摘要Objective:Enhancing innate immunity through interferons(IFNs)and IFN-stimulated genes(ISGs)offers a promising strategy for preventing herpes simplex virus type 1(HSV-1)infection.Prunella vulgaris L.,a medicinal herb,has demonstrated significant anti-HSV activity;in particular,its derived polysaccharide complex(PVE30)effectively inhibits viral replication.In this study,we investigate whether PVE30 exerts an anti-HSV-1 activity through activation of the innate immune response.Methods:To determine the primary stage at which PVE30 exerts its effects during the HSV-1 life cycle,plaque reduction assays were conducted.Viral infection was further assessed by investigating the DNA copies,mRNA levels and protein expression of HSV-1 in infected cells using real-time polymerase chain reaction(RT-PCR)and Western blotting.The activation of the innate immune response was evaluated by detecting mRNA levels of ISGs,including MX dynamin-like GTPase 1(Mx1),Mx2,2′-5′-oligoadenylate synthetase 1(OAS1),ISG15 and IFN regulatory factor 7(IRF7)using RT-PCR,and levels of TANK-binding kinase 1(TBK1)and IRF3 proteins using Western blotting.The translocation of phosphorylated IRF3 and stimulator of IFN genes(STING)was observed through fluorescence microscopy.Results:PVE30 pre-treatment exerted protective effects against HSV-1 infection in human immortalized keratinocytes by enhancing the innate immune response.This was shown by increased transcriptional levels of IFN-β and antiviral ISGs,along with a significant reduction in HSV-1 DNA copies,mRNA expres-sion and protein levels.Mechanistically,PVE30 promoted TBK1 phosphorylation,leading to nuclear translocation of IRF3 and subsequent IFN-β transcription;these effects were diminished by TBK1 inhibi-tor GSK8612.Additionally,STING was identified as a key mediator in PVE30-activated TBK1 signaling,as its inhibition induced by C-176 reduced PVE30's efficacy.Conclusion:This study elucidated the molecular mechanisms underlying the protective effects of PVE30 against HSV-1 infection.PVE30 exerted its protective role by enhancing STING-TBK1-IRF3 pathway-mediated innate immune response.