Allergens of Curvularia lunata during cultivation in different media

Background: Despite enormous efforts toward the standardization of fungal e xtracts, only a few extracts have been characterized that are relevant for the diagnosis and immunotherapy of allergy-associated disorders. Objective: The goal of this study was to determine the optimum growth condi tion of Curvularia lunata, an important fungal allergen for quality raw mat erial, and to analyze the C lunata extract for IgE- and IgG-binding protein s. Methods: C lunata was grown in synthetic (Czapeck Dox medium), semisyntheti c (Sabouraud's broth [SB]), and natural media (potato dextrose [PD]) for di fferent periods of time. The extracts were probed for allergenic and antige nic activity, with pooled patient sera and polyclonal antibodies raised aga inst C lunata by means of ELISAs, immunoblots (in vitro), and intradermal t ests (in vivo). Results: The growth of C lunata was better in semisynthetic media (ie, SB) compared with other types of media. Dry weight and protein content was maxi mum in the 7-day culture of SE. ELISA with pooled sera from C lunata-sensit ive patients exhibited that cultures grown in SE for 11 to 13 days and PD p lus 1.0% agar for 5 days were the most potent. Intradermal tests with 11- t o 13-day SB culture extract showed maximum skin reactivity in allergy patie nts. Immunoblots with patient sera showed 10 to 14 IgE-binding proteins in 5- to 15-day SE cultures. Analysis of 5- to 15-day SE extract with rabbit s era showed 10 to 16 IgG-binding proteins. Conclusions: The extract from 11- to 13-day SE cultures were most biologica lly potent (intradermal tests) and showed high antigenic and allergenic rea ctivity (ELISA and immunoblot). The addition of yeast extract did not affec t the dry weight and protein content of the C lunata extract. Furthermore, addition of agar in PD medium increases the dry weight and protein content of the fungal mat. Synthetic media was not suitable for mass cultivation of C lunata.