Characterization of the protective and therapeutic efficiency of a DNA vaccine encoding the major birch pollen allergen Bet v 1a
Article first published online: 12 DEC 2003
Volume 59, Issue 1, pages 65–73, January 2004
How to Cite
Hartl, A., Hochreiter, R., Stepanoska, T., Ferreira, F. and Thalhamer, J. (2004), Characterization of the protective and therapeutic efficiency of a DNA vaccine encoding the major birch pollen allergen Bet v 1a. Allergy, 59: 65–73. doi: 10.1046/j.1398-9995.2003.00335.x
- Issue published online: 12 DEC 2003
- Article first published online: 12 DEC 2003
- Accepted for publication 23 June 2003
- Bet v 1a;
- DNA vaccines;
- gene vaccines;
- Th1/Th2 cells
Background: An estimated 100 million individuals suffer from birch pollen allergy. More than 95% of birch pollen-allergic subjects react with the major birch pollen allergen Bet v 1a, and almost 60% of them are sensitized exclusively to this allergen.
Objective: DNA immunization using the Bet v 1a gene was evaluated with respect to its prophylactic and therapeutic efficacy.
Methods: A DNA vaccine containing the entire Bet v 1a cDNA under the control of a CMV-promoter was constructed. In order to estimate the protective efficiency, animals received three injections of this vaccine prior to sensitization with recombinant Bet v 1a. Vice versa, in a therapeutic approach, sensitization was followed by treatment with the DNA vaccine.
Results: The Bet v 1a DNA vaccine induced strong Bet v 1-specific antibody responses with a Th1-biased response type. Animals which received the DNA vaccine were protected against a following allergic sensitization with Bet v 1a. The protective effect was characterized by suppression of Bet v 1-specific immunoglobulin (Ig)E production, lack of basophil activation and enhanced interferon (IFN)-γ expression. In a therapeutic situation, treatment of sensitized animals with DNA vaccines decreased IgE production, IgE-mediated basophil release and drastically reduced anaphylactic activity as measured by passive cutaneous anaphylaxis assays. Concerning the cellular immune response, DNA immunization induced a sustaining and dominant shift from a Th2 type response towards a balanced Th1/Th2 type response as indicated by increased IFN-γ but unchanged IL-5 levels in lymphoproliferation assays.
Conclusion: The results demonstrate the allergen-specific protective and therapeutic efficacy of a DNA vaccine encoding the clinically highly relevant allergen Bet v 1a indicating the suitability of this concept for the treatment of allergic diseases.