title: Production profile of the major allergen Alt a 1 in Alternaria alternata cultures.
abstract: BACKGROUND
  The fungus Alternaria is strongly associated with asthma, but the importance of fungal allergen products is frequently underestimated. The profile of allergen release from fungal material is poorly understood.
  
  
  OBJECTIVE
  To investigate expression of the major allergen of Alternaria alternata, Alt a 1, during its growth in culture conditions for allergen extract production.
  
  
  METHODS
  Allergen expression was examined by Alt a 1-specific 2-site monoclonal antibody enzyme-linked immunosorbent assay, immunoblotting, and potency assays. The release of Alt a 1 was studied by transmission electron microscopy in conjunction with immunogold staining by using antibodies with specificity for Alt a 1.
  
  
  RESULTS
  A maximum amount of Alt a 1 was obtained after 4.5 weeks of growing, and it was found predominantly in the spent culture medium. In the same way, total IgE binding activity showed 15-fold more activity in the spent culture medium than in the buffer-extractable antigen fraction. Immunogold electron microscopy provided evidence that Alt a 1 is released from spores and mycelia.
  
  
  CONCLUSIONS
  Alternaria alternata allergenic proteins were constantly released into the culture medium, where they accumulated. Alt a 1 was a good marker for checking optimal culture conditions for A alternata extract production intended for clinical use.
authors.affiliation: Departamento de Investigación y Desarrollo, Bial-Arístegui, Bilbao, Spain.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Ibarrola
authors.forename: María
authors.initials: M
authors.lastname: Suárez-Cervera
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Arilla
authors.forename: Alberto
authors.initials: A
authors.lastname: Martínez
authors.forename: Javier
authors.initials: J
authors.lastname: Monteseirín
authors.forename: José
authors.initials: J
authors.lastname: Conde
authors.forename: Juan A
authors.initials: JA
authors.lastname: Asturias
mesh_terms: D000528:Alternaria / Q000276:immunology* / Q000648:ultrastructure*; D000818:Animals; D000946:Antigens, Fungal / Q000096:biosynthesis* / Q000276:immunology; D015153:Blotting, Western; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D007073:Immunoglobulin E / Q000276:immunology; D007150:Immunohistochemistry; D046529:Microscopy, Electron, Transmission; D013110:Sphingosine / Q000096:biosynthesis* / Q000276:immunology; D013172:Spores, Fungal / Q000276:immunology*
chemical_list: C047996:Alternaria alternata pathotoxin TA; D000946:Antigens, Fungal; D007073:Immunoglobulin E; D013110:Sphingosine