Effect of Diesel Exhaust Particles on House Dust Mite–Induced Airway Eosinophilic Inflammation and Remodeling in Mice

Abstract

Abstract. Recent research has focused on the effects of ambient particulate pollution and much evidence has indicated that particulate pollution is associated with the onset of asthma and allergy; however, the effect of diesel exhaust particles (DEP) on the development of allergen-induced airway remodeling has not been fully investigated in vivo. In the present study, we examined the effects of DEP on Dermatophagoides farinae allergens (Der f)-induced asthma-like phenotypes in mice. Mice were administered i.t. 8 times with Der f. DEP were injected i.t. with Der f 4 times throughout the experiment or twice at the sensitization period. In both cases, DEP aggravated Der f-induced increases in airway responsiveness to acetylcholine, the number of eosinophils and neutrophils in the bronchoalveolar lavage fluid (BALF), serum Der f-specific IgG1 levels, Th2 cytokines and transforming growth factor-β 1 levels in BALF, and amount of hydroxyproline in the right lungs. Furthermore, goblet cell hyperplasia and subepithelial fibrosis were also markedly aggravated. These findings indicate that DEP can potentiate airway remodeling induced by repeated allergen challenge as well as Th2-drived airway hyperresponsiveness, eosinophilic inflammation, and IgG1 production and that DEP can exhibit adjuvant activity for airway remodeling, probably due to the enhancement of allergen sensitization and/or of Th2 polarizing pathways.

Mode of dendritic cell activation: The decisive hand in Th2/Th17 cell differentiation. Implications in asthma severity?

“…DEP exposure decreases lung function and increases neutrophil biomarkers (McCreanor et al 2007). Exposure of young and adult mice to a combination of DEP and HDM has been shown to provoke an exaggerated Th2 and mixed Th2/Th17 cell mediated inflammatory response in the airways (Takahashi et al 2009;Acciani et al 2013). Strikingly, collagen content is increased in the lungs of DEP/HDM exposed adult mice, indicative of lung remodeling.…”

Exacerbation of Allergic Diseases by Chemicals: Role of TSLP

“…In an experimental asthma model using Dermatophagoides farinae allergens (Der f), the injection of DEPs with Der f enhanced the production of Th2 cytokines, eosinophil infiltration, and airway remodeling (24). Although it has not yet been clarified whether DEP-induced TSLP influences the exacerbation of these allergic manifestations in vivo, Bleck et al reported that DEPs induced TSLP production in human bronchial epithelial cells (HBECs) (25,26).…”

Near-Road Exposure to Air Pollution and Allergic Rhinitis: A Cross-Sectional Study among Vendors in Dakar, Senegal

“…The fine particles, mostly derived from road traffic, are ultrafine size (<100 nm) and can be deposited in the nasal and peripheric airways. These fine particles induce oxidative stress and hyper-reactivity of the respiratory tract by increasing inflammation of the respiratory tract and allergic responses such as allergic rhinitis [15]. Vendors who had a long daily working time, had a higher prevalence of allergic rhinitis.…”

“…These pollutants can induce oxidative stress and hyperreactivity of the airways. As a result, they increase allergic responses and inflammation of the respiratory tract [13] [14] [15]. Air pollution from cars is therefore a major risk factor for increasing the prevalence of allergic rhinitis.…”