Diagnostic Accuracy of Methods for Detection of Antibodies against Type I Interferons in Patients with Endocrine Disorders

Abstract

Autoantibodies against type 1 interferons (IFN-I) are a highly specific marker for type 1 autoimmune polyglandular syndrome (APS-1). Moreover, determination of antibodies to omega-interferon (IFN-ω) and alpha2-interferon (IFN-α2) allows a short-term diagnosis in patients with isolated and atypical forms of APS-1. In this study, a comparison of three different methods, namely multiplex microarray-based, cell-based and enzyme-linked immunosorbent assays for detection of antibodies against omega-interferon and alpha2-interferon, was carried out. A total of 206 serum samples from adult patients with APS-1, APS-2, isolated autoimmune endocrine pathologies or non-autoimmune endocrine disorders, and healthy individuals were analyzed. In the APS-1 patient cohort (n = 18), there was good agreement between the results of anti-IFN-I antibody tests performed by three methods, with 100% specificity and sensitivity for microarray-based assay. Although only the cell-based assay can determine the neutralizing activity of autoantibodies, the microarray-based assay can serve as a highly specific and sensitive screening test to identify anti-IFN-I antibody positive patients.

Keywords: ELISA; autoantibodies; cell-based autoantibody assay; interferon-α2; interferon-ω; multiplex assay; protein microarray; type I interferon.

Figure 1

Fluorescence images of microarrays after assay with serum samples from: an APS-1 patient (a), a patient with multiple endocrine neoplasia type 1 (b). Groups of elements with immobilized omega-interferon (IFN-ω) and alpha2a-interferon (IFN-α-2a) are indicated by solid lines.