Development of two types of mite-allergen induced murine models of chronic asthma with different severity

Asthma is an allergic disease characterized by chronic airway inflammation, hyper-responsiveness (AHR), and reversible obstruction. The main inflammatory changes are induced by infiltration of eosinophils into the airway. Few animal models resemble the spontaneous history of asthma due to variations in the selection of the mouse strain, appropriate antigen, and exposure methods. Here, we prepared two different mouse models in which the mechanism was close to that of human asthma. We transnasally administered mite Dermatophagoides farinae (Df) allergen to BALB/c mice 10 times (Df-2) or 25 times (Df-5). After comparison with mice administered phosphate-buffered saline, the AHR and immediate asthmatic response were evaluated, in addition to the number of eosinophils in the bronchoalveolar lavage fluid (BALF). Df-specific IgE and IgG1 levels in the serum, and Th2 cytokines (interleukin [IL]-5, IL-13) in the BALF were measured by enzymelinked immunosorbent assay. Immediate asthmatic response and AHR were enhanced in mite allergen-treated mice (Df-2 and Df-5) compared to PBS-treated mice. The number of eosinophils and IL-13 levels in the BALF, and specific IgE in the serum were greater in Df-5 than in Df-2 mice. We established two different murine chronic asthma models, in which the severity depended on the number of exposures to Df. Greater intranasal exposure to a Df allergen resulted in more severe asthma in a BALB/c mouse model