In vitro studies of human seminal plasma allergy

Abstract

A 23-yr-old woman experienced generalized urticaria, angioedema, and respiratory obstruction after intercourse. Reactions increased in frequency and severity over a 2-yr period; sexual exposures were limited to her husband. Fresh, centrifuged seminal plasma samples from four donors, including her husband, evoked positive immediate puncture skin-test reactions in dilutions of 1:100 or 1:1,000; no reactions were seen in normal control males. A borderline elevation in serum IgE antibodies to seminal plasma was noted by the radioallergosorbent test (RAST). However, the patient had elevated IgE antibodies to a partially purified seminal plasma fraction (IV) obtained by Sephadex G-200 gel filtration. Seminal plasma from all four donors showed similar allergenic activity when tested in fraction IV RAST inhibition experiments. Further in vitro studies have characterized the allergenic components infraction IV. Allergenic components (pool III) (1) are distinct from acid phosphatase; (2) have an apparent molecular weight range from 20,000 to 30,000 daltons; (3) by isoelectrofocusing produced multiple bands with pi of 6.6, 7.0, and 7.5; and (4) produced multiple bands in polyacrylamide gel electrophoresis, indicating a heterogeneous group of antigens. Comparison of pool III with seminal vesicle secretions and prostatic homogenate via thin-layer isoelectrofocusing revealed protein bands which appeared to be common to all three materials. Thus, it remains uncertain as to whether allergenic proteins are derived from seminal vesicle or prostatic secretions. Condom usage by the patient's husband has essentially prevented subsequent allergic reactions. However, serum IgE antibodies to fraction IV remained consistently elevated during a 28-mo follow-up period.