title: Coupling of delta 5,3-ketosteroid isomerase to human placental lactogen with intermolecular disulfide bond formation. Use of this conjugate for a sensitive enzyme immunoassay.
abstract: An immunoassay for human placental lactogen (HPL) has been developed with the use of hormone labelled with delta 5,3-ketosteroid isomerase. The enzyme is coupled to the antigen via an intermolecular disulfide interchange reaction. HPL-enzyme conjugates are prepared in high yield and purified by affinity chromatography. An enzyme immunoassay using these hormone-enzyme derivatives is compared with radioimmunoassay for determination of HPL in serum.
mesh_terms: D000818:Animals; D002417:Cattle; D002846:Chromatography, Affinity; D004220:Disulfides / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007535:Isomerases / Q000494:pharmacology*; D010928:Placental Lactogen / Q000494:pharmacology*; D011247:Pregnancy; D011863:Radioimmunoassay; D013251:Steroid Isomerases / Q000494:pharmacology*
chemical_list: D004220:Disulfides; D010928:Placental Lactogen; D007535:Isomerases; D013251:Steroid Isomerases