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Dictionary of Allergies .. Mimotopes

Mimotopes

Mimotopes are peptides mimicking protein, carbohydrates or lipid epitopes and can be generated by phage display technology[1]. Mimotopes are mimicking natural epitopes in the structural as well as in the immunological point of view. They are able to induce antigen-specific antibodies in active immunization form. These antibodies are directed against the natural antigen/allergen, and therefore they are able to block the outbreak of the diseases[3] The induction of nonanaphylactogenic 'blocking' IgG antibodies capable of inhibiting the IgE/allergen interaction represents a favorable therapeutic concept for type I allergy. However, IgG antibodies to allergens may block or enhance specific IgE binding, depending on the recognized epitope. When selected by antibodies, they represent exclusively B-cell epitopes and are devoid of antigen/allergen-specific T-cell epitopes. Coupled to carriers or presented in a multiple antigenic peptide form mimotopes achieve immunogenicity and induce epitope-specific antibody responses upon vaccination. Τhe mimotope concept is applicable to both fields for epitope-specific vaccination and analysis of conformational B-cell epitopes for the allergen/antigen. In allergy IgG antibodies may block IgE binding to allergens, whereas other IgG antibody specificities enhance this and support the anaphylactic reaction. In cancer, inhibitory antibody specificities prevent growth signals derived from overexpressed oncogenes, whereas growth-promoting specificities enhance signalling and proliferation[1]. Allergen mimotopes can be used for the induction of anti allergen IgG of desired specificity[2]. Mimotope technology is a relatively young theme in allergology and oncology. Still, proof of concept studies testing allergen and tumour mimotope vaccines suggest that mimotopes are ready for clinical trials.


References

1. Knittelfelder R, Riemer AB, Jensen-Jarolim E. Mimotope vaccination - from allergy to cancer. Expert Opin Biol Ther. 2009 Apr;9(4):493-506.

2. Ganglberger E, Grünberger K, Wiedermann U, Vermes M, Sponer B, Breiteneder H, Scheiner O, Boltz G, Jensen-Jarolim E. IgE mimotopes of birch pollen allergen Bet v 1 induce blocking IgG in mice. Int Arch Allergy Immunol. 2001 Jan-Mar;124(1-3):395-7.

3. Szalai K, Jensen-Jarolim E, Pali-Schöll I. Vaccination strategies based on the mimotope concept. G Ital Dermatol Venereol. 2008 Apr;143(2):95-104

Γκέλης Ν.Δ. - Λεξικό Αλλεργίας - Εκδόσεις ΒΕΛΛΕΡOΦΟΝΤΗΣ - Κόρινθος 2013

Gelis Ν.D. - Dictionary of Allergies - VELLEROFONTIS Publications - Corinth 2013