Localized and systemic hypersensitivity reactions to human seminal fluid.

Reaginic humoral antibodies to human seminal plasma were present in two women with systemic reactions. In one patient, IgE antibodies were demonstrated by direct skin tests, leukocyte histamine release, passive transfer to a nonallergic human recipient, the radioallergosorbent test, inhibition of the radioallergosorbent test and neutralization of passive transfer antibodies. A similar mechanism was established in the other case by direct skin tests and antigen-induced leukocyte histamine release. Sephadex G-100 fraction 2, derived from human seminal plasma, showed greater reaginic activity than other chromatographic fractions. Two other patients with histories of localized reactions did not develop humoral antibodies but did evince cell-mediated immunity to seminal fluid antigens. One patient with localized reactions also had significant titers of IgM and IgG sperm agglutinating antibodies to seminal plasma. Both reaginic and cell-mediated sensitization to human sperm extract were also observed in this series of patients. Histocompatibility leukocyte antigen (HLA) typing of all patients and their sexual partners showed a marked degree of shared histocompatibility focus antigens in members of each of two couples.