Studies on shared antigenic/allergenic components among fungi

Fungal allergens have been found to be one of the most prevalent aeroallergens in India. Knowledge of shared/unique components among different fungi is necessary for proper diagnosis and treatment of patients allergic to fungi. In the present study, crude extracts (CE) of 11 common fungi (Alternaria alternata, Aspergillus flavus, Asp. fumigatus, Asp. niger, Asp. tamarii, Asp. versicolor, Cladosporium herbarum, Curvularia lunata, Mucor hiemalis, Penicillium citrinum, and Fusarium solani) were characterized by isoelectric focusing (IEF), SDS-PAGE, and immunoblot. On IEF (pI 3-9), the number of protein bands was found to be greatest (46) in M. hiemalis extract. SDS-PAGE exhibited a varied number of bands, generally 18-40, with mol. mass ranging from 14 to 100 kDa. IgG-specific immunoprint using rabbit anti-F. solani CF antibodies demonstrated a mol. mass distribution of shared antigenic proteins of 14-100 kDa in most of the fungi. Shared allergenicity was observed in a number of allergenic proteins in fungal extracts with mol. mass ranging between 14 and 70 kDa on IgE-specific immunoblot using pooled sera of patients allergic to Fusarium. A 45-kDa protein was found to be common among these fungi on immunoblot with patients as well as with rabbit antibodies. F. solani CF extract contained more antigenic/allergenic proteins than F. solani CE. It was concluded that F. solani CF shared several antigenic/allergenic components with CE of other common fungi. This fact needs to be taken into account when fungal extracts are used in diagnosis and immunotherapy of allergic patients.