Quantitative IgE inhibition experiments with purified recombinant allergens indicate pollen-derived allergens as the sensitizing agents responsible for many forms of plant food allergy
L. Kazemi-shirazi et al., Quantitative IgE inhibition experiments with purified recombinant allergens indicate pollen-derived allergens as the sensitizing agents responsible for many forms of plant food allergy, J ALLERG CL, 105(1), 2000, pp. 116-125
Background: Type I allergic symptoms in the oropharyngeal mucosa upon conta
ct with plant-derived food in patients with pollen allergies have been term
ed oral allergy syndrome (OAS). IgE cross-reactivity between pollen and foo
d allergens represents the molecular basis for this phenomenon. The sensiti
zing allergen source (pollen or plant Toed) in OAS is a controversial issue
.
Objective:We sought to determine the primary sensitizing molecules in patie
nts with GAS.
Methods: We used recombinant birch pollen (rBet v 1 and rBet v 2) and plant
food allergens (apple, rMal d 1; celery, rApi g 1; and carrot, rDau c 1),
as well as natural pollen (birch and timothy grass) and plant food (apple,
peach, kiwi, hazelnut, celery, and carrot) allergens, to identify cross-rea
ctive allergens by using qualitative immunoblot inhibitions. In addition, w
e determined the percentage of plant food-specific IgE that can be preadsor
bed with recombinant and natural pollen allergens by quantitative RAST inhi
bitions by using sera from 71 patients with GAS.
Results: Preincubation of sera with recombinant and natural pollen allergen
s led to an almost complete inhibition of IgE binding to plant food allerge
ns in Western blots, as well as in RAST inhibition experiments. In contrast
, recombinant plant food allergens poorly inhibited IgE binding to Eet v 1.
Conclusion: Most IgE epitopes in plant food recognized by patients with OAS
are resembled by pollen allergens. Thus pollen allergens may be responsibl
e for the elicitation and maintenance of GAS.