Birch pollen-related food allergy: clinical aspects and the role of allergen-specific IgE and IgG4 antibodies

J Allergy Clin Immunol. 2011 Mar;127(3):616-22.e1. doi: 10.1016/j.jaci.2010.10.027. Epub 2011 Jan 20.


Background: Patients with birch pollen allergy often develop allergic reactions to plant foods.

Objective: To evaluate the prevalence, main symptoms, and triggers of birch pollen-related food allergy and the role of food-specific IgG(4) antibodies in food tolerance.

Methods: Food-induced symptoms were evaluated in 225 individuals with birch pollen allergy by using a standardized questionnaire. IgE and IgG(4) levels specific for the major birch pollen allergen Bet v 1 and birch profilin Bet v 2 and the Bet v 1 homologs in apple (Mal d 1) and hazelnut (Cor a 1) were quantified by ImmunoCAP. Mock-treated and IgG-depleted sera from patients tolerating hazelnuts in food challenges were compared for their inhibitory activity for binding of Cor a 1-IgE complexes to B cells.

Results: In total, 73% of the study population experienced food allergy, which was perennial in 86% of the affected individuals. The oral allergy syndrome was the main clinical manifestation. However, more than 58% of the patients also experienced food-induced rhinoconjunctivitis. Apples and hazelnuts were identified as the most frequent triggers. Food allergy correlated with IgE reactivity to Bet v 1 but not to Bet v 2. Mal d 1-specific and Cor a 1-specific IgG(4)/IgE ratios were significantly higher in food-tolerant individuals than individuals with food allergy. Sera from IgG(4)-positive food-tolerant patients possessed IgG-dependent IgE-inhibitory activity.

Conclusion: Birch pollen-related food allergy is highly prevalent and often perennial. High food allergen-specific IgG(4)/IgE ratios seem associated with food tolerance, potentially because specific IgG(4) blocks IgE binding to food allergens. Thus, the presence of food allergen-specific IgG(4) antibodies is no diagnostic marker for birch pollen-related food allergy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Antigens, Plant / classification
  • Antigens, Plant / immunology*
  • Betula / immunology*
  • Child
  • Female
  • Food Hypersensitivity / immunology*
  • Humans
  • Immunoglobulin E / blood
  • Immunoglobulin E / immunology*
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology*
  • Male
  • Middle Aged
  • Pollen / immunology*
  • Surveys and Questionnaires


  • Antigens, Plant
  • Immunoglobulin G
  • Immunoglobulin E