title: Sensitization to the pollen pan-allergen profilin. Is the detection of immunoglobulin E to multiple homologous proteins from different sources clinically useful?
abstract: BACKGROUND
  Profilin is a highly conserved protein regarded as a pan-allergen in pollen and vegetable food. Homologous proteins from different sources are highly cross-reactive.
  
  
  OBJECTIVE
  To assess whether detecting immunoglobulin (Ig) E to multiple profilins from different sources is clinically more useful than detecting IgE to a single representative profilin.
  
  
  METHODS
  Sera from 43 subjects sensitized to profilin selected in 2 allergy centers in Northern Italy showing a different pollen exposure profile were studied for their IgE reactivity to 5 profilins (Bet v 2, Ole e 2, Hev b 8, Mer a 1, and Phl p 12) using a commercial allergen microarray immunoassay.
  
  
  RESULTS
  All 43 patients (100%) scored positive to at least 1 profilin on ISAC, although reactivity to all 5 profilins was observed in only 37 cases (86%). In approximately half of the reactors, IgE reactivity to Ole e 2 was much weaker than that to other profilins irrespective of the primary sensitizing allergen source, suggesting a low sensitivity of this allergen. Much discrepancy in IgE to Bet v 2 measured by ISAC microarray and ImmunoCAP was observed.
  
  
  CONCLUSIONS
  Detecting IgE reactivity to a single marker protein (eg, Bet v 2) is sufficient to diagnose or exclude sensitization to profilin. Detecting IgE to multiple homologous, cross-reacting allergen proteins is not clinically more informative and increases the risk of confusion and misinterpretation.
authors.affiliation: Allergologia e Immunologia Clinica, Dipartimento di Medicina di Laboratorio, A.O. "S. Maria degli Angeli", Pordenone, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Villalta
authors.forename: R
authors.initials: R
authors.lastname: Asero
mesh_terms: D000485:Allergens / Q000276:immunology*; D003429:Cross Reactions; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000097:blood / Q000175:diagnosis / Q000276:immunology*; D007118:Immunoassay / Q000379:methods; D007073:Immunoglobulin E / Q000097:blood*; D011058:Pollen / Q000276:immunology*; D051304:Profilins / Q000276:immunology*; D040081:Protein Array Analysis
chemical_list: D000485:Allergens; D051304:Profilins; D007073:Immunoglobulin E