Assessment of autoantibodies to interferon-ω in patients with autoimmune polyendocrine syndrome type 1: using a new immunoprecipitation assay.
Clin Chem Lab Med 2017;
55:1003-1012. [PMID:
28099118 DOI:
10.1515/cclm-2016-0615]
[Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 11/22/2016] [Indexed: 01/17/2023]
Abstract
BACKGROUND
Measurements of autoantibodies to interferon-ω (IFN-ω) in patients with autoimmune polyglandular syndrome type 1 (APS-1) were performed using a new immunoprecipitation assay (IPA) based on 125I-labeled IFN-ω.
METHODS
We have developed and validated a new IPA based on 125I-labeled IFN-ω. Sera from 78 patients (aged 3-78 years) with clinically diagnosed APS-1, 35 first degree relatives, 323 patients with other adrenal or non-adrenal autoimmune diseases and 84 healthy blood donors were used in the study. In addition, clinical features and autoimmune regulator (AIRE) genotype for the APS-1 patients were analyzed.
RESULTS
Sixty-six (84.6%) of 78 APS-1 patients were positive for IFN-ω Ab using 125I-labeled IFN-ω IPA. IFN-ω Ab was the most prevalent of the six different autoantibodies tested in this group of APS-1 patients. All 66 IFN-ω Ab-positive APS-1 patients had AIRE mutations and 7 IFN-ω Ab-negative patients had no detectable AIRE mutations, whereas 3 (3.8%) patients were discrepant for IFN-ω Ab positivity and AIRE mutation results. Out of autoimmune controls studied, two patients were positive for IFN-ω Ab. Positivity and levels of IFN-ω Ab in the APS-1 patients studied were similar irrespective of patient's clinical phenotype and AIRE genotype. Furthermore, IFN-ω Ab levels did not change over time (up to 36 years of disease duration) in 8 APS-1 patients studied.
CONCLUSIONS
We have developed a novel, highly sensitive and specific assay for measurement of IFN-ω Ab. It provides a simple and convenient method for the assessment of patients with APS-1 and selecting patients suspected of having APS-1 for AIRE gene analysis.
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