Characterization of the dog lipocalin allergen Can f 6: the role in cross-reactivity with cat and horse

Allergy. 2012 Jun;67(6):751-7. doi: 10.1111/j.1398-9995.2012.02826.x. Epub 2012 Apr 20.


Background: Allergy to the domestic dog (Canis familiaris) affects 5-10% of the population in affluent countries. Three of four patients are allergic to more than one pet, which can only partially be explained by cross-reactivity between serum albumins. The lipocalin protein family harbours allergens in mammalian species.

Methods: We set out to clone and characterize a novel dog allergen, and investigate its potential role in cross-sensitization between dog, cat and horse. The gene encoding Can f 6 was amplified from dog skin and bladder cDNA libraries. The corresponding allergen was produced and purified by recombinant techniques and evaluated by SDS-PAGE, size exclusion chromatography, circular dichroism spectra, ELISA and basophil activation test.

Results: IgE antibodies to Can f 6 were found in serum from 38% of dog-sensitized subjects. Sequence similarities between the lipocalin allergens Can f 6, Fel d 4 (cat) and Equ c 1 (horse) suggested a probability for cross-reactivity, which was demonstrated by competitive ELISA. The biological relevance of Can f 6 was confirmed by basophil activation test in dog-allergic patients.

Conclusion: Can f 6 is a new lipocalin dog allergen that cross-reacts with lipocalins from horse and cat. Can f 6 and homologous allergens may contribute to multisensitization and symptoms in individuals allergic to mammals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Allergens / immunology*
  • Amino Acid Sequence
  • Animals
  • Basophil Degranulation Test
  • Cats
  • Child
  • Child, Preschool
  • Cross Reactions
  • Dogs
  • Female
  • Gene Library
  • Horses
  • Humans
  • Hypersensitivity / immunology*
  • Infant
  • Lipocalins / immunology*
  • Male
  • Middle Aged
  • Molecular Sequence Data
  • Sequence Homology, Amino Acid
  • Young Adult


  • Allergens
  • Lipocalins