Prevalence of anti-DFS70 antibodies in patients with and without systemic autoimmune rheumatic diseases.

Abstract

OBJECTIVES:

Autoantibodies to the dense fine speckled 70 (DFS70) antigen are common among antinuclear antibodies (ANA) positive healthy individuals (HI). We assessed the prevalence of anti-DFS70 antibodies in patients with and without ANA-associated rheumatic diseases (AARDs) by two methods: chemiluminescent immunoassay (CIA) and an indirect immunofluorescence (IIF) assay based on immunoadsorption for DFS70.

METHODS:

Fifty-one ANA-positive sera samples from patients with confirmed clinical diagnosis of AARD, 92 samples from HI and 85 samples submitted to a reference laboratory for routine ANA testing were evaluated for the presence of anti-DFS70 antibodies. The samples were evaluated by QUANTA Flash DFS70 CIA using BIO-FLASH instrument and by NOVA Lite selected HEp-2 kit on NOVA View - an automated IIF system. Sera with DFS positive pattern were pre-absorbed with highly purified human DFS70 antigen, and then tested again.

RESULTS:

Twenty-four samples (10.5%) tested by QUANTA Flash DFS70 CIA were positive for anti-DFS70 antibodies. The prevalence of monospecific anti-DFS70 antibodies was significantly higher in healthy subjects than in patients with AARDs (10.9% vs. 1.9%, p=0.02). The frequency of anti-DFS70 antibodies in samples submitted for routine ANA testing was 15.2%. A very good agreement was found between CIA and the DFS pattern identified by the automated HEp-2 IIF (kappa=0.97). In 80% of the samples obtained from patients without AARDs, immunoadsorption effectively inhibited the anti-DFS70 antibodies.

CONCLUSIONS:

The data confirm that mono-specific anti-DFS70 antibodies are a strong discriminator between ANA positive HI and AARD patients, and their evaluation should be included in ANA testing algorithms.

• Authors: Ora Shovman, Boris Gilburd, Chen Chayat, Howard Amital, Pnina Langevitz, Abdulla Watad, Adi Guy, Dolores Perez, Danielle Azoulay, Miri Blank, Yael Segal, Chelsea Bentow, Michael Mahler, Yehuda Shoenfeld
• Journal: Clinical and experimental rheumatology (Clin Exp Rheumatol) 2018 Jan-Feb Vol. 36 Issue 1 Pg. 121-126 ISSN: 0392-856X [Print] Italy
• PMID: 28770702 (Publication Type: Journal Article)

Chemical References

• Adaptor Proteins, Signal Transducing
• Antibodies, Antinuclear
• Biomarkers
• PSIP1 protein, human
• Transcription Factors

Topics

• Adaptor Proteins, Signal Transducing (immunology)
• Antibodies, Antinuclear (blood)
• Autoimmunity
• Biomarkers (blood)
• Case-Control Studies
• Fluorescent Antibody Technique, Indirect
• Humans
• Immunoassay
• Immunosorbent Techniques
• Luminescent Measurements
• Predictive Value of Tests
• Reproducibility of Results
• Rheumatic Diseases (blood, diagnosis, epidemiology, immunology)
• Seroepidemiologic Studies
• Transcription Factors (immunology)