title: Characteristics of antibodies against 17 beta-oestradiol in homologous and heterologous systems of radioimmunoassay.
abstract: Directly iodinated oestradiol-2(4)-iodo-[125I] and oestradiol-6-O-(CMO)-[125I]iodohistamine were prepared and used in conjunction with anti-oestradiol-2(4)-azo and anti-oestradiol-6-O-(CMO) sera for the development of various radioimmunoassay (RIA) systems which showed marked differences in sensitivity and relatively small differences in specificity. Whereas the heterologous combination of oestradiol-6-O-(CMO)-[125I]iodohistamine and anti-oestradiol-2(4)-azo-serum showed a sensitivity expressed in femtograms, the homologous combination using oestradiol-6-O-(CMO)-[125I]iodohistamine radioligand exhibited a sensitivity two orders lower. The specificity of both the heterologous and homologous system did not differ significantly from the RIA system using tritiated radioligand. The combination of directly iodinated oestradiol and anti-oestradiol-2(4)-azo-serum showed a higher sensitivity and a lower specificity as compared with tritiated radioligand.
mesh_terms: D000906:Antibodies; D000936:Antigen-Antibody Complex; D004958:Estradiol / Q000031:analogs & derivatives* / Q000032:analysis / Q000276:immunology; D006801:Humans; D007457:Iodine Radioisotopes; D011863:Radioimmunoassay / Q000379:methods; D012709:Serum Albumin; D014316:Tritium
chemical_list: D000906:Antibodies; D000936:Antigen-Antibody Complex; D007457:Iodine Radioisotopes; D012709:Serum Albumin; D014316:Tritium; D004958:Estradiol; C016430:17 beta-estradiol hemisuccinate