunofluorescent-antibody-islet cell antibody (ICA) test and a radioimmunoprecipitation method for detection of insulin autoantibodies in sera from a selected group of patients. The anti-ICA ELISA was positive for only 1 to 17 serum samples from newly diagnosed IDDM patients but yielded false-positive results with 2 of 6 serum samples containing non-diabetes-related autoantibodies. Although the anti-glutamic acid decarboxylase ELISA did not show positive results for sera with other autoantibodies, it was positive for only 4 of 29 serum samples from recently diagnosed IDDM patients and for 49% of 37 indirect immunofluorescent-antibody-ICA test-positive sera. Until the antibodies associated with the development of diabetes are better characterized, allowing better standards for comparison, it will be difficult to evaluate commercial assays in this field.
Baron
E J
EJ
Department of Medicine, University of California, Los Angeles, USA. ejbaron@ucia.edu
Weber
D E
DE
Weide
L G
LG
D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007158:Immunologic Techniques; D008297:Male; D011233:Precipitin Tests; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results
D001323:Autoantibodies; D011933:Reagent Kits, Diagnostic; C024211:islet cell antibody