Silencing ZafA Gene On The Impact Of Growth And Virulence In Aspergillus Fumigatus

Objective Through RNAi,investigating ZafA gene contributions to aspergillus fumigatus' virulence and growth,to find out a new method to treat pulmonary aspergillosis.Methods Useing chemical synthesis the siRNA,transform aspergillus fumigatus with synthetic siRNA by electroporation.Extract the total mRNA of aspergillus fumigatus. Performing RT-PCR,observe the change in mRNA level and analyze the gene whether or not be silenced.Infect the immunosuppressed BALB/c mouse intranasally with 2×10~7cm(-1) aspergillus fumigatus,thought G-test result,observe the mouce' mortality and the lung pathological section change,to learn the aspergillus aspergillus growth and virulence.Put the lung tissue in culture.Results(1)After electroporation,the siRNA intervention group aspergillus fumigatus's ZafA gene mRNA ZafA/18srRNA is 0.533±0.026,compare with the missense chain group 1.098±0.027 and the PBS contrast group 1.082±0.012 is obviously reduced(P＜0.05);(2) The siRNA intervention group aspergillus fumigatus grows on culture medium compare with the missense chain group and the PBS contrast group are obviously restricted(P＜0.05). (3)Immunity index:IgG is 0.69±0.04,0.33±0.07(P＜0.05);IgA 0.71±0.05,0.51±0.06 (P＜0.05);IgM 1.41±0.08,1.04±0.10(P＜0.05).(4) G-Test detection(1-3)-β-D-gluca, the siRNA intervention group is 14.9±3.71pg/ml,compare with the missense chain group 43.6±4.68 pg/ml,the PBS contrast group 42.8±4.61 pg/ml is obviously reduced(P＜0.05) (5) In vivo experiments show the siRNA intervention group 2mouse are dead,the mortality is 6.3%,the missense chain group 16 mouse are dead,the mortality is 53.3%,the PBS contrast group 15 mouse are dead,the mortality is 50%.The lung pathological section indicates that the siRNA intervention group is less damaged than the missense chain group and the PBS contrast group.Survival analysis indicates the siRNA intervention group'mouse live longer than the missense chain group and the PBS contrast group.The siRNA intervention group don't have aspergillus fumigatus grow in the Medium,but the other groups have aspergillus fumigatus growth.Conclusion The ZafA gene is essential for the fungal virulence and growth of aspergillus fumigatus in the tissues of immunosuppressed mice.RNAi can be to the new way to treat the Pulmonary fungal infections.