Immunoproteomic profile of Malus domestica in Mexican pediatric patients. Evidence of new allergen prospects

Abstract

Background: Apple (Malus domestica) is a fruit commonly associated with allergic oral symptoms in the Mexican pediatric population; however, knowledge of its allergenic proteins is limited. This information is crucial as sensitization frequencies to specific allergens can vary among different populations. The main allergic symptomatology before apple ingestion derives from primary sensitizations induced by pollen, promoting cross-reactivity with the main allergenic protein of apple. Therefore, this study aims to identify new potential sensitizing proteins to apple using immunoproteomic techniques. Methods: We collected serum samples from 14 pediatric patients with confirmed immunoglobulin E (IgE)-mediated apple allergy and used these samples to assess immunoreactivity to apple protein extracts through 2D-western blot assays. The spots corresponding to the 2D-SDS-PAGE were analyzed using nanoLC-MS/MS. Results: We identified 11 non-redundant proteins, including Mal d 2 and Mal d 1, the latter showing a high frequency of sensitization (79%) in our patients, and being considered the main apple allergenic protein. The remaining identified proteins have not been previously described as apple allergens in the International Union of Immunological Societies databases. However, three of these may be categorized as pan-allergens. Conclusions: This study shows evidence that the repertoire of apple allergens in the Mexican population could differ from those reported internationally, highlighting the importance of studies in different countries to improve the certainty of allergy diagnosis and allow the implementation of precision medicine.