Hantaviruses,such as Hantaan virus(HTNV)and Seoul virus,are the causative agents of Hantavirus cardiopulmonary syndrome(HCPS)and hemorrhagic fever with renal syndrome(HFRS),and are important zoonotic pathogens.China h...Hantaviruses,such as Hantaan virus(HTNV)and Seoul virus,are the causative agents of Hantavirus cardiopulmonary syndrome(HCPS)and hemorrhagic fever with renal syndrome(HFRS),and are important zoonotic pathogens.China has the highest incidence of HFRS,which is mainly caused by HTNV and Seoul virus.No approved antiviral drugs are available for these hantaviral diseases.Here,a chemiluminescence-based highthroughput-screening(HTS)assay was developed and used to screen HTNV pseudovirus(HTNVpv)inhibitors in a library of 1813 approved drugs and 556 small-molecule compounds from traditional Chinese medicine sources.We identified six compounds with in vitro anti-HTNVpvactivities in the low-micromolar range(EC50values of0.1–2.2μmol/L;selectivity index of 40–900).Among the six selected compounds,cepharanthine not only showed good anti-HTNVpvactivity in vitro but also inhibited HTNVpv-fluc infection in Balb/c mice 5 h after infection by94%(180 mg/kg/d,P<0.01),93%(90 mg/kg/d,P<0.01),or 92%(45 mg/kg/d,P<0.01),respectively,in a bioluminescent imaging mouse model.A time-of-addition analysis suggested that the antiviral mechanism of cepharanthine involves the membrane fusion and entry phases.Overall,we have established a HTS method for antiviral drugs screening,and shown that cepharanthine is a candidate for HCPS and HFRS therapy.These findings may offer a starting point for the treatment of patients infected with hantaviruses.展开更多
Hantavirus infection is a global health challenge,causing widespread public concern.In recent years,cases of hantavirus infection in pregnant women have been reported in many countries.The infected pregnant women and ...Hantavirus infection is a global health challenge,causing widespread public concern.In recent years,cases of hantavirus infection in pregnant women have been reported in many countries.The infected pregnant women and their fetuses appear to have more severe clinical symptoms and worse clinical outcomes.Hence,to study the prevalence of hantavirus infection in pregnant women,this study will focus on the epidemiological distribution of the virus,different virus species penetrating the placental barrier,and factors affecting the incidence and clinical outcome of the infection in pregnant women and their fetuses.In addition,this review will also discuss the diagnostic tools and treatments for pregnant patients and provide an overview of the relevant future research.展开更多
The Hantaan virus(HTNV)and Seoul virus(SEOV)mutants have accumulated over time.It is important to determine whether their neutralizing epitopes have evolved,thereby making the current vaccine powerless.However,it is i...The Hantaan virus(HTNV)and Seoul virus(SEOV)mutants have accumulated over time.It is important to determine whether their neutralizing epitopes have evolved,thereby making the current vaccine powerless.However,it is impossible to determine by using traditional plaque reduction neutralization test(PRNT),because it requires large numbers of live mutant strains.Pseudovirus-based neutralization assays(PBNA)were developed by employing vesicular stomatitis virus(VSV)backbone incorporated with HTNV or SEOV glycoproteins(VSVDG*-HTNVG or VSVDG*-SEOVG).56 and 51 single amino acid substitutions of glycoprotein(GP)in HTNV and SEOV were selected and introduced into the reference plasmid.Then the mutant pseudoviruses were generated and tested by PBNA.The PBNA results were highly correlated with PRNT ones with R2 being 0.91 for VSVDG*-HTNVG and 0.82 for VSVDG*-SEOVG.53 HTNV mutant pseudoviruses and 46 SEOV mutants were successfully generated.Importantly,by using PBNA,we found that HTNV or SEOV immunized antisera could neutralize all the corresponding 53 HTNV mutants or the 46 SEOV mutants respectively.The novel PBNA enables us to closely monitor the effectiveness of vaccines against large numbers of evolving HTNV and SEOV.And the current vaccine remains to be effective for the naturally occurring mutants.展开更多
Hantaan virus(HTNV)is a rodent-borne virus that causes hemorrhagic fever with renal syndrome(HFRS),resulting in a high mortality rate of 15%.Interferons(IFNs)play a critical role in the anti-hantaviral immune response...Hantaan virus(HTNV)is a rodent-borne virus that causes hemorrhagic fever with renal syndrome(HFRS),resulting in a high mortality rate of 15%.Interferons(IFNs)play a critical role in the anti-hantaviral immune response,and IFN pretreatment efficiently restricts HTNV infection by triggering the expression of a series of IFNstimulated genes(ISGs)through the Janus kinase-signal transducer and activator of transcription 1(JAK-STAT)pathway.However,the tremendous amount of IFNs produced during late infection could not restrain HTNV replication,and the mechanism remains unclear.Here,we demonstrated that receptor-interacting protein kinase 3(RIPK3),a crucial molecule that mediates necroptosis,was activated by HTNV and contributed to hantavirus evasion of IFN responses by inhibiting STAT1 phosphorylation.RNA-seq analysis revealed the upregulation of multiple cell death-related genes after HTNV infection,with RIPK3 identified as a key modulator of viral replication.RIPK3 ablation significantly enhanced ISGs expression and restrained HTNV replication,without affecting the expression of pattern recognition receptors(PRRs)or the production of type I IFNs.Conversely,exogenously expressed RIPK3 compromised the host's antiviral response and facilitated HTNV replication.RIPK3^(-/-)mice also maintained a robust ability to clear HTNV with enhanced innate immune responses.Mechanistically,we found that RIPK3 could bind STAT1 and inhibit STAT1 phosphorylation dependent on the protein kinase domain(PKD)of RIPK3 but not its kinase activity.Overall,these observations demonstrated a noncanonical function of RIPK3 during viral infection and have elucidated a novel host innate immunity evasion strategy utilized by HTNV.展开更多
Hantaan virus(HTNV),the prototype virus of hantavirus,could escape innate immunity by restraining type I interferon(IFN)responses.It is largely unknown whether there existed other efficient anti-hantaviral tactics in ...Hantaan virus(HTNV),the prototype virus of hantavirus,could escape innate immunity by restraining type I interferon(IFN)responses.It is largely unknown whether there existed other efficient anti-hantaviral tactics in host cells.Here,we demonstrate that the stimulator of interferon genes(STING)strengthens the host IFNindependent anti-hantaviral immunity.HTNV infection activates RIG-I through IRE1-XBP 1-mediated ER stress,which further facilitates the subcellular translocation and activation of STING.During this process,STING triggers cellular autophagy by interacting with Rab7A,thus restricting viral replication.To note,the anti-hantaviral effects of STING are independent of canonical IFN signaling.Additionally,neither application of the pharmacological antagonist nor the agonist targeting STING could improve the outcomes of nude mice post HTNV challenge in vivo.However,the administration of plasmids exogenously expressing the mutant C-terminal tail(ΔCTT)STING,which would not trigger the type I IFN responses,protected the nude mice from lethal HTNV infection.In summary,our research revealed a novel antiviral pathway through the RIG-I-STING-autophagy pathway,which offered novel therapeutic strategies against hantavirus infection.展开更多
基金National Science and Technology Major Projects of Infectious Disease(grant number 2018ZX10731101)。
文摘Hantaviruses,such as Hantaan virus(HTNV)and Seoul virus,are the causative agents of Hantavirus cardiopulmonary syndrome(HCPS)and hemorrhagic fever with renal syndrome(HFRS),and are important zoonotic pathogens.China has the highest incidence of HFRS,which is mainly caused by HTNV and Seoul virus.No approved antiviral drugs are available for these hantaviral diseases.Here,a chemiluminescence-based highthroughput-screening(HTS)assay was developed and used to screen HTNV pseudovirus(HTNVpv)inhibitors in a library of 1813 approved drugs and 556 small-molecule compounds from traditional Chinese medicine sources.We identified six compounds with in vitro anti-HTNVpvactivities in the low-micromolar range(EC50values of0.1–2.2μmol/L;selectivity index of 40–900).Among the six selected compounds,cepharanthine not only showed good anti-HTNVpvactivity in vitro but also inhibited HTNVpv-fluc infection in Balb/c mice 5 h after infection by94%(180 mg/kg/d,P<0.01),93%(90 mg/kg/d,P<0.01),or 92%(45 mg/kg/d,P<0.01),respectively,in a bioluminescent imaging mouse model.A time-of-addition analysis suggested that the antiviral mechanism of cepharanthine involves the membrane fusion and entry phases.Overall,we have established a HTS method for antiviral drugs screening,and shown that cepharanthine is a candidate for HCPS and HFRS therapy.These findings may offer a starting point for the treatment of patients infected with hantaviruses.
基金supported by the National Scientific Research Program of China:New technology and project on intervention and elimination of cytokine storm and secondary infection in acute severe respiratory infectious diseases(2017ZX10204401-002-005)。
文摘Hantavirus infection is a global health challenge,causing widespread public concern.In recent years,cases of hantavirus infection in pregnant women have been reported in many countries.The infected pregnant women and their fetuses appear to have more severe clinical symptoms and worse clinical outcomes.Hence,to study the prevalence of hantavirus infection in pregnant women,this study will focus on the epidemiological distribution of the virus,different virus species penetrating the placental barrier,and factors affecting the incidence and clinical outcome of the infection in pregnant women and their fetuses.In addition,this review will also discuss the diagnostic tools and treatments for pregnant patients and provide an overview of the relevant future research.
基金supported by the National Science and Technology Major Projects of Drug Discovery[Grant Number 2018ZX09101-001]
文摘The Hantaan virus(HTNV)and Seoul virus(SEOV)mutants have accumulated over time.It is important to determine whether their neutralizing epitopes have evolved,thereby making the current vaccine powerless.However,it is impossible to determine by using traditional plaque reduction neutralization test(PRNT),because it requires large numbers of live mutant strains.Pseudovirus-based neutralization assays(PBNA)were developed by employing vesicular stomatitis virus(VSV)backbone incorporated with HTNV or SEOV glycoproteins(VSVDG*-HTNVG or VSVDG*-SEOVG).56 and 51 single amino acid substitutions of glycoprotein(GP)in HTNV and SEOV were selected and introduced into the reference plasmid.Then the mutant pseudoviruses were generated and tested by PBNA.The PBNA results were highly correlated with PRNT ones with R2 being 0.91 for VSVDG*-HTNVG and 0.82 for VSVDG*-SEOVG.53 HTNV mutant pseudoviruses and 46 SEOV mutants were successfully generated.Importantly,by using PBNA,we found that HTNV or SEOV immunized antisera could neutralize all the corresponding 53 HTNV mutants or the 46 SEOV mutants respectively.The novel PBNA enables us to closely monitor the effectiveness of vaccines against large numbers of evolving HTNV and SEOV.And the current vaccine remains to be effective for the naturally occurring mutants.
基金This work was supported in whole or in part by the National Natural Science Foundation of China(82172272,31970148 and 82222367)the Key Research and Development Program of Shaanxi(2021ZDLSF01-05 and 2021ZDLSF01-02).
文摘Hantaan virus(HTNV)is a rodent-borne virus that causes hemorrhagic fever with renal syndrome(HFRS),resulting in a high mortality rate of 15%.Interferons(IFNs)play a critical role in the anti-hantaviral immune response,and IFN pretreatment efficiently restricts HTNV infection by triggering the expression of a series of IFNstimulated genes(ISGs)through the Janus kinase-signal transducer and activator of transcription 1(JAK-STAT)pathway.However,the tremendous amount of IFNs produced during late infection could not restrain HTNV replication,and the mechanism remains unclear.Here,we demonstrated that receptor-interacting protein kinase 3(RIPK3),a crucial molecule that mediates necroptosis,was activated by HTNV and contributed to hantavirus evasion of IFN responses by inhibiting STAT1 phosphorylation.RNA-seq analysis revealed the upregulation of multiple cell death-related genes after HTNV infection,with RIPK3 identified as a key modulator of viral replication.RIPK3 ablation significantly enhanced ISGs expression and restrained HTNV replication,without affecting the expression of pattern recognition receptors(PRRs)or the production of type I IFNs.Conversely,exogenously expressed RIPK3 compromised the host's antiviral response and facilitated HTNV replication.RIPK3^(-/-)mice also maintained a robust ability to clear HTNV with enhanced innate immune responses.Mechanistically,we found that RIPK3 could bind STAT1 and inhibit STAT1 phosphorylation dependent on the protein kinase domain(PKD)of RIPK3 but not its kinase activity.Overall,these observations demonstrated a noncanonical function of RIPK3 during viral infection and have elucidated a novel host innate immunity evasion strategy utilized by HTNV.
基金supported by grants from the National Natural Science Foundation of China (No.31970148,82172272 and 82202367)the Key Research and Development Program of Shaanxi (2021ZDLSF01-02 and 2021ZDLSF01-05).
文摘Hantaan virus(HTNV),the prototype virus of hantavirus,could escape innate immunity by restraining type I interferon(IFN)responses.It is largely unknown whether there existed other efficient anti-hantaviral tactics in host cells.Here,we demonstrate that the stimulator of interferon genes(STING)strengthens the host IFNindependent anti-hantaviral immunity.HTNV infection activates RIG-I through IRE1-XBP 1-mediated ER stress,which further facilitates the subcellular translocation and activation of STING.During this process,STING triggers cellular autophagy by interacting with Rab7A,thus restricting viral replication.To note,the anti-hantaviral effects of STING are independent of canonical IFN signaling.Additionally,neither application of the pharmacological antagonist nor the agonist targeting STING could improve the outcomes of nude mice post HTNV challenge in vivo.However,the administration of plasmids exogenously expressing the mutant C-terminal tail(ΔCTT)STING,which would not trigger the type I IFN responses,protected the nude mice from lethal HTNV infection.In summary,our research revealed a novel antiviral pathway through the RIG-I-STING-autophagy pathway,which offered novel therapeutic strategies against hantavirus infection.
