Characterization of allergens in kiwi fruit and detection of cross‐reactivities with allergens of birch pollen and related fruit allergens

Abstract

The sera of 29 patients who suffered from pollen-related food hypersensitivities and complained of allergic reactions to kiwi fruit and other tropical fruits were tested for specific IgE antibodies against kiwi fruit, apple, carrot, celery and birch pollen using an enzyme allergosorbent test (EAST). In 20 sera, specific IgE antibodies were detected against all five extracts. Sodium dodecyl sulphate polyacrylamide gel electrophoresis/ immunoblot of kiwi fruit extract revealed two major allergens with molecular weights of approximately 43 and 67 kDa. In EAST inhibition assays, cross-reactivities between kiwi fruit, apple, birch pollen and, to a lesser degree, carrot and celery were demonstrated. The cross-reactivities seen between kiwi fruit, birch pollen and apple were not caused by the major allergen of birch pollen (Bet v 1). Allergens with molecular weights of approximately 68 kDa in birch pollen and 67 kDa in apple cross-reacted with the allergens of kiwi fruit, as demonstrated by immunoblotinhibition. Profilins, which are known plant pan-allergens, do not seem to be relevant allergens in kiwi fruit.

Influence of Varieties, Storage and Heat Treatment on IgE-Binding Proteins in Hazelnuts (Corylus avellana)

“…The disks were washed again and enzyme activity was stained with p-nitrophenylphosphate (PNPP) for 60 min at 37°C. Absorbance was measured at 405 nm (Möller et al, 1997).…”

“…Proteins of the allergen extracts of hazelnuts of the Barcelona variety were coupled to these disks by a modified procedure described by Möller et al (1997).…”

Identification of a 28 kDa lychee allergen as a triose-phosphate isomerase

“…The low-temperature method (Vieths et al 1992, Mö ller et al 1997) allows the separation of interfering phenolic compounds from the proteins and the reduction of enzymatic activities. Allergens with molecular weights of 28,35,40,43,55,70 kDa are important lychee allergens because they could be stained in immunoblot with more than 50% of patients' sera.…”

“…Serum from a nonatopic patient was used as negative control. Immunostaining was performed according to Vieths et al (1992) and Mö ller et al (1997). Molecular weights were determined by a protein standard mixture (14.4 Á/ 94.0 kDa) after silver staining or, on nitrocellulose membranes, after Ponceau S staining.…”

“…Extracts were prepared from fresh lychees without peel and stone by a previously described low-temperature method (Vieths et al 1992, Mö ller et al 1997. Proteins were extracted from the obtained acetone powder with phosphate-buffered saline (PBS) for EAST and immunoblot investigations and with bidistilled water for ion exchange chromatography (IEC).…”