Glycoprotein allergens in pollen of timothy. II. Isolation and characterization of a basic glycoprotein allergen.

A basic glycoprotein allergen has been isolated from pollen of timothy by a combination of chromatography on columns of CM-Sepharose CL-6B, Bio-Gel P-30, DEAE-Sepharose CL-6B and Ultrogel AcA 44. The allergen which is immunologically identical with the allergen formerly denoted as antigen 30 had an isoelectric point of 9.45. The MW of the glycoprotein was found to be 54,000 and 38,000 by SDS-PAGE and gel filtration, respectively. The allergen contains arabinose (3.1%), fucose (0.7%), xylose (0.7%), mannose (2.1%), galactose (2.8%) and glucose (0.2%). In rocket radioimmunoelectrophoresis the allergen bound IgE from 57 (78%) of 73 patient sera tested. The allergen did not bind Yariv artificial galactosyl- and glucosyl-carbohydrate-binding antigens or a monoclonal antibody against ryegrass pollen glycoprotein allergens.