title: Immunoblotting on HEp-2 cells increases the detection of antitopoisomerase 1 antibodies in patients with systemic sclerosis.
abstract: In order to improve the detection of antitopoisomerase 1 antibodies in a cohort of 111 systemic sclerosis patients, we have performed immunoblots on protein extracts of HEp-2 cells. Using indirect immunofluorescence and ELISA, 27 patients (24.3%) had antitopoisomerase 1 antibodies, 32 (28.8%) had anticentromere antibodies, 31 (27.9%) had antinuclear antibodies with none of these two antibodies and 21 (18.9%) had no antinuclear antibody. IgG from 24/27 (88.9%) patients with antitopoisomerase 1 antibodies bound to 2 protein bands of 63 and 100 kDa identified as topoisomerase 1 by N-terminal sequencing. Antitopoisomerase 1 antibodies were detected in 9 (8.1%) patients who had no antitopoisomerase 1 antibody as determined by ELISA. Patients with antitopoisomerase 1 antibodies had an almost similar phenotype without distinction between ELISA or immunoblot approaches. Our results provide evidence for the use of a combination of ELISA and immunoblot approaches for the detection of antitopoisomerase 1 antibodies.
authors.affiliation: Paris-Descartes University, UPRES-EA 4058, site Cochin, Paris, France.
authors.forename: Mathieu C
authors.initials: MC
authors.lastname: Tamby
authors.forename: Amélie
authors.initials: A
authors.lastname: Servettaz
authors.forename: Philippe
authors.initials: P
authors.lastname: Guilpain
authors.forename: Nicolas
authors.initials: N
authors.lastname: Tamas
authors.forename: Alice
authors.initials: A
authors.lastname: Berezné
authors.forename: Frédéric
authors.initials: F
authors.lastname: Batteux
authors.forename: Joseph
authors.initials: J
authors.lastname: Reinbolt
authors.forename: Loïc
authors.initials: L
authors.lastname: Guillevin
authors.forename: Bernard
authors.initials: B
authors.lastname: Weill
authors.forename: Luc
authors.initials: L
authors.lastname: Mouthon
mesh_terms: D000328:Adult; D000974:Antibodies, Antinuclear / Q000097:blood / Q000276:immunology; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology; D001324:Autoantigens / Q000276:immunology; D002460:Cell Line; D002503:Centromere / Q000276:immunology; D004264:DNA Topoisomerases, Type I / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005455:Fluorescent Antibody Technique; D006801:Humans; D015151:Immunoblotting / Q000379:methods; D007074:Immunoglobulin G / Q000097:blood* / Q000276:immunology; D008875:Middle Aged; D012595:Scleroderma, Systemic / Q000097:blood* / Q000276:immunology; D012680:Sensitivity and Specificity
chemical_list: D000974:Antibodies, Antinuclear; D001323:Autoantibodies; D001324:Autoantigens; D007074:Immunoglobulin G; D004264:DNA Topoisomerases, Type I