title: Identification of the cysteine protease Amb a 11 as a novel major allergen from short ragweed.
abstract: BACKGROUND
  Allergy to pollen from short ragweed (Ambrosia artemisiifolia) is a serious and expanding health problem in the United States and in Europe.
  
  
  OBJECTIVE
  We sought to investigate the presence of undescribed allergens in ragweed pollen.
  
  
  METHODS
  Ragweed pollen proteins were submitted to high-resolution gel electrophoresis and tested for IgE reactivity by using sera from 92 American or European donors with ragweed allergy. Pollen transcriptome sequencing, mass spectrometry (MS), and recombinant DNA technologies were applied to characterize new IgE-binding proteins.
  
  
  RESULTS
  High-resolution IgE immunoblotting experiments revealed that 50 (54%) of 92 patients with ragweed allergy were sensitized to a 37-kDa allergen distinct from Amb a 1. The full-length cDNA sequence for this molecule was obtained by means of PCR cloning after MS sequencing of the protein combined with ragweed pollen RNA sequencing. The purified allergen, termed Amb a 11, was fully characterized by MS and confirmed to react with IgEs from 66% of patients. This molecule is a 262-amino-acid thiol protease of the papain family expressed as a combination of isoforms and glycoforms after proteolytic removal of N- and C-terminal propeptides from a proform. Three-dimensional modeling revealed a high structural homology with known cysteine proteases, including the mite Der p 1 allergen. The protease activity of Amb a 11, as well as its capacity to activate basophils from patients with ragweed allergy, were confirmed. The production of a nonglycosylated recombinant form of Amb a 11 in Escherichia coli established that glycosylation is not required for IgE binding.
  
  
  CONCLUSIONS
  We identified the cysteine protease Amb a 11 as a new major allergen from ragweed pollen. Given the similar physicochemical properties shared by the 2 major allergens, we hypothesize that part of the allergenic activity previously ascribed to Amb a 1 is rather borne by Amb a 11.
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Julien
authors: J
authors: Bouley
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Rachel
authors: R
authors: Groeme
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Maxime
authors: M
authors: Le Mignon
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Karine
authors: K
authors: Jain
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Henri
authors: H
authors: Chabre
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Véronique
authors: V
authors: Bordas-Le Floch
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Marie-Noëlle
authors: MN
authors: Couret
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Laetitia
authors: L
authors: Bussières
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Aurélie
authors: A
authors: Lautrette
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Marie
authors: M
authors: Naveau
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Véronique
authors: V
authors: Baron-Bodo
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Vincent
authors: V
authors: Lombardi
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Laurent
authors: L
authors: Mascarell
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Thierry
authors: T
authors: Batard
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France.
authors: Emmanuel
authors: E
authors: Nony
authors: Research & Pharmaceutical Development, Stallergenes, Antony, France. Electronic address: pmoingeon@stallergenes.com.
authors: Philippe
authors: P
authors: Moingeon
mesh_terms: D031164:Ambrosia / Q000201:enzymology / Q000235:genetics / Q000276:immunology; D001483:Base Sequence; D003001:Cloning, Molecular; D057056:Cysteine Proteases / Q000235:genetics / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000276:immunology; D006255:Rhinitis, Allergic, Seasonal / Q000276:immunology*
chemical_list: D010940:Plant Proteins; D057056:Cysteine Proteases
keywords: Allergen; Amb a 11; Ambrosia artemisiifolia; cysteine protease; mass spectrometry; short ragweed