Antibody to human follicle-stimulating hormone: cross-reactivity with three other hormones.

Antibodies directed against human follicle-stimulating hormone (FSH) were demonstrated in rabbit serum by neutralization of biological activity. Antibodies that bound FSH-(131)I were produced in rabbits and guinea pigs by repeated injections of FSH. By (131)I immunochemical methods, we found that at least 90% of the FSH-(131)I-binding antibody failed to distinguish the four human glycoprotein hormones: FSH, luteinizing hormone, chorionic gonadotropin, and thyrotropin, purified as well as endogenous hormone in plasma. Neither growth hormone, adrenocorticotropin, nor a variety of glycoproteins or animal plasmas were able to react with these antibodies.