Bioassay for anti-chorionic gonadotrophin sera

Area of Science:

• Reproductive endocrinology
• Immunology
• Bioassay development

Background:

• Human chorionic gonadotrophin (hCG) plays a crucial role in maintaining pregnancy.
• Neutralizing antibodies against hCG are important for fertility control and diagnostic applications.
• Existing bioassays for neutralizing antibodies can be time-consuming and complex.

Purpose of the Study:

• To develop and validate a rapid bioassay for quantifying the neutralizing activity of anti-hCG sera.
• To assess the efficacy of antisera raised against ovine luteinizing hormone beta-subunit (oLH beta) in neutralizing hCG activity.
• To establish a dose-response relationship for antibody neutralization in vivo.

Main Methods:

• A bioassay was developed using male mice to measure plasma testosterone concentrations.
• Inhibition of hCG-induced testosterone increase was measured after administering antichorionic gonadotrophin sera.
• Antisera were generated in rhesus monkeys immunized against oLH beta, and also obtained from humans, chimpanzees, and rabbits.

Main Results:

• The bioassay demonstrated a clear inhibition of hCG-induced testosterone stimulation by anti-oLH beta sera.
• A dose-response relationship was established, showing neutralization between 25 and 200 microliters of antiserum.
• Anti-hCG sera from various species (human, chimpanzee, rabbit) also effectively neutralized hCG's biological activity.

Conclusions:

• The developed bioassay provides a rapid and efficient method for assessing the neutralizing activity of anti-hCG sera.
• In vivo hormone-antibody reactions are effectively studied through a single antiserum injection prior to hCG administration.
• This method is valuable for research and development of hCG-based diagnostics and therapeutics.