Molecular Thyroid Research Laboratory, Department of Medicine I, Johannes Gutenberg University Medical Center, Mainz, Germany.
Am J Clin Pathol. 2013 Feb;139(2):192-200. doi: 10.1309/AJCPZUT7CNUEU7OP.
The analytical performance and the clinical utility of a thyrotropin receptor (TSHR)-stimulating immunoglobulin (TSI) bioassay were compared with those of a TSHR-binding inhibitory immunoglobulin (TBII) assay. Limits of detection (LoD) and quantitation (LoQ), assay cutoff, and the half-maximal effective concentration (EC(50)) were measured. Dilution analysis was performed in sera of hyperthyroid patients with Graves disease (GD) during antithyroid treatment (ATD). Titer was defined as the first dilution step at which measurement of TSI or TBII fell below the assay cutoff. The LoD, LoQ, cutoff, and EC(50) of the bioassay were 251-, 298-, 814-, and 827-fold lower than for the TBII assay. There were 22%, 42%, 23%, and 14% more positive samples in the TSI bioassay at dilutions of 1:3, 1:9, 1:27, and 1:81 (P < .0001), respectively. Responders to ATD demonstrated marked differences in titers compared with nonresponders. The bioassay detected lower levels of TSHR autoantibodies, and the dilution analysis provided similar predictive values of both assays in GD.
比较了促甲状腺激素受体（TSHR）刺激免疫球蛋白（TSI）生物测定和 TSHR 结合抑制免疫球蛋白（TBII）测定的分析性能和临床实用性。测量了检测限（LoD）和定量限（LoQ）、测定截止值和半最大有效浓度（EC（50））。在抗甲状腺治疗（ATD）期间患有格雷夫斯病（GD）的甲状腺功能亢进患者的血清中进行了稀释分析。滴度定义为测量 TSI 或 TBII 低于测定截止值的第一个稀释步骤。生物测定的 LoD、LoQ、截止值和 EC（50）分别比 TBII 测定低 251、298、814 和 827 倍。在 1:3、1:9、1:27 和 1:81 的稀释度下，TSI 生物测定的阳性样本分别增加了 22%、42%、23%和 14%（P <.0001）。对 ATD 有反应的患者与无反应的患者相比，滴度有明显差异。生物测定检测到较低水平的 TSHR 自身抗体，并且稀释分析在 GD 中提供了两种测定的相似预测值。
