Studies on Immunological Assay of Urinary Estrogens. I. Preparation and Immunological Properties of Antisera and Determination of Urinary Estrogens by Radioimmunoassay

Open Access
Publisher Website
Google Scholar
Abstract
Estriol antisera were raised and studied for the use in radioimmunoassay (RIA) of urinary estrogen as an aid of diagnosis of feto-placental function. Antisera to estriol-related 6 haptens, i.e., estriol 16-glucuronide (E3-16-G), estriol 16-hemisuccinate (E3-16-succ), estriol 17-hemisuccinate (E3-17-succ), estriol 16,17-dihemisuccinate (E3-16,17-succ), estriol 3-carboxymethylether (E3-3-CME) and estriol 3-glucuronide (E3-3-G), were obtained by immunizing rabbits with the respective hapten-bovine serum albumin (BSA) conjugate. Antiserum to E3-16-G-BSA reacted significantly with E3-16-G, C-17 conjugated estrogens and free estrogens. But it did not react with C-3 conjugated estrogens and other steroids. Similar properties were observed with antisera to E3-16-succ-BSA, E3-17-succ-BSA and E3-16,17-succ-BSA but their reactivities with C-16 or C-17 conjugated estrogens were slightly lower than that of anti-E3-16-G-BSA serum. Among antisera which were raised against estriol linked to BSA via hemisuccinate varying in linking position, anti-E3-16-succ-BSA serum highly reacted with E3-16-G, while anti-E3-17-succ-BSA did with E3-17-G. Anti-E3-16,17-succ-BSA serum reacted with C-16 and C-17 conjugated estrogens to nearly the same extent. Antisera to E3-3-CME-BSA and E3-3-G-BSA reacted with estrogens conjugated at C-3 position but failed to react with C-16 or C-17 conjugated estrogens. The latter antiserum reacted more specifically with E3 and E3 3-G than the former. Estrogen values in pregnancy urine samples estimated by the RIA by use of anti-E3-16-G serum were not influenced by other components in urine and showed a good correlation of y = 0.81x - 1.28, r = 0.983 with those determined by the currently available colorimetric method with E3-kit.