SPECIFICITY OF AUTOANTIBODIES FOR RECOMBINANT 60-KD AND 52-KD RO AUTOANTIGENS

Objective. To compare patterns of Ro autoantigen recognition in primar y Sjogren's syndrome (SS) and systemic lupus erythematosus (SLE). Meth ods. Sera were tested by enzyme-linked immunosorbent assay (ELISA) and immunoprecipitation for reactivity with recombinant human 60-kd and 5 2-kd Ro proteins. Results. SLE and primary SS sera exhibited similar p atterns of reactivity with the recombinant 52-kd protein. However, a g reater proportion of sera from primary SS patients than from SLE patie nts did not react with recombinant 60-kd protein in ELISA yet precipit ated its translation product in solution-Phase assays. Conclusion. Dis ease state can influence recognition of the recombinant 60-kd Ro antig en.