Demonstration of Two Molecular Variants of Carcinoembryonic Antigen by Concanavalin A Sepharose Affinity Chromatography

摘要: The carcinoembryonic antigen (CEA) active glycoproteins from perchloric acid extract of liver-metastasized primary colon tumor have been separated by concanavalin A Sepharose (Con Sepharose) chromatography. CEA activities Con chromatography were designated as loosely bound and tightly which, respectively, eluted on the column between 0.12 0.15 m 0.3 α -methylmannose in a linear gradient -methylmannose. Further purification these Sephadex G-200, Bio-Gels A-1.5m P-300 yielded two variants (B1 C2) with activity. Both purified preparations had similar immunochemical properties. Their A280/A260 ratios 1.30 1.56, respectively. (B1) immunological, chromatographic, electrophoretic properties to those 125I-CEA, whereas (C2) lower molecular weight (120,000 140,000). Further, specificity CEA's was established their reactions immunoelectrophoresis specific goat anti-CEA antiserum obtained other investigators. results indicate practical use affinity for separation characterization glycoprotein antigens.