Investigations on the ability of antisera produced by Pr-β-HCG-TT to neutralize the biological activity of HCG

Abstract

The ability of antibodies generated by the vaccine Pr-β-HCG-TT in two species of animals to neutralize the biological activity of HCG has been investigated. The antisera from an immunized goat and serveral rhesus monkeys (Macaca mulatta) abolished the HCG induced rise in ventral prostate weight of immature male rats and of uterine weight in prepubertal mice. These were also found to be effective in preventing the binding of ¹²⁵I-HCG to receptors in rat testes and goat corpora lutea preparations. The antisera also blocked the HCG induced synthesis and secretion of progesterone in corpus luteum slices in vitro. These investigations show that the antibodies elicited by the conjugate (Pr-β-HCG-TT) form a complex with HCG, which is biologically inactive.