Isolation and characterization of a major cross-reactive grass group I allergenic determinant.

A series of peptides has been isolated from the Group I (GpI) allergen from five species of grasses currently under study in this laboratory. These peptides were generated by performing a limited tryptic digestion on each extensively reduced and alkylated GpI allergen and fractionating the digest by molecular sieve, ion-exchange and HPLC reverse-phase chromatography. Material in the elution profiles was assayed with a monoclonal antibody known to cross-react with all GpI allergens in this study. In addition, this particular monoclonal antibody has been previously shown to inhibit the ability of human IgE to bind to these GpI allergens. The peptides identified and isolated in this way were found to be highly homologous to one another.