Ochi Y, Fujiyama Y, Hosoda S, Hamazu M, Kajita Y, Myazaki T, Hachiya T, Ishida M
J Immunol Methods. 1982 Jul 30;52(2):213-21. doi: 10.1016/0022-1759(82)90047-3.
Purification of radiolabeled carcinoembryonic antigen (CEA) preparations by affinity chromatography with anti-AG bound to Sepharose was attempted, since an immunological similarity between AG (alpha 1-acid glycoprotein) and a portion of CEA had been noted. When 125I-CEA was purified in this manner, the fraction which did not bind to the column showed decreased reactivity with either anti-AG or anti-CEA. The retained fraction showed enhanced reactivity with both anti-AG and anti-CEA. The yield of purified CEA increased when the CEA preparation was allowed to react with the anti-AG column overnight. Purification of CEA from tumor tissue was performed by affinity chromatography. A perchloric acid (PCA) extract from cancer tissue was mixed with antiserum against CEA to give an immune complex, and a CEA-reactive fraction obtained by PCA extraction. The CEA-reactive fraction was eluted from a Sephadex G-200 column, and final purification was by anti-AG chromatography. When purified CEA was applied to a Sephadex G-200 column with carrier protein after labeling with 125I, the eluted radioactivity was found only in the 180,000 dalton fraction. Almost all the radioactivity was precipitated from the labeled protein by either anti-AG or anti-CEA. Purification of CEA is possible by affinity chromatography with anti-AG bound to Sepharose.
由于已注意到α1-酸性糖蛋白（AG）与癌胚抗原（CEA）的一部分存在免疫相似性，因此尝试通过将抗AG结合到琼脂糖凝胶上的亲和色谱法来纯化放射性标记的CEA制剂。当以这种方式纯化125I-CEA时，未与柱结合的部分与抗AG或抗CEA的反应性降低。保留部分与抗AG和抗CEA的反应性均增强。当CEA制剂与抗AG柱过夜反应时，纯化CEA的产量增加。通过亲和色谱法从肿瘤组织中纯化CEA。将癌组织的高氯酸（PCA）提取物与抗CEA抗血清混合以形成免疫复合物，并通过PCA提取获得CEA反应性部分。从葡聚糖凝胶G-200柱上洗脱CEA反应性部分，最后通过抗AG色谱法进行纯化。当用125I标记后的纯化CEA与载体蛋白一起应用于葡聚糖凝胶G-200柱时，洗脱的放射性仅出现在180,000道尔顿的部分。几乎所有的放射性都被抗AG或抗CEA从标记蛋白中沉淀出来。通过将抗AG结合到琼脂糖凝胶上的亲和色谱法可以纯化CEA。
