Immunologic Mechanism Of Yinghuapinggan Granule Against Influenza A/H1N1 Virus In Vivo Based On The TLRs/MyD88 Signaling Pathway

Objective An intranasal influenza virus(IFV)infection in ICR mouse was utilized as the model to study the activity of Yinghuapinggan granule(YHPG)against influenza A/H1N1 virus in vivo,and investigate the effect of YHPG on immunologic function of infected mice.Furthermore,the antiviral activity and the mechanism of immunologic function of YHPG were investigated on the basis of Toll receptors(TLRs),which could provide a scientific basis for its clinical application.Method 1.The effect of YHPG on mice with influenza viral pneumonia:Mice were randomly divided into normal control group(Normal-C),IFV-infected control group(IFV-C),ribavirin treated group,low,moderate and high dose of YHPG treated group.An intranasal influenza virus infection in ICR mouse was utilized as the model.At the 3rd and 7th day after infection,the lung index,the virus load and pathologic changes in lung tissues of mice were detected.2.The effect of YHPG on immunologic function of IFV-infected mice:At the 3rd and 7th day after infection,Flow cytometry was employed to observe the levels of CD4+,CD8+,and CD4+/CD8+in whole blood and detect the levels of IL-2,IL-4,IL-5,IFN-γ and TNF in serum.3.The effect of YHPG on the TLRs signaling pathway of IFV-infected mice:At the 3rd and 7th day after infection,TLR4,MyD88,TRAF6 and NF-κB p65 mRNA and protein expression in lung tissues of IFV-infected mice were detected by RT-PCR and immunohistochemical analysis,respectively.Results 1.YHPG could significantly decrease the virus load and lung index of IFV-infected mice,alleviate the changes of the pathology of influenza viral pneumonia,which indicated that YHPG could inhibit the influenza virus replication,alleviate pulmonary damage of IFV-infected mice.2.YHPG could significantly increase the levels of CD4+and CD4+/CD8+ ratio and reduce the levels of CD8+in whole blood,increase levels of IL-2 and IFN-γ and decrease levels of IL-4,IL-5 and TNF in serum,which indicated that YHPG could increase the immunologic function of IFV-infected mice.3.YHPG could significantly reduce the expression of TLR4,MyD88,TRAF6 and NF-κB p65 at the mRNA and protein level,which indicated that YHPG could regulate the expression of genes and proteins in TLRs signaling pathway.Conclusion YHPG has therapeutic effects on mice infected by H1N1 virus in vivo,due to its ability of alleviation of lung damage,improvement of immunologic function of infected mice,regulation of the expression of genes and proteins in TLRs signaling pathway.