Defensin-like proteins

Allergologically relevant proteins that have so far only been found in the Aster family. Besides the plant defensins, they play an important role as "defense proteins" in the plant immune system (synonym: pathogenesis-related (PR)12 protein). This is also expressed by their concentration in the outer cell layers of the pollen. Apparently, these proteins also play a role in the fertilization of plants.

Important allergens of this protein family are: amb a 4 of the dove's weed (Ambrosia artemsiifolia), species v 1 of the mugwort (Artemesia vulgaris) or Hel a 1 of the sunflower (Helianthus annuus). Species v 1 of mugwort pollen has the greatest allergological significance. The conformative IgE epitopes are mainly located on the defensin domain. The D-terminal domain and glycans have only minor allergological relevance.

1. Gadermaier G et al (2009) Targeting the cysteine-stabilized fold of art v 1for
   immunotherapy of Artemisia pollen allergy. Mol Immunol 47:1292-1298.

2. Léonard R et al (2010) A new allergen from ragweed (Ambrosia artemisiifolia) with homology to art v 1 from mugwort. J Biol Chem 285: 27192-27200.

3. Stemeseder T et al (2010) Marker allergens of weed pollen - basic considerations and diagnostic benefits in the clinical routine: Part 16 of the Series Molecular Allergology. Allergo J Int 23:274-280.