Two-Dimensional Gel Electrophoretic Analyses of Kentucky Bluegrass and Rye Grass Pollen Allergens

Abstract

Allergenic extracts of Kentucky bluegrass (Poa pratensis) and rye grass (Lolium perenne) pollen were shown by 2-dimensional (2-D) gel electrophoresis to consist of several hundred protein components. The pollen extracts of the two related grasses had unique 2-D gel patterns. Two major grass pollen allergens, Poa p I and Lol p I, and their isoforms (i.e. isoallergens) were detected and localized on 2-D gels by immunoblotting with anti-Poa p I antibody mAb 60. Poa p I isoallergens were less acidic than Lol p I isoallergens. The relative proportion of four Poa p I isoallergens was (in decreasing pI): A, 13%; B, 37%; and D, 15%. The amino terminal amino acid sequences of the two major isoallergens of Poa p I were identical. However, the amino acid composition of these isoallergens showed enough differences to account for their charge differences. The amino terminal amino acid sequence of two major Poa p I isoallergens had a 70% homology in 20 amino acid overlap with the previously published amino terminal amino acid sequence of rye grass pollen allergen R-7.