Shovman Ora, Gilburd Boris, Chayat Chen, Amital Howard, Langevitz Pnina, Watad Abdulla, Guy Adi, Perez Dolores, Azoulay Danielle, Blank Miri, Segal Yael, Bentow Chelsea, Mahler Michael, Shoenfeld Yehuda
Zabludowitz Centre for Autoimmune Diseases; Department of Internal Medicine 'B'; Rheumatology Unit, Sheba Medical Centre, Tel Hashomer, Israel.
Zabludowitz Centre for Autoimmune Diseases, Sheba Medical Centre, Tel Hashomer, Israel.
Clin Exp Rheumatol. 2018 Jan-Feb;36(1):121-126. Epub 2017 Jul 27.
Autoantibodies to the dense fine speckled 70 (DFS70) antigen are common among antinuclear antibodies (ANA) positive healthy individuals (HI). We assessed the prevalence of anti-DFS70 antibodies in patients with and without ANA-associated rheumatic diseases (AARDs) by two methods: chemiluminescent immunoassay (CIA) and an indirect immunofluorescence (IIF) assay based on immunoadsorption for DFS70.
Fifty-one ANA-positive sera samples from patients with confirmed clinical diagnosis of AARD, 92 samples from HI and 85 samples submitted to a reference laboratory for routine ANA testing were evaluated for the presence of anti-DFS70 antibodies. The samples were evaluated by QUANTA Flash DFS70 CIA using BIO-FLASH instrument and by NOVA Lite selected HEp-2 kit on NOVA View - an automated IIF system. Sera with DFS positive pattern were pre-absorbed with highly purified human DFS70 antigen, and then tested again.
Twenty-four samples (10.5%) tested by QUANTA Flash DFS70 CIA were positive for anti-DFS70 antibodies. The prevalence of monospecific anti-DFS70 antibodies was significantly higher in healthy subjects than in patients with AARDs (10.9% vs. 1.9%, p=0.02). The frequency of anti-DFS70 antibodies in samples submitted for routine ANA testing was 15.2%. A very good agreement was found between CIA and the DFS pattern identified by the automated HEp-2 IIF (kappa=0.97). In 80% of the samples obtained from patients without AARDs, immunoadsorption effectively inhibited the anti-DFS70 antibodies.
The data confirm that mono-specific anti-DFS70 antibodies are a strong discriminator between ANA positive HI and AARD patients, and their evaluation should be included in ANA testing algorithms.
抗致密细斑点70（DFS70）抗原自身抗体在抗核抗体（ANA）阳性的健康个体（HI）中很常见。我们通过两种方法评估了有无ANA相关风湿性疾病（AARD）患者中抗DFS70抗体的患病率：化学发光免疫分析（CIA）和基于DFS70免疫吸附的间接免疫荧光（IIF）分析。
对51份确诊为AARD的患者的ANA阳性血清样本、92份HI的样本以及85份提交至参考实验室进行常规ANA检测的样本进行抗DFS70抗体检测。使用BIO-FLASH仪器通过QUANTA Flash DFS70 CIA对样本进行评估，并在NOVA View（一种自动化IIF系统）上使用NOVA Lite精选的HEp-2试剂盒进行评估。对DFS呈阳性模式的血清用高度纯化的人DFS70抗原进行预吸附，然后再次检测。
通过QUANTA Flash DFS70 CIA检测的24份样本（10.5%）抗DFS70抗体呈阳性。健康受试者中单一特异性抗DFS70抗体的患病率显著高于AARD患者（10.9%对1.9%，p = 0.02）。提交进行常规ANA检测的样本中抗DFS70抗体的频率为15.2%。发现CIA与自动化HEp-2 IIF鉴定的DFS模式之间具有非常好的一致性（kappa = 0.97）。在80%从无AARD患者获得的样本中，免疫吸附有效抑制了抗DFS70抗体。
数据证实单一特异性抗DFS70抗体是ANA阳性HI和AARD患者之间的有力鉴别指标，其评估应纳入ANA检测算法中。
