Occurrences of allergenicity to banana pathogenesis-related-10 (PR10) protein variants

Abstract

Pathogenesis-related-10 (PR10) proteins play significant roles in plant defence against biotic and abiotic stresses. Recently, two banana PR10 proteins (MaPR10-BeB5 and MaPR10-GNA5) were characterised and shown to exhibit antifungal properties against Aspergillus fumigatus in vitro. In rice, transgenic overexpression of PR10 proteins conferred resistance to pathogen infection and drought tolerance without affecting productivity, highlighting their potential for agricultural applications. However, PR10 proteins also include the Bet v 1-like family of allergens implicated in pollen food allergy syndromes, raising concerns about potential adverse effects on human health. In this study, we evaluated the allergenic potential of the recently isolated banana PR10 proteins. We first predicted the presence of IgE epitopes of the Bet v 1 allergen family in the deduced PR10 peptide sequences in silico. We then predicted the structures of four human IgE scFv protein sequences and three plant PR10 protein sequences. Based on the quality of the predicted structures, one IgE scFv protein structure was selected for docking with the three plant PR10 proteins. We confirmed the docking results with immunoblot analysis performed using recombinant MaPR10-BeB5 and MaPR10-GNA5 proteins against the sera of banana-allergic patients. Our experimental results substantiated the notion that both protein variants are potentially allergenic since these proteins were recognised by 26.6% of banana-allergic patients with broad PR10 protein recognition. We caution that the allergenic potential of MaPR10 proteins should be carefully considered before implementing transgenic overexpression strategies to improve crops, with a suggestion to limit their expression to non-edible plant tissues.