Microfungus Podosphaera fusca and the Fungus-like Organism Peronospora ficariae as Potential Inhalant Allergens in a Mouse Model of Asthma.

Allergic conditions have surged to unprecedented levels globally, affecting approximately 30% of the population. Fungi are among the major sources of allergens, accounting for about 6% of respiratory issues. Identifying the causes of respiratory allergies is not always possible. Our study assessed the capacity of two plant parasites, Podosphaera fusca and Peronospora ficariae, which infect Cucurbita pepo and Ficaria verna, to provoke inflammatory and asthmatic reactions in mouse models of acute and chronic asthma. We performed experiments by sensitizing mice through intranasal challenges with extracts from P. fusca and P. ficariae. Subsequently, we used ELISA tests to measure pro-inflammatory cytokines, including IL-4, IL-5, IL-13, TNF-α, and TGF-β. We evaluated specific IgE production through ELISA and examined histological changes in mouse lungs using hematoxylin-eosin staining. Our research revealed that P. fusca and P. ficariae induced significant production of all tested cytokines, increased specific IgE levels, and caused histological changes characteristic of acute and chronic asthma progression. Although weaker than the reference allergen ovalbumin, P. fusca and P. ficariae possess proinflammatory and asthma-inducing capabilities, indicating the potential to expand the current list of fungal allergens.