Division of Rheumatology, University of Padova, Via Giustiniani 2, Padua, Italy.
Ann Rheum Dis. 2010 Sep;69(9):1704-10. doi: 10.1136/ard.2009.117804. Epub 2010 May 3.
To evaluate the prevalence and correlates of anti-pentraxin 3 (PTX3) antibodies in systemic lupus erythematosus (SLE).
Serum samples from 130 patients with SLE, 130 age- and sex-matched healthy subjects and 130 patients with other autoimmune rheumatic diseases (oARD) were analysed by home-made ELISAs using as substrate human recombinant PTX3 and two peptides, PTX3_1 and PTX3_2, obtained from the complete protein, identified as potential antigenic sites using the Lasergene DNA program (DNA Star). Inhibition tests were performed to evaluate potential interferences between bovine serum albumin or C-reactive protein and anti-PTX3 or anti-PTX3 peptides, and between antigens and antibodies. Statistical analysis was performed using receiving operating characteristics curves, the Fisher exact test, two-tailed t test and Pearson correlations.
Patients with SLE had higher levels and prevalence of anti-PTX3, anti-PTX3_1 and anti-PTX3_2 antibodies than patients with oARD or healthy controls (p<0.001 for all). No differences were observed between patients with oARD and healthy controls. A correlation was found between anti-PTX3 and anti-PTX3_2 antibodies (r=0.615, p<0.001). No association was observed between these antibodies and disease activity. Univariate and multivariate analyses showed that anti-PTX3 and anti-PTX3_2 antibody levels and prevalence were higher in patients without glomerulonephritis and in patients positive for antiphospholipid antibody. All inhibition tests were negative apart from PTX3 against anti-PTX3 antibody or, to a lesser extent, against anti-PTX3_2 antibody, and PTX3_2 against anti-PTX3_2 antibody, all in a dose-dependent manner.
Anti-PTX3 antibodies are significantly prevalent in patients with SLE where they might provide protection from renal involvement. The antigenic properties of PTX3_2 peptide are similar to those of PTX3, suggesting its potential use in further analyses.
评估抗 pentraxin 3（PTX3）抗体在系统性红斑狼疮（SLE）中的流行率和相关性。
使用自制 ELISA 分析了 130 例 SLE 患者、130 名年龄和性别匹配的健康对照者和 130 例其他自身免疫性风湿病（oARD）患者的血清样本，该 ELISA 使用人重组 PTX3 和两个肽段（PTX3_1 和 PTX3_2）作为底物，这两个肽段是使用 Lasergene DNA 程序（DNA Star）从完整蛋白中鉴定出的潜在抗原性位点。进行抑制试验以评估牛血清白蛋白或 C 反应蛋白与抗-PTX3 或抗-PTX3 肽之间以及抗原与抗体之间的潜在干扰。使用接收操作特征曲线、Fisher 确切检验、双尾 t 检验和 Pearson 相关性进行统计分析。
SLE 患者的抗-PTX3、抗-PTX3_1 和抗-PTX3_2 抗体水平和患病率均高于 oARD 患者或健康对照者（p<0.001）。oARD 患者和健康对照者之间未观察到差异。抗-PTX3 与抗-PTX3_2 抗体之间存在相关性（r=0.615，p<0.001）。这些抗体与疾病活动度之间无相关性。单变量和多变量分析显示，无肾炎和抗磷脂抗体阳性的患者的抗-PTX3 和抗-PTX3_2 抗体水平和患病率更高。除了 PTX3 对抗-PTX3 抗体或在较小程度上对抗-PTX3_2 抗体以及 PTX3_2 对抗-PTX3_2 抗体的抑制试验呈阳性外，所有抑制试验均为阴性，且均呈剂量依赖性。
抗-PTX3 抗体在 SLE 患者中明显流行，它们可能为肾脏受累提供保护。PTX3_2 肽的抗原性与 PTX3 相似，提示其在进一步分析中的潜在用途。
