Immunological response in the primate oviduct to a defined recombinant sperm immunogen

Assessment of immune responses in the oviduct is of importance in understanding reproductive tract responses to infections, vaccination against reproductive tract pathogens, or contraceptive immunogens. This review discusses a technique that permits repeated sampling of oviductal fluid from the same monkey at intervals spanning up to several years, and the analysis of antigen-specific immunoglobulins in the fluid. This technique is important to immunocontraceptive development because previous studies in primates have lacked information on oviductal immune responses and contraceptive efficacy may not correlate well with serum antibody titers. Thus, a reliable method of sampling oviductal fluid before and after immunization with a defined antigen is required to determine the quantity and type of local immune responses necessary to achieve contraceptive effects. Implantation of access ports proved useful for repeatedly aspirating oviductal fluid in vivo from cynomolgus monkeys that was free from artifactual contaminants and with no observable changes in the behavior or health of the animals. Subsequent assays of relative and absolute concentrations of antibodies in oviductal fluid and serum demonstrated the presence of IgA and IgG specific for the recombinant sperm immunogen SP-10 in fluid collected from the periovulatory oviduct of primates after intramuscular inoculations. The antibodies evoked by the recombinant sperm vaccinogen recognized the endogenous antigen target on both human and macaque sperm, lending support for the possibility of developing a contraceptive immunogen that prevents fertilization.