Molecular Mechanism And Medical Significance Of Herpes Simplex Virus Type Ⅰ Manipulating Tryptophan Metabolism To Promote Lytic Infectio

Background:Herpes simplex virus type Ⅰ(HSV-1)is a double-stranded envolope DNA virus.It is commonly infected in the human population and can cause diseases such as cold sores,keratoconjunctivitis,and encephalitis,resulting in a huge global healthcare burden.There is currently no vaccine on the market for HSV-1,and drug resistance has been a problem.Identifying the key signaling pathways and host factors that regulate viral replication is an important prerequisite to elucidate the pathogenesis of viral pathogenesis.This is also an important basis for developing drugs and diagnostic and therapeutic methodsTherefore,it is necessary to deeply understand the mechanism of action between HSV-1 and the host for screening new targets and developing new drugs.Methods:We firstly performed metabonomic sequencing with HSV-1 infected cells to determine whether HSV-1 infection affected tryptophan metabolism.These results were further confirmed by through transcriptome sequencing and qPCR,etc The effects of HSV-1 on tryptophan metabolism and its biological effects were analyzed by qPCR,EILSA,immunofluorescence and nuclear and plasma separation experiments.Next,we analyzed the effects of inhibition or deletion of IDO 1 and AhR,two proteins in the tryptophan metabolism pathway,on HSV-1 ICP0 and ICP27 gene transcription and viral replication by Western blots,CCID50,immunofluorescence,HE staining and other methods.Then,we explored the molecular mechanism by which AhR,a downstream molecule of tryptophan metabolism,affects viral replication through transcriptional activity analysis of promoter,ChIP,fluorescence colocalization,and Western blotting.Finally,the mouse model infected with HSV-1 was treated with AhR inhibitors to determine whether AhR can be used as a target for anti-HSV-1 virus therapy.Results:1.HSV-1 infection can manipulate host cell metabolic pathways,including tryptophan metabolism,choline metabolism and cholesterol metabolism,and affect its transcription and replication.2.HSV-1 infection activates the tryptophan metabolism IDO 1-Kyn-AhR pathway through an interferon-dependent pathway and promotes AhR entry into the nucleus.3.Targeted tryptophan metabolism IDO1-Kyn-AhR pathway can affect HSV-1 virus transcription and replication.In vitro knockout of IDO 1 or AhR gene can inhibit the transcriptional replication of HSV-1 virus.In vitro activation or inhibition of AhR can promote or weaken the transcription and replication of HSV-1 virus.AhR knockout can reduce the susceptibility of mice to HSV-1.4.Two molecular mechanisms of AhR promoting HSV-1 transcription and replication were discovered.The first is that after the activation of AhR into the nucleus,it forms a transcription complex with Cyclin T1,VP 16 and RNA Pol Ⅱ in the nucleus and binds to the upstream promoter region of the early genes ICP0 and ICP27 of HSV-1 to positively regulate the transcription of HSV-1,thus promoting the replication of HSV-1.The second is that AhR promotes the intercellular transmission of HSV-1 by up-regulating the expression of the intracellular receptor of HSV-1.5,AhR is a potential drug target for anti-HSV-1 virus therapy.After the treatment of HSV-1 infected mice with AhR inhibitor CH223191,it was found that the survival rate in the treatment group was significantly higher than that in the control group,the load of HSV-1 in all organs in the treatment group was significantly lower than that in the control group,and the degree of organ damage in the treatment group was less than that in the control group.Conclusion:This study revealed a new metabolic pathway IDO1-Kyn-AhR regulating lytic infection of HSV-1,systematically elucidated the mechanism of AhR promoting lytic infection of HSV-1,and confirmed the feasibility of using AhR as an antiviral target in mice infected with HSV-1.It provides a new candidate target for the treatment of HSV-1 related diseases.