Nowadays, treatment of food allergy only considered the avoidance of the specific food. However, the possibility of cross-reactivity makes this practice not very effective. Immunotherapy may exhibit as a good alternative to food allergy treatment. The use of hypoallergenic molecules with reduced IgE binding capacity but with ability to stimulate the immune system is a promising tool which could be developed for immunotherapy. In this study, three mutants of Pru p 3, the principal allergen of peach, were produced based on the described mimotope and T cell epitopes, by changing the specific residues to alanine, named asPru p 3.01, Pru p 3.02, andPru p 3.03.Pru p 3.01showed very similar allergenic activity as the wild type byin vitroassays. However,Pru p 3.02andPru p 3.03presented reduced IgE binding with respect to the native form, byin vitro,ex vivo,and in vivo assays. In addition,Pru p 3.03had affected the IgG4 binding capacity and presented a random circular dichroism, which was reflected in the nonrecognition by specific antibodies anti-Pru p 3. Nevertheless, bothPru p 3.02andPru p 3.03maintained the binding to IgG1 and their ability to activate T lymphocytes. Thus,Pru p 3.02andPru p 3.03could be good candidates for potential immunotherapy in peach-allergic patients.
Molecular basis of pollen-related food allergy: identification of a second cross-reactive IgE epitope on Pru av 1, the major cherry (Prunus avium) allergen