ISOLATION AND IMMUNOBIOCHEMICAL CHARACTERIZATION OF A MAJOR ALLERGEN (65 KDA) FROM FUSARIUM-EQUISETI

Fusarium equiseti is one of the most important species in the class De uteromycetes (Fungi Imperfecti). For proper diagnosis and immunotherap y, isolation and characterization of allergens of F. equiseti are nece ssary. In the present study, culture filtrate (CF) extract of F. equis eti was resolved into 35-37 bands on isoelectric focusing pi (3-9) and SDS-PAGE (mel. wt. 10-100 kDa). Most of them were glycoproteins, as i dentified by PAS staining. F. equiseti CF revealed 15 allergenic prote ins on immunoblot with an allergic serum pool. It was fractionated int o nine fractions (I-IX) on a Superose-12 column by FPLC. Fraction IV ( 65 kDa) and fraction VI (25 kDa) were found to be highly allergenic by IgE ELISA. A 65-kDa protein was observed as a major allergen because it was recognized by most of the patient sera on immunoblot. After elu tion from SDS-PAGE gel, it gave two bands of pi 7.4 and 6.0. Inhibitio n in IgE-binding components of F. equiseti CF with CF extracts of F. s olani and F. moniliforme by immunoprint inhibition assay indicated the allergenicity shared between the extracts of Fusarium species. Data s uggested that the 65-kDa is the major allergen in the Fusarium species and can be used for the treatment of allergic patients.