title: Sensitization to timothy grass pollen allergenic molecules in children.
abstract: BACKGROUND
  Grass pollens are significant elicitors of IgE-mediated allergic disease in the world and timothy (Phleum pratense) is one of the most important pollens of the family. Molecular and biochemical characterization of Phleum pratense has revealed several allergen components: rPhl p 1 and rPhl p 5 have been shown to be "Species Specific Allergens", while the profilin rPhl p 12 and the calcium-binding protein rPhl p 7 are the principal Cross-Reactive components.
  
  
  METHODS
  In this study the pattern of sensitization to rPhl p 1, rPhl p 5, rPhl p 7 and rPhl p 12 was analyzed in children with asthma and/or rhinoconjunctivitis and grass pollen allergy, in order to evaluate the frequency of sensitization to allergenic molecules of Phleum pratense among pediatric subjects allergic to grass pollen in a Mediterranean population. The correlation of sensitization to these Phleum allergenic molecules with IgE against grass pollen extract and its variation according to age and level of IgE against grass pollen extract were evaluated.
  
  
  RESULTS
  IgE against to rPhl p 1 were found in 99% (205/207) of patients, to rPhl p 5 in 67% (139/207), to rPhl p 12 in 32% (66/207) and to rPhl p 7 only in 5% (10/207).Sensitization only to "Species Specific" (rPhl p1, rPhl p5) allergenic molecules of Phleum pratense was detected in 65% (135/207) of children. Our data show the predominant role of rPhl p 1 in pediatric populations as the most relevant sensitizing allergen detectable at all ages and at all levels of timothy grass pollen-specific IgE antibodies, while the importance of rPhl p 5 rises with the increase of patients' age and with grass pollen IgE levels.
  
  
  CONCLUSIONS
  The assessment of sensitization to grass pollen allergenic molecules could help develop a better characterization of allergic sensitization in grass pollen allergy in children, which may be different in every patient. It could also enable clinicians to give more specific and effective immunotherapy, based on allergenic molecule sensitization.
authors: Department of Pediatrics, University of Chieti, Via Dei Vestini 5, 66100, Chieti, Italy. ale.scaparrotta@libero.it.
authors: Alessandra
authors: A
authors: Scaparrotta
authors: Marcello
authors: M
authors: Verini
authors: Nicola Pietro
authors: NP
authors: Consilvio
authors: Anna
authors: A
authors: Cingolani
authors: Daniele
authors: D
authors: Rapino
authors: Marina
authors: M
authors: Attanasi
authors: Marzia
authors: M
authors: Cerasa
authors: Sabrina
authors: S
authors: Di Pillo
authors: Francesco
authors: F
authors: Chiarelli