Dear Editor,Viruses of the genus Orthoebolavirus cause sporadic outbreaks of severe haemorrhagic fever,with case fatality rates ranging from 25%to 90%(Mahanty and Bray,2004).Six species of the virus(Orthoebolavirus za...Dear Editor,Viruses of the genus Orthoebolavirus cause sporadic outbreaks of severe haemorrhagic fever,with case fatality rates ranging from 25%to 90%(Mahanty and Bray,2004).Six species of the virus(Orthoebolavirus zairense,sudanense,bundibugyoense,taiense,restonense,and bombaliense)have so far been identified(Biedenkopf et al.,2023).Among these,Orthoebolavirus zairense,commonly known as Ebola virus(EBOV),stands out as the most virulent.Given its high contagiousness and lethality,EBOV must be manipulated under biosafety level 4(BSL-4)conditions,as stipulated by the the People's Republic of China's list of human pathogenic microorganisms(National Health Commission of the People’s Republic of China,2023).Prior to being removed from a BSL-4 laboratory,it is imperative that infectious EBOV undergoes complete inactivation.Here we systematically evaluate viral thermostability under BSL-4 containment conditions,demonstrating EBOV's marked thermotolerance.展开更多
The Ebola virus(EBOV)is a member of the Orthoebolavirus genus,Filoviridae family,which causes severe hemorrhagic diseases in humans and non-human primates(NHPs),with a case fatality rate of up to 90%.The development o...The Ebola virus(EBOV)is a member of the Orthoebolavirus genus,Filoviridae family,which causes severe hemorrhagic diseases in humans and non-human primates(NHPs),with a case fatality rate of up to 90%.The development of countermeasures against EBOV has been hindered by the lack of ideal animal models,as EBOV requires handling in biosafety level(BSL)-4 facilities.Therefore,accessible and convenient animal models are urgently needed to promote prophylactic and therapeutic approaches against EBOV.In this study,a recombinant vesicular stomatitis virus expressing Ebola virus glycoprotein(VSV-EBOV/GP)was constructed and applied as a surrogate virus,establishing a lethal infection in hamsters.Following infection with VSV-EBOV/GP,3-week-old female Syrian hamsters exhibited disease signs such as weight loss,multi-organ failure,severe uveitis,high viral loads,and developed severe systemic diseases similar to those observed in human EBOV patients.All animals succumbed at 2–3 days post-infection(dpi).Histopathological changes indicated that VSV-EBOV/GP targeted liver cells,suggesting that the tissue tropism of VSV-EBOV/GP was comparable to wild-type EBOV(WT EBOV).Notably,the pathogenicity of the VSV-EBOV/GP was found to be species-specific,age-related,gender-associated,and challenge route-dependent.Subsequently,equine anti-EBOV immunoglobulins and a subunit vaccine were validated using this model.Overall,this surrogate model represents a safe,effective,and economical tool for rapid preclinical evaluation of medical countermeasures against EBOV under BSL-2 conditions,which would accelerate technological advances and breakthroughs in confronting Ebola virus disease.展开更多
埃博拉病毒(Ebola virus,EBOV)宿主广泛,其遗传进化关系复杂,影响埃博拉病毒密码子偏爱性的因素众多。为了明确人埃博拉病毒密码子使用的偏爱性,揭示影响其偏爱性的影响因素和不同宿主来源的埃博拉病毒间的遗传进化关系。本研究通过计...埃博拉病毒(Ebola virus,EBOV)宿主广泛,其遗传进化关系复杂,影响埃博拉病毒密码子偏爱性的因素众多。为了明确人埃博拉病毒密码子使用的偏爱性,揭示影响其偏爱性的影响因素和不同宿主来源的埃博拉病毒间的遗传进化关系。本研究通过计算有效密码子数(Effective number of codons,ENC),同义密码子相对使用频率(Relative synonymous codon usage,RSCU)和其他指标,对人埃博拉病毒的密码子使用模式进行综合分析。结果显示,人埃博拉病毒各蛋白的ENC均值分布于55.66~55.77,RSCU>1的密码子中77%以上都是以A/U结尾。中性绘图分析和PR2绘图分析等相关分析表明,自然选择是影响密码子使用模式的主要因素,突变压力的影响相对较小。聚类分析结果表明,猪和人来源的埃博拉病毒亲缘关系最近,提示猪来源的埃博拉病毒感染人的风险最大。新发现的bombali型埃博拉病毒与人的亲缘关系距离较远,在大多数蛋白中均单独聚类。本研究结果对深入了解人埃博拉病毒的遗传进化关系,进而研究埃博拉疫苗和制备抗体具有重大意义。展开更多
The recent Ebola outbreak in Western Africa was the most devastating outbreak witnessed in recent times,There have been remarkable local and international efforts to control the crisis,Ebola Virus Disease is the focus...The recent Ebola outbreak in Western Africa was the most devastating outbreak witnessed in recent times,There have been remarkable local and international efforts to control the crisis,Ebola Virus Disease is the focus of immense research activity,The progression of events in the region has been evolving swiftly and it is of paramount importance to the medical community to be acquainted with the situation,Over 28000 people were inflicted with the condition,over 11000 have died,Novel data has emerged regarding modes of transmission,providing rationale for recent flare-ups,Similarly,studies on survivors are elucidating the later stages of the disease recovery process,Novel techniques for diagnosis are also discussed,Finally,the current research regarding treatment and vaccine development is reviewed,particularly the implementation of r VSV-ZEBOV vaccination programs.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
This study aimed to investigate the serological characteristics of Ebola virus(EBOV) infection during the late phase of the Ebola outbreak in Sierra Leone. In total, 877 blood samples from 694 suspected Ebola virus di...This study aimed to investigate the serological characteristics of Ebola virus(EBOV) infection during the late phase of the Ebola outbreak in Sierra Leone. In total, 877 blood samples from 694 suspected Ebola virus disease(EVD) cases assessed from March to December 2015, were analyzed via real-time reverse transcription polymerase chain reaction(RT-PCR) for viral RNA and enzyme-linked immunosorbent assay(ELISA) and Luminex to detect antibodies against EBOV. Viral load and EBOV-specific IgM/IgG titers displayed a declining trend during March to December 2015. Viral RNA load decreased rapidly at earlier stages after disease onset, while EBOV-specific IgM and IgG still persisted in 58.1%(18/31) and 93.5%(29/31) of the confirmed EVD patients and in 3.8%(25/663) and 17.8%(118/663) of the RNA-negative suspected patients in the later phase, respectively. Dynamic analysis of longitudinally collected samples from eight EVD patients revealed typically reversed trends of declining viral load and increasing IgM and/or IgG titers in response to the EBOV infection.The present results indicate that certain populations of Sierra Leone developed immunity to an EBOV infection in the late phase of the outbreak, providing novel insights into the risk assessment of EBOV infections among human populations.展开更多
As one of the deadliest viruses,Ebola virus(EBOV)causes lethal hemorrhagic fevers in humans and nonhuman primates.The suppression of innate immunity leads to robust systemic virus replication of EBOV,leading to enhanc...As one of the deadliest viruses,Ebola virus(EBOV)causes lethal hemorrhagic fevers in humans and nonhuman primates.The suppression of innate immunity leads to robust systemic virus replication of EBOV,leading to enhanced transmission.However,the mechanism of EBOV-host interaction is not fully understood.Here,we identified multiple dysregulated genes in early stage of EBOV infection through transcriptomic analysis,which are highly clustered to Jak-STAT signaling.EBOV VP35 and VP30 were found to inhibit type I interferon(IFN)signaling.Moreover,exogenous expression of VP35 blocks the phosphorylation of endogenous STAT1,and suppresses nuclear translocation of STAT1.Using serial truncated mutations of VP35,N-terminal 1–220amino acid residues of VP35 were identified to be essential for blocking on type I IFN signaling.Remarkably,VP35 of EBOV suppresses type I IFN signaling more efficiently than those of Bundibugyo virus(BDBV)and Marburg virus(MARV),resulting in stable replication to facilitate the pathogenesis.Altogether,this study enriches understanding on EBOV evasion of innate immune response,and provides insights into the interplay between filoviruses and host.展开更多
Ebola virus(EBOV) belongs to the Filoviridae family and causes severe illnesses such as hemorrhagic fever with a high mortality rate up to 90%. Now two antibody drugs termed Inmazeb and Ebanga have been approved for t...Ebola virus(EBOV) belongs to the Filoviridae family and causes severe illnesses such as hemorrhagic fever with a high mortality rate up to 90%. Now two antibody drugs termed Inmazeb and Ebanga have been approved for treating EBOV infection. However, clinical studies have demonstrated that the mortality rate of the patients who received these two antibody drugs remains above 30%. Therefore, novel therapeutics with better efficacy is still desired. The isolated human IgG1 constant domain 2(CH2 domain) has been proposed as a scaffold for the development of C-based single domain antibodies(C-sd Abs) as therapeutic candidates against viral infections and other diseases. Here, we screened and identified a novel C-sd Ab termed M24 that targets EBOV glycoprotein(GP) from a C-sd Ab phage display library. M24 neutralizes the pseudotype EBOV with IC;of 0.8 nmol/L(12 ng/mL) and has modest neutralizing activity against authentic EBOV.Epitope determination, including molecular docking and site mutation analysis, discloses that M24 binds to the internal fusion loop(IFL) within GP2, a transmembrane subunit of GP. Interestingly, we found that the binding of M24 to GP at pH5.5 has dramatically decreased compared to the binding at pH 7.5, which may lead to weak efficacy in the neutralization of authentic EBOV. Since no sd Ab against EBOV infection has been reported to date, our results not only give a proof of concept that sd Abs could be utilized for the development of potential therapeutic candidates against EBOV infection, but also provide useful information for the discovery and improvement of anti-EBOV agents.展开更多
基金supported by the Youth Innovation Promotion Association of CAS(2023350 to Xiaoxiao Gao).
文摘Dear Editor,Viruses of the genus Orthoebolavirus cause sporadic outbreaks of severe haemorrhagic fever,with case fatality rates ranging from 25%to 90%(Mahanty and Bray,2004).Six species of the virus(Orthoebolavirus zairense,sudanense,bundibugyoense,taiense,restonense,and bombaliense)have so far been identified(Biedenkopf et al.,2023).Among these,Orthoebolavirus zairense,commonly known as Ebola virus(EBOV),stands out as the most virulent.Given its high contagiousness and lethality,EBOV must be manipulated under biosafety level 4(BSL-4)conditions,as stipulated by the the People's Republic of China's list of human pathogenic microorganisms(National Health Commission of the People’s Republic of China,2023).Prior to being removed from a BSL-4 laboratory,it is imperative that infectious EBOV undergoes complete inactivation.Here we systematically evaluate viral thermostability under BSL-4 containment conditions,demonstrating EBOV's marked thermotolerance.
基金supported by National Key R&D Program of China(grant number 2023YFC2605500)Jilin Province Youth Talent Support Project(grant number QT202208)+1 种基金the Ministry of Science and Technology of the People's Republic of China(grant number 2022YFC0867900)Nation Key Research and Development Program of China,New technology of rapid of pathogens in laboratory animals(grant number 2021YFF07033600).
文摘The Ebola virus(EBOV)is a member of the Orthoebolavirus genus,Filoviridae family,which causes severe hemorrhagic diseases in humans and non-human primates(NHPs),with a case fatality rate of up to 90%.The development of countermeasures against EBOV has been hindered by the lack of ideal animal models,as EBOV requires handling in biosafety level(BSL)-4 facilities.Therefore,accessible and convenient animal models are urgently needed to promote prophylactic and therapeutic approaches against EBOV.In this study,a recombinant vesicular stomatitis virus expressing Ebola virus glycoprotein(VSV-EBOV/GP)was constructed and applied as a surrogate virus,establishing a lethal infection in hamsters.Following infection with VSV-EBOV/GP,3-week-old female Syrian hamsters exhibited disease signs such as weight loss,multi-organ failure,severe uveitis,high viral loads,and developed severe systemic diseases similar to those observed in human EBOV patients.All animals succumbed at 2–3 days post-infection(dpi).Histopathological changes indicated that VSV-EBOV/GP targeted liver cells,suggesting that the tissue tropism of VSV-EBOV/GP was comparable to wild-type EBOV(WT EBOV).Notably,the pathogenicity of the VSV-EBOV/GP was found to be species-specific,age-related,gender-associated,and challenge route-dependent.Subsequently,equine anti-EBOV immunoglobulins and a subunit vaccine were validated using this model.Overall,this surrogate model represents a safe,effective,and economical tool for rapid preclinical evaluation of medical countermeasures against EBOV under BSL-2 conditions,which would accelerate technological advances and breakthroughs in confronting Ebola virus disease.
文摘埃博拉病毒(Ebola virus,EBOV)宿主广泛,其遗传进化关系复杂,影响埃博拉病毒密码子偏爱性的因素众多。为了明确人埃博拉病毒密码子使用的偏爱性,揭示影响其偏爱性的影响因素和不同宿主来源的埃博拉病毒间的遗传进化关系。本研究通过计算有效密码子数(Effective number of codons,ENC),同义密码子相对使用频率(Relative synonymous codon usage,RSCU)和其他指标,对人埃博拉病毒的密码子使用模式进行综合分析。结果显示,人埃博拉病毒各蛋白的ENC均值分布于55.66~55.77,RSCU>1的密码子中77%以上都是以A/U结尾。中性绘图分析和PR2绘图分析等相关分析表明,自然选择是影响密码子使用模式的主要因素,突变压力的影响相对较小。聚类分析结果表明,猪和人来源的埃博拉病毒亲缘关系最近,提示猪来源的埃博拉病毒感染人的风险最大。新发现的bombali型埃博拉病毒与人的亲缘关系距离较远,在大多数蛋白中均单独聚类。本研究结果对深入了解人埃博拉病毒的遗传进化关系,进而研究埃博拉疫苗和制备抗体具有重大意义。
文摘The recent Ebola outbreak in Western Africa was the most devastating outbreak witnessed in recent times,There have been remarkable local and international efforts to control the crisis,Ebola Virus Disease is the focus of immense research activity,The progression of events in the region has been evolving swiftly and it is of paramount importance to the medical community to be acquainted with the situation,Over 28000 people were inflicted with the condition,over 11000 have died,Novel data has emerged regarding modes of transmission,providing rationale for recent flare-ups,Similarly,studies on survivors are elucidating the later stages of the disease recovery process,Novel techniques for diagnosis are also discussed,Finally,the current research regarding treatment and vaccine development is reviewed,particularly the implementation of r VSV-ZEBOV vaccination programs.
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 National Mega project for Infectious Disease,Ministry of Science and technology(Grant Nos.2016ZX10004222-002,2016ZX10004222-003)National Natural Science Foundation of China(Grant Nos.81373141 and 81401312)National key project of Ebola research,National Natural Science Foundation of China(NSFC,Grant No.81590763)
文摘This study aimed to investigate the serological characteristics of Ebola virus(EBOV) infection during the late phase of the Ebola outbreak in Sierra Leone. In total, 877 blood samples from 694 suspected Ebola virus disease(EVD) cases assessed from March to December 2015, were analyzed via real-time reverse transcription polymerase chain reaction(RT-PCR) for viral RNA and enzyme-linked immunosorbent assay(ELISA) and Luminex to detect antibodies against EBOV. Viral load and EBOV-specific IgM/IgG titers displayed a declining trend during March to December 2015. Viral RNA load decreased rapidly at earlier stages after disease onset, while EBOV-specific IgM and IgG still persisted in 58.1%(18/31) and 93.5%(29/31) of the confirmed EVD patients and in 3.8%(25/663) and 17.8%(118/663) of the RNA-negative suspected patients in the later phase, respectively. Dynamic analysis of longitudinally collected samples from eight EVD patients revealed typically reversed trends of declining viral load and increasing IgM and/or IgG titers in response to the EBOV infection.The present results indicate that certain populations of Sierra Leone developed immunity to an EBOV infection in the late phase of the outbreak, providing novel insights into the risk assessment of EBOV infections among human populations.
基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0490000)the National Natural Science Foundation of China(82202521).
文摘As one of the deadliest viruses,Ebola virus(EBOV)causes lethal hemorrhagic fevers in humans and nonhuman primates.The suppression of innate immunity leads to robust systemic virus replication of EBOV,leading to enhanced transmission.However,the mechanism of EBOV-host interaction is not fully understood.Here,we identified multiple dysregulated genes in early stage of EBOV infection through transcriptomic analysis,which are highly clustered to Jak-STAT signaling.EBOV VP35 and VP30 were found to inhibit type I interferon(IFN)signaling.Moreover,exogenous expression of VP35 blocks the phosphorylation of endogenous STAT1,and suppresses nuclear translocation of STAT1.Using serial truncated mutations of VP35,N-terminal 1–220amino acid residues of VP35 were identified to be essential for blocking on type I IFN signaling.Remarkably,VP35 of EBOV suppresses type I IFN signaling more efficiently than those of Bundibugyo virus(BDBV)and Marburg virus(MARV),resulting in stable replication to facilitate the pathogenesis.Altogether,this study enriches understanding on EBOV evasion of innate immune response,and provides insights into the interplay between filoviruses and host.
基金This work was jointly supported by the Advanced Customer Cultivation Project of Wuhan National Biosafety Laboratory,Chinese Academy of Sciences(2021ACCP-MS01,2019ACCP-ZD03)the Natural Science Foundation of Hubei Province of China(2019CFA076)the National Natural Science Foundation of China(31870926)。
文摘Ebola virus(EBOV) belongs to the Filoviridae family and causes severe illnesses such as hemorrhagic fever with a high mortality rate up to 90%. Now two antibody drugs termed Inmazeb and Ebanga have been approved for treating EBOV infection. However, clinical studies have demonstrated that the mortality rate of the patients who received these two antibody drugs remains above 30%. Therefore, novel therapeutics with better efficacy is still desired. The isolated human IgG1 constant domain 2(CH2 domain) has been proposed as a scaffold for the development of C-based single domain antibodies(C-sd Abs) as therapeutic candidates against viral infections and other diseases. Here, we screened and identified a novel C-sd Ab termed M24 that targets EBOV glycoprotein(GP) from a C-sd Ab phage display library. M24 neutralizes the pseudotype EBOV with IC;of 0.8 nmol/L(12 ng/mL) and has modest neutralizing activity against authentic EBOV.Epitope determination, including molecular docking and site mutation analysis, discloses that M24 binds to the internal fusion loop(IFL) within GP2, a transmembrane subunit of GP. Interestingly, we found that the binding of M24 to GP at pH5.5 has dramatically decreased compared to the binding at pH 7.5, which may lead to weak efficacy in the neutralization of authentic EBOV. Since no sd Ab against EBOV infection has been reported to date, our results not only give a proof of concept that sd Abs could be utilized for the development of potential therapeutic candidates against EBOV infection, but also provide useful information for the discovery and improvement of anti-EBOV agents.
