title: Motorcycle exhaust particles augment antigen-induced airway inflammation in BALB/c mice.
abstract: Evidence indicates that environment pollutants from fossil fuel combustion compromise the immune system by enhancing allergic reactions and damaging the respiratory tract. This study was performed to investigate the effects of motorcycle exhaust particles (MEP), a major air pollutant especially in the urban areas of Taiwan, on allergen-induced airway inflammatory reactions in lab animals. BALB/c mice were intratracheally instilled with ovalbumin (OVA), MEP, or phosphate-buffered saline, 3 times every 2 wk. Airway hyperresponsiveness was measured in unrestrained mice by barometric plethsmography. Bronchoalveolar lavage fluid (BALF) and serum from treated animals were collected for cytokine and antibody determination by enzyme-linked immunosorbent assay (ELISA). Lung tissue stained with hematoxylin/eosin was examined. Data showed that MEP augmented OVA-induced airway inflammation; characterized by infiltration of eosinophils and neutrophils in BALF and lung tissue inflammation. The combination of OVA and MEP markedly increased interleukin-4 (IL-4), interleukin-5 (IL-5), and tumor necrosis factor-alpha (TNF-alpha) protein levels in BALF. In addition, MEP also augmented OVA-induced rise in OVA-specific immunoglobulin (Ig) G1 and IgE and airway hyperresponsiveness. Pretreated lavage cells with mitogen-activated protein kinase (MAPK) inhibitors showed that TNF-alpha release was significantly inhibited. This study found that MEP augmented antigen-induced allergic airway inflammation and airway hyperresponsiveness through a Th2-dominant pathway.
authors.affiliation: Department of Microbiology, School of Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Chen-Chen
authors.initials: CC
authors.lastname: Lee
authors.forename: Yu-Wen
authors.initials: YW
authors.lastname: Cheng
authors.forename: Jiunn-Wang
authors.initials: JW
authors.lastname: Liao
authors.forename: Bor-Luen
authors.initials: BL
authors.lastname: Chiang
authors.forename: Yih-Loong
authors.initials: YL
authors.lastname: Lai
authors.forename: Jaw-Jou
authors.initials: JJ
authors.lastname: Kang
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D000941:Antigens / Q000009:adverse effects / Q000276:immunology*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D006967:Hypersensitivity / Q000276:immunology / Q000473:pathology; D007073:Immunoglobulin E; D007074:Immunoglobulin G; D007249:Inflammation / Q000139:chemically induced*; D051379:Mice; D008807:Mice, Inbred BALB C; D009049:Motorcycles; D010047:Ovalbumin / Q000009:adverse effects / Q000276:immunology; D012137:Respiratory System / Q000187:drug effects* / Q000473:pathology*; D001335:Vehicle Emissions / Q000633:toxicity*
chemical_list: D000393:Air Pollutants; D000941:Antigens; D016207:Cytokines; D007074:Immunoglobulin G; D001335:Vehicle Emissions; D007073:Immunoglobulin E; D010047:Ovalbumin