Interaction of Ozone and Allergen Challenges on Bronchial Responsiveness and Inflammation in Sensitised Guinea Pigs

Abstract

Background: Environmental pollutants such as ozone may interact with airway responses to allergen in sensitised individuals. Methods: We examined the effects of a single exposure to ozone (1 ppm for 1 h) on bronchial responsiveness to acetylcholine (ACh) aerosol 3 and 24 h after single ovalbumin (OA) challenge in OA-sensitised anaesthetised guinea pigs. Broncho-alveolar lavage (BAL) was performed and protein content and differential cell counts were determined. Results: Ozone increased bronchial responsiveness at 3 h but not at 24 h, while OA alone had no effect. At 3 h after ozone, OA induced further, but non-significant increases in bronchial responsiveness to ACh, but at 24 h after ozone, there was enhanced responsiveness. Neutrophil counts in BAL fluid increased at 3 and 24 h after exposure to ozone alone, but there were no further increases with ozone followed by OA exposure. Protein concentration was significantly increased in the ozone and OA groups at 3 and 24 h (163.4 ± 25.6 and 128.7 ± 7.4 mg/ml, respectively) compared to 54.0 ± 18.1 mg/ml in the control group (p < 0.02 and p < 0.01, respectively). Conclusion: Our data demonstrate an interaction of OA with ozone exposure on bronchial responsiveness; one underlying mechanism could be through damage at the endothelial-epithelial barrier.

Impact of East Asian Summer Monsoon on Surface Ozone Pattern in China

“…Currently, more and more evidences show that a long-term exposure to high concentrations of ozone in the environment may be harmful to the human body, which may cause permanent damage to lungs, especially for small children, patients with asthma, and the elderly. (Folinsbee et al, 1988;Horstman et al, 1990;Jorres et al, 1996;Kehrl et al, 1999;Molfino et al, 1991;Peden et al, 1995;Roux et al, 1999;Sun et al, 1997).…”

Spatio-Temporal Characteristics of Tropospheric Ozone and Its Precursors in Guangxi, South China

“…As the third most important greenhouse gas and one of the most important components of photochemical smog, tropospheric ozone originates from the stratosphere and troposphere exchange (STE) process and photochemical reactions involving its precursors, such as nitrogen dioxides (NO x = NO + NO 2 ), volatile organic compounds (VOCs), CO and CH 4 [1]. High concentrations of ozone have adverse effects on human health and ecosystem productivity near the surface layer [2][3][4][5][6][7][8]. Therefore, understanding and measuring ozone and its precursors has become more important, and tropospheric ozone has already been included as a routine monitoring component in the new air quality standard of 2013 (http://kjs.mep.gov.cn/).…”

Combined effects of aerobiological pollutants, chemical pollutants and meteorological conditions on asthma admissions and A & E attendances in Derbyshire UK, 1993–96.

“…In vivo studies have demonstrated an enhanced IgE production to allergen upon exposure to diesel exhaust particles [5]. Exposure to nitrogen dioxide, ozone and diesel particles have all been associated with increased airway responsiveness to allergen challenge in animal or chamber studies [6–10]. Collectively therefore these data suggest that the effects of various pollutants and aeroallergens might interact, but whether this occurs at ambient concentrations and pollutant aeroallergen mixtures, and how relatively important these interactions are to asthma morbidity at the individual or population level is unknown.…”