Ebrahimi-Rad Mina, Khatami Shohreh, Akhbari Hadi, Mahmoudzadeh-Niknam Hamid, Valadbeigi Shirin, Mahmoudi Mahdi, Jamshidi Alireza, Riazi-Rad Farhad, Saghiri Reza
Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran.
Department of Rheumatology, Birjand University of Medical Sciences, Iran.
Reumatologia. 2020;58(6):350-356. doi: 10.5114/reum.2020.101276. Epub 2020 Dec 23.
Rheumatoid arthritis (RA) is categorized as an autoimmune disease with a frequency of 0.2-1% worldwide. It is reported that various autoantibodies are produced in the RA population, particularly against citrullinated peptides. Among various candidate markers for RA diagnosis, the citrullinated proteins have the highest specificity and sensitivity for both diagnosis and prognosis of RA. Anti-mutated citrullinated vimentin and α-enolase constitute a new class of autoantibodies for early detection of RA.
45 serum samples and 19 synovial fluid (SF) specimens collected from RA patients were considered for American College of Rheumatology criteria and 20 serum samples and 10 SF specimens were provided from healthy subjects as a control group. To assess the quantity of anti-citrullinated protein antibodies (ACPA), anti-mutated citrullinated vimentin (MCV) and anti-α-enolase in the serum and SF of RA patients were determined by the enzyme-linked immunosorbent assay (ELISA) method. For the evaluation of disease activity and joint destruction, we used the Disease Activity Score of 28 joints based on erythrocyte sedimentation rate (ESR) Disease Activity Score 28 (DAS28). Furthermore, to measure the molecular weight of vimentin and α-enolase, electrophoresis on 10% SDS-PAGE was performed as described before.
The anti-α-enolase level among serum samples from RA patients was significantly higher than in healthy subjects (4.49 ±0.20 ng/ml vs. 0.76 ±0.12 ng/ml) ( < 0.001). There was a direct relation between α-enolase quantity and (rheumatoid factor) RF and C-reactive protein (CRP) levels. The mean ESR value in positive and negative ACPA patients was 38.2 ±22.6 mm/h and 9.2 ±5.8 mm/h respectively ( < 0.0001). The mean DAS28-ESR was 3.3. The level of anti-MCV in the serum of RA patients (244.6 ±53.3 U/ml) was higher than in serum of the healthy group (148.73 ±71.8) ( < 0.0001). The level of anti-MCV in the SF of patients was 687.5 ±148.4 U/ml.
In conclusion, both autoantibodies against MCV and α-enolase are two important markers that increase in serum and SF of RA patients and are specific for diagnosis of RA disease.
类风湿性关节炎（RA）是一种自身免疫性疾病，在全球范围内的发病率为0.2 - 1%。据报道，RA患者体内会产生多种自身抗体，尤其是针对瓜氨酸化肽段的抗体。在各种RA诊断候选标志物中，瓜氨酸化蛋白对RA的诊断和预后具有最高的特异性和敏感性。抗突变瓜氨酸化波形蛋白和α - 烯醇化酶构成了用于RA早期检测的一类新型自身抗体。
收集45份来自RA患者的血清样本和19份滑膜液（SF）标本，依据美国风湿病学会标准进行分析，同时提供20份血清样本和10份SF标本作为健康对照组。为评估抗瓜氨酸化蛋白抗体（ACPA）的量，采用酶联免疫吸附测定（ELISA）法测定RA患者血清和SF中抗突变瓜氨酸化波形蛋白（MCV）和抗α - 烯醇化酶的含量。为评估疾病活动度和关节破坏情况，我们使用基于红细胞沉降率（ESR）的28个关节疾病活动评分（DAS28）。此外，按照之前所述方法，在10%十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳（SDS - PAGE）上进行波形蛋白和α - 烯醇化酶分子量的测定。
RA患者血清样本中的抗α - 烯醇化酶水平显著高于健康受试者（4.49±0.20 ng/ml对0.76±0.12 ng/ml）（P < 0.001）。α - 烯醇化酶量与类风湿因子（RF）和C反应蛋白（CRP）水平之间存在直接关系。ACPA阳性和阴性患者的平均ESR值分别为38.2±22.6 mm/h和9.2±'5.8 mm/h（P < 0.0001）。平均DAS28 - ESR为3.3。RA患者血清中抗MCV水平（244.6±53.3 U/ml）高于健康组血清（148.73±71.8）（P < 0.0001）。患者SF中抗MCV水平为687.5±148.4 U/ml。
总之，抗MCV和抗α - 烯醇化酶这两种自身抗体均是RA患者血清和SF中含量增加且对RA疾病诊断具有特异性的重要标志物。
