The immune response of the genital tract of the female rabbit following systemic and local immunization.

Female rabbits were immunized with a model antigen, horseradish peroxidase (HRP), either locally in the reproductive tract or systemically via the intramuscular route. A sensitive immunoassay was developed to detect antibodies to the HRP in both serum and reproductive tract flushings. Systemic immunization resulted in circulating and reproductive tract antibodies of the IgG class, but none of the IgA class. Local immunization produced IgA and IgG antibodies in the reproductive tract, and also IgG antibodies in serum. Cell-mediated immunity was examined by circulating lymphocyte transformation and skin sensitivity to HRP. Cell-mediated immune responses occurred after systemic immunization, but not after local immunization. The relevance of the results to immunological methods of fertility control is discussed.