ARTICOLO ORIGINALE   

La Rivista Italiana della Medicina di Laboratorio 2020 Giugno;16(2):94-100

DOI: 10.23736/S1825-859X.20.00058-4

Copyright © 2020 EDIZIONI MINERVA MEDICA

language: Italian

Understanding the biological significance of anti-DFS70 antibodies: impact of TNFα blockers on their occurrence in inflammatory arthritis

Teresa CARBONE ^{1, 2}, Carmela ESPOSITO ³, Vito PAFUNDI ² ✉, Antonio CARRIERO ¹, Maria C. PADULA ¹, Angela A. PADULA ¹, Salvatore D’ANGELO ^{1, 4}

¹ Istituto Reumatologico Lucano (IReL), Azienda Ospedaliera San Carlo, Potenza, Italia; ² Laboratorio di Immunopatologia, Azienda Ospedaliera San Carlo, Potenza, Italia; ³ Reumatologia - Dipartimento di Medicina Interna, Ospedale di Prato, Prato, Italia; ⁴ Fondazione Basilicata Ricerca Biomedica, Potenza, Italia

BACKGROUND: Anti-dense fine speckled 70 kD (DFS70) antibodies have been detected in patients with several chronic inflammatory conditions, cancer, rheumatic diseases and also in apparently healthy individuals. The impact of therapeutic intervention on the occurrence of these antibodies is still undefined. The aims of our study were firstly to investigate the prevalence of anti-DFS70 antibodies in a large cohort of inflammatory arthritis patients and then to elucidate the effects of anti-TNFalpha (TNFα therapies on their development.
METHODS: Sera from adult rheumatoid arthritis (RA) and spondyloarthritis (SpA) patients, fulfilling ACR/EULAR 2010 and ASAS 2011 criteria, respectively, were analyzed for anti-DFS70 antibodies as measured by indirect immunofluorescence (IIF) and by immunoblotting (IB). Medical history, demographic, clinical and laboratory data were collected at enrolment.
RESULTS: The prevalence rate of anti-DFS70 antibodies was 4.0% (4/100) in RA and 3.8% (4/105) in SpA, showing no statistical differences between these disease groups (P>0.05). The evaluation of anti-DFS70 antibody induction rate after biologics showed that 3 out of 4 anti-DFS70 antibodies both in RA and in SpA cohorts were induced by anti-TNFα therapy. In the SpA group, all anti-DFS70 positive patients had a PsA diagnosis. Neither RA nor SpA anti-DFS70 positive patients developed the drug-induced lupus erythematosus (DILE) syndrome during treatment with TNFα therapy.
CONCLUSIONS: Our data showed high prevalence of anti-DFS70 antibody positivity in RA and SpA cohort. Anti-DFS70 antibodies that developed after anti-TNFα therapy were not associated to clinical manifestation of DLE. This observation supports the hypothesis that these autoantibodies do not have pathogenetic role. Further studies including larger patient cohorts are needed to validate this assumption.

KEY WORDS: Antibodies, antinuclear; Anti-TNFalpha blockers; Autoimmunity; Arthritis, rheumatoid; Spondyloarthritis