The Influence Of Aerosol Inhaled Inactivated-mycobacterium On The Expression Of IL-33 In The Murine Model Of Asthma

Objectives To research the expression and effects of the IL-33 in the murine model with asthma,then evaluated the effects of inhaled inactivated-mycobacterium phlei on the expression of interleukin-33 in mice with asthma.Methods Dividing 24 male BALB/c mice into three groups:normal control group,asthma group and the asthma plus treatment group,both asthma model group and treatment group were sensitized and stimulated with ovalbumin(OVA),the treatment group were treated with phleiF.U.36 once daily after ovalbumin challenge.The same process of the normal group and the asthma group were treated with the same dose of PBS once daily for 5 days.After model established,measuring the deviation of specific airway resistance(sRaw),then killing the mice and extracting lung tissues and bronchoalveolar lavage fluid(BALF)within 12 hours after the last atomization.Extracting mice BALF for accounting inflammatory cells and the classification proportion,ELISA is applied to testing IL-33 concentration in BALF.The changes of pathological and airway structure of mice lung tissue with HE and PAS staining were observed.RT-PCR was used to justify the expression level of IL-33 in mice lung tissue.SPSS 16.0 was used for statistical analysis.Results Airway resistance of model group was significantly higher than control group and treatment group at three concentrations(12.5mg/L,25mg/L and 50mg/L)of methacholine(P<0.05).There is no difference between control group and treatment group(P>0.05).lung tissue inflammatory infiltration and mucus secretion from model group were indicated significantly increased by HE and PAS staining;moreover,total cellular accounts,eosinophils percentage and neutrophilic granulocyte percentage in BALF of model group increased significantly(P<0.01)than control group and treatment group.IL-33 and IL-4,IL-5,IL-13concentration of model group BALF were significant higher than control group(P<0.01,P<0.05,P<0.01,P<0.01);IL-33 and IL-4,IL-5,IL-13 concentration in BALF of treatment group was lower comparing with model group(P<0.01,P<0.05,P<0.05,P<0.05).The expression of IL-33 mRNA in mice lung tissue of model group is significant higher than control group and treatment group(P<0.01).The expression of lung tissue IL-33mRNA in treatment group was lower than model group(P<0.05).The expression of IL-33mRNA in lung tissue was positively correlated with the following three factors,total accounts of inflammatory cells,eosinophils percentage in BALF and the airway resistances which were measured after of stimulations with different Mch concentrations(12.5 mg/ml?25mg/ml?50 mg/ml)Conclusions Airway inflammation and airway hyperreactivity in asthma model mice were correlated with high expression of IL-33.In our experiment,the aerosol inhalation inactivated-mycobacterium phlei could reduce the secretion of type 2 cytokine in asthma mice model,reduce airway inflammation,improve airway hyperreactivity.It mightly be related to reducing the expression of IL-33 in asthma mice.