Specific Antibodies to Triiodothyronine Hormone

WE have been able to stimulate the formation in rabbits of a very specific antibody against triiodothyronine (T3) by injecting the animals with a condensation product of T3 and succinyl poly-L-lysine. Antibodies against thyroxine (T4) have been obtained by Clutton, Harington and Yuill1 and by Churchill and Tapley2 using conjugated hapten–protein antigens, but the use of natural proteins as carriers may be the reason for the rather low specificity of the resulting antibodies. We prepared succinylated poly-L-lysine by the method of Stason, Vallotton and Haber3, and reacted it by carbodiimide condensation with the methyl ester of T3. After saponification a highly specific antigen was obtained.