Carcinoembryonic antigen-binding immunoglobulin isolated from normal human serum by affinity chromatography.
A human immunoglobulin that binds carcinoembryonic antigen (CEA) was isolated from four individual normal human sera by affinity chromatography with the use of a CEA-Sepharose solid adsorbent. The yield of isolated protein, termed human CEA-binding protein (HCBP), ranged from 1.8 to 10 microgram/ml serum. HCBP is a gamma-globulin of restricted electrophoretic heterogeneity as shown by immunoelectrophoresis. HCBP was shown to bind radioiodine-labeled CEA both by a radioimmune precipitation assay and by a radioimmunoelectrophoresis assay. This protein was of practical interest because of its potential usefulness as a carrier of radioactivity or therapeutic agents to a CEA-producing tumor for therapeutic or diagnostic purposes.
D000912:Antibodies, Neoplasm / Q000302:isolation & purification*; D002272:Carcinoembryonic Antigen / Q000276:immunology*; D002352:Carrier Proteins / Q000276:immunology / Q000302:isolation & purification; D002846:Chromatography, Affinity; D006801:Humans; D007136:Immunoglobulins / Q000302:isolation & purification*; D009369:Neoplasms / Q000175:diagnosis / Q000276:immunology
D000912:Antibodies, Neoplasm; D002272:Carcinoembryonic Antigen; D002352:Carrier Proteins; D007136:Immunoglobulins