title: Molecular heterogeneity of pregnancy specific beta 1 glycoprotein: the effect on measurement by radioimmunoassay and electroimmunoassay.
abstract: A comparison of methods for the quantification of circulating pregnancy specific beta 1 glycoprotein in late pregnancy was performed to assess the influence of the presence of a high molecular weight glycoprotein with alpha 2 electrophoretic mobility (SP1 alpha) which is immunochemically identifiable with pregnancy-specific PBETA 1 glycoprotein (SP1 beta). Serum samples from 47 volunteers in the 3rd trimester of pregnancy were subjected to measurements of pregnancy specific beta 1 glycoprotein in rocket immunoelectrophoresis, quantitative crossed-immunoelectrophoresis and radioimmunoassay. Rocket immunoelectrophoresis gives a result which reflects the total SP1 content, i.e. SP1 alpha and SP1 beta while quantitative crossed-immunoelectrophoresis permits differentiation between the two molecules. Radioimmunoassay predominantly measures authenic SP1, i.e. SP1 beta in the presence of physiological amounts of SP1 alpha.
mesh_terms: D002850:Chromatography, Gel; D000939:Epitopes; D005260:Female; D006023:Glycoproteins / Q000276:immunology; D006801:Humans; D007122:Immunoelectrophoresis; D007123:Immunoelectrophoresis, Two-Dimensional; D008970:Molecular Weight; D011247:Pregnancy; D011863:Radioimmunoassay
chemical_list: D000939:Epitopes; D006023:Glycoproteins