title: Sensitization due to gum arabic (Acacia senegal): the cause of occupational allergic asthma or crossreaction to carbohydrates?
abstract: BACKGROUND
  A pharmaceutical industry worker was exposed to dust of gum arabic in the tablet coating plant and complained of work-related shortness of breath, chest tightness, runny nose, itching and redness of the eyes. This case was investigated for allergy to gum arabic and compared with a control group. The aim of the study was to identify the IgE-binding components responsible for the work-related symptoms.
  
  
  METHODS
  Skin prick tests (SPTs)and specific IgE (sIgE) measurements with environmental and occupational allergens, spirometry and a specific bronchial challenge with gum arabic were performed. One hundred and nineteen control subjects underwent SPT with gum arabic and 43 controls were tested for sIgE. Crossreactivity between gum arabic and horse radish peroxidase was investigated by IgE CAP inhibition. A combined procedure of immunoblotting and periodate treatment was applied to identify the epitope nature of gum arabic.
  
  
  RESULTS
  Allergy to gum arabic was shown by SPT, presence of sIgE and a positive bronchial challenge with gum arabic. Sensitization to gum arabic was demonstrated by SPT or sIgE in 7 and 5 controls, respectively. The results of inhibition with horse radish peroxidase, immunoblotting and periodate treatment suggest that gum arabic sIgE of the patient and 1 SPT-positive control subject were directed to the polypeptide chains of gum arabic. In contrast, gum arabic sIgE of the other controls reacted to carbohydrate components.
  
  
  CONCLUSIONS
  Sensitization to gum arabic carbohydrate structures occurs casually in atopic patients with pollen sensitization without obvious exposure to gum arabic. This study suggests that allergy to gum arabic is mediated preferentially by IgE antibodies directed to polypeptide chains of gum arabic.
authors.affiliation: Berufsgenossenschaftliches Forschungsinstitut für Arbeitsmedizin, Ruhr-Universität Bochum, Bochum, Deutschland. sander@bgfa.de
authors.forename: Ingrid
authors.initials: I
authors.lastname: Sander
authors.forename: Monika
authors.initials: M
authors.lastname: Raulf-Heimsoth
authors.forename: Kai
authors.initials: K
authors.lastname: Wiemer
authors.forename: Sabine
authors.initials: S
authors.lastname: Kespohl
authors.forename: Thomas
authors.initials: T
authors.lastname: Brüning
authors.forename: Rolf
authors.initials: R
authors.lastname: Merget
mesh_terms: D000328:Adult; D001249:Asthma / Q000097:blood / Q000139:chemically induced* / Q000276:immunology; D001985:Bronchial Provocation Tests; D002241:Carbohydrates / Q000276:immunology; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D006170:Gum Arabic / Q000009:adverse effects* / Q000737:chemistry; D006735:Horseradish Peroxidase / Q000276:immunology; D006801:Humans; D006967:Hypersensitivity / Q000097:blood / Q000209:etiology / Q000276:immunology; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D009784:Occupational Diseases / Q000097:blood / Q000139:chemically induced* / Q000276:immunology; D010455:Peptides / Q000276:immunology; D012882:Skin Tests
chemical_list: D002241:Carbohydrates; D010455:Peptides; D007073:Immunoglobulin E; D006170:Gum Arabic; D006735:Horseradish Peroxidase