Airway inflammatory and immunological events in a rat model exposed to toluene diisocyanate

• Published in: Food and chemical toxicology Vol. 43; no. 8; pp. 1281 - 1288
• Main Authors: Kouadio, Kouame, Zheng, Kui-Cheng, Tuekpe, Mallet K.-N., Todoriki, Hidemi, Ariizumi, Makoto
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.08.2005; New York, NY Elsevier Science
• Subjects: Administration, Inhalation; Allergens - toxicity; Animals; asthma; Biological and medical sciences; Bronchi - drug effects; Bronchi - immunology; Bronchi - pathology; Bronchial Hyperreactivity - chemically induced; Bronchial Hyperreactivity - immunology; Bronchial Hyperreactivity - pathology; Bronchoalveolar Lavage Fluid - cytology; Bronchoalveolar Lavage Fluid - immunology; Cytokines; Cytokines - metabolism; Disease Models, Animal; Eosinophils; Eosinophils - drug effects; Eosinophils - pathology; Female; food packaging; inflammation; Inhalation Exposure; Medical sciences; Occupational asthma; occupational health and safety; packaging materials; polyurethanes; Rats; Rats, Wistar; respiratory system; TDI; toluene; Toluene 2,4-Diisocyanate - toxicity; Toxicology; TDI; Cytokines; Occupational asthma; Eosinophils; Lung disease; Rat; Respiratory disease; Rodentia; Cytokine; Inflammation; Eosinophil; Asthma; Vertebrata; Mammalia; Animal; Bronchus disease; Models; Obstructive pulmonary disease
• ISSN: 0278-6915; 1873-6351
• DOI: 10.1016/j.fct.2005.03.005

To investigate the inflammatory and immunological events in the airway induced by a short period of repeated exposure to toluene diisocyanate (TDI), an animal model was established, which resembled the industrial field exposure. After whole body exposure of Wistar rats to 0.38 and 1.20 ppm TDI vapor 4 h a day for five consecutive days in a glass chamber, bronchoalveolar lavage (BAL) was performed. BAL fluid cellular and cytokine contents were then determined. Histopathological examinations were also carried out on the lungs. The TDI vapor exposure resulted in airway symptoms similar to those in occupational asthma. BAL fluid cellular analysis and lung histophathological examination revealed that inflammatory response was characterized by marked eosinophil infiltration of the airways. The cytokine assay revealed significant production of IL-4 in the airways of the TDI exposed rats as compared to the control rats. These findings indicated that a short period of repeated exposure to TDI vapor may cause respiratory hypersensitivity in which airway inflammatory and immunological events represented by eosinophil infiltration and Th2 cytokines may play an important role. Also, this animal model may be suitable for exploring the mechanism underlying TDI-induced occupational asthma.