To elucidate the impact of interferon regulatory factors(IRFs)on the proliferation of porcine pseudorabies virus(PRV),this study utilized shRNA technology to establish a PK15 cell line with the targeted knockdown of IRF1-9 genes.The knockdown efficiency was verified,and the proliferation of PRV subsequent to the knockdown was assessed using flow cytometry and titration assays.Additionally,the mRNA expression levels of PRV-gB,IFN-β,ISG-15,and IL-6 in PRV-infected cells were quantified by reverse transcription quantitative polymerase chain reaction(RT-qPCR).The expression of the gB protein in PRV-infected cells was analyzed by Western blotting.The knockdown efficiency assay demonstrated a significant reduction in the expression of IRF1-9 mRNA in PK15 cells.The results from flow cytometry and titration assays indicated that the knockdown of IRF1-9 genes facilitated the proliferation of PRV.Furthermore,RT-qPCR and Western blot results revealed a significant increase in the mRNA and protein expression levels of PRV-gB following the knockdown of IRF1-9 genes.The analysis of mRNA expression levels of cellular inflammatory factors showed that the knockdown of IRF1-9 inhibited the PRV-induced expression of IFN-β,ISG-15,and IL-6 at the mRNA level.In conclusion,these findings suggest that IRF1-9 serves as a host restriction factor,limiting the replication of PRV within PK-15 cells.