[Relationship between IgE antibodies to recombinant allergens rBet v 1 and rBet v 2 and food causing oral allergy syndrome in cases of birch-pollen allergy].
BACKGROUND
Persons allergic to birch pollen often report oral and pharyngeal hypersensitivity to fruit and vegetables, such as apples and peaches due to immunological cross-reactivity, or oral allergy syndrome (OAS) sometimes accompanied by systemic reaction. Such cross-reactive antigen reactions involve Bet v 1, the main birch-pollen allergen, and Bet v 2, birch-pollen profilin. We evaluated the food/antigen relationship.


METHODS
Subjects interviewed numbered 60-40 women and 20 men aged 12 to 70 (mean age: 35 years)-suffering OAS episodes and having IgE birch-pollen antibodies. Using CAP scoring we examined IgE antibodies to recombinant Bet v 1 (rBet v 1), recombinant Bet v 2 (rBet v 2), and recombinant Pru p 3 (rPru p 3) a peach lipid transfer protein (LTP). A CAP score of 0.35 or more was considered positive. We evaluated the relationship between recombinant allergens and 9 fruit often involving OAS--apple, peach, cherry, kiwi, pear, melon, plum, strawberry, and watermelon-based on subjects' reports.


RESULTS
Of the 60, all (100%) were rBet v 1-positive, 9 (15%) rBet v 2-positive, and none (0%) rPru p 3-positive. Rose-family fruit-apples, peaches, cherries, pears, plums, and strawberries-often caused OAS regardless of positive or negative rBet v 2 CAP and were associated with rBet v 1. In contrast, more of those who were rBet v 2 CAP-positive had OAS to non-rose-family fruit-melon and watermelon-than those rBet v 2-negative. In rose-family and non-rose-family classification of the 9 fruit, cluster analysis and kappa statistics showed non-rose-family melon, watermelon, and kiwi to be associated with rBet v 2, as were grass and mugwort pollen allergies.


CONCLUSIONS
Bet v 1 is associated with OAS due to rose-family fruit and Bet v 2 with OAS due to non-rose-family fruit.
Yamamoto
Tetsuo
T
Yamamoto ENT Clinic, Sapporo.
Asakura
Kohji
K
Shirasaki
Hideaki
H
Himi
Tetsuo
T
D000293:Adolescent; D000328:Adult; D000368:Aged; D000906:Antibodies / Q000032:analysis*; D052179:Antigens, Plant / Q000276:immunology*; D001072:Apraxias; D029662:Betula / Q000276:immunology*; D002648:Child; D003429:Cross Reactions; D005260:Female; D005512:Food Hypersensitivity / Q000276:immunology*; D005638:Fruit / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins; D006255:Rhinitis, Allergic, Seasonal / Q000276:immunology*; D014675:Vegetables / Q000276:immunology
D000906:Antibodies; D052179:Antigens, Plant; D011994:Recombinant Proteins; D007073:Immunoglobulin E