Fibroblast growth factor 11 inhibits foot-and-mouth disease virus gene expression and replication in vitro

Foot-and-mouth disease virus (FMDV) causes highly contagious disease of cloven-hoofed animals such as cattle, swine, and sheep. Although FMD vaccine is the traditional way to protect against the disease, the use of FMD vaccines to protect early infection is limited. The alternative strategy of applying antiviral agents is required to control the spread of FMDV in outbreak situations. Fibroblast growth factor 11 (FGF11) is a member of the intracellular FGF. Here, we identified the inhibitory effect of FGF11 on FMDV gene expression through the transcriptional and translational regulation. For the quantitative analysis of FMDV transcription/translation level, we firstly constructed a plasmid reporter system (FMDV five prime untranslated region (5' UTR) -luci) conjugating luciferase encoding gene with FMDV 5' UTR region, which is a non-coding region to control FMDV transcription/translation and includes cis-acting replication element (CRE) and internal ribosome entry site (IRES). FGF11 decreased the gene expression of FMDV 5' UTR-luci reporter in a dose-dependent manner. We further confirmed the inhibitory function of FGF11 on FMDV gene expression a replication in the FMDV-infected pig cells. FGF11 expression inhibited RNA production of FMDV RNA polymerase 3D gene in the FMDV-infected cells. In addition, while FMDV cell infection induced cytopathic effect (CPE) within 24 hr, FGF11 expression dramatically repressed CPE at the basal level. These results indicate that FGF11 inhibits FMDV gene expression and replication in vitro, implicating to provide intervention strategy for FMDV pathogenesis and transmission.