title: Carcinoembryonic antigen (CEA) of human tissue extracts: partial characterization of two variants separated by affinity chromatography on concanavalin A.
abstract: The carcinoembryonic antigen (CEA) of normal and pathological tissue extracts was separated into two variants, Concanavalin A reactive (CEAr) and non-reactive CEA (CEAn) by affinity chromatography on Con A Sepharose columns. CEAr was the quantitatively predominant variant. CEAn varied in concentration between 0.2 and 6 percent of the total CEA activity. The affinity of CEAn for anti-CEA antibodies was significantly lower than that of CEAr. Pooled extracts of primary adenocarcinomas of the colon contained CEAn in the lowest concentration and with the least affinity for antibodies. It is suggested that a deficiency and/or steric blocking of alpha-D-mannopyranosyl residues in CEAn reduce the affinities for both antibodies and Con A.
mesh_terms: D000230:Adenocarcinoma / Q000032:analysis; D002272:Carcinoembryonic Antigen / Q000302:isolation & purification; D002846:Chromatography, Affinity; D003110:Colonic Neoplasms / Q000032:analysis; D003208:Concanavalin A; D005333:Fetus; D014644:Genetic Variation; D006801:Humans; D008099:Liver / Q000032:analysis; D008103:Liver Cirrhosis / Q000378:metabolism; D008113:Liver Neoplasms / Q000032:analysis; D008168:Lung / Q000032:analysis; D009362:Neoplasm Metastasis; D009928:Organ Specificity; D011863:Radioimmunoassay; D013154:Spleen / Q000032:analysis
chemical_list: D002272:Carcinoembryonic Antigen; D003208:Concanavalin A