title: IgE reactivity pattern to timothy and birch pollen allergens in Finnish and Russian Karelia.
abstract: BACKGROUND
  Little is known about differences in IgE reactivity patterns to individual allergens in random populations. We studied the IgE reactivity profile to individual recombinant (r) and native (n) allergens in sera from subjects sensitized to timothy and/or birch pollen living in Finnish and Russian Karelia.
  
  
  METHODS
  Sera from IgE-sensitized adults were obtained from an epidemiological study on a random sample of 1,177 subjects. The IgE reactivity to pollen extracts and eight timothy (rPhl p 1, 2, 5, 6, 7, 11, 12 and nPhl p 4) and three birch pollen allergens (rBet v 1, 2 and 4) were analyzed with UniCAP.
  
  
  RESULTS
  The levels of IgE antibodies to timothy and birch pollen were higher in Finnish (median 5.2, range 0.35 to >100 kUA/l,) than in Russian Karelia (median 1.8 kUA/l, range 0.43-25.2 kUA/l, p <0.01). There was a significantly higher prevalence of IgE reactivity to three timothy pollen allergens in Finnish (n=57) than in Russian Karelia (n=12): rPhl p 2, 28 vs. 0%; rPhl p 5, 60 vs. 0%; rPhl p 6, 47 vs. 0%. The prevalence of IgE reactivity to the birch pollen allergens was similar in the two populations. IgE reactivity to rPhl p 2, 5, 6 and 11 was associated with hay fever symptoms. The timothy-pollen-specific serum IgE levels and the numbers of IgE reactivities to individual allergens correlated significantly (rs=0.87, p <0.0001).
  
  
  CONCLUSIONS
  The data indicate that timothy- and birch pollen-specific IgE levels are higher in Finnish compared to Russian Karelia. This is reflected in wider IgE reactivity to individual timothy pollen allergens in Finnish Karelia, including the major allergen Phl p 5, and increased pollen allergy.
authors.affiliation: Pharmacia Diagnostics AB and Uppsala University, Department of Medical Sciences, Respiratory Medicine and Allergology, Uppsala, Sweden. robert.moverare@diagnostics.com
authors.forename: Robert
authors.initials: R
authors.lastname: Movérare
authors.forename: Tuula
authors.initials: T
authors.lastname: Petays
authors.forename: Erkki
authors.initials: E
authors.lastname: Vartiainen
authors.forename: Tari
authors.initials: T
authors.lastname: Haahtela
mesh_terms: D000328:Adult; D000485:Allergens / Q000276:immunology*; D029662:Betula / Q000276:immunology*; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D031784:Phleum / Q000276:immunology*; D011058:Pollen / Q000276:immunology*; D012426:Russia / Q000453:epidemiology
chemical_list: D000485:Allergens; D007073:Immunoglobulin E