Skin test evaluation of genetically engineered hypoallergenic derivatives of the major birch pollen allergen, Bet v 1: results obtained with a mix of two recombinant Bet v 1 fragments and recombinant Bet v 1 trimer in a Swedish population before the birch pollen season

J Allergy Clin Immunol. 1999 Nov;104(5):969-77. doi: 10.1016/s0091-6749(99)70077-1.


Background: More than 95% of birch pollen-allergic subjects react with the major birch pollen allergen, Bet v 1, and almost 60% of them are sensitized exclusively to this allergen.

Objective: The aim of this study was to compare the in vivo biologic activity of genetically engineered hypoallergenic derivatives of Bet v 1 (an equimolar mixture of 2 recombinant [r] Bet v 1 fragments and of rBet v 1 trimer) with that of rBet v 1 wild-type by skin prick and intradermal testing.

Methods: Birch pollen-allergic patients who had not received immunotherapy (n = 23), a group of allergic patients without birch pollen allergy (n = 12), and nonatopic persons (n = 8) from northern Europe (Sweden) underwent skin prick and intradermal testing with different concentrations of the recombinant allergens and commercial birch pollen extract before the birch pollen season. Immediate and late-phase reactions were recorded and allergen-specific IgE and IgG subclass responses were determined by CAP radioallergosorbent test and ELISA, respectively.

Results: Atopic persons without birch pollen allergy and nonatopic individuals did not have skin reactions to rBet v 1 wild-type and genetically engineered hypoallergenic derivatives. By intradermal testing, 8 of 23 and 13 of 23 birch pollen-allergic patients did not react with the highest concentration (1 microg/mL) of the rBet v 1 fragment mix and rBet v 1 trimer, respectively, compared with 1 with rBet v 1 wild type. Likewise, the highest concentration (100 microg/mL) of fragment mix or trimer failed to elicit a positive skin prick test in 18 of 23 and 15 of 23 patients in comparison with 0/23 with the monomer. No late reactions were observed.

Conclusion: The recombinant hypoallergenic birch pollen allergens can probably be used for patient-tailored immunotherapy with a reduced risk to induce anaphylactic reactions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Allergens / immunology*
  • Antigens, Plant
  • Asthma / blood
  • Asthma / immunology*
  • Conjunctivitis, Allergic / blood
  • Conjunctivitis, Allergic / immunology*
  • Evaluation Studies as Topic
  • Female
  • Genetic Engineering
  • Humans
  • Immunoglobulin E / blood
  • Immunoglobulin G / blood
  • Immunoglobulins / blood
  • Intradermal Tests
  • Male
  • Middle Aged
  • Peptide Fragments / immunology
  • Plant Proteins / immunology*
  • Pollen / immunology*
  • Recombinant Fusion Proteins / immunology
  • Seasons
  • Skin Tests
  • Sweden
  • Trees


  • Allergens
  • Antigens, Plant
  • Immunoglobulin G
  • Immunoglobulins
  • Peptide Fragments
  • Plant Proteins
  • Recombinant Fusion Proteins
  • Bet v 1 allergen, Betula
  • Immunoglobulin E