Identification of a polygalacturonase (Cup s 2) as the major CCD-bearing allergen in Cupressus sempervirens pollen

Allergy. 2017 Nov;72(11):1806-1810. doi: 10.1111/all.13191. Epub 2017 May 22.


As IgE glyco-epitopes, also referred to as cross-reactive carbohydrate determinants (CCDs), can share significant structural homologies between different plants, they are prone to extensive cross-reactivity among allergen pollen extracts. Here, cypress pollen allergens, especially a polygalacturonase (PG), were further characterized using double one-dimensional electrophoresis (D1-DE). The presence of specific IgE directed against CCDs was investigated by bromelain IgE inhibition and concanavalin A binding assays using sera of cypress pollen-sensitized patients. Our results showed that IgE reactivity to CCDs in Cupressus sempervirens pollen extracts is mainly related to bromelain-type epitopes of a newly identified cypress PG. This glycoprotein has been further characterized through an immunoproteomic approach and officially indexed as Cup s 2 by the WHO/IUIS allergen nomenclature. Cup s 2 could thus be associated with the increased prevalence of IgE reactivity to cypress pollen extracts because of CCD interference.

Keywords: Cupressus sempervirens; bromelain; cross-reactive carbohydrate determinant; cypress pollen allergens; polygalacturonase.

MeSH terms

  • Allergens / immunology*
  • Antigens, Plant / immunology
  • Cross Reactions / immunology*
  • Cupressus / immunology*
  • Immunoglobulin E / immunology
  • Pollen / immunology
  • Polygalacturonase / immunology*


  • Allergens
  • Antigens, Plant
  • Immunoglobulin E
  • Polygalacturonase