Effect of IL-5 soluble receptor and IL-4 mutant on airway hyperresponsiveness and IgE and IFN-γ in asthmatic mice

Objective By observing the effect of IL-5 soluble receptor α (sIL-5Rα) combined with IL-4 mutant (IL-4MT) on airway hyperresponsiveness (AHR) and IgE and IFN-γ in asthmatic mice,explore its potential value in clinical application.Methods Fifty female BALB/c mice were randomly divided into five groups,which were normal control group,asthma group,IL-4MT treatment group,sIL-5Rα treatment group and IL-4MT+sIL-5Rα treatment group (the combined treatment group).The mice were sensitized by intraperitoneal injection of ovalbumin (OVA) and aluminium hydroxide suspension,and atomizd with ovalbumin,to establish a murine model of asthma,the normal control group were treated with saline instead.IL-4MT treatment group,sIL-5Rα treatment group and combined treatment group were injected with IL-4MT (100 μg),sIL-5Rα(100 μg),IL-4MT (100 μg) and sIL-5Rα (100 μg) 30 minutes before atomization,the normal control group and asthma group were injected with saline.After the last challenge,mice were stimulated with different concentrations of acetylcholine chloride,determine the pulmonary resistance,observe and compare the changes of IgE,IFN-γ in serum and bronchoalveolar lavage fluid (BALF) by ELISA,lung tissue were stained with HE,to observe the pathological changes.Results Compared with the normal control group,the pulmonary resistance of asthma group significantly increased (P ＜0.01).Compared with the asthmatic group,the pulmonary resistance of IL-4MT group and combined treatment group decreased significantly (P ＜ 0.05),and the combined treatment group decreased more obviously.Compared with the sIL-5Rα treatment group,pulmonary resistance of the combined treatment group decreased significantly (P ＜0.05).Compared with the normal control group,the content of IgE in serum and BALF of asthmatic group was significantly increased,the content of IFN-γ decreased significantly (P ＜0.01).Compared with the asthma group,the content of IgE in serum and BALF of the combined treatment group decreased significantly,the content of IFN-γ was significantly increased (P ＜0.01).Compared with the single treatment group,the content of IgE in serum and BALF of the combined treatment group decreased significantly,and the content of IFN-γ was significantly increased (P ＜0.05).Compared with the asthma group,the inflammatory cell infiltration and invasion in lung tissue and airway epithelial inflammatory injury of the single treatment group and the combined treatment group was milder significantly,and the combined treatment group was more obviously.Conclusions Combined application of sIL-5Rα and IL-4MT can significantly reduce the AHR of asthmatic mice,decrease the content of IgE in serum and BALF,increase the content of IFN-γ,reduce airway inflammation. Key words: IL-5 soluble receptor;  IL-4 mutant ;  Asthma;  Airway hyperresponsiveness ;  IgE;  IFN-γ