Guinea-pig-derived allergens. Clinicoimmunologic studies, characterization, airborne quantitation, and size distribution.

Of 20 serum samples from laboratory workers who experienced allergic symptoms after exposure to laboratory animals, 9 contained elevated IgE antibodies to guinea pig urine, pelt, or albumin by the radioallergosorbent test (RAST). Skin testing documented allergenic activity with all 3 guinea pig allergens. The cross-reactivity of these 3 guinea pig allergens was studied in RAST inhibition assays. Guinea pig pelt extract and urine produced dose-related inhibition in all 3 assays, but guinea pig albumin was inhibitory in only the homologous assay. Characterization by gel filtration, polyacrylamide gel electrophoresis, and isoelectric focusing demonstrated heterogeneity of the allergens. Air filter samples were taken in a guinea pig housing room, a research laboratory, and a library, using a high volume air sampler. An outdoor air filter sample was also taken. Guinea pig urine allergen activity was detected in all indoor air filter samples by RAST inhibition. Guinea pig pelt allergen activity was detected in all air filter samples, except the library and outdoors. Guinea pig albumin was not detected in any air filter sample. Sizing of airborne particles demonstrated that most guinea pig allergen activity was associated with particles of a diameter greater than 5 mu and less than 0.8 mu. Urine appears to be the major source of guinea pig allergens, and it is present in airborne particles small enough to penetrate the lower respiratory tract when inhaled.