Application of Ig genes encoding anti-TSH receptor autoantobodies.

编码抗TSH受体自身抗体的Ig基因的应用。

基本信息

批准号：
08671150
负责人：
AKAMIZU Takashi
金额：
$ 1.41万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08671150/
关键词：
Graves'disease,TSH receptor,Ig genes autoantibody,autoimmune thyroid disease

项目摘要

Anti-thyrotropin (TSH) receptor autoantibodies (TSHRAbs) are known to be involved in Geaves' disease. To elucidate the molecular mechanism of the pathogenesis of Graves' disease, we previously isolated and reconstituted the immunoglobulin genes of two B cell clones prcducing a monoclonal thyroid stimulating antibody (TSAb), a stimulating type of TSHRAb, obtainedfrom patients with Graves' disease. In the present study, we produced a large amount of recombinant monoclonal TSAbs in eukariotic cells using these genes and applied them to severral further investigations. First, we tried to identify their epitopes in the TSHR by using a panel of mutants of the extracellular domain of TSHR.Both antibodies abrogated or reduced TSAb activities in mutants of the N-terminal but not C-terminal region of the extracellular domain of TSHR,while TSH had opposite effect. Secondly, purified antibodies were radiolabeled and tested for binding to cells expressing high levels of TSHR.Although their affinities were lower than that of TSH,their bindings were not displaced by TSH.The antibody bindings were not mutually competitive, either. The finding indicates that these antibodies interact with the multiple conformational arrays of receptor determinants in the N-terminus and transduce a signal through binding sites different from TSH.

已知抗硫代蛋白（TSH）受体自身抗体（TSHRAB）参与Geaves疾病。为了阐明Graves疾病发病机理的分子机制，我们先前隔离并重构了两个B细胞克隆的免疫球蛋白基因，这些基因促进了单克隆甲型甲状腺刺激抗体（TSAB）（TSAB），一种刺激性的TSHRAB，刺激性的TSHRAB患者患有Graves患者患有Graves疾病。在本研究中，我们使用这些基因在真核细胞中产生了大量的重组单克隆TSAB，并将其应用于Supterral进一步研究。首先，我们试图通过使用TSHR的细胞外结构域的突变体来鉴定其在TSHR中的表位。任何抗体在N末端的突变体中废除或减少了TSHR的C末端区域的TSAB活性，而TSHR的细胞外域的C末端区域则相反。其次，对纯化的抗体进行放射标记并测试与表达高水平TSHR的细胞的结合。尽管它们的亲和力低于TSH的亲和力，但它们的结合也不被TSH置换。抗体结合也不相互竞争。该发现表明，这些抗体与N末端中受体决定因素的多构象阵列相互作用，并通过与TSH不同的结合位点传递信号。