COMPARISON OF IGE-BINDING ANTIGENS IN HORSE DANDER AND A MIXTURE OF HORSE HAIR AND SKIN SCRAPINGS

Extracts of horse dander (HD) and horse hair and skin scrapings (HHSS) have been compared with respect to their content of proteins and carb ohydrates. The protein content of HD is more than double that of HHSS, while the carbohydrate content is of the same order. SDS-PAGE and IEF , both combined with immunoblotting, and CIE/CRIE showed the IgE-bindi ng ability of the proteins/glycoproteins present in the two extracts. SDS-PAGE/immunoblotting showed the presence of mainly the same IgE-bin ding bands in the two extracts. Nine were detected in HD, and seven in HHSS. Four of these were glycoproteins. The most important allergen w as a glycoprotein with molecular mass of 27 kDa showing IgE-binding ab ility to the 16 patient sera available. Another important allergen wit h molecular mass of 67 kDa is probably horse albumin. IEF/immunoblotti ng showed the presence of a glycoprotein with IgE-binding ability at p H 3.2 in both extracts. Tandem CRIE showed that both extracts containe d the same four allergens as major allergens. In addition, as we obser ved when analyzing both extracts in CRIE against 16 different patient sera, each extract contained allergens not present in the other extrac t. We may conclude from this investigation that commercial allergen ex tracts to be used in diagnosis and immunotherapy should include both h orse dander and horse hair and skin scrapings in the starting material for the preparation of extracts. If not, allergens which may be of im portance for some patients will be missing.