Comparison of the antigenic and allergenic properties of three types of bovine epithelial material.

The antigenic and allergenic characteristics of three bovine epithelial extracts, dander, skin scrapings and whole skin, were compared using IgE-ELISA inhibition and SDS-PAGE with immunoblotting. Cow dander extract was shown to contain more allergenic activity than skin scrapings or whole skin extracts which were needed in about three times higher amounts than cow dander extract to induce the same degree of inhibition in ELISA. Skin scrapings and whole skin extracts contained more high-molecular weight components than dander extract. These components were at least partly serum-derived and reacted often with the IgG but not with the IgE of both the cow-asthmatics and their control subjects. The antigenic characteristics of the low-molecular weight components as well as the allergenic qualities of these three epithelial preparations were generally similar. Using the sera of 49 cow-asthmatic farmers, two major allergens were detected at 20 and 22 kD in all three extracts. Our results show that the highest amount of allergenic material and all the essential allergens are present in cow dander extract. In addition, the normally non-allergenic high molecular weight components are detected in low concentrations in dander extract. Therefore it is concluded that cow dander extract is the best alternative for allergen purification and allergen extract preparation.