title: The production and characterisation of antisera to 17-hydroxyprogesterone.
abstract: Sheep were immunised with 11-deoxycortisol-21-hemisuccinate-bovine serum albumin (11-deoxycortisol-21-HS-BSA) or with 17-hydroxyprogesterone-7 alpha-carboxyethyl thioether-keyhole limpet haemocyanin (17-OHP-7 alpha-CETE-KLH) or with 17-OHP-3-(O-carboxymethyl)oxime-KLH (17-OHP-3-CMO-KLH). The resultant antisera were assessed using [3H]17-OHP and dextran-coated charcoal to separate the antibody bound and free fractions. All sheep produced antisera with an apparent affinity constant of from 1.4 to 6.6 X 10(9) 1/mol. Those raised against 11-deoxycortisol-21-HS-BSA had titres ranging from 1:12,000 to 1:78,000 but showed significant cross-reactivity with many of the steroids tested. Sheep immunised with 17-OHP-7 alpha-CETE-KLH had antisera titres of from 1:102,000 to 1:180,000 and only 17-hydroxypregnenolone cross-reacted significantly (10-20%). The best antisera were raised in sheep immunised with 17-OHP-3-CMO-KLH. Titres ranged from 1:168,000 to 1:390,000 and there were about 8 g/l of specific antibodies which cross-reacted 5.7% or less with 17-hydroxypregnenolone, and less than 0.5% with progesterone, 11-deoxycortisol and the other steroids studied. The antisera to 17-OHP-3-CMO-KLH were further assessed using [125I]17-OHP; titres ranged from 1:5,700,000 to 1:18,000,000 with affinity constants of from 1.67 to 2.5 X 10(10) 1/mol. They showed minimal or no cross-reactivity with the steroids studied. Reimmunisation after an 8-month interval produced antisera with a higher affinity constant and even lower cross-reactivity with other steroids.
mesh_terms: D019326:17-alpha-Hydroxyprogesterone; D000818:Animals; D000918:Antibody Specificity; D000941:Antigens / Q000276:immunology; D003350:Cortodoxone / Q000276:immunology; D006433:Hemocyanins / Q000276:immunology; D006908:Hydroxyprogesterones / Q000276:immunology*; D007106:Immune Sera / Q000276:immunology*; D007114:Immunization; D007457:Iodine Radioisotopes; D012710:Serum Albumin, Bovine / Q000276:immunology; D012756:Sheep / Q000276:immunology; D014316:Tritium
chemical_list: D000941:Antigens; D006908:Hydroxyprogesterones; D007106:Immune Sera; D007457:Iodine Radioisotopes; D014316:Tritium; D012710:Serum Albumin, Bovine; D019326:17-alpha-Hydroxyprogesterone; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin; D003350:Cortodoxone