Cross-reactivity of Antibody to Human and Bovine Luteinizing Hormone (LH) with Homologous and Heterologous LH1

Antibodies to highly purified human and bovine pituitary luteinizing hormone (LH) have been produced in the rabbit, and their presence has been confirmed by biological neutralization and in vitro immunologic techniques. 2. Antibodies to human LH inhibited the biological activity of human pituitary and postmenopausal urinary LH and human chorionic gonadotropin, and gave positive immunologic reactions with these hormones. Antibodies to human LH did not inhibit the biological activity of bovine, porcine, equine or ovine pituitary LH, or of pregnant mare serum gonadotropin, nor were immunologic cross-reactions observed with LH from these sources. 3. Antibodies to bovine LH inhibited the biological activity of bovine, ovine, porcine and equine pituitary LH, pregnant mare serum gonadotropin, human pituitary and postmenopausal urinary LH and human chorionic gonadotropin. Positive immunologic reactions, however, were only detected with bovine and porcine pituitary LH fractions, and with ovine pituitary LH both before and after inactivation of biological activity with hydrogen peroxide. 4. It required significantly more bovine LH antibody to neutralize human pituitary LH than an equivalent amount of the homologous hormone. (Endocrinology 81: 591, 1967)