Title: The process of reproduction in humans: antigens for vaccine development.

POPLINE Document Number: 075890

Author(s):

Ada GL
Griffin PD

Source citation:

In: Vaccines for fertility regulation: the assessment of their safety and efficacy. Proceedings of a Symposium on Assessing the Safety and Efficacy of Vaccines to Regulate Fertility, convened by the WHO Special Programme of Research, Development and Research Training in Human Reproduction, Geneva, June 1989, edited by G.L. Ada, P.D. Griffin. Cambridge, England, Cambridge University Press, 1991. :13-26. (Scientific Basis of Fertility Regulation)

Abstract:

This review begins with a brief summary of the events of the male and female reproductive cycles, to introduce the main discussion of candidate antigens for fertility-regulating vaccine development. These potential antigens can be grouped into hormones and cell proteins. Potential hormone targets of an antifertility vaccine include GnRH, gonadotropins, gonadal hormones, and hormones made by the conceptus. Immunization against GnRH and gonadal hormones both produce unacceptable side effects. Anti-follicle stimulating-hormone (FSH) has been effective for several years in bonnet monkeys without adverse effects. Anti-luteinizing hormone (LH) immunization suppressed ovulation and implantation in several primate species, and cross reacted with the beta subunit of chorionic gonadotropin, without any adverse pathology. The most successful immunization against products of the conceptus is vaccination against the C-terminal 37 amino acid sequence of beta hCG conjugated with diphtheria toxoid, and the whole beta subunit of hCG conjugated with tetanus toxoid, now in Phase I clinical trials. The alpha subunit of hCG is identical with that of thyroid stimulating hormone (TSH), LH, and FSH, prohibiting its use in a vaccine. Cell-associated proteins from sperm, ovum, conceptus, and placenta have been the subject of research. Several sperm antigens exist, but are not candidates because of the likelihood of autoimmune orchitis. An antisperm vaccine for women would probably be safe, but it is problematical to get large amounts of the antibody at the site at each coitus. Some success has resulted by immunizing baboons against the sperm-specific isoenzyme of lactic dehydrogenase. Antiovum and early conceptus vaccines have not progressed without danger of defective development. Placental antigens would seem attractive because of the proximity of the large placental maternal blood supply. A potential vaccine candidate should be safe, effective, acceptable, reversible, free of risk of fetal damage, and without T-cell epitopes.

Keywords:

Clinical Research
Clinical Trials
Contraception Research
Contraception, Immunological
Vaccines
Gonadotropins, Chorionic
Gonadotropins, Pituitary
Follicle Stimulating Hormone
Luteinizing Hormone
Pituitary Hormone Releasing Hormones
Enzymes
Immunity, Active
Antibody Formation
Immunological Effects
Ovum
Spermatozoa
Animals, Laboratory
Fertilization
Research Methodology
Contraception
Family Planning
Gonadotropins
Hormones
Endocrine System
Physiology
Biology
Enzymes and Enzyme Inhibitors
Immunity
Immune System
Antibodies
Immunologic Factors
Germ Cells
Genitalia
Urogenital System
Reproduction