The Experimental Study About Effects Of BCG Treatment On Stem Cell Factor And Macrophage Colony-stimulating Factor In Asthma

ObjectiveTo observe the expressions of stem cell factor (SCF) and macrophage colony-stimulating factor (M-CSF) and IL-12 of asthmatic mice and effects of bacillus calmette-guerin(BCG) treatment on them.Methods30 male Kunming mice were randomly divided into three groups,with 10 mice in each group.①Asthmatic group:each mouse was sensitized by intraperitoneal injection 10μg ovalbumin(OVA) and 1mg aluminum hydroxide,and challenged by inhaling aerosol 1%OVA to establish asthma model.②BCG treatment group:each mouse was sensitized and challenged in the same methods as asthmatic group and was intradermal injection with BCG 0.025mg on 7,3,1 day before sensitization.③Control group:mice were sensitized and challenged with NS.Twenty-four hours after the final challenge, bronchoalveolar lavage fluid(BALF) was collected.The total number of cells and eosinophils in BALF was counted.The levels of SCF,M-CSF and IL-12 were determined using Enzyme-Linked Immunosorbent Assay (ELISA).Sections from lung tissue were stained with HE.The expressions of SCF and M-CSF in lung tissue were measured by immunohistochemistry technique and computerized image analysis system.Results1.There are many inflammatory cells infiltrate into lung tissue in asthmatic group.Compared with asthmatic group,the inflammatory cells were reduced markedly in BCG treatment group.There is no infiltration of inflammatory cells in control group. 2.The number of total cells and EOS in BALF of asthmatic group and BCG treatment group was more than that of control group.Compared with asthmatic group,the number of total cells and EOS in BCG treatment group was reduced.3.Compared with control group,the expressions of SCF in lung tissue and BALF increased significantly in asthmatic group,There were no significant difference between BCG treatment group and asthmatic group.A positive correlation between SCF level and the number of EOS of BALF in asthmatic group.4.The expressions of M-CSF in lung tissue and BALF increased noticeably in asthmatic group than that in control group,and decreased in BCG treatment group compared with asthmatic group.5.Asthmatic group has lower IL-12 level than that in control group.The IL-12 level of BCG treatment group was increased compared with asthmatic group.A negative correlation between IL-12 level and M-CSF of BALF in asthmatic group or BCG treatment group. 6.The SCF and M-CSF can be detected in bone marrow of three groups.But there were no difference among three groups.Conclusion1.BCG treatment in early can markedly inhibit the EOS infiltration in airway of asthmatic mice.But it can not completely eliminate the airway inflammation.2.The expressions of SCF and M-CSF were increased in lung tissue and BALF of asthmatic mice.SCF or M-CSF take part in the development of allergic inflammatory.3.BCG has anti-inflammatory effect on airway inflammation of asthmatic mice by promoting the expression of IL-12 and inhibiting the expression of M-CSF.4.The were no difference in SCF or M-CSF of the bone marrow.SCF or M-CSF in location of lung in asthmatic mice maybe play important effects..