title: Two new variants of the lipocalin allergen Bos d 2.
abstract: Allergens from various sources have been shown to comprise several isoforms. In the present study, a series of chromatographic steps was carried out to separate the lipocalin allergen Bos d 2 isoforms present in cow dander. Subsequent HPLC-MS-MS analyses revealed two new Bos d 2 variants. In one of the proteins, tyrosine (Y83) was substituted by aspartic acid, and in the other protein valine (V102) was replaced by alanine. We propose the three Bos d 2 variants be named as Bos d 2.0101 (previously sequenced Bos d 2), Bos d 2.0102 and Bos d 2.0103. Our results suggest that molecular polymorphism is a common property among lipocalin allergens. Since allergen isoforms may show variation in their IgE binding and/or T-cell reactivity, all of the many allergen forms should be taken into account when planning preparations for immunotherapy.
authors.affiliation: The Department of Clinical Microbiology, University of Kuopio, Finland. jaakko.rautiainen@uku.fi
authors.forename: J
authors.initials: J
authors.lastname: Rautiainen
authors.forename: S
authors.initials: S
authors.lastname: Auriola
authors.forename: A
authors.initials: A
authors.lastname: Konttinen
authors.forename: T
authors.initials: T
authors.lastname: Virtanen
authors.forename: M
authors.initials: M
authors.lastname: Rytkönen-Nissinen
authors.forename: T
authors.initials: T
authors.lastname: Zeiler
authors.forename: R
authors.initials: R
authors.lastname: Mäntyjärvi
mesh_terms: D000485:Allergens; D000595:Amino Acid Sequence; D000818:Animals; D052179:Antigens, Plant; D002352:Carrier Proteins / Q000737:chemistry* / Q000276:immunology; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D000485:Allergens; D052179:Antigens, Plant; C113339:Bos d 2 allergen; D002352:Carrier Proteins