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The house dust mites ( Dermatophagoides farinae, Der f) are the major source of aeroallergens implicated in the expression of atopic disorders, including asthma, allergic rhinitis and atopic dermatitis. In particular, strong circumstantial evidence suggests that house dust mite antigens are important precipitating factors of asthma. Many house dust mite allergens are proteases that can elicit airway inflammation by stimulating the release of cytokines from bronchial epithelial cells. To investigate whether Derf allergen proteases induced cytokine production from the epithelial cell line BEAS-2B,BEAS-2B cells were cultured with 4 different concentrations of Derf (0.02, 0.2, 2, 20 μg/ml) for 24-96 h, after which supeatants were assayed for interleukin (IL)-6 and IL-8 with ELISA. Reverse transcription-PCR was also performed. The cell sheets were intact throughout the observation in control group without any exposure to Derf antigen. In the experimental groups cells treated with Der f allergen showed changes in the anchorage status of the monolayer. There was a significant increase in the level of cytokine production compared with the untreated sample. The release of IL-6 and IL-8 increased in a concentration-dependent manner ( P ＜ 0.05, respectively) with the addition of increasing dosage of Der f to the cell sheets. Levels of IL-6 and IL-8 began to rise at 24 h and 48 h after allergen exposure, and they increased significantly in the supeatants at 72 h and 96 h. At the same time the concentration dependence of induction of IL-6 and IL-8 expression as well as an increase in the expression of IL-6 and IL-8 mRNA manifested evidently. HDM-induced airway inflammation may include Der f-mediated release of inflammatory mediators, and the proteolytic activity of an allergen may stimulate the release of proinflammatory cytokines from human bronchial epithelium. It is suggested that IL-6 and IL-8 production by bronchial epithelial cells may play a role in the pathogenesis of allergic asthma.