Evaluating Anti-SmD1-amino-acid 83-119 Peptide Reactivity in Children with Systemic Lupus Erythematosus and Other Immunological Diseases / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>SmD1-amino-acid 83-119 peptide (SmD183-119) is the major epitope of Smith (Sm) antigen, which is specific for adult systemic lupus erythematosus (SLE). The anti-SmD183-119 antibody has exhibited higher sensitivity and specificity than anti-Sm antibody in diagnosing adult SLE. However, the utility of anti-SmD183-119antibodies remains unclear in children with SLE (cSLE). This study aimed to assess the characteristics of anti-SmD183-119antibody in the diagnosis of cSLE.</p><p><b>METHODS</b>Samples from 242 children with different rheumatological and immunological disorders, including autoimmune diseases (SLE [n = 46] and ankylosing spondylitis [AS, n = 11]), nonautoimmune diseases (Henoch-Schonlein purpura [HSP, n = 60], idiopathic thrombocytopenia purpura [n = 27], hematuria [n = 59], and arthralgia [n = 39]) were collected from Shanghai Children's Medical Center from March 6, 2012 to February 27, 2014. Seventy age- and sex-matched patients were enrolled in this study as the negative controls. All the patients' sera were analyzed for the anti-SmD183-119, anti-Sm, anti-U1-nRNP, anti-double-stranded DNA (dsDNA), anti-nucleosome, anti-SSA/Ro60, anti-SSA/Ro52, anti-SSB, anti-Scl-70, and anti-histone antibodies using the immunoblotting assay. The differences in sensitivity and specificity between anti-SmD183-119 and anti-Sm antibodies were compared by Chi-square test. The correlations between anti-SmD183-119and other auto-antibodies were analyzed using the Spearman's correlation analysis. A value of P< 0.05 was considered statistically significant.</p><p><b>RESULTS</b>Thirty-six out of 46 patients with cSLE were found to be positive for anti-SmD183-119, while 12 patients from the cSLE cohort were found to be positive for anti-Sm. Compared to cSLE, it has been shown that anti-SmD183-119 was only detected in 27.3% of patients with AS and 16.7% of patients with HSP. In comparison with anti-Sm, it has been demonstrated that anti-SmD183-119 had a higher sensitivity (78.3% vs. 26.1%, χ2 = 25.1, P< 0.05) and a lower specificity (90.8% vs. 100%, χ2 = 13.6, P< 0.05) in the diagnosis of cSLE. Further analysis revealed that anti-SmD183-119antibodies were positively correlated with anti-dsDNA, anti-nucleosome, and anti-histone antibodies in cSLE. Moreover, it has been clearly shown that anti-SmD183-119 was more sensitive than anti-Sm in discriminating autoimmune diseases from nonautoimmune disorders in patients with arthralgia or hematuria.</p><p><b>CONCLUSIONS</b>Measurement of anti-SmD183-119in patients with cSLE has a higher sensitivity and a marginally lower specificity than anti-Sm. It has been suggested that inclusion of anti-SmD183-119testing in the integrated laboratory diagnosis of cSLE may significantly improve the overall sensitivity in child populations.</p>

Effect of enhanced green fluorescent protein fusion on Ano1 physiological feature / 生理学报

The aim of the present study was to investigate whether the physiological features of Ano1 were affected by enhanced green fluorescent protein (EGFP) fusing at Ano1 C-terminal. The eukaryotic expression vectors of Ano1 and EGFP-Ano1 were constructed, and these plasmids were transfected into Fischer rat thyroid follicular epithelial (FRT) cells using liposome. The expression and location of Ano1 were examined by using inverted fluorescence microscope. The ability of Ano1 to transport iodide was detected by kinetics experiment of fluorescence quenching. The results showed that both Ano1 and EGFP-Ano1 were expressed on FRT cell membrane and could be activated by Ca(2+). There was no significant difference of the ability to transport iodide between Ano1 and EGFP-Ano1. These results suggest Ano1 and EGFP-Ano1 have similar physiological feature.