title: Comparison of enzyme immunoassay-based assays for environmental Alternaria alternata.
abstract: BACKGROUND
  Alternaria alternata-derived allergenic materials are causes of human disease. Several immunoassays exist to quantify these materials.
  
  
  OBJECTIVE
  To compare methods for evaluating Alternaria content.
  
  
  METHODS
  Four methods, including 1 monoclonal antibody (MAb)-based assay specific for recombinant Alt a 1, 1 MAb-based assay for chromatographically purified Alt a 1, 1 polyclonal antibody (PAb)-based assay for chromatographically purified Alt a 1, and 1 PAb-based assay for whole Alternaria extract, were evaluated. Environmental samples collected as part of the National Survey of Lead and Allergens in Housing were examined. Alternaria spore counts were determined in dust by observation.
  
  
  RESULTS
  The MAb-based assay for recombinant Alt a 1 detected Alternaria in few samples (25%); the PAb-based assay for whole Alternaria proteins detected antigen in 97% of the samples. The PAb- and MAb-based assays for purified Alt a 1 detected antigen in 100% of the samples. There was a significant positive correlation between the 2 assays directed against purified Alt a 1. There was a positive correlation between the PAb-based assay for whole Alternaria and the PAb-based assay for Alt a 1. Nearly all the dust samples contained Alternaria spores, and there was a strong positive correlation between counts and all assays.
  
  
  CONCLUSIONS
  Because of the multifaceted nature of Alternaria, the disparities between methods for quantifying Alternaria, the cross-reactivity between fungal allergens, and the documented genetic promiscuity of this fungus, enzyme immunoassays using PAbs against a range of Alternaria proteins will probably produce the most reliable estimation of overall Alternaria exposure in house dust.
authors.affiliation: Allergy/Asthma/Immunology, Children's Mercy Hospital, Kansas City, Missouri 64108, USA. cbarnes@cmh.edu
authors.forename: Charles
authors.initials: C
authors.lastname: Barnes
authors.forename: Jay
authors.initials: J
authors.lastname: Portnoy
authors.forename: Michelle
authors.initials: M
authors.lastname: Sever
authors.forename: Samuel
authors.initials: S
authors.lastname: Arbes
authors.forename: Ben
authors.initials: B
authors.lastname: Vaughn
authors.forename: Darryl C
authors.initials: DC
authors.lastname: Zeldin
mesh_terms: D000393:Air Pollutants / Q000276:immunology / Q000302:isolation & purification*; D000485:Allergens / Q000276:immunology / Q000302:isolation & purification*; D000528:Alternaria / Q000276:immunology / Q000302:isolation & purification*; D000911:Antibodies, Monoclonal / Q000276:immunology; D000946:Antigens, Fungal / Q000276:immunology; D003429:Cross Reactions; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods*; D013170:Spores / Q000276:immunology / Q000302:isolation & purification*
chemical_list: D000393:Air Pollutants; D000485:Allergens; D000911:Antibodies, Monoclonal; D000946:Antigens, Fungal