Evaluation of a 1 step TRAb Assay for the Detection of High-affinity Components to hTSHR: Evidences Indicating Superiority of the Assay in the Lower TRAb Range

Endocrine Journal

Toru MORI¹  Toshio IWAKURA²  Cyeol SON²  Kaori IKEDA²  Takashi ISHIHARA²  Katsuji IKEKUBO³  Megumu HINO³  Hiromasa KOBAYASHI²  Yasuhiko SAIKI³ 

[1] Department of Internal Medicine, Kyoto Higashiyama Takeda Hospital;Department of Internal Medicine, Kobe City General Hospital;Department of Nuclear Medicine, Kobe City General Hospital

关键词: TRAb;    TBII;    TSHR;    Graves' disease;    Competitive binding assay;   

DOI  :  10.1507/endocrj.53.147

学科分类：内分泌与代谢学

来源: Japan Endocrine Society

【 摘 要 】

References(34)Cited-By(1)The aim of this study was to develop an assay to selectively detect high-affinity components among TRAb. Using an rhTSHR-coated tube system, a 1 step TRAb assay method was developed that included 1) co-incubation with 125I-bTSH, 2) a 50 μl serum sample, 3) an increased incubation volume (450 μl), and 4) a 1 hour incubation time. Sixty-one TRAb positive Graves' sera were studied. When the regular TRAb assay (Reg) results were quantitatively compared to the 1 step assay (1 step) results, certain dispersions and overestimations using the latter were seen. Further, some 1 step positive results were observed in the low Reg range. Overestimations were considered mostly due to the differences between TRAb standard and patients' serum TRAb in the binding competition against co-incubated 125I-bTSH, which was shown from a modified assay mimicking the 1 step conditions. Therefore, the 1 step results were decided to be expressed by % inhibition against 125I-bTSH. As for data dispersions, TRAb absorptions during the regular 1st incubation were studied. Individually, the absorption rates varied from 11 to 69%, and higher absorptions were observed in lower Reg range, especially in those negative by the 1 step. Observed 1 step positive results in the low Reg range were of interest, and 1 step/Reg ratios were calculated. The ratios with 1 step negative samples were significantly lower than those of 1 step positive samples. In conclusion, the 1 step assay was proved to detect a particular and biologically active TRAb, especially in those with low TRAb. The clinical significance of the 1 step results should be of future interest.

【 授权许可】

Unknown