Heterogeneity of the anti-Ro(SSA) response in rheumatic diseases

J Rheumatol. 1994 Aug;21(8):1450-6.


Objective: The immune response to the Ro(SSA) antigen is heterogeneous. Anti-Ro(SSA) positive sera may contain antibodies recognizing either a 60 or a 52 kDa polypeptide component of the Ro(SSA) particle. Thus we sought to determine the profile of anti-Ro(SSA) antibodies defined by immunoblotting in patients with rheumatic diseases.

Methods: Immunoblotting against human placenta extract and ELISA against recombinant Ro(SSA) antigen as confirmatory tests were done to detect anti-Ro(SSA) antibodies in 563 sera from patients with systemic lupus erythematosus (SLE). Sjögren's syndrome (SS), rheumatoid arthritis (RA) and other connective tissue diseases.

Results: Anti-52 kDa antibodies were more common in primary patients with SS (9/22; 40.9%) than in patients with SLE (29/135; 21.4%) or patients with RA (7/315; 2.2%). Anti-60 kDa antibodies were more frequent in patients with SLE (26/135; 19.2%) than in patients with primary SS (2/22; 9%) or RA (17/315; 5.3%). None of the 22 patients with primary SS had only antibodies to the 60 kDa polypeptide. Among the 153 patients whose sera were positive by ELISA, 73 (47.7%) were negative by immunoblotting. The most frequent diagnoses in these sera were RA and SLE. The anti-52 kDa sera had higher optical density values compared to anti-60 kDa sera.

Conclusions: Our observations indicate the existence of qualitatively and quantitatively different anti-Ro(SSA) responses in the rheumatic diseases. The major responses are anti-52 kDa antibodies in primary SS, both anti-52 and anti-60 kDa antibodies in SLE, and anti-60 kDa antibodies in RA and other connective tissue diseases.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Antinuclear / blood*
  • Antibodies, Antinuclear / immunology
  • Case-Control Studies
  • Connective Tissue Diseases / immunology
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunoblotting
  • Rheumatic Diseases / immunology*


  • Antibodies, Antinuclear
  • SS-A antibodies