Sarić-Matutinović Marija, Diana Tanja, Nedeljković-Beleslin Biljana, Ćirić Jasmina, Žarković Miloš, Perović-Blagojević Iva, Kahaly George J, Ignjatović Svetlana
University of Belgrade, Faculty of Pharmacy, Belgrade.
Johannes Gutenberg University (JGU) Medical Center, Department of Medicine I, Molecular Thyroid Research Laboratory, Mainz, Germany.
J Med Biochem. 2022 Apr 8;41(2):211-220. doi: 10.5937/jomb0-34718.
Thyrotropin receptor autoantibodies (TSH-RAb) are indispensable biomarkers in the laboratory assessment of thyroid-associated orbitopathy (TAO). Clinical sensitivity of three different assays for TSH-R-Ab determination was evaluated in patients with TAO.
87 consecutive TAO patients were enrolled and their serum samples analyzed in parallel with three assays. An ECLIA competitive binding and a chemiluminescent bridge immunoassay were used to measure total and binding TSH-R-Ab concentration, while their functional activity was determined using a stimulatory TSH-R-Ab (TSAb) cellbased bioassay.
Compared to the two binding assays (ECLIA p<0.001, bridge p=0.003), the TSAb bioassay was more sensitive pertaining to the positive detection of TSH-R-Ab in TAO patients. No difference (p=0.057) was noted between the ECLIA and bridge assays regarding sensitivity rate. All patients with active and/or moderate-to-severe TAO tested positive in the TSAb bioassay (100% and 100%, respectively), while the positivity rates for bridge and ECLIA binding assays were 89.7% and 82.1% for active TAO, and 90.2% and 86.3% for severe TAO, respectively. Negative predictive values of the bioassay, bridge, and ECLIA assays were 100%, 75%, and 71%, respectively for active TAO, and 100%, 86%, and 71%, respectively for moderate-to-severe TAO. The superiority of the bioassay was most prominent in euthyroid (ET) TAO. Positivity rates of the TSAb bioassay, bridge and ECLIA binding assays were 89.6%, 75%, and 64.6%, respectively for inactive TAO; 86.1%, 69.4%, and 52.8%, respectively for mild TAO; 87.5%, 62.5%, and 12.5%, respectively for euthyroid TAO. The bridge assay correlated better with the ECLIA binding assay (r=0.893, p<0.001), compared to the bioassay (r=0.669, p<0.001).
In patients with TAO of various activity and severity, the TSAb bioassay demonstrates a superior clinical performance compared to both ECLIA and bridge binding assays.
促甲状腺素受体自身抗体（TSH-RAb）是甲状腺相关眼病（TAO）实验室评估中不可或缺的生物标志物。本研究评估了三种不同的TSH-R-Ab检测方法在TAO患者中的临床敏感性。
连续纳入87例TAO患者，并采用三种检测方法对其血清样本进行平行分析。采用电化学发光免疫分析（ECLIA）竞争结合法和化学发光桥联免疫分析法检测总TSH-R-Ab和结合型TSH-R-Ab浓度，同时采用基于刺激型TSH-R-Ab（TSAb）的细胞生物分析法测定其功能活性。
与两种结合法（ECLIA，p<0.001；桥联法，p=0.003）相比，TSAb生物分析法在TAO患者TSH-R-Ab阳性检测方面更敏感。ECLIA法和桥联法在灵敏度方面无差异（p=0.057）。所有活动期和/或中重度TAO患者的TSAb生物分析法检测均为阳性（分别为100%和100%），而活动期TAO患者桥联法和ECLIA结合法的阳性率分别为89.7%和82.1%，重度TAO患者分别为90.2%和86.3%。生物分析法、桥联法和ECLIA法对活动期TAO的阴性预测值分别为100%、75%和71%，对中重度TAO的阴性预测值分别为100%、86%和71%。生物分析法的优势在甲状腺功能正常（ET）的TAO患者中最为突出。非活动期TAO患者TSAb生物分析法、桥联法和ECLIA结合法的阳性率分别为89.6%、75%和64.6%；轻度TAO患者分别为86.1%、69.4%和52.8%；甲状腺功能正常的TAO患者分别为87.5%、62.5%和12.5%。与生物分析法（r=0.669，p<0.001）相比，桥联法与ECLIA结合法的相关性更好（r=0.893，p<0.001）。
在不同活动度和严重程度的TAO患者中，TSAb生物分析法的临床性能优于ECLIA法和桥联结合法。
