Clinical and serological associations of anti-ribosomal P0 protein antibodies in systemic lupus erythematosus

The purpose of this study is to investigate the clinical and serological associations of anti-ribosomal P0 protein antibodies (anti-Rib-P0) in patients with systemic lupus erythematosus (SLE). The sera of 470 patients with SLE and 124 patients with primary Sjogren's Syndrome (pSS) were collected. Line immunoassay (LIA) was used to detect anti-Rib-P0 and other related antibodies. A complete laboratory evaluation and clinical examination were also performed in each SLE patient. The prevalence of anti-Rib-P0 in SLE patients was significantly higher than that in pSS patients (35.74 vs 6.45%) (P < 0.001). There was a significantly lower prevalence of cardiac involvement in anti-Rib-P0-positive SLE patients compared to anti-Rib-P0-negative SLE patients (P = 0.019); no significant associations of anti-Rib-P0 antibodies with encephalopathy manifestations and other vital organs involvement were observed. Anti-nucleosomes, anti-dsDNA, anti-Histones, anti-SmD1, and anti-U1snRNP were significantly associated with serum anti-Rib-P0 antibodies positivity in SLE patients (all P < 0.05). The sensitivity and specificity of the anti-Rib-P0 antibodies to diagnose SLE were 35.74 and 93.55%, respectively. There is a higher prevalence of anti-Rib-P0 in SLE patients. Anti-Rib-P0 positivity may indicate lower cardiac involvement for SLE patients. It may serve as an important complementary parameter in SLE, in addition to anti-dsDNA, anti-SmD1, and anti-nucleosomes.