一种识别人类甲状腺球蛋白隐蔽表位的甲状腺癌特异性单克隆抗体。

A thyroid cancer specific monoclonal antibody which recognizes cryptic epitope(s) of human thyroglobulin.

作者信息

Sugawa H, Smith E, Imura H, Mori T

机构信息

Department of Laboratory Medicine, Kyoto University School of Medicine, Japan.

出版信息

Mol Cell Endocrinol. 1993 Jun;93(2):207-11. doi: 10.1016/0303-7207(93)90125-4.

DOI:10.1016/0303-7207(93)90125-4

PMID:7688705

Abstract

A monoclonal antibody (TCM-9) specific for human thyroid cancer but not for Graves' disease, adenoma or normal thyroid tissue was shown to recognize a 300 K protein but not to bind to native or mature human thyroglobulin (Tg). In this study, we investigated further the antigen recognized by TCM-9. When purified Tg was treated with periodate, dithiothreitol (DTT) and sodium dodecyl sulfate (SDS), immunoblotting of treated Tg with TCM-9 revealed an apparent enhancement of the staining only with DTT-treated Tg. Furthermore, the DTT-treated Tg was shown to bind dose-dependently to plates coated with TCM-9. We performed SDS-PAGE and immunoblot analyses on the immune complex obtained from a homogenate of thyroid cancer tissue which was preincubated with an excess of anti-Tg monoclonal antibody. When the protein was autoradiographed with [125I]TCM-9, a definite band was observed. The results indicate that TCM-9 is likely to be directed against a masked epitope of thyroglobulin which can be exposed after treatment with a reducing agent.

摘要

一种对人甲状腺癌具有特异性、但对格雷夫斯病、腺瘤或正常甲状腺组织无特异性的单克隆抗体（TCM-9），被证明可识别一种300K的蛋白质，但不与天然或成熟的人甲状腺球蛋白（Tg）结合。在本研究中，我们进一步研究了TCM-9所识别的抗原。当用高碘酸盐、二硫苏糖醇（DTT）和十二烷基硫酸钠（SDS）处理纯化的Tg时，用TCM-9对处理后的Tg进行免疫印迹分析，结果显示仅DTT处理的Tg染色明显增强。此外，DTT处理的Tg显示出与包被有TCM-9的平板呈剂量依赖性结合。我们对用过量抗Tg单克隆抗体预孵育的甲状腺癌组织匀浆获得的免疫复合物进行了SDS-PAGE和免疫印迹分析。当用[125I]TCM-9对该蛋白质进行放射自显影时，观察到一条明确的条带。结果表明，TCM-9可能针对甲状腺球蛋白的一个隐蔽表位，该表位在用还原剂处理后可暴露出来。