Abstract:Objective To investigate the effects of different doses of ovalbumin (OVA) on the serum levels ofIgE, IL-4, and IFN-γ, on the number of eosinophils (EOS) in bronchoalveolar lavage fluid (BALF), and on lunghistopathology in the BALB/ c mice with bronchial asthma, to determine the optimal OVA dose. Methods BALB/ c micewere randomly divided into a normal group, model 1 group (OVA 20 μg), model 2 group (OVA 50 μg), model 3 group(OVA 100 μg), and dexamethasone acetate group (OVA 100 μg). In addition to the normal group, the other groups ofmice were sensitized by intraperitoneal injection of the corresponding doses of OVA, and stimulated by 1% OVA atomizationto establish bronchial asthma models. The serum levels of IgE, IL-4, and IFN-γ were determined by ELISA. The number ofEOS in BALF was calculated by Wright staining, and the pathological changes of lung tissue were observed by HE staining.Results Compared with the normal group, the serum levels of IgE, IL-4, and IFN-γ and EOS in BALF were significantlyincreased in all groups ( P <0. 05). Inflammatory cell infiltration, bronchial epithelial cell degeneration, bronchial smoothmuscle cell hyperplasia, and other pathological changes were observed in the lung tissues. Especially, in the OVA 50 μggroup, the changes in the IgE, IL-4, and IFN-γ levels and lung histopathological changes were more pronounced. Conclusions All the three doses of OVA can induce asthma in BALB/ c mice successfully, and the asthma model inducedby 50 μg of OVA had more pronounced alterations. It is recommended that 50 μg of OVA be used as the appropriate dosage for establishing an asthma model in BALB/ c mice.