Plant Microfungi Tranzschelia pruni-spinosae and Phragmidium rubi-idaei Demonstrate Allergenic Capabilities in Mouse Models of Asthma

Allergic conditions have surged to unprecedented levels globally, affecting approximately 30% of the global population. Fungi are among the most significant sources of allergens, accounting for approximately 6% of respiratory issues in the general population. However, identifying the precise cause of respiratory allergies remains challenging. We investigated the potential of two rust species, <i>Tranzschelia pruni-spinosae</i> and <i>Phragmidium rubi-idaei</i>, which infect common fruit plants, to induce inflammatory and asthmatic responses in mouse models of both acute and chronic asthma. Mice were sensitized and administered intranasal challenges with extracts from <i>T. pruni-spinosae</i> and <i>P. rubi-idaei</i>. Levels of pro-inflammatory cytokines (IL-4, IL-5, IL-13, TNF-α, and TGF-β) were measured via ELISA. Additionally, specific IgE production was assessed via ELISA and lung histology was examined using hematoxylin-eosin staining. Both fungal extracts induced significant increases in all tested cytokines, elevated specific IgE levels, and histological changes characteristic of acute and chronic asthma progression in the lungs. The microfungi <i>T. pruni-spinosae</i> and <i>P. rubi-idaei</i> possess strong proinflammatory and asthma-inducing capabilities, suggesting their potential as previously unrecognized fungal allergens.