Clinical Chemistry
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Clinical Chemistry 49: 916-923, 2003; 10.1373/49.6.916
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Web of Science (5)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Westerlund-Karlsson, A.
Right arrow Articles by Hinkkanen, A. E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Westerlund-Karlsson, A.
Right arrow Articles by Hinkkanen, A. E.
Related Collections
Right arrow Clinical Immunology
Right arrow Endocrinology and Metabolism
Right arrow Automation and Analytical Techniques
(Clinical Chemistry. 2003;49:916-923.)
© 2003 American Association for Clinical Chemistry, Inc.

Detection of Autoantibodies to Protein Tyrosine Phosphatase-like Protein IA-2 with a Novel Time-resolved Fluorimetric Assay

Annette Westerlund-Karlsson1,a, Katriina Suonpää2, Matti Ankelo1, Jorma Ilonen3, Mikael Knip4,5 and Ari E. Hinkkanen1

1 Department of Biochemistry and Pharmacy, Åbo Akademi University, FIN-20521 Turku, Finland.

2 PerkinElmer Life and Analytical Sciences, Wallac Oy, FIN-20520 Turku, Finland.

3 Department of Virology, University of Turku, FIN-20520 Turku, Finland.

4 Hospital for Children and Adolescents, University of Helsinki, FIN-00014 Helsinki, Finland.

5 Department of Pediatrics, Tampere University Hospital, FIN-33521 Tampere, Finland.

aAddress correspondence to this author at: Department of Biochemistry and Pharmacy, Åbo Akademi University, PO Box 66, FIN-20521 Turku, Finland. Fax 358-2-2154745; e-mail awesterl{at}abo.fi.

Background: Circulating autoantibodies to pancreatic glutamic acid decarboxylase (GAD65; the 65-kDa isoform of glutamic acid decarboxylase), protein tyrosine phosphatase-like protein IA-2, and insulin can be used as predictive markers of type 1 diabetes. We developed a novel assay for the detection of IA-2 autoantibodies (IA-2As) in serum based on time-resolved fluorimetry, hypothesizing that this kind of assay could provide several advantages over methods described to date, including radiobinding assays (RBAs) and ELISAs.

Methods: The intracellular part of IA-2 (IA-2ic) was biotinylated and bound to streptavidin-coated 96-well plates by simultaneous incubation with serum samples and glutathione S-transferase (GST)-IA-2ic fusion protein. GST-IA-2ic captured by autoantibodies in the serum was detected with europium-labeled anti-GST antibody, and the signal was measured in a time-resolved fluorimeter. A serum sample panel from 100 patients with newly diagnosed type 1 diabetes and 100 unaffected controls was analyzed with the new assay and a conventional RBA.

Results: Among the 100 serum samples from patients with type 1 diabetes, the time-resolved fluorimetric assay identified 74 IA-2A-containing sera, whereas the RBA detected 80 IA-2A-positive samples. Five of the six samples positive in the RBA but not detected by the time-resolved fluorimetric assay were only weakly positive in the RBA. The performance time of the time-resolved fluorimetric assay was 2.5 h compared with 10–12 h required by the RBA.

Conclusions: The time-resolved fluorimetric assay provides a simple, nonradioactive analysis method for the detection of IA-2As with a specificity and a sensitivity comparable to the RBA method. This assay allows substantial reduction in performance time compared with the conventional RBA.




The following articles in journals at HighWire Press have cited this article:


Home page
 Diabetes CareHome page
P. D. Burbelo, H. Hirai, H. Leahy, A. Lernmark, S. A. Ivarsson, M. J. Iadarola, and A. Louis Notkins
A New Luminescence Assay for Autoantibodies to Mammalian Cell-Prepared Insulinoma-Associated Protein 2
Diabetes Care, September 1, 2008; 31(9): 1824 - 1826.
[Abstract] [Full Text] [PDF]

Home page
 Clin. Chem.Home page
M. Ankelo, A. Westerlund, K. Blomberg, M. Knip, J. Ilonen, and A. E. Hinkkanen
Time-Resolved Immunofluorometric Dual-Label Assay for Simultaneous Detection of Autoantibodies to GAD65 and IA-2 in Children with Type 1 Diabetes
Clin. Chem., March 1, 2007; 53(3): 472 - 479.
[Abstract] [Full Text] [PDF]

Home page
 Clin. Chem.Home page
X. Palomer, D. Mauricio, J. Rodriguez-Espinosa, E. Zapico, C. Mayoral, F. Gonzalez-Sastre, A. de Leiva, and F. Blanco-Vaca
Evaluation of Two Nonisotopic Immunoassays for Determination of Glutamic Acid Decarboxylase and Tyrosine Phosphatase Autoantibodies in Serum
Clin. Chem., August 1, 2004; 50(8): 1378 - 1382.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2003 by the American Association for Clinical Chemistry.