BACKGROUND: Proof is lacking that pollen count is representative for allergen exposure, also because allergens were found in nonpollen-bearing fractions of ambient air. OBJECTIVE: We monitored simultaneously birch pollen and the major birch pollen allergen Bet v 1 in different size fractions of ambient air from 2004 till 2007 in Munich, Germany. METHODS: Air was sampled with a ChemVol high-volume cascade impactor equipped with stages for particulate matter (PM)>10 microm, 10 microm>PM>2.5 microm, and 2.5 microm>PM>0.12 microm. Allergen was determined with a Bet v 1-specific ELISA. Pollen count was assessed with a Burkard pollen trap. We also measured the development of allergen in pollen during ripening. RESULTS: About 93 +/- 3% of Bet v 1 was found in the PM > 10 microm fraction, the fraction containing birch pollen. We did not measure any Bet v 1 in 2.5 microm > PM > 0.12 microm. Either in Munich no allergen was in this fraction or the allergen was absorbed to diesel soot particles that also deposit in this fraction. Pollen released 115% more Bet v 1 in 2007 than in 2004. Also within 1 year, the release of allergen from the same amount of pollen varied more than 10-fold between different days. This difference was explained by a rapidly increasing expression of Bet v 1 in pollen in the week just before pollination. Depending on the day the pollen is released during ripening, its potency varies. CONCLUSION: In general, pollen count and allergen in ambient air follow the same temporal trends. However, because a 10-fold difference can exist in allergen potency of birch pollen, symptoms might be difficult to correlate with pollen counts, but perhaps better with allergen exposure.
BACKGROUND: Proof is lacking that pollen count is representative for allergen exposure, also because allergens were found in nonpollen-bearing fractions of ambient air. OBJECTIVE: We monitored simultaneously birch pollen and the major birch pollen allergen Bet v 1 in different size fractions of ambient air from 2004 till 2007 in Munich, Germany. METHODS: Air was sampled with a ChemVol high-volume cascade impactor equipped with stages for particulate matter (PM)>10 microm, 10 microm>PM>2.5 microm, and 2.5 microm>PM>0.12 microm. Allergen was determined with a Bet v 1-specific ELISA. Pollen count was assessed with a Burkard pollen trap. We also measured the development of allergen in pollen during ripening. RESULTS: About 93 +/- 3% of Bet v 1 was found in the PM > 10 microm fraction, the fraction containing birch pollen. We did not measure any Bet v 1 in 2.5 microm > PM > 0.12 microm. Either in Munich no allergen was in this fraction or the allergen was absorbed to diesel soot particles that also deposit in this fraction. Pollen released 115% more Bet v 1 in 2007 than in 2004. Also within 1 year, the release of allergen from the same amount of pollen varied more than 10-fold between different days. This difference was explained by a rapidly increasing expression of Bet v 1 in pollen in the week just before pollination. Depending on the day the pollen is released during ripening, its potency varies. CONCLUSION: In general, pollen count and allergen in ambient air follow the same temporal trends. However, because a 10-fold difference can exist in allergen potency of birch pollen, symptoms might be difficult to correlate with pollen counts, but perhaps better with allergen exposure.
Authors: Kathryn M Emmerson; Jeremy D Silver; Marcus Thatcher; Alan Wain; Penelope J Jones; Andrew Dowdy; Edward J Newbigin; Beau W Picking; Jason Choi; Elizabeth Ebert; Tony Bannister Journal: PLoS One Date: 2021-04-14 Impact factor: 3.240
Authors: Danielle E Medek; Paul J Beggs; Bircan Erbas; Alison K Jaggard; Bradley C Campbell; Don Vicendese; Fay H Johnston; Ian Godwin; Alfredo R Huete; Brett J Green; Pamela K Burton; David M J S Bowman; Rewi M Newnham; Constance H Katelaris; Simon G Haberle; Ed Newbigin; Janet M Davies Journal: Aerobiologia (Bologna) Date: 2015-07-29 Impact factor: 2.410
Authors: Gennaro D'Amato; Stephen T Holgate; Ruby Pawankar; Dennis K Ledford; Lorenzo Cecchi; Mona Al-Ahmad; Fatma Al-Enezi; Saleh Al-Muhsen; Ignacio Ansotegui; Carlos E Baena-Cagnani; David J Baker; Hasan Bayram; Karl Christian Bergmann; Louis-Philippe Boulet; Jeroen T M Buters; Maria D'Amato; Sofia Dorsano; Jeroen Douwes; Sarah Elise Finlay; Donata Garrasi; Maximiliano Gómez; Tari Haahtela; Rabih Halwani; Youssouf Hassani; Basam Mahboub; Guy Marks; Paola Michelozzi; Marcello Montagni; Carlos Nunes; Jay Jae-Won Oh; Todor A Popov; Jay Portnoy; Erminia Ridolo; Nelson Rosário; Menachem Rottem; Mario Sánchez-Borges; Elopy Sibanda; Juan José Sienra-Monge; Carolina Vitale; Isabella Annesi-Maesano Journal: World Allergy Organ J Date: 2015-07-14 Impact factor: 4.084
Authors: Giorgio Walter Canonica; Linda Cox; Ruby Pawankar; Carlos E Baena-Cagnani; Michael Blaiss; Sergio Bonini; Jean Bousquet; Moises Calderón; Enrico Compalati; Stephen R Durham; Roy Gerth van Wijk; Désirée Larenas-Linnemann; Harold Nelson; Giovanni Passalacqua; Oliver Pfaar; Nelson Rosário; Dermot Ryan; Lanny Rosenwasser; Peter Schmid-Grendelmeier; Gianenrico Senna; Erkka Valovirta; Hugo Van Bever; Pakit Vichyanond; Ulrich Wahn; Osman Yusuf Journal: World Allergy Organ J Date: 2014-03-28 Impact factor: 4.084
Authors: Christian Seutter von Loetzen; Thessa Jacob; Olivia Hartl-Spiegelhauer; Lothar Vogel; Dirk Schiller; Cornelia Spörlein-Güttler; Rainer Schobert; Stefan Vieths; Maximilian Johannes Hartl; Paul Rösch Journal: PLoS One Date: 2015-06-04 Impact factor: 3.240
Authors: Richard Toro A; Alicia Córdova J; Mauricio Canales; Raul G E Morales S; Pedro Mardones P; Manuel A Leiva G Journal: PLoS One Date: 2015-05-06 Impact factor: 3.240