Allergy to human seminal fluid: characterization of the allergen and experience with immunotherapy.

A 20-year-old woman was observed with a history of a severe generalized systemic reaction after topical contact with seminal fluid. A prick test with undiluted seminal fluid produced a 5.0 mm wheal-and-flare response with pseudopods. Prick tests with saliva and serum from the same source as the seminal fluid were negative. Measurement of IgE antibody to seminal-fluid allergen with a Biotin-Avidin ELISA technique yielded strong activity. No IgG antibody could be detected. Significant prick test reactivity could be found in Sephadex G-100 fractions that had a molecular weight range of 12,000 to 75,000 daltons and that contained approximately 5% of the total protein in the starting material. Isoelectric focusing fractions with strong skin test reactivity had a pI range of 5.4 to 6.6. These fractions contained one major protein band. Immunotherapy was conducted with a Sephadex fraction of seminal fluid during a 24-month period. A cumulative dose of 32 mg of protein was administered. No side effects other than local swelling occurred. Ten months after the start of immunotherapy, IgE antibody became unmeasureable, an effect that was demonstrated not due to the inhibitory effect of IgG antibody. IgG antibody rose progressively in this period. Clinically, the patient became less sensitive to topical contact. Although the natural history of seminal-fluid allergy is not known, immunotherapy may be effective.

Cat allergen content of commercial house dust extracts: comparison with dust extracts from cat-containing environment.

Eighteen lots of house dust extract from nine commercial sources (obtained as weight per volume or protein nitrogen unit per cubic centimeter) were analyzed for cat allergen content by direct quantitative immunoelectrophoresis after concentration. Cat allergen 1 was measurable (greater than 0.3 units) in 11 extracts with a mean (range) of 5.8 (1.3 to 31.0) U/gm of source material. Cat albumin was measurable (greater than 2.4 units) in 12 extracts with a mean (range) of 53.4 (11.5 to 319.7) U/gm. In order to evaluate whether the cat allergen 1 content is a significant contribution to the allergenic activity of the extract, 17 cat-allergic subjects were tested by prick test with a purified preparation of cat allergen 1. The mean (range) concentration that produced a 3 mm wheal was 0.01 (0.0013 to 1.33) U/ml. Therefore, the commercial house dust extracts studied, when these extracts were diluted to a concentration commonly used for prick testing, would frequently contain enough cat allergen 1 to produce strong prick test reactions in cat-allergic subjects. It is difficult to justify the use of such commercial dust extracts as diagnostic reagents. For comparison purposes, nine dust samples from an apartment housing two cats were similarly analyzed. Cat allergen 1 was measurable in seven samples with a mean (range) of 23.8 (1.8 to 64.3) U/gm. Cat albumin could be measured in all nine samples with a mean (range) of 32.3 (0.16 to 70.8) U/gm. The average amount of cat allergen 1 that could be washed off the surface of the cats was 270 units. Large reservoirs of cat allergen 1 were present.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunologic and biochemical properties of the major mouse urinary allergen (Mus m 1).

Rabbit antiserum to the mouse major urinary protein identified a single antigen that was also found in mouse serum and pelt extract. The skin test reactivity of mouse-pelt extract and mouse urine in two mouse-allergic subjects was significantly reduced after immunoabsorption with the gamma globulin fraction of this antiserum. The antigen defined by this antiserum was designated mouse allergen 1 (MA1). An immunoelectrophoretic procedure was set up to measure its concentration. MA1 had a molecular weight of approximately 19,000 on Sephadex gel filtration and 18,000 to 21,000 on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Isoelectric focusing identified at least four bands with antigenic activity; the major band had an isoelectric point of 3.9. Significant antigenic and allergenic activity of MA1 was retained on reduction and digestion with papain and pepsin. Heating at 90 degrees C for periods up to 180 minutes resulted in a progressive loss, but not abolition, of activity. Serum and urine derived from male mice contained approximately fourfold more MA1 than samples derived from female mice. Urine contained at least 100-fold more MA1 than serum. Of the tissue extracts studied, liver extract had the highest amount of MA1. The immunochemical properties of MA1, its tissue distribution, and sex differences in its concentration provide strong evidence that MA1 is identical to the previously described mouse major urinary protein.