Effect Of FMDV Infection On Intestinal Microflora And Type ? Interferon On FMDV Infection

As an acute and contagious disease of cloven-hoofed animals,including pigs,cattle,and sheep,Foot-and-Mouth Disease(FMD)was caused by foot-and-mouth disease virus infection,which poses a great threat to the healthy development of animal husbandry in China.However,until now,most of the studies have still focused on the pathology and etiology of foot-and-mouth disease.However,there have been few reports on the changes of intestinal flora after the host infected with FMDV.Therefore,initially,we used Illumina high-throughput sequencing technology to study the impact of foot-and-mouth disease virus infection on the intestinal microflora of suckling mice.This study found that at the portal level,compared with the control group,the foot-and-mouth disease virus infection significantly increased the species abundance of Proteobacteria in the intestine of suckling mice,and reduced the species abundance of Fusobacteria and Firmicutes.At the genus level,foot-and-mouth disease virus infection significantly reduced the species abundance of Fusobacterium compared to the control group.In order to further investigate the status of the intestinal flora in the antiviral state,type I interferons,especially the the IFN-?,?,? and IFN-?? subtypes,were studied.In recent years,studies have shown that epsilon interferon does not cause its up-regulation during acute viral infection,and its expression in FMDV infection has not been reported.In this study,a real-time quantification method for the detection of mouse epsilon interferon was established,and then the change of IFN-? in suckling mice before and after infection and at different time periods was detected.It was found for the first time that the expression of IFN-? in suckling mice before and after infection with FMDV or at different time periods was not changed significantly.This was consistent with the studies on simian monkey immunodeficiency virus,Mycobacterium tuberculosis,encephalomyelitis virus,and guaia virus.Interferon omega,delta and alphaomega showed a certain antiviral activity,but studies with FMDV have not been reported.Based on previous studies,we chose IFN-?7,IFN-?8 and IFN-?? as the subject of this study.The IFN-?7,IFN-?8 and IFN-?? was expressed in the prokaryotic expression system and purified by affinity chromatography.It was confirmed for the first time that IFN-?7,IFN-?8 and IFN-?? had anti-O/A foot-and-mouth disease virus activity.In summary,the association between foot-and-mouth disease virus(FMDV)infection and intestinal microbiota diversity and species abundance in suckling mice may be relevant,and new types of antiviral substances were found for the next step in studying the host's intestinal status under antiviral conditions.