title: Characterization of immunoglobulin E responses in Balb/c mice against the major allergens of timothy grass (Phleum pratense) pollen.
abstract: BACKGROUND
  Grass pollen, such as that from timothy grass (Phleum pratense), represents a major cause of type I allergy.
  
  
  OBJECTIVE
  To characterize the IgE immune response and to identify the major allergens eliciting an IgE response in a mouse model using pollen extract of P. pratense for sensitization, in order to assess analogies to human hyperreactivity and to gain information on the allergenic potential as determined by the IgE-reactivity kinetics of defined allergens.
  
  
  METHODS
  Balb/c mice were sensitized with pollen extract or with purified natural allergens. Serum IgE levels, the induction of specific IgE antibodies and immediate hypersensitivity were monitored by ELISA, Western blot and a skin test, respectively.
  
  
  RESULTS
  The sensitized mice mounted a strong IgE response and showed IgE-reactivity first against Phl p 5a and 5b, then Phl p 4 and 13 and lastly against Phl p 6. No IgE response was mounted against Phl p 1. However, all purified fractions examined (Phl p 5a, 5b, 6 and 1) induced specific IgE and showed similar kinetics of IgE induction as pollen extract (first Phl p 5a and 5b, then Phl p 6). Skin test experiments demonstrated positive reactivity only in sensitized mice.
  
  
  CONCLUSIONS
  The IgE reactivity induced by the major allergens in Balb/c mice was very similar to that found in allergic patients, with the exception of Phl p 1. The kinetics of the specific IgE response was comparable using either pollen extract or the purified major allergens, indicating that the intrinsic properties of the allergens are of importance rather than their proportionate amounts in pollen extract. This model should prove to be suitable for investigations regarding the mechanisms of induction and manifestation of timothy grass pollen allergy and for the evaluation of therapeutic strategies.
authors.affiliation: Divisions of Veterinary Infectiology and Immunology and Biochemical and Molecular Allergy, Research Center Borstel, Borstel, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Seitzer
authors.forename: H
authors.initials: H
authors.lastname: Bussler
authors.forename: B
authors.initials: B
authors.lastname: Kullmann
authors.forename: A
authors.initials: A
authors.lastname: Petersen
authors.forename: W-M
authors.initials: WM
authors.lastname: Becker
authors.forename: J
authors.initials: J
authors.lastname: Ahmed
mesh_terms: D000485:Allergens / Q000276:immunology*; D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D017449:Dermatitis, Allergic Contact / Q000276:immunology; D004195:Disease Models, Animal; D005260:Female; D007073:Immunoglobulin E / Q000096:biosynthesis*; D051379:Mice; D008807:Mice, Inbred BALB C; D031784:Phleum / Q000276:immunology*; D010940:Plant Proteins / Q000276:immunology; D011058:Pollen / Q000276:immunology*
chemical_list: D000485:Allergens; C095238:PHLPVI protein, Phleum pratense; C100980:Phl p 4 protein, Phleum pratense; C076049:Phl p V protein, Phleum pratense; D010940:Plant Proteins; D007073:Immunoglobulin E