Structural and functional localization of airway effects from episodic exposure of infant monkeys to allergen and/or ozone

Journal Article · Tue Aug 01 04:00:00 EDT 2006 · Toxicology and Applied Pharmacology

DOI:https://doi.org/10.1016/j.taap.2005.12.012· OSTI ID:20850377

Joad, Jesse P ^[1]; Kott, Kayleen S ^[1]; Bric, John M ^[1]; Peake, Janice L ^[2]; Plopper, Charles G ^[2]; Schelegle, Edward S ^[2]; Gershwin, Laurel J ^[3]; Pinkerton, Kent E ^[2]

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1. Department of Pediatrics, School of Medicine, University of California, Davis, 2516 Stockton Boulevard, Sacramento, CA 95817 (United States)
2. Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California, Davis, CA 95616 (United States)
3. Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, CA 95616 (United States)

Both allergen and ozone exposure increase asthma symptoms and airway responsiveness in children. Little is known about how these inhalants may differentially modify airway responsiveness in large proximal as compared to small distal airways. We evaluated whether bronchi and respiratory bronchioles from infant monkeys exposed episodically to allergen and/or ozone differentially develop intrinsic hyperresponsiveness to methacholine and whether eosinophils and/or pulmonary neuroendocrine cells play a role. Infant monkeys were exposed episodically for 5 months to: (1) filtered air, (2) aerosolized house dust mite allergen, (3) ozone 0.5 ppm, or (4) house dust mite allergen + ozone. Studying the function/structure relationship of the same lung slices, we evaluated methacholine airway responsiveness and histology of bronchi and respiratory bronchioles. In bronchi, intrinsic responsiveness was increased by allergen exposure, an effect reduced by bombesin antagonist. In respiratory bronchioles, intrinsic airway responsiveness was increased by allergen + ozone exposure. Eosinophils were increased by allergen and allergen + ozone exposure in bronchi and by allergen exposure in respiratory bronchioles. In both airways, exposure to allergen + ozone resulted in fewer tissue eosinophils than did allergen exposure alone. In bronchi, but not in respiratory bronchioles, the number of eosinophils and neuroendocrine cells correlated with airway responsiveness. We conclude that episodically exposing infant monkeys to house dust mite allergen with or without ozone increased intrinsic airway responsiveness to methacholine in bronchi differently than in respiratory bronchioles. In bronchi, eosinophils and neuroendocrine cells may play a role in the development of airway hyperresponsiveness.

• OSTI ID: 20850377
• Journal Information: Toxicology and Applied Pharmacology, Journal Name: Toxicology and Applied Pharmacology Journal Issue: 3 Vol. 214; ISSN TXAPA9; ISSN 0041-008X
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
ASTHMA
BRONCHI
DUSTS
EOSINOPHILS
HISTOLOGY
INFANTS
LUNGS
MITES
MONKEYS
OZONE
SYMPTOMS