title: Nondiffusional release of allergens from pollen grains of Artemisia vulgaris and Lilium longiflorum depends mainly on the type of the allergen.
abstract: BACKGROUND
  Upon contact with a wet surface, mature pollen grains hydrate and release proteins including allergens. Knowledge of the release mechanism of allergens that are mainly localized intracellularly may allow the design of strategies for inhibition of allergen release and the consequent sensitization process.
  
  
  METHODS
  An improved pollen chromatography was performed with Artemisia vulgaris and Lilium longiflorum pollen. Using three elution media of different pH, osmolality and salt concentration mimicking various types of wet surfaces, the time-dependent elution profiles of total protein, a cell wall-bound acid phosphatase activity (acPase), allergenic (profilin, Art v 1) and nonallergenic molecules (14-3-3 protein, actin) were monitored.
  
  
  RESULTS
  The release kinetics of total protein and cell wall-bound acPase followed an exponential decrease in both pollen species indicating a diffusion-based protein release, whereas the elution profiles of profilin, Art v 1 and 14-3-3 protein showed nondiffusion characteristics. No general dependence on pH, osmolality or salt concentration of the elution media was observable in the elution profiles. Under the applied conditions, actin was not released indicating that the pollen grains remained intact during the elution.
  
  
  CONCLUSIONS
  The elution profiles of pollen allergens indicated that substantial amounts of these proteins do not diffuse from the cell wall or are released from intracellular compartments during imbibitional leakage. Instead, a mechanism seems to operate that involves translocation from the pollen cytoplasm to the extracellular environment by crossing an intact plasma membrane. Such a mechanism would probably allow the use of pharmaceuticals for inhibition of allergen release.
authors.affiliation: Molecular Plant Physiology Group, Department of Molecular Biology, Division of Allergy and Immunology, University of Salzburg, Salzburg, Austria.
authors.forename: Claudia
authors.initials: C
authors.lastname: Hoidn
authors.forename: Erika
authors.initials: E
authors.lastname: Puchner
authors.forename: Heidi
authors.initials: H
authors.lastname: Pertl
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Holztrattner
authors.forename: Gerhard
authors.initials: G
authors.lastname: Obermeyer
mesh_terms: D048948:14-3-3 Proteins / Q000737:chemistry / Q000276:immunology*; D000135:Acid Phosphatase / Q000737:chemistry / Q000276:immunology; D000485:Allergens / Q000737:chemistry / Q000276:immunology*; D052179:Antigens, Plant; D019306:Artemisia / Q000737:chemistry / Q000276:immunology*; D002845:Chromatography; D003285:Contractile Proteins / Q000737:chemistry / Q000276:immunology*; D004591:Electrophoresis, Polyacrylamide Gel; D015151:Immunoblotting; D007700:Kinetics; D027762:Lilium / Q000737:chemistry / Q000276:immunology*; D008840:Microfilament Proteins / Q000737:chemistry / Q000276:immunology*; D010940:Plant Proteins / Q000737:chemistry / Q000276:immunology*; D011058:Pollen / Q000737:chemistry / Q000276:immunology*; D051304:Profilins
chemical_list: D048948:14-3-3 Proteins; D000485:Allergens; D052179:Antigens, Plant; C102724:Art v 1 protein, mugwort; D003285:Contractile Proteins; D008840:Microfilament Proteins; D010940:Plant Proteins; D051304:Profilins; D000135:Acid Phosphatase