Ebola virus(EBOV)and Marburg virus(MARV),members of the Filoviridae family,are highly pathogenic and can cause hemorrhagic fevers,significantly impacting human society.Bats are considered reservoirs of these viruses b...Ebola virus(EBOV)and Marburg virus(MARV),members of the Filoviridae family,are highly pathogenic and can cause hemorrhagic fevers,significantly impacting human society.Bats are considered reservoirs of these viruses because related filoviruses have been discovered in bats.However,due to the requirement for maximum containment laboratories when studying infectious viruses,the characterization of bat filoviruses often relies on pseudoviruses and minigenome systems.In this study,we used RACE technology to sequence the 30-leader and 50-trailer of Mengla virus(MLAV)and constructed a minigenome.Similar to MARV,the transcription activities of the MLAV minigenome are independent of VP30.We further assessed the effects of polymorphisms at the 50 end on MLAV minigenome activity and identified certain mutations that decrease minigenome reporter efficiency,probably due to alterations in the RNA secondary structure.The reporter activity upon recombination of the 30-leaders and 50-trailers of MLAV,MARV,and EBOV with those of the homologous or heterologous minigenomes was compared and it was found that the polymerase complex and leader and trailer sequences exhibit intrinsic specificities.Additionally,we investigated whether the polymerase complex proteins from EBOV and MARV support MLAV minigenome RNA synthesis and found that the homologous system is more efficient than the heterologous system.Remdesivir efficiently inhibited MLAV as well as EBOV replication.In summary,this study provides new information on bat filoviruses and the minigenome will be a useful tool for high-throughput antiviral drug screening.展开更多
Ebola virus(EBOV) and Marburg virus(MARV),belonging to the Filoviridae family,emerged four decades ago and caused severe viral hemorrhagic fever in human and other primates.As high as 50-90% mortality,filoviruses can ...Ebola virus(EBOV) and Marburg virus(MARV),belonging to the Filoviridae family,emerged four decades ago and caused severe viral hemorrhagic fever in human and other primates.As high as 50-90% mortality,filoviruses can cause significant threats to public health.However,so far no specific and efficient vaccine has been available,nor have other treatment methods proved to be effective.It is of great importance to detect these pathogens specific,rapidly and sensitively in order to control future filovirus outbreaks.Here,recent progresses in the development of detection and diagnosis methods for EBOV and MARV are summarized.展开更多
The family Filoviridae, which includes the genera Marburgvirus and Ebolavirus, contains some of the most pathogenic viruses in humans and non-human primates （NHPs）, causing severe hemorrhagic fevers with high fatali...The family Filoviridae, which includes the genera Marburgvirus and Ebolavirus, contains some of the most pathogenic viruses in humans and non-human primates （NHPs）, causing severe hemorrhagic fevers with high fatality rates. Small animal models against filoviruses using mice, guinea pigs, hamsters, and ferrets have been developed with the goal of screening candidate vaccines and antivirals, before testing in the gold standard NHP models. In this review, we summarize the different animal models used to understand filovirus pathogenesis, and discuss the advantages and disadvantages of each model with respect to filovirus disease research.展开更多
Filoviruses are hemorrhagic fever viruses endemic to parts of Africa and the Philippines. Infection carries with it a mortality rate of up to 90% and currently there are no effective vaccines or therapeutics available...Filoviruses are hemorrhagic fever viruses endemic to parts of Africa and the Philippines. Infection carries with it a mortality rate of up to 90% and currently there are no effective vaccines or therapeutics available to combat infection. However, the filovirus virus-like particles (VLP), which are currently under development, have been shown to be a promising vaccine candidate. They provide protection from infection in the mouse, guinea pig, and nonhuman primate models of infection, eliciting high anti-glycoprotein antibody titers and T cell responses to viral proteins. In this review, we will highlight the development of the filovirus VLP and describe the current understanding of VLP immunogenicity and correlates of protection.展开更多
Filoviruses cause severe and fatal viral hemorrhagic fever in humans. Filovirus research has been extensive since the 2014 Ebola outbreak. Due to their high pathogenicity and mortality, live filoviruses require Biosaf...Filoviruses cause severe and fatal viral hemorrhagic fever in humans. Filovirus research has been extensive since the 2014 Ebola outbreak. Due to their high pathogenicity and mortality, live filoviruses require Biosafety Level-4(BSL-4) facilities, which have restricted the development of anti-filovirus vaccines and drugs.An HIV-based pseudovirus cell infection assay is widely used for viral entry studies in BSL-2 conditions. Here,we successfully constructed nine in vitro pseudo-filovirus models covering all filovirus genera and three in vivo pseudo-filovirus-infection mouse models using Ebola virus, Marburg virus, and Lloviu virus as representative viruses. The pseudo-filovirus-infected mice showed visualizing bioluminescence in a dose-dependent manner. A bioluminescence peak in mice was reached on day 5 post-infection for Ebola virus and Marburg virus and on day4 post-infection for Lloviu virus. Two known filovirus entry inhibitors, clomiphene and toremiphene, were used to validate the model. Collectively, our study shows that all genera of filoviruses can be well-pseudotyped and are infectious in vitro. The pseudo-filovirus-infection mouse models can be used for in vivo activity evaluation of anti-filovirus drugs. This sequential in vitro and in vivo evaluation system of filovirus entry inhibitors provides a secure and efficient platform for screening and assessing anti-filovirus agents in BSL-2 facilities.展开更多
Twenty-six novel tricyclic sophoridinic and matrinic derivatives containing a common chlorinated benzene fragment were designed, synthesized and evaluated for their anti-ebolavirus(EBOV)activities. Structure–activity...Twenty-six novel tricyclic sophoridinic and matrinic derivatives containing a common chlorinated benzene fragment were designed, synthesized and evaluated for their anti-ebolavirus(EBOV)activities. Structure–activity relationship analysis indicated:(i) 12 N-dichlorobenzyl motif was beneficial for the activity;(ii) the chiral configuration at C5 atom might not affect the activity much. Among the target compounds, compound 7d exhibited the most potent potency against EBOV with an IC_(50) value of 5.29 μmol/L and an SI value of over 37.8. Further in vivo anti-EBOV assay of 7d identified its high effectiveness, and in vivo anti-MARV assay of 7d suggested its inspiring broad-spectrum anti-filovirus activity. The results provided powerful information on further strategic optimization and development of this kind of compounds against filoviruses.展开更多
The development of monoclonal antibodies to treat disease caused by filoviruses,particularly Ebola virus,has risen steeply in recent years thanks to several key studies demonstrating their remarkable therapeutic poten...The development of monoclonal antibodies to treat disease caused by filoviruses,particularly Ebola virus,has risen steeply in recent years thanks to several key studies demonstrating their remarkable therapeutic potential.The increased drive to develop new and better monoclonal antibodies has necessarily seen an increase in animal model efficacy testing,which is critical to the pre-clinical development of any novel countermeasure.Primary and secondary efficacy testing against filoviruses typically makes use of one or more rodent models(mice,guinea pigs,and occasionally hamsters)or the more recently described ferret model,although the exact choice of model depends on the specific filovirus being evaluated.Indeed,no single small animal model exists for all filoviruses,and the use of any given model must consider the nature of that model as well as the nature of the therapeutic and the experimental objectives.Confirmatory evaluation,on the other hand,is performed in nonhuman primates(rhesus or cynomolgus macaques)regardless of the filovirus.In light of the number of different animal models that are currently used in monoclonal antibody efficacy testing,we sought to better understand how these efficacy tests are being performed by numerous different laboratories around the world.To this end,we review the animal models that are being used for antibody efficacy testing against filoviruses,and we highlight the challenge doses and routes of infection that are used.We also describe the various antibody treatment regimens,including antibody dose,route,and schedule of administration,that are used in these model systems.We do not identify any single best model or treatment regimen,and we do not advocate for field-wide protocol standardization.Instead,we hope to provide a comprehensive resource that will facilitate and enhance the continued pre-clinical development of novel monoclonal antibody therapeutics.展开更多
Due to their inability to generate a complete immune response, mice knockout for type I interferon （IFN） receptors （Ifnar-/-） are more susceptible to viral infections, and are thus commonly used for pathogenesis s...Due to their inability to generate a complete immune response, mice knockout for type I interferon （IFN） receptors （Ifnar-/-） are more susceptible to viral infections, and are thus commonly used for pathogenesis studies. This mouse model has been used to study many diseases caused by highly pathogenic viruses from many families, including the Flaviviridae, Filoviridae, Arenaviridae, Bunyaviridae, Henipaviridae, and Togaviridae. In this review, we summarize the findings from these animal studies, and discuss the pros and cons of using this model versus other known methods for studying pathogenesis in animals.展开更多
基金supported by the Key project of the Chinese Academy of Sciences(KJZD-SW-L11 to Z.-L.S.)the Guangzhou Laboratory(SRPG22-001 to Z.-L.S.)+3 种基金the Advanced Customer Cultivation Project of Wuhan National Biosafety Laboratory,Chinese Academy of Sciences(2021ACCP-MS02)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0490000 to X.-L.Y.)the Young Topnotch Talent Cultivation Program of Hubei Province(X.-L.Y.)the Youth Innovation Promotion Association of the Chinese Academy of Science(X.-L.Y.).
文摘Ebola virus(EBOV)and Marburg virus(MARV),members of the Filoviridae family,are highly pathogenic and can cause hemorrhagic fevers,significantly impacting human society.Bats are considered reservoirs of these viruses because related filoviruses have been discovered in bats.However,due to the requirement for maximum containment laboratories when studying infectious viruses,the characterization of bat filoviruses often relies on pseudoviruses and minigenome systems.In this study,we used RACE technology to sequence the 30-leader and 50-trailer of Mengla virus(MLAV)and constructed a minigenome.Similar to MARV,the transcription activities of the MLAV minigenome are independent of VP30.We further assessed the effects of polymorphisms at the 50 end on MLAV minigenome activity and identified certain mutations that decrease minigenome reporter efficiency,probably due to alterations in the RNA secondary structure.The reporter activity upon recombination of the 30-leaders and 50-trailers of MLAV,MARV,and EBOV with those of the homologous or heterologous minigenomes was compared and it was found that the polymerase complex and leader and trailer sequences exhibit intrinsic specificities.Additionally,we investigated whether the polymerase complex proteins from EBOV and MARV support MLAV minigenome RNA synthesis and found that the homologous system is more efficient than the heterologous system.Remdesivir efficiently inhibited MLAV as well as EBOV replication.In summary,this study provides new information on bat filoviruses and the minigenome will be a useful tool for high-throughput antiviral drug screening.
文摘Ebola virus(EBOV) and Marburg virus(MARV),belonging to the Filoviridae family,emerged four decades ago and caused severe viral hemorrhagic fever in human and other primates.As high as 50-90% mortality,filoviruses can cause significant threats to public health.However,so far no specific and efficient vaccine has been available,nor have other treatment methods proved to be effective.It is of great importance to detect these pathogens specific,rapidly and sensitively in order to control future filovirus outbreaks.Here,recent progresses in the development of detection and diagnosis methods for EBOV and MARV are summarized.
基金supported by the Public Health Agency of Canada(PHAC)partially supported by the NIH and CIHR grants to X.G.Qiu(U19 AI109762-1 and CIHR-IER-143487,respectively)+1 种基金the National Natural Science Foundation of China International Cooperation and Exchange Program(8161101193)National Science and Technology Major Project(2016ZX10004222)to G.Wong
文摘The family Filoviridae, which includes the genera Marburgvirus and Ebolavirus, contains some of the most pathogenic viruses in humans and non-human primates （NHPs）, causing severe hemorrhagic fevers with high fatality rates. Small animal models against filoviruses using mice, guinea pigs, hamsters, and ferrets have been developed with the goal of screening candidate vaccines and antivirals, before testing in the gold standard NHP models. In this review, we summarize the different animal models used to understand filovirus pathogenesis, and discuss the advantages and disadvantages of each model with respect to filovirus disease research.
基金funded by the Chemical-Biological Medical System-Joint Vaccine Acquisition Program (CBMS-JVAP) as well as the Defense Threat Reduction Agency (DTRA) (CBM.VAXV.03.11.RD.009 and A151 A.41)
文摘Filoviruses are hemorrhagic fever viruses endemic to parts of Africa and the Philippines. Infection carries with it a mortality rate of up to 90% and currently there are no effective vaccines or therapeutics available to combat infection. However, the filovirus virus-like particles (VLP), which are currently under development, have been shown to be a promising vaccine candidate. They provide protection from infection in the mouse, guinea pig, and nonhuman primate models of infection, eliciting high anti-glycoprotein antibody titers and T cell responses to viral proteins. In this review, we will highlight the development of the filovirus VLP and describe the current understanding of VLP immunogenicity and correlates of protection.
基金supported by grants from the National Natural Science Foundation of China (81202568, 81473256, and 81273561)the National Science and Technology Major Project (2015ZX09102-023-004)+1 种基金the CAMS Innovation Fund for Medical Sciences (2016-I2M-1–014)the Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study (BZ0150)
文摘Filoviruses cause severe and fatal viral hemorrhagic fever in humans. Filovirus research has been extensive since the 2014 Ebola outbreak. Due to their high pathogenicity and mortality, live filoviruses require Biosafety Level-4(BSL-4) facilities, which have restricted the development of anti-filovirus vaccines and drugs.An HIV-based pseudovirus cell infection assay is widely used for viral entry studies in BSL-2 conditions. Here,we successfully constructed nine in vitro pseudo-filovirus models covering all filovirus genera and three in vivo pseudo-filovirus-infection mouse models using Ebola virus, Marburg virus, and Lloviu virus as representative viruses. The pseudo-filovirus-infected mice showed visualizing bioluminescence in a dose-dependent manner. A bioluminescence peak in mice was reached on day 5 post-infection for Ebola virus and Marburg virus and on day4 post-infection for Lloviu virus. Two known filovirus entry inhibitors, clomiphene and toremiphene, were used to validate the model. Collectively, our study shows that all genera of filoviruses can be well-pseudotyped and are infectious in vitro. The pseudo-filovirus-infection mouse models can be used for in vivo activity evaluation of anti-filovirus drugs. This sequential in vitro and in vivo evaluation system of filovirus entry inhibitors provides a secure and efficient platform for screening and assessing anti-filovirus agents in BSL-2 facilities.
基金supported by the National Natural Science Foundation of China (Nos. 81673307 and 81321004)CAMS Innovation Fund for Medical Sciences (2016–I2M–3–009)
文摘Twenty-six novel tricyclic sophoridinic and matrinic derivatives containing a common chlorinated benzene fragment were designed, synthesized and evaluated for their anti-ebolavirus(EBOV)activities. Structure–activity relationship analysis indicated:(i) 12 N-dichlorobenzyl motif was beneficial for the activity;(ii) the chiral configuration at C5 atom might not affect the activity much. Among the target compounds, compound 7d exhibited the most potent potency against EBOV with an IC_(50) value of 5.29 μmol/L and an SI value of over 37.8. Further in vivo anti-EBOV assay of 7d identified its high effectiveness, and in vivo anti-MARV assay of 7d suggested its inspiring broad-spectrum anti-filovirus activity. The results provided powerful information on further strategic optimization and development of this kind of compounds against filoviruses.
基金supported by the Public Health Agency of Canada。
文摘The development of monoclonal antibodies to treat disease caused by filoviruses,particularly Ebola virus,has risen steeply in recent years thanks to several key studies demonstrating their remarkable therapeutic potential.The increased drive to develop new and better monoclonal antibodies has necessarily seen an increase in animal model efficacy testing,which is critical to the pre-clinical development of any novel countermeasure.Primary and secondary efficacy testing against filoviruses typically makes use of one or more rodent models(mice,guinea pigs,and occasionally hamsters)or the more recently described ferret model,although the exact choice of model depends on the specific filovirus being evaluated.Indeed,no single small animal model exists for all filoviruses,and the use of any given model must consider the nature of that model as well as the nature of the therapeutic and the experimental objectives.Confirmatory evaluation,on the other hand,is performed in nonhuman primates(rhesus or cynomolgus macaques)regardless of the filovirus.In light of the number of different animal models that are currently used in monoclonal antibody efficacy testing,we sought to better understand how these efficacy tests are being performed by numerous different laboratories around the world.To this end,we review the animal models that are being used for antibody efficacy testing against filoviruses,and we highlight the challenge doses and routes of infection that are used.We also describe the various antibody treatment regimens,including antibody dose,route,and schedule of administration,that are used in these model systems.We do not identify any single best model or treatment regimen,and we do not advocate for field-wide protocol standardization.Instead,we hope to provide a comprehensive resource that will facilitate and enhance the continued pre-clinical development of novel monoclonal antibody therapeutics.
基金supported by the National Natural Science Foundation of China International Cooperation and Exchange Program(8161101193)the National Science and Technology Major Project(2016ZX10004222)to G.Wong
文摘Due to their inability to generate a complete immune response, mice knockout for type I interferon （IFN） receptors （Ifnar-/-） are more susceptible to viral infections, and are thus commonly used for pathogenesis studies. This mouse model has been used to study many diseases caused by highly pathogenic viruses from many families, including the Flaviviridae, Filoviridae, Arenaviridae, Bunyaviridae, Henipaviridae, and Togaviridae. In this review, we summarize the findings from these animal studies, and discuss the pros and cons of using this model versus other known methods for studying pathogenesis in animals.
