Anti-ribosomal P protein antibodies detected by immunoblotting in patients with connective tissue diseases: their specificity for SLE and association with IgG anticardiolipin antibodies

摘要: OBJECTIVE—To assess the prevalence and clinical serological associations of anti-ribosomal P protein antibodies (anti-P antibodies) in patients with connective tissue diseases (CTDs) investigate immunobiological nature autoantibody clustering which anti-P play a part. METHODS—IgG sera 267 patients CTDs 31 healthy subjects were analysed by immunoblotting performed on cytoplasmic extract Raji cells. 60 patients systemic lupus erythematosus (SLE), 32 systemic sclerosis, 46 primary Sjogren's syndrome, 16 poly/dermatomyositis, 11 rheumatoid arthritis, 8 undifferentiated CTD, 72 overlap 22 primary antiphospholipid syndrome studied. Anti-P affinity purified elution from nitrocellulose bound antigen tested ELISA for their binding activity to cardiolipin. RESULTS—Anti-P detected 16 (6%) none controls: 12/60 SLE (20%) 4/80 undifferentiated/overlap CTD (5%). A close association IgG proteins cardiolipin was seen (p=0.0009, odds ratio 18.33). 9 of 12 anti-P serum samples could be fractions cross reacted plate coated cardiolipin. CONCLUSIONS—Anti-P immunoreactivity is specific marker lupus-like disease its detection recommended as powerful diagnostic tool. are strongly clustered anticardiolipin sera, even if they independently elicited. This suggests that cognate autoantigens part common pathogenetic pathway SLE.