IDENTIFICATION OF THE ALLERGEN PSI-C-2 FROM THE BASIDIOMYCETE PSILOCYBE-CUBENSIS AS A FUNGAL CYCLOPHILIN

Basidiospores are a prevalent and frequent cause of respiratory allerg ies, yet their allergens remain poorly defined; thus, we have attempte d a molecular characterization of representative basidiomycete allerge ns. A Psilocybe cubensis mycelial cDNA library was immunoscreened with patient serum. A clone was isolated that expressed a 23-kD recombinan t allergen as a fusion protein and inhibited a 16-kD band (Psi c 2) in immunoprints of P cubensis extract, indicating antigenic identity, Se quence (cDNA) analysis of the clone indicates homology with cyclophili n and the deduced amino acid sequence of Psi c 2 showed 78% identity a nd 4% similarity with the amino acid sequence of Schizosaccharomyces p ombe cyclophilin. This recombinant allergen is a useful model for epit ope analysis of basidiospore allergens and fungal allergen cross-react ivity, and may provide an improved reagent for basidiospore allergy di agnosis and treatment.