Article Text

Download PDFPDF

Anti-Ro52 reactivity is an independent and additional serum marker in connective tissue disease
Free
  1. I Peene1,
  2. L Meheus2,
  3. S De Keyser2,
  4. R Humbel3,
  5. E M Veys1,
  6. F De Keyser1
  1. 1Department of Rheumatology, University Hospital Gent, Belgium
  2. 2Innogenetics, Gent, Belgium
  3. 3Centre Hospitalier Luxembourg, Luxembourg
  1. Correspondence to:
    Dr I Peene, Department of Rheumatology 0K12IB, University Hospital Gent, De Pintelaan 185, B-9000 Ghent, Belgium;
    filip.dekeyser{at}rug.ac.be

Abstract

Objective: To determine whether anti-Ro52 is an independent serum marker in connective tissue disease.

Methods: Over a two year period, 1727 consecutive antinuclear antibody (ANA) positive serum samples were analysed in parallel by double immunodiffusion with thymus/spleen nuclear extract and by line immunoassay with recombinant Ro52, recombinant La/SSB, and natural Ro60. Sera that were only reactive towards Ro52 were further analysed by a variety of additional anti-SSA/Ro detection methods and by specific anti-Ro52 and anti-Ro60 assays. Natural purified SSA/Ro was analysed by immunoblot and protein sequencing.

Results: Analysis of natural purified SSA/Ro (Immunovision, Springdale, AR) showed only Ro60 and no immunoreactive Ro52. Consequently, assays based on this substrate only identify sera with anti-Ro60 reactivity. Twenty serum samples showed anti-Ro52 without anti-Ro60 and anti-SSB/La on line immunoassay. By additional testing, 2/20 sera were found positive for anti-Ro60 reactivity. The remaining 18 sera were not identified by any of the classical anti-SSA/Ro assays and were considered to be reactive only with Ro52 and not with Ro60. This anti-Ro52 reactivity was confirmed by natural and recombinant Ro52 in 16/18 cases. 12/18 sera corresponded to connective tissue diseases.

Conclusion: Anti-Ro52 positive sera without any evidence of anti-Ro60 and anti-La/SSB reactivity can be considered as an independent group that is systematically missed by classical anti-SSA/Ro detection methods owing to a bias towards anti-Ro60 reactivity. The anti-Ro52 sera are precipitin negative, not retrieved by SSA/Ro enzyme linked immunosorbent assays (ELISAs) based on natural SSA/Ro, and show no specific ANA fluorescence staining pattern. These findings together with the clinical data indicate that anti-Ro52 should be considered as an additional and independent serum marker.

  • anti-Ro52
  • anti-SSA/Ro
  • connective tissue disease
  • ANA, antinuclear antibodies
  • DID, double immunodiffusion
  • ELISA, enzyme linked immunosorbent assay
  • HPLC, high performance liquid chromatography
  • mAb, monoclonal antibody
  • PAGE, polyacrylamide gel electrophoresis
  • PBS, phosphate buffered saline
  • SDS, sodium dodecyl sulphate
View Full Text

Statistics from Altmetric.com

Footnotes

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.