title: Purification of pregnancy-associated plasma protein-A by a two step affinity chromatographic procedure.
abstract: A high molecular weight pregnancy specific protein (PAPP-A) was purified by immunospecific affinity chromatography. The purification procedure was based on a new method for affinity chromatography using direct coupling of precipitable immune complexes to the gel matrix. The procedure was performed in two steps: a positive immunospecific affinity chromatography followed by a negative affinity chromatography in which balanced amounts of anti-contaminant antibodies were used as ligant. The purified material at a concentration of 300 microgram/ml was tested by immunoelectrophoretic methods and no contaminants were detectable. WHO beta-1 SP1 reference material 78610 contained 45 microgram PAPP-A/ml.
mesh_terms: D000917:Antibody Formation; D002846:Chromatography, Affinity / Q000379:methods; D005260:Female; D006801:Humans; D007122:Immunoelectrophoresis; D007163:Immunosorbent Techniques / Q000379:methods; D008297:Male; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000302:isolation & purification*; D011266:Pregnancy-Associated Plasma Protein-A / Q000302:isolation & purification*
chemical_list: D011257:Pregnancy Proteins; D011266:Pregnancy-Associated Plasma Protein-A