Anti-TIF-1γ Antibody Detection Using a Commercial Kit vs In-House Immunoblot: Usefulness in Clinical Practice.

Abstract

Objectives:

Anti-TIF-1γ autoantibody detection is important for cancer screening in patients with dermatomyositis. The gold standard for anti-TIF-1γ detection, immunoprecipitation, is only available from a few specialized laboratories worldwide, so commercial ELISA/immunoblot tests have emerged in recent years. To analyze their usefulness in diagnosing cancer-associated dermatomyositis, we compared Euroimmun Euroline profile with our previously validated in-house immunoblot assay with human recombinant TIF-1γ.

Methods:

We included 308 adult patients from Hospital de la Santa Creu I Sant Pau and Vall Hebrón Hospital (Barcelona, Spain) tested for anti-TIF-1γ autoantibodies using the Euroline profile and an in-house immunoblot assay.

Results:

A total of 27 anti-TIF-1γ were detected by the Euroline and 12 by the in-house assay. Fair agreement was observed between Euroline and the in-house immunoblot Cohen's kappa 0.3163. Expected prevalence of anti-TIF-1γ autoantibodies was observed for the two methods for dermatomyositis and undifferentiated connective tissue diseases, but unexpectedly high prevalence of anti-TIF-1γ autoantibodies was detected by Euroline compared to the in-house immunoblot for other diseases (16.5% Euroline vs 0.8% in-house immunoblot, p<0.01). The in-house IB compared to Euroline more reliably detected cancer in patients with DM with anti-TIF-1γ antibodies (p=0.0014 vs p=0.0502 for in-house immunoblot vs Euroline).

Conclusion:

We recommend using a second validated method to confirm Euroline-detected anti-TIF-1γ antibodies when the dermatomyositis diagnosis is not definitive. Furthermore, in the context of definite DM diagnosis with negative anti-TIF-1γ antibodies by Euroline and no other myositis specific antibody, is also recommendable to confirm by a second validated method.

• Authors: Anaís Mariscal, Milena Milán, Andrés Baucells, Maria Angeles Martínez, Andrea Garcia Guillen, Ernesto Trallero-Araguás, Marcelo Alvarado-Cardenas, Laura Martínez-Martínez, Leticia Alserawan, Teresa Franco-Leyva, María Teresa Sanz-Martínez, Laura Viñas-Giménez, Hector Corominas, Cándido Juárez, Iván Castellví, Albert Selva-O'Callaghan
• Journal: Frontiers in immunology (Front Immunol) Vol. 11 Pg. 625896 ( 2020) ISSN: 1664-3224 [Electronic] Switzerland
• PMID: 33613568 (Publication Type: Comparative Study, Journal Article)
• Copyright: Copyright © 2021 Mariscal, Milán, Baucells, Martínez, Guillen, Trallero-Araguás, Alvarado-Cardenas, Martínez-Martínez, Alserawan, Franco-Leyva, Sanz-Martínez, Viñas-Giménez, Corominas, Juárez, Castellví and Selva-O’Callaghan.

Chemical References

• Antibodies, Neoplasm
• Autoantibodies
• Neoplasm Proteins
• Reagent Kits, Diagnostic
• TRIM33 protein, human
• Transcription Factors

Topics

• Adult
• Antibodies, Neoplasm (blood, immunology)
• Autoantibodies (blood, immunology)
• Dermatomyositis (blood, immunology)
• Female
• Humans
• Immunoblotting
• Male
• Neoplasm Proteins (blood, immunology)
• Neoplasms (blood, immunology)
• Reagent Kits, Diagnostic
• Transcription Factors (blood, immunology)