ALLERGENIC CROSS-REACTIVITY AMONG PEACH, APRICOT, PLUM, AND CHERRY INPATIENTS WITH ORAL ALLERGY SYNDROME - AN IN-VIVO AND IN-VITRO STUDY

Background: Oral allergy syndrome In response to fruits and vegetables frequently occurs as clusters of hypersensitivity to members of the s ame botanical family, for which the immunologic basis lies in a number of common allergens, most of them still unidentified. Objective: This study was designed to assess the in vivo and in vitro cross-reactivit y between fruits of the Prunoideae subfamily (i.e., peach, cherry, apr icot, and plum) and to identify their major allergens and the cross-re activity of the peach extract with grass and birch pollen. Methods: Th e in vivo study was conducted by skin prick tests and open food challe nges with fresh fruits in 23 patients with oral allergy syndrome for p each and positive skin prick test and RAST results for the other Pruno ideae. In vitro sodium dodecylsulfate-polyacrylamide gel electrophores is was followed by immunoblotting and immunoblotting inhibition. Resul ts: A 13 kd component was identified as the only major allergen common to all the Prunoideae, the other major allergens were found at 14 kd in peach and at 30 kd in cherry. Immunoblotting inhibition showed wide cross-reactivity within the Prunoideae, whereas grass and birch polle n partially inhibited the peach blotting. Conclusions: Clinical cross- reactivity to Prunoideae is essentially due to a common 13 kd IgE-bind ing component, which seems to be the most important major allergen of this subfamily not shared with grass and birch pollen.