Distribution of a major allergen of rye grass (Lolium perenne) pollen between other grass species.

Polyacrylamide gel electrophoresis in sodium dodecyl sulphate (SDS) followed by protein staining has shown that extracts from 11 different grass pollens contained proteins with similar molecular weights to that of the allergen R7 from rye grass (Lolium perenne) pollen extract (i.e. 29,000-31,000 daltons). Western blotting and detection with polyclonal (rabbit) antibodies raised against the purified R7 (Rye I) allergen indicated that these proteins were antigenically related and their allergenic properties were demonstrated by the binding of human IgE to immunoblots. The distribution of cross-reacting antigenic determinants was further investigated by immunoblotting with 2 mouse monoclonal antibodies, R7M1 and R7M2, produced with purified R7 as the initial immunogen. The 2 monoclonal antibodies were shown to react with 'R7-like' components of grass pollen extracts other than the component from rye grass. Differences in the distribution of R7M1 and R7M2 binding were found indicating that they are directed at separate R7 epitopes.