Isolation and characterization of a glycoprotein allergen, Art v II, from pollen of mugwort (Artemisia vulgaris L.).

Abstract A glycoprotein allergen, Art v II, was isolated from pollen of mugwort by two different isolation procedures. Art v II-A was isolated by a combination of ion-exchange chromatography on DEAE-Sepharose, affinity chromatography on Con A-Sepharose and ion-exchange chromatography on Mono P. Art v II-B was isolated by a combination of preparative IEF in Ultrodex granulated gel, affinity chromatography on Con A-Sepharose and HPLC size exclusion on Ultropac TSK G2000SW. Art v II-A and Art v II-B were shown to be antigenically identical with the allergen we have formerly denoted Ag7. The MW of Art v II A/B was determined to be 34,000–38,000 by HPLC size exclusion, and 35,000 and 20,000 by SDS-PAGE under non-reducing and reducing conditions, respectively. An v II was found to consist of 6(7) isoforms with pI 4.10, 4.20 (major component), 4.35, 4.45, 4.55, 4.65, (4.80). The glycoprotein allergen had a protein to carbohydrate ratio of 10:1 and the carbohydrate part contained mannose (70.7%), N -acetyl-glucosamine (17.0%), glucose (7.0%) and galactose (5.3%). In R(R)IE the purified allergen bound IgE from 5 (33%) of 15 sera from patients with clinical allergy against mugwort pollen and from 13 (52%) of 25 sera from patients selected only on the basis of a RAST-class 4 against mugwort pollen.