title: Variation of the group 5 grass pollen allergen content of airborne pollen in relation to geographic location and time in season.
abstract: BACKGROUND
  Allergies to grass pollen are the number one cause of outdoor hay fever. The human immune system reacts with symptoms to allergen from pollen.
  
  
  OBJECTIVE
  We investigated the natural variability in release of the major group 5 allergen from grass pollen across Europe.
  
  
  METHODS
  Airborne pollen and allergens were simultaneously collected daily with a volumetric spore trap and a high-volume cascade impactor at 10 sites across Europe for 3 consecutive years. Group 5 allergen levels were determined with a Phl p 5-specific ELISA in 2 fractions of ambient air: particulate matter of greater than 10 μm in diameter and particulate matter greater than 2.5 μm and less than 10 μm in diameter. Mediator release by ambient air was determined in FcεRI-humanized basophils. The origin of pollen was modeled and condensed to pollen potency maps.
  
  
  RESULTS
  On average, grass pollen released 2.3 pg of Phl p 5 per pollen. Allergen release per pollen (potency) varied substantially, ranging from less than 1 to 9 pg of Phl p 5 per pollen (5% to 95% percentile). The main variation was locally day to day. Average potency maps across Europe varied between years. Mediator release from basophilic granulocytes correlated better with allergen levels per cubic meter (r(2) = 0.80, P < .001) than with pollen grains per cubic meter (r(2) = 0.61, P < .001). In addition, pollen released different amounts of allergen in the non-pollen-bearing fraction of ambient air, depending on humidity.
  
  
  CONCLUSIONS
  Across Europe, the same amount of pollen released substantially different amounts of group 5 grass pollen allergen. This variation in allergen release is in addition to variations in pollen counts. Molecular aerobiology (ie, determining allergen in ambient air) might be a valuable addition to pollen counting.
authors.affiliation: ZAUM-Center of Allergy & Environment, Helmholtz Center Munich/Technische Universität München, Member of the German Center for Lung Research (DZL), Munich, Germany; Kühne Foundation, Christine Kühne-Center for Allergy Research and Education (CK-CARE), Munich, Germany. Electronic address: buters@tum.de.
authors.forename: Jeroen
authors.initials: J
authors.lastname: Buters
authors.affiliation: Finnish Meteorological Institute, Erik Palmenin Aukio 1, Helsinki, Finland.
authors.forename: Marje
authors.initials: M
authors.lastname: Prank
authors.affiliation: Finnish Meteorological Institute, Erik Palmenin Aukio 1, Helsinki, Finland.
authors.forename: Mikhail
authors.initials: M
authors.lastname: Sofiev
authors.affiliation: ZAUM-Center of Allergy & Environment, Helmholtz Center Munich/Technische Universität München, Member of the German Center for Lung Research (DZL), Munich, Germany; Kühne Foundation, Christine Kühne-Center for Allergy Research and Education (CK-CARE), Munich, Germany.
authors.forename: Gudrun
authors.initials: G
authors.lastname: Pusch
authors.affiliation: Laboratory of Allergology, Department of Clinical and Experimental Medicine, University of Parma, U.O. Medical Immunology, University Hospital of Parma, Parma, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Albertini
authors.affiliation: EPAR Department, INSERM, UMR_S1136, Institut Pierre Louis d'Epidémiologie et de Santé Publique, France; EPAR Department, Sorbonne Universités, UPMC Univ Paris 06, UMR_S 1136, Institut Pierre Louis d'Epidémiologie et de Santé Publique, Paris, France.
authors.forename: Isabella
authors.initials: I
authors.lastname: Annesi-Maesano
authors.affiliation: ICAAM-Institute of Mediterranean Crop and Environmental Sciences, University of Évora, Évora, Portugal; Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal.
authors.forename: Celia
authors.initials: C
authors.lastname: Antunes
authors.affiliation: ZAUM-Center of Allergy & Environment, Helmholtz Center Munich/Technische Universität München, Member of the German Center for Lung Research (DZL), Munich, Germany; Kühne Foundation, Christine Kühne-Center for Allergy Research and Education (CK-CARE), Munich, Germany.
authors.forename: Heidrun
authors.initials: H
authors.lastname: Behrendt
authors.affiliation: Medical University of Vienna, Department of Oto-Rhino-Laryngology, Research Unit Aerobiology and Pollen Information, Vienna, Austria.
authors.forename: Uwe
authors.initials: U
authors.lastname: Berger
authors.affiliation: ICAAM-Institute of Mediterranean Crop and Environmental Sciences, University of Évora, Évora, Portugal.
authors.forename: Rui
authors.initials: R
authors.lastname: Brandao
authors.affiliation: Aerobiology Laboratory, Biology Department, Science and Arts Faculty, Uludag University, Gorukle-Bursa, Turkey.
authors.forename: Sevcan
authors.initials: S
authors.lastname: Celenk
authors.affiliation: Department of Botany, Ecology and Plant Physiology, University of Córdoba, International Campus of Excellence on Agrifood (ceiA3), Córdoba, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Galan
authors.affiliation: Laboratory of Aeropalynology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland.
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Grewling
authors.affiliation: Laboratory of Aeropalynology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland.
authors.forename: Bogdan
authors.initials: B
authors.lastname: Jackowiak
authors.affiliation: National Pollen and Aerobiology Research Unit, University of Worcester, Worcester, United Kingdom.
authors.forename: Roy
authors.initials: R
authors.lastname: Kennedy
authors.affiliation: University of Turku, CERUT, Aerobiology Unit, Turku, Finland.
authors.forename: Auli
authors.initials: A
authors.lastname: Rantio-Lehtimäki
authors.affiliation: Allergopharma GmbH & Co KG, Reinbek, Germany.
authors.forename: Gerald
authors.initials: G
authors.lastname: Reese
authors.affiliation: Department of Environmental Research, Siauliai University, Siauliai, Lithuania.
authors.forename: Ingrida
authors.initials: I
authors.lastname: Sauliene
authors.affiliation: Medical University of Vienna, Department of Oto-Rhino-Laryngology, Research Unit Aerobiology and Pollen Information, Vienna, Austria.
authors.forename: Matt
authors.initials: M
authors.lastname: Smith
authors.affiliation: RNSA (Réseau National de Surveillance Aérobiologique), Brussieu, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Thibaudon
authors.affiliation: Allergopharma GmbH & Co KG, Reinbek, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Weber
authors.affiliation: Interdepartmental Centre of Bioclimatology, University of Florence, Florence, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Cecchi
mesh_terms: D000388:Air / Q000032:analysis*; D001491:Basophils / Q000502:physiology*; D015550:Cell Degranulation; D005060:Europe; D006801:Humans; D006813:Humidity; D052638:Particulate Matter / Q000032:analysis*; D010940:Plant Proteins / Q000032:analysis*; D006109:Poaceae / Q000276:immunology; D011058:Pollen / Q000737:chemistry*; D017455:Receptors, IgE / Q000235:genetics / Q000378:metabolism*; D006255:Rhinitis, Allergic, Seasonal / Q000453:epidemiology / Q000276:immunology*; D012621:Seasons
chemical_list: C543372:FcepsilonRI gamma-chain, human; D052638:Particulate Matter; C076049:Phl p V protein, Phleum pratense; D010940:Plant Proteins; D017455:Receptors, IgE
keywords: Allergen; Europe; HIALINE; PM10; PM2.5; Phl p 5; SILAM; allergy; basophil; exposure; grass; modeling