[Immunoregulatory effect of Bacillus Calmette Guerin aerosol to allergic airway diseases].

OBJECTIVE: To investigate whether bacillus calmette guerin (BCG) is effective used transairway and its preventive mechanisms to allergic airway diseases. METHODS: Animal experiment was finished. Adult rats were devided into four groups: control group, ovalbumin-sensitized group, BCG used transairway group, BCG used transairway + ovalbumin-sensitized group. Then these animals symptoms were studied and the pathology change were studied under microscope about nasal and bronchi mucosa and bronchoalveolar lavege fluid cells. IL-4 mRNA and IFN-gamma mRNA in lung tissue were detected through RT-PCR, the protein production of IL-4 and IFN-gamma about bronchoalveolar lavege fluid and serum were detected through ELISA. RESULTS: In ovalbumin-sensitized group, allergic animal model were made successfully. In only BCG used transairway group, the symptoms of animals were normal, few inflammation cells infiltrated into the mucosa of nasal and bronchi, the numbers of macrophage were greatly increased in smear of bronchoalveolar lavege fluid, IFN-gamma mRNA and protein production were greatly increased. In BCG used transairway + ovalbumin-sensitized group, the allergic symptoms and inflammation were greatly reduced, not only IFN-gamma mRNA and protein production were increased but also IL-4 mRNA and protein production were greatly decreased. CONCLUSION: It is a good pathway that BCG used transairway. The immunoloregulation mechanisms of BCG to allergic airway diseases are to enhance Th1 response, in the meantime, to suppress Th2 response.