Dear Editor,Enterovirus 71(EV71)is the main pathogen of hand,foot,and mouth disease(HFMD),which is a serious public health threat,especially in the Asia-Pacific region(Wu et al.,2013).Due to the lack of effective anti...Dear Editor,Enterovirus 71(EV71)is the main pathogen of hand,foot,and mouth disease(HFMD),which is a serious public health threat,especially in the Asia-Pacific region(Wu et al.,2013).Due to the lack of effective antivirals for treatment,supportive therapy remains to be the primary measure for severe infections of EV71.EV71 belongs to the genus Enterovirus in the family of Picornavirridae.EV71 encodes a polyprotein that is proteolytically cleaved into four structural proteins and seven nonstructural proteins,i.e.,VP1 to VP4,2A to 2C,and 3A to 3D.Moreover,an alternative encoding strategy of harboring a novel open reading frame encoding a short peptide has been recently reported in gut epithelial cells infected with some enteroviruses(Lulla et al.,2019).Structural proteins play a key role in the packaging and maturation of virus particles,while non-structural proteins are mainly involved in the replication process of virus.Among them,the 3D polymerase(3Dpol)protein functions as an RNA-dependent RNA polymerase(RdRP)that is essential for viral RNA synthesis(Wu et al.,2010).展开更多
Hand,foot,and mouth disease(HFMD)is a common pediatric illness mainly caused by enteroviruses,which are important human pathogens.Currently,there are no available antiviral agents for the therapy of enterovirus infect...Hand,foot,and mouth disease(HFMD)is a common pediatric illness mainly caused by enteroviruses,which are important human pathogens.Currently,there are no available antiviral agents for the therapy of enterovirus infection.In this study,an excellent high-content antiviral screening system utilizing the EV-A71-eGFP reporter virus was developed.Using this screening system,we screened a drug library containing 1042 natural compounds to identify potential EV-A71 inhibitors.Fangchinoline(FAN),a bis-benzylisoquinoline alkaloid,exhibits potential inhibitory effects against various enteroviruses that cause HFMD,such as EV-A71,CV-A10,CV-B3 and CV-A16.Further investigations revealed that FAN targets the early stage of the enterovirus life cycle.Through the selection of FAN-resistant EV-A71 viruses,we demonstrated that the VP1 protein could be a potential target of FAN,as two mutations in VP1(E145G and V258I)resulted in viral resistance to FAN.Our research suggests that FAN is an efficient inhibitor of EV-A71 and has the potential to be a broad-spectrum antiviral drug against human enteroviruses.展开更多
Dear editor,Ebola virus(EBOV)is a member of the genus Orthoebolavirus within the family of Filoviridae.It's the causative agent of Ebola virus disease(EVD),characterized by general malaise,severe gastrointestinal ...Dear editor,Ebola virus(EBOV)is a member of the genus Orthoebolavirus within the family of Filoviridae.It's the causative agent of Ebola virus disease(EVD),characterized by general malaise,severe gastrointestinal illness,febrile,coagulopathy,multi-organs dysfunction,and high mortality(up to 90%)in humans and nonhuman primates(NHPs)(Jacob et al.,2020).Since its discovery in 1976,EBOV has grabbed the global concerns,especially after the West African epidemic from 2014 to 2016,which resulted in 30,000 cases and over 11,000 deaths(Feldmann et al.,2020;Jacob et al.,2020).From 2018 to 2022,there have been thousands of infections primarily in the Democratic Republic of the Congo(DRC),resulting in over 2000 deaths.This highlights the importance of continued attention and ongoing surveillance(www.who.int/emergenci es/disease-outbreak-news).展开更多
Chikungunya virus(CHIKV) is a mosquito-borne alphavirus. As an emerging virus, CHIKV imposes a threat to public health. Currently, there are no vaccines or antivirals available for the prevention of CHIKV infection. L...Chikungunya virus(CHIKV) is a mosquito-borne alphavirus. As an emerging virus, CHIKV imposes a threat to public health. Currently, there are no vaccines or antivirals available for the prevention of CHIKV infection. Lycorine, an alkaloid from Amaryllidaceae plants, has antiviral activity against a number of viruses such as coronavirus, flavivirus and enterovirus. In this study, we found that lycorine could inhibit CHIKV in cell culture at a concentration of 10 lmol/L without apparent cytotoxicity. In addition, it exhibited broad-spectrum anti-alphavirus activity, including Sindbis virus(SINV),Semliki Forest virus(SFV), and Venezuelan equine encephalomyelitis virus(VEEV). The time of addition studies indicated that lycorine functions at an early post-entry stage of CHIKV life cycle. The results based on two different CHIKV replicons provided further evidence that lycorine exerts its antiviral activity mainly by inhibiting CHIKV translation.Overall, our study extends the antiviral spectrum of lycorine.展开更多
The chikungunya virus(CHIKV) is a mosquito-transmitted alphavirus, which has infected millions of people in Africa, Asia, Americas, and Europe since it reemerged in India and Indian Ocean regions in 2005–2006. Starti...The chikungunya virus(CHIKV) is a mosquito-transmitted alphavirus, which has infected millions of people in Africa, Asia, Americas, and Europe since it reemerged in India and Indian Ocean regions in 2005–2006. Starting in the middle of November 2016, CHIKV has been widely spread, and more than 4,000 cases of infections in humans were confirmed in Pakistan. Here, we report the first isolation and characterization of CHIKV from the Pakistan outbreak. Eight CHIKV strains were newly isolated from human serum samples using a cell culture procedure. A full-length genome sequence and eight complete envelope(E1) sequences of CHIKV from Pakistan were obtained in this study. Alignment of the CHIKV E1 sequences revealed that the eight new CHIKV isolates were highly homogeneous, with only two nonsynonymous substitutions found at generally conserved sites(E99 and Q235). Based on the comparison of 342 E1 sequences, the two nonsynonymous mutations were located in well-recognized domains associated with viral functions such as the cell fusion and vector specificity, suggesting their potential functional importance. Phylogenetic analysis indicated that the CHIKV strains from Pakistan originated from CHIKV circulating in the Indian region. This study helps elucidate the epidemics of CHIKV in Pakistan and also provides a foundation for studies of evolution and expansion of CHIKV in South Asia.展开更多
Alphaviruses,which contain a variety of mosquito-borne pathogens,are important pathogens of emerging/reemerging infectious diseases and potential biological weapons.Currently,no specific antiviral drugs are available ...Alphaviruses,which contain a variety of mosquito-borne pathogens,are important pathogens of emerging/reemerging infectious diseases and potential biological weapons.Currently,no specific antiviral drugs are available for the treatment of alphaviruses infection.For most highly pathogenic alphaviruses are classified as risk group-3 agents,the requirement of biosafety level 3(BSL-3)facilities limits the live virus-based antiviral study.To facilitate the antiviral development of alphaviruses,we developed a high throughput screening(HTS)platform based on a recombinant Semliki Forest virus(SFV)which can be manipulated in BSL-2 laboratory.Using the reverse genetics approach,the recombinant SFV and SFV reporter virus expressing eGFP(SFV-eGFP)were successfully rescued.The SFV-eGFP reporter virus exhibited robust eGFP expression and remained relatively stable after four passages in BHK-21 cells.Using a broad-spectrum alphavirus inhibitor ribavirin,we demonstrated that the SFV-eGFP can be used as an effective tool for antiviral study.The SFV-eGFP reporter virus-based HTS assay in a 96-well format was then established and optimized with a robust Z0 score.A section of reference compounds that inhibit highly pathogenic alphaviruses were used to validate that the SFV-eGFP reporter virus-based HTS assay enables rapid screening of potent broad-spectrum inhibitors of alphaviruses.This assay provides a safe and convenient platform for antiviral study of alphaviruses.展开更多
Dear Editor,Omsk hemorrhagic fever virus(OHFV)belongs to the tickborne virus group within Flavivirus,in Flaviviridae family(Holbrook et al.2005)which consists of several important human pathogens including tick-borne ...Dear Editor,Omsk hemorrhagic fever virus(OHFV)belongs to the tickborne virus group within Flavivirus,in Flaviviridae family(Holbrook et al.2005)which consists of several important human pathogens including tick-borne encephalitis virus(TBEV),Powassan virus(POWV),Louping ill virus(LIV),Langat virus(LGTV)and Kyasnaur Forest disease virus(KFDV)(Yoshii and Holbrook 2009).OHFV is an enveloped virus containing a single-stranded positive-sense RNA genome of approximately 11,000 nucleotides.The genome has a single open reading frame,which encodes three structural proteins[capsid(C),pre-membrane(prM)or membrane(M),and envelop(E)]and seven non-structural proteins(NS1,NS2a,NS2b,NS3,NS4a,NS4b and NS5)between the 5'untranslated region(UTR)and 3'UTR(Chambers et al.1990).展开更多
The lung is the prophylaxis target against SARS-CoV-2 infection,and neutralizing antibodies are a leading class of biological products against various infectious viral pathogen.In this study,we develop a safe and cost...The lung is the prophylaxis target against SARS-CoV-2 infection,and neutralizing antibodies are a leading class of biological products against various infectious viral pathogen.In this study,we develop a safe and cost-effective platform to express neutralizing antibody in the lung with replicating mRNA basing on alphavirus replicon particle(VRP)delivery system,to prevent SARS-CoV-2 infections.First,a modified VEEV replicon with two subgenomic(sg)promoters was engineered to translate the light and heavy chains of antibody simultaneously,for expression and assembly of neutralizing anti-SARS-CoV-2 antibody CB6.Second,the feasibility and protective efficacy of replicating mRNA against SARS-CoV-2 infection were demonstrated through both in vitro and in vivo assays.The lung target delivery with the help of VRP system resulted in efficiently block SARS-CoV-2 infection with reducing viral titer and less tissue damage in the lung of mice.Overall,our data suggests that expressing neutralizing antibodies in the lungs with the help of self-replicating mRNA could potentially be a promising prophylaxis approach against SARS-CoV-2 infection.展开更多
Dear Editor,The prolonged outbreak and spread of coronavirus disease 2019(COVID-19),caused by SARS-CoV-2 poses a great threat to global economic and public health.The protective efficacy of the vaccines based on the s...Dear Editor,The prolonged outbreak and spread of coronavirus disease 2019(COVID-19),caused by SARS-CoV-2 poses a great threat to global economic and public health.The protective efficacy of the vaccines based on the spike protein(S)of SARS-CoV-2 has been compromised by the emergence of variants of concern(VOC).展开更多
Dear Editor,The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continues to disrupt global public health since its first report in December 2019,resulting in more than 380 billi...Dear Editor,The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continues to disrupt global public health since its first report in December 2019,resulting in more than 380 billion confirmed cases including nearly 5.7 billion deaths worldwide(https://covidl9.who.int).展开更多
基金supported by Hubei Provincial Natural Science Foundation of China(2025AFB822)National Key Research and Development Program of China(No.2022YFD1800100)National Natural Science Foundation of China(32100110).
文摘Dear Editor,Enterovirus 71(EV71)is the main pathogen of hand,foot,and mouth disease(HFMD),which is a serious public health threat,especially in the Asia-Pacific region(Wu et al.,2013).Due to the lack of effective antivirals for treatment,supportive therapy remains to be the primary measure for severe infections of EV71.EV71 belongs to the genus Enterovirus in the family of Picornavirridae.EV71 encodes a polyprotein that is proteolytically cleaved into four structural proteins and seven nonstructural proteins,i.e.,VP1 to VP4,2A to 2C,and 3A to 3D.Moreover,an alternative encoding strategy of harboring a novel open reading frame encoding a short peptide has been recently reported in gut epithelial cells infected with some enteroviruses(Lulla et al.,2019).Structural proteins play a key role in the packaging and maturation of virus particles,while non-structural proteins are mainly involved in the replication process of virus.Among them,the 3D polymerase(3Dpol)protein functions as an RNA-dependent RNA polymerase(RdRP)that is essential for viral RNA synthesis(Wu et al.,2010).
基金funded by Guangzhou Municipal Science and Technology Project(202102020241)the National Natural Science Foundation of China(32100110 and 32300132)the National Key Research and Development Program of China(2021YFC2701800,2021YFC2701801).
文摘Hand,foot,and mouth disease(HFMD)is a common pediatric illness mainly caused by enteroviruses,which are important human pathogens.Currently,there are no available antiviral agents for the therapy of enterovirus infection.In this study,an excellent high-content antiviral screening system utilizing the EV-A71-eGFP reporter virus was developed.Using this screening system,we screened a drug library containing 1042 natural compounds to identify potential EV-A71 inhibitors.Fangchinoline(FAN),a bis-benzylisoquinoline alkaloid,exhibits potential inhibitory effects against various enteroviruses that cause HFMD,such as EV-A71,CV-A10,CV-B3 and CV-A16.Further investigations revealed that FAN targets the early stage of the enterovirus life cycle.Through the selection of FAN-resistant EV-A71 viruses,we demonstrated that the VP1 protein could be a potential target of FAN,as two mutations in VP1(E145G and V258I)resulted in viral resistance to FAN.Our research suggests that FAN is an efficient inhibitor of EV-A71 and has the potential to be a broad-spectrum antiviral drug against human enteroviruses.
文摘Dear editor,Ebola virus(EBOV)is a member of the genus Orthoebolavirus within the family of Filoviridae.It's the causative agent of Ebola virus disease(EVD),characterized by general malaise,severe gastrointestinal illness,febrile,coagulopathy,multi-organs dysfunction,and high mortality(up to 90%)in humans and nonhuman primates(NHPs)(Jacob et al.,2020).Since its discovery in 1976,EBOV has grabbed the global concerns,especially after the West African epidemic from 2014 to 2016,which resulted in 30,000 cases and over 11,000 deaths(Feldmann et al.,2020;Jacob et al.,2020).From 2018 to 2022,there have been thousands of infections primarily in the Democratic Republic of the Congo(DRC),resulting in over 2000 deaths.This highlights the importance of continued attention and ongoing surveillance(www.who.int/emergenci es/disease-outbreak-news).
基金This work was supported by the National Key Research and Development Program of China(2018YFA0507201)。
文摘Chikungunya virus(CHIKV) is a mosquito-borne alphavirus. As an emerging virus, CHIKV imposes a threat to public health. Currently, there are no vaccines or antivirals available for the prevention of CHIKV infection. Lycorine, an alkaloid from Amaryllidaceae plants, has antiviral activity against a number of viruses such as coronavirus, flavivirus and enterovirus. In this study, we found that lycorine could inhibit CHIKV in cell culture at a concentration of 10 lmol/L without apparent cytotoxicity. In addition, it exhibited broad-spectrum anti-alphavirus activity, including Sindbis virus(SINV),Semliki Forest virus(SFV), and Venezuelan equine encephalomyelitis virus(VEEV). The time of addition studies indicated that lycorine functions at an early post-entry stage of CHIKV life cycle. The results based on two different CHIKV replicons provided further evidence that lycorine exerts its antiviral activity mainly by inhibiting CHIKV translation.Overall, our study extends the antiviral spectrum of lycorine.
基金supported by International Cooperation on key Technologies of Biosafety along the China–Pakistan Economic Corridor(153B42KYSB20170004)Major State Basic Research Development Program(2013FY 113500)the National Natural Science Foundation of China(81572003 and 31600141)
文摘The chikungunya virus(CHIKV) is a mosquito-transmitted alphavirus, which has infected millions of people in Africa, Asia, Americas, and Europe since it reemerged in India and Indian Ocean regions in 2005–2006. Starting in the middle of November 2016, CHIKV has been widely spread, and more than 4,000 cases of infections in humans were confirmed in Pakistan. Here, we report the first isolation and characterization of CHIKV from the Pakistan outbreak. Eight CHIKV strains were newly isolated from human serum samples using a cell culture procedure. A full-length genome sequence and eight complete envelope(E1) sequences of CHIKV from Pakistan were obtained in this study. Alignment of the CHIKV E1 sequences revealed that the eight new CHIKV isolates were highly homogeneous, with only two nonsynonymous substitutions found at generally conserved sites(E99 and Q235). Based on the comparison of 342 E1 sequences, the two nonsynonymous mutations were located in well-recognized domains associated with viral functions such as the cell fusion and vector specificity, suggesting their potential functional importance. Phylogenetic analysis indicated that the CHIKV strains from Pakistan originated from CHIKV circulating in the Indian region. This study helps elucidate the epidemics of CHIKV in Pakistan and also provides a foundation for studies of evolution and expansion of CHIKV in South Asia.
基金supported by the Creative Research Group Program of Natural Science Foundation of Hubei Province (2022CFA021)National Natural Science Foundation of China (81702005).
文摘Alphaviruses,which contain a variety of mosquito-borne pathogens,are important pathogens of emerging/reemerging infectious diseases and potential biological weapons.Currently,no specific antiviral drugs are available for the treatment of alphaviruses infection.For most highly pathogenic alphaviruses are classified as risk group-3 agents,the requirement of biosafety level 3(BSL-3)facilities limits the live virus-based antiviral study.To facilitate the antiviral development of alphaviruses,we developed a high throughput screening(HTS)platform based on a recombinant Semliki Forest virus(SFV)which can be manipulated in BSL-2 laboratory.Using the reverse genetics approach,the recombinant SFV and SFV reporter virus expressing eGFP(SFV-eGFP)were successfully rescued.The SFV-eGFP reporter virus exhibited robust eGFP expression and remained relatively stable after four passages in BHK-21 cells.Using a broad-spectrum alphavirus inhibitor ribavirin,we demonstrated that the SFV-eGFP can be used as an effective tool for antiviral study.The SFV-eGFP reporter virus-based HTS assay in a 96-well format was then established and optimized with a robust Z0 score.A section of reference compounds that inhibit highly pathogenic alphaviruses were used to validate that the SFV-eGFP reporter virus-based HTS assay enables rapid screening of potent broad-spectrum inhibitors of alphaviruses.This assay provides a safe and convenient platform for antiviral study of alphaviruses.
基金This work was supported by the National Major Science and Technology Project(2018ZX10711001-006)the Wuhan Science and Technology Project(2018201261638501)。
文摘Dear Editor,Omsk hemorrhagic fever virus(OHFV)belongs to the tickborne virus group within Flavivirus,in Flaviviridae family(Holbrook et al.2005)which consists of several important human pathogens including tick-borne encephalitis virus(TBEV),Powassan virus(POWV),Louping ill virus(LIV),Langat virus(LGTV)and Kyasnaur Forest disease virus(KFDV)(Yoshii and Holbrook 2009).OHFV is an enveloped virus containing a single-stranded positive-sense RNA genome of approximately 11,000 nucleotides.The genome has a single open reading frame,which encodes three structural proteins[capsid(C),pre-membrane(prM)or membrane(M),and envelop(E)]and seven non-structural proteins(NS1,NS2a,NS2b,NS3,NS4a,NS4b and NS5)between the 5'untranslated region(UTR)and 3'UTR(Chambers et al.1990).
基金This work was supported by the National Key Research and Development Program of China(2018YFA0507201)The funders had no role in study design,data collection,and interpretation,or the decision to submit the work for publication.
文摘The lung is the prophylaxis target against SARS-CoV-2 infection,and neutralizing antibodies are a leading class of biological products against various infectious viral pathogen.In this study,we develop a safe and cost-effective platform to express neutralizing antibody in the lung with replicating mRNA basing on alphavirus replicon particle(VRP)delivery system,to prevent SARS-CoV-2 infections.First,a modified VEEV replicon with two subgenomic(sg)promoters was engineered to translate the light and heavy chains of antibody simultaneously,for expression and assembly of neutralizing anti-SARS-CoV-2 antibody CB6.Second,the feasibility and protective efficacy of replicating mRNA against SARS-CoV-2 infection were demonstrated through both in vitro and in vivo assays.The lung target delivery with the help of VRP system resulted in efficiently block SARS-CoV-2 infection with reducing viral titer and less tissue damage in the lung of mice.Overall,our data suggests that expressing neutralizing antibodies in the lungs with the help of self-replicating mRNA could potentially be a promising prophylaxis approach against SARS-CoV-2 infection.
基金supported by the National Key Research and Development Program of China(2018YFA0507201).
文摘Dear Editor,The prolonged outbreak and spread of coronavirus disease 2019(COVID-19),caused by SARS-CoV-2 poses a great threat to global economic and public health.The protective efficacy of the vaccines based on the spike protein(S)of SARS-CoV-2 has been compromised by the emergence of variants of concern(VOC).
基金We thank the National Key Research and Development Program of China(2018YFA0507201)for grant support.We thank the National Virus Resource center for making Omicron available.
文摘Dear Editor,The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continues to disrupt global public health since its first report in December 2019,resulting in more than 380 billion confirmed cases including nearly 5.7 billion deaths worldwide(https://covidl9.who.int).
