Airway inflammatory responses to diesel exhaust in allergic rhinitics.
Inhal Toxicol
; 25(3): 160-7, 2013 Feb.
Article
em En
| MEDLINE
| ID: mdl-23421487
ABSTRACT
CONTEXT Proximity to traffic, particularly to diesel-powered vehicles, has been associated with inducing and enhancing allergies. To investigate the basis for this association, we performed controlled exposures of allergic rhinitics to diesel exhaust (DE) at a dose known to be pro-inflammatory in healthy individuals. OBJECTIVE:
We hypothesized that diesel-exhaust exposure would augment lower airway inflammation in allergic rhinitics. MATERIALS ANDMETHODS:
Fourteen allergic rhinitics were exposed in a double-blinded, randomized trial to DE (100 µg/m³ PM10) and filtered air for 2 h on separate occasions. Bronchoscopy with endobronchial mucosal biopsies and airway lavage was performed 18 h post-exposure, and inflammatory markers were assessed.RESULTS:
No evidence of neutrophilic airway inflammation was observed post-diesel, however, a small increase in myeloperoxidase was found in bronchoalveolar lavage (p = 0.032). We found no increases in allergic inflammatory cells. Reduced mast cell immunoreactivity for tryptase was observed in the epithelium (p = 0.013) parallel to a small decrease in bronchial wash stem cell factor (p = 0.033). DISCUSSION ANDCONCLUSION:
DE, at a dose previously shown to cause neutrophilic inflammation in healthy individuals, induced no neutrophilic inflammation in the lower airways of allergic rhinitics, consistent with previous reports in asthmatics. Although there was no increase in allergic inflammatory cell numbers, the reduction in tryptase in the epithelium may indicate mast cell degranulation. However, this occurred in the absence of allergic symptoms. These data do not provide a simplistic explanation of the sensitivity in rhinitics to traffic-related air pollution. The role of mast cells requires further investigation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Emissões de Veículos
/
Rinite Alérgica Perene
/
Mucosa Respiratória
/
Poluentes Atmosféricos
Tipo de estudo:
Clinical_trials
Limite:
Adult
/
Female
/
Humans
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Male
Idioma:
En
Revista:
Inhal Toxicol
Assunto da revista:
TOXICOLOGIA
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Suécia