A new luminescence assay for autoantibodies to mammalian cell-prepared insulinoma-associated protein 2.
OBJECTIVE
Insulinoma-associated protein 2 (IA-2) is a major autoantigen in type 1 diabetes, and IA-2 autoantibodies are routinely detected by a liquid-phase radioimmunoprecipitation assay. The present experiments were initiated to develop a new assay that does not require the use of radioisotopes or autoantigens prepared in bacteria or by in vitro transcription/translation.


METHODS
IA-2 luciferase fusion protein was expressed in mammalian cells and assayed for autoantibodies by liquid-phase luciferase immunoprecipitation.


RESULTS
Our study showed that there was no significant difference between the luciferase immunoprecipitation and the radioimmunoprecipitation assays in sensitivity and specificity, and comparison of the two assays revealed a high correlation coefficient (R(2) = 0.805).


CONCLUSIONS
The luciferase system offers a robust, inexpensive, nonradioactive method for the detection of autoantibodies to mammalian cell-prepared IA-2 and could be of practical value at the clinical level.
Sensory Biology Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, USA.
Peter D
PD
Burbelo
Hiroki
H
Hirai
Hannah
H
Leahy
Ake
A
Lernmark
Sten A
SA
Ivarsson
Michael J
MJ
Iadarola
Abner Louis
AL
Notkins
D000818:Animals; D001323:Autoantibodies / Q000097:blood*; D001324:Autoantigens; D019556:COS Cells; D002522:Chlorocebus aethiops; D003920:Diabetes Mellitus / Q000097:blood*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000276:immunology; D000882:Haplorhini; D006801:Humans; D049449:Luminescence; D054635:Receptor-Like Protein Tyrosine Phosphatases, Class 8 / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology
D001323:Autoantibodies; D001324:Autoantigens; D011994:Recombinant Proteins; D054635:Receptor-Like Protein Tyrosine Phosphatases, Class 8