Specificity of autoantibodies for recombinant 60–kd and 52–kd ro autoantigens

Abstract

Objective. To compare patterns of Ro autoantigen recognition in primary Sjögren's syndrome (SS) and systemic lupus erythematosus (SLE). Methods. Sera were tested by enzyme–linked immunosorbent assay (ELISA) and immunoprecipitation for reactivity with recombinant human 60–kd and 52–kd Ro proteins. Results. SLE and primary SS sera exhibited similar patterns of reactivity with the recombinant 52–kd protein. However, a greater proportion of sera from primary SS patients than from SLE patients did not react with recombinant 60–kd protein in ELISA yet precipitated its translation product in solution–phase assays. Conclusion. Disease state can influence recognition of the recombinant 60–kd Ro antigen.