Volume 3 Supplement 3
Hypoallergenic allergen derivatives of Pru p 3 for immunotherapy of IgE-mediated peach allergy
© Linhart et al; licensee BioMed Central Ltd. 2013
Published: 25 July 2013
IgE-mediated allergy to peach represents a frequent cause of severe anaphylactic reactions in Mediterranean countries. Pru p 3, a nonspecific lipid transfer protein (LTP) from peach, was identified as an important elicitor of IgE-mediated food hypersensitivity reactions to peach. Specific immunotherapy is currently the only allergen-specific and disease-modifying treatment of allergies, but has so far not been applied to food allergic patients due to the high risk of IgE-mediated side effects. Hypoallergenic Pru p 3 derivatives have therefore been constructed in order to minimize side-effects, but these molecules were not immunogenic in animal models.
Two recombinant Pru p 3-derivatives were developed based on the Pru p 3 amino acid sequence, by introduction of point mutations, or rearrangements of Pru p 3 fragments and oligomerization. Genes encoding the resulting Pru p 3 derivatives were cloned into the expression vector pET27b and expressed in Escherichia coli. The proteins were purified by affinity chromatography and analyzed by SDS-PAGE and mass spectrometry. IgE-reactivity was tested by dot blot analysis and immunogenicity was investigated by immunization of rabbits.
Expression of the two recombinant Pru p 3 derivatives in Escherichia coli yielded high amounts of recombinant proteins. They were purified to homogeneity and exhibited a strongly reduced IgE-reactivity when exposed to sera of peach allergic patients. Upon immunization of rabbits the Pru p 3 derivatives induced a robust IgG antibody response specific for natural Pru p 3.
The reported recombinant hypoallergenic Pru p 3 derivatives are candidates for specific immunotherapy of peach allergic patients.
Disclosure of interest
B Linhart: None declared, A Gstoettner: None declared, C Gamez: None declared, I Swoboda: None declared, A Mari: None declared, N Papadopoulos: None declared, R Valenta: Grant/research support from Biomay AG, Vienna, Austria.
This work was supported by a research grant from Biomay AG, Vienna, Austria.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.