Search

We isolated testosterone-estradiol-binding globulin (TeBG) from human pregnancy plasma and used the isolated protein to obtain a rabbit antiserum to it. Using immunochemical techniques, the antiserum was demonstrated to be both monospecific and to have the ability to remove TeBG-binding activity from human serum. This antiserum was used to develop a RIA for human TeBG. The sensitivity is such that TeBG can be determined in as little as 0.005 microliter serum or plasma, although we routinely use 0.5-1.0 microliter. The correlation between the RIA and an established binding assay, using 63 different specimens, was 0.995.

We examined the influence of numerous substances on the secretion of corticosteroid-binding globulin (CBG) and testosterone-estradiol binding globulin (TeBG) by a human hepatoma-derived cell line. Thyroxine, at physiologic concentrations, resulted in an increased secretion of TeBG but not CBG. Estrogens, antiestrogens, and androgens were without effect on either of these binding proteins.