Choriogonadotropin and immunity: a reevaluation

Area of Science:

• Immunology
• Endocrinology
• Reproductive Biology

Background:

• Immunosuppressive activity of human chorionic gonadotropin (hCG) preparations has been debated.
• In vitro studies often attribute immunosuppression to contaminants in hCG preparations.
• Recent in vivo data suggest a different mechanism.

Purpose of the Study:

• To clarify the in vivo immunosuppressive activity of purified and recombinant hCG.
• To investigate the role of the gonad in hCG-mediated immunosuppression.

Main Methods:

• Analysis of hCG preparations' immunosuppressive activity using various techniques.
• In vivo studies utilizing a murine delayed-type hypersensitivity model.
• Comparison of immunosuppressive effects in intact versus castrate mice.

Main Results:

• Highly purified and recombinant hCG preparations demonstrate immunosuppressive activity in vivo.
• This in vivo immunosuppression was not observed in castrate mice.
• Contaminants are likely responsible for in vitro immunosuppressive effects.

Conclusions:

• The hCG molecule can induce immunosuppression in vivo.
• This effect appears to be indirect, mediated through the gonad.
• Distinguishes between in vitro and in vivo effects of hCG preparations.