Bet v 1 homologues in strawberry identified as IgE-binding proteins and presumptive allergens
Version of Record online: 11 OCT 2004
Volume 59, Issue 12, pages 1277–1284, December 2004
How to Cite
Karlsson, A. L., Alm, R., Ekstrand, B., Fjelkner-Modig, S., Schiött, Å., Bengtsson, U., Björk, L., Hjernø, K., Roepstorff, P. and Emanuelsson, C. S. (2004), Bet v 1 homologues in strawberry identified as IgE-binding proteins and presumptive allergens. Allergy, 59: 1277–1284. doi: 10.1111/j.1398-9995.2004.00585.x
- Issue online: 26 OCT 2004
- Version of Record online: 11 OCT 2004
- Accepted for publication 31 March 2004
- clinical immunology;
- food allergy;
Background: No strawberry allergen has so far been identified and characterized.
Methods: Serum samples were collected from patients with a suggestive case history of adverse reactions to strawberry and other fruits. Extracts from fresh and frozen strawberries were analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blotting and mass spectrometry. Patient blood samples were analysed for inhibition of IgE binding and basophil degranulation.
Results: Several IgE-binding proteins could be detected. In more than half of the patient sera, a 20/18-kDa doublet band was observed in Western blotting. These two bands were excised and analysed by mass spectrometry showing the presence of proteins belonging to the Bet v 1 family of allergens. Inhibition of the IgE binding to the 20/18-kDa doublet was obtained by addition of two recombinantly expressed allergens belonging to the Bet v 1 family (Bet v 1 and Mal d 1) and strawberry protein extract. In a cell-based assay of patient blood samples, basophil degranulation could be induced by strawberry protein extract and by Bet v 1 and Mal d 1.
Conclusions: We conclude that strawberry homologues to Bet v 1 may be allergens of importance for adverse reactions to strawberry.