title: Allergic Non-Asthmatic Adults Have Regional Pulmonary Responses to Segmental Allergen Challenge.
abstract: BACKGROUND
  Allergic non-asthmatic (ANA) adults experience upper airway symptoms of allergic disease such as rhinorrhea, congestion and sneezing without symptoms of asthma. The aim of this study was to utilize PET-CT functional imaging to determine whether allergen challenge elicits a pulmonary response in ANA subjects or whether their allergic disease is truly isolated to the upper airways.
  
  
  METHODS
  In 6 ANA subjects, bronchoalveolar lavages (BAL) were performed at baseline and 24h after instillation of an allergen and a diluent in separate lung lobes. After instillation (10h), functional imaging was performed to quantify and compare regional perfusion, ventilation, fractional gas content (Fgas), and glucose uptake rate (Ki) between the baseline, diluent and allergen lobes. BAL cell counts were also compared.
  
  
  RESULTS
  In ANA subjects, compared to the baseline and diluent lobes, perfusion and ventilation were significantly lower in the allergen lobe (median [inter-quartile range], baseline vs. diluent vs. allergen: Mean-normalized perfusion; 0.87 [0.85-0.97] vs. 0.90 [0.86-0.98] vs. 0.59 [0.55-0.67]; p<0.05. Mean-normalized ventilation 0.89 [0.88-0.98] vs. 0.95 [0.89-1.02] vs. 0.63 [0.52-0.67], p<0.05). In contrast, no significant differences were found in Fgas between baseline, diluent and allergen lobes or in Ki. Total cell counts, eosinophil and neutrophil cell counts (cells/ml BAL) were significantly greater in the allergen lobe compared to the baseline lobe (all P<0.05).
  
  
  CONCLUSIONS
  Despite having no clinical symptoms of a lower airway allergic response (cough and wheeze) allergic non-asthmatic subjects have a pulmonary response to allergen exposure which manifests as reduced ventilation and perfusion.
authors.affiliation: Divisions of Pulmonary and Critical Care and Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Vanessa J
authors.initials: VJ
authors.lastname: Kelly
authors.affiliation: Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Tilo
authors.initials: T
authors.lastname: Winkler
authors.affiliation: Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Jose G
authors.initials: JG
authors.lastname: Venegas
authors.affiliation: Divisions of Pulmonary and Critical Care and Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Mamary
authors.initials: M
authors.lastname: Kone
authors.affiliation: Divisions of Pulmonary and Critical Care and Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Hamilos
authors.affiliation: Divisions of Pulmonary and Critical Care and Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.|Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Roshi
authors.initials: R
authors.lastname: Afshar
authors.affiliation: Divisions of Pulmonary and Critical Care and Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.|Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Josalyn L
authors.initials: JL
authors.lastname: Cho
authors.affiliation: Divisions of Pulmonary and Critical Care and Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.|Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Luster
authors.affiliation: Divisions of Pulmonary and Critical Care and Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.|Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Benjamin D
authors.initials: BD
authors.lastname: Medoff
authors.affiliation: Divisions of Pulmonary and Critical Care and Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: R Scott
authors.initials: RS
authors.lastname: Harris
mesh_terms: D000328:Adult; D000485:Allergens / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D008168:Lung / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D000485:Allergens