Respiratory allergy to Aspergillus-derived enzymes in bakers' asthma

J Allergy Clin Immunol. 1992 Dec;90(6 Pt 1):970-8. doi: 10.1016/0091-6749(92)90470-m.


Baking and food industry workers are exposed to several powdered Aspergillus-derived enzymes with carbohydrate-cleaving activity that are commonly used to enhance baked products. We describe a retrospective study of sensitization to fungal alpha-amylase and cellulase on bakers. Five bakers in whom respiratory allergy symptoms developed when they were exposed to bread "improvers" that contained fungal alpha-amylase and cellulase were investigated by in vivo and in vitro tests. Type I hypersensitivity to these enzymes was demonstrated in the five patients by means of skin testing, histamine release test, positive reverse enzyme-immunoassay for specific IgE antibodies, and bronchial provocation test response to alpha-amylase or cellulase or both. Isolated immediate and dual responses to the bronchial challenge tests with these enzymes were observed. Immunoblot analysis with use of a pooled serum identified IgE-binding components in both enzymes. In the reverse-enzyme immunoassay-inhibition assays cross-reactivity between alpha-amylase and cellulase was not found, but some degree of cross-reactivity between alpha-amylase and A. oryzae, and between cellulase and A. niger was demonstrated. Four of the patients were also sensitized to cereal flour. Aspergillus-derived enzymes used as flour additives can elicit IgE-mediated respiratory allergy, and this fact has to be considered in the diagnosis and clinical management of bakers' asthma.

Publication types

  • Case Reports
  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Allergens / adverse effects
  • Allergens / immunology
  • Amylases / immunology
  • Aspergillus / enzymology*
  • Asthma / immunology*
  • Bronchial Provocation Tests
  • Cellulase / immunology
  • Electrophoresis, Polyacrylamide Gel
  • Female
  • Food Additives / adverse effects
  • Histamine Release
  • Humans
  • Immunoblotting
  • Immunoenzyme Techniques
  • Immunoglobulin E / analysis
  • Male
  • Middle Aged
  • Occupational Diseases / etiology*
  • Respiratory Hypersensitivity / etiology*
  • Skin Tests
  • Sodium Dodecyl Sulfate


  • Allergens
  • Food Additives
  • Sodium Dodecyl Sulfate
  • Immunoglobulin E
  • Amylases
  • Cellulase