Cyanophages are double-stranded DNA viruses that infect cyanobacteria,and they can be found in both freshwater and marine environments.They have a complex pattern of host ranges and play important roles in controlling...Cyanophages are double-stranded DNA viruses that infect cyanobacteria,and they can be found in both freshwater and marine environments.They have a complex pattern of host ranges and play important roles in controlling cyanobacteria population.Unlike marine cyanophages,for which there have been a number of recent investigations,very little attention has been paid to freshwater cyanophages.This review summarizes the taxonomy and morphology,host range,distribution,seasonal dynamics,and complete genomes of freshwater cyanophages,as well as diagnostic markers that can be used to identify them.展开更多
Cyanophages are ubiquitous and essential components of the aquatic environment and play an important role in the termination of algal blooms.As such,they have attracted widespread interest.PP was the first isolated cy...Cyanophages are ubiquitous and essential components of the aquatic environment and play an important role in the termination of algal blooms.As such,they have attracted widespread interest.PP was the first isolated cyanophage in China,which infects Plectonema boryanum and Phormidium foveolarum.In this study,this cyanophage was purified three times by a double-agar overlay plaque assay and characterized.Its genome was extracted,totally sequenced and analyzed.Electron microscopy revealed a particle with an icosahedral head connected to a short stubby tail.Bioassays showed that PP was quite virulent.The genome of PP is a 42,480 base pair(bp),linear,double-stranded DNA molecule with 222 bp terminal repeats.It has high similarity with the known Pf-WMP3 sequence.It contains 41 open reading frames(ORFs),17 of which were annotated.Intriguingly,the genome can be divided into two completely different parts,which differ both in orientation and function.展开更多
Dear Editor,Nucleotide and protein sequences of isolates collectedfrom infected populations can be useful for determiningthe threats,such as host adaptation,which are associatedwith the emergence of new lineages.March...Dear Editor,Nucleotide and protein sequences of isolates collectedfrom infected populations can be useful for determiningthe threats,such as host adaptation,which are associatedwith the emergence of new lineages.March 2013 saw thefirst reports of a new H7N9 lineage in Shanghai,Chinathat saw a gradual increase in the number of cases;but,by 17th May 2013,four Chinese provinces had展开更多
Cyanobacteria and eukaryotic algae are abundant in freshwater and marine environments,and are fundamentally important in global biogeochemical cycles and for primary productivity.Under certain conditions,such as an ex...Cyanobacteria and eukaryotic algae are abundant in freshwater and marine environments,and are fundamentally important in global biogeochemical cycles and for primary productivity.Under certain conditions,such as an excess of nutrients due to human activities through fertilizers or sewage,展开更多
P74 is a per os infectivity factor of baculovirus.Here,we report the production of three monoclonal antibodies (mAbs),denoted as 20D9,20F9 and 21E1,raised against P74 of Helicoverpa armigera nucleopolyhedrovirus (Hear...P74 is a per os infectivity factor of baculovirus.Here,we report the production of three monoclonal antibodies (mAbs),denoted as 20D9,20F9 and 21E1,raised against P74 of Helicoverpa armigera nucleopolyhedrovirus (HearNPV),and the identification of their recognition epitopes.The full-length P74,without the transmembrane domains at the C-terminus,was first divided into three segments (N,M and C,respectively),based on the proposed cleavage model for the protein,which were then expressed individually.Western blot analyses revealed specific cross-reactions with the N fragment,for both 20D9 and 21E1.Extensive truncation,followed by prokaryotic expression,of the P74 N fragment was then performed in order to screen for linear epitopes of P74.The recognition regions of 20D9 and 21E1 were revealed to be localized at R144-T153 and T199-C219,respectively.In addition,immunofluorescence microscopy indicated that 20D9 and 20F9 could recognize native P74 in HearNPV-infected cells.These findings will facilitate further investigations of the proteolytic processing of HearNPV P74,and of its involvement in virus-host interactions.展开更多
Severe fever with thrombocytopenia syndrome(SFTS)caused by the SFTS virus(SFTSV)is an emerging disease in East Asia with a fatality rate of up to 30%.However,the viral-host interaction of SFTSV remains largely unknown...Severe fever with thrombocytopenia syndrome(SFTS)caused by the SFTS virus(SFTSV)is an emerging disease in East Asia with a fatality rate of up to 30%.However,the viral-host interaction of SFTSV remains largely unknown.The heat-shock protein 90(Hsp90)family consists of highly conserved chaperones that fold and remodel proteins and has a broad impact on the infection of many viruses.Here,we showed that Hsp90 is an important host factor involved in SFTSV infection.Hsp90 inhibitors significantly reduced SFTSV replication,viral protein expression,and the formation of inclusion bodies consisting of nonstructural proteins(NSs).Among viral proteins,NSs appeared to be the most reduced when Hsp90 inhibitors were used,and further analysis showed that their translation was affected.Co-immunoprecipitation of NSs with four isomers of Hsp90 showed that Hsp90βspecifically interacted with them.Knockdown of Hsp90βexpression also inhibited replication of SFTSV.These results suggest that Hsp90βplays a critical role during SFTSV infection and could be a potential target for the development of drugs against SFTS.展开更多
Hubei Province is a major epidemic area of severe fever with thrombocytopenia syndrome bunyavirus(SFTSV) in China. However, to date, a few SFTSV strains have been isolated from Hubei Province, preventing effective stu...Hubei Province is a major epidemic area of severe fever with thrombocytopenia syndrome bunyavirus(SFTSV) in China. However, to date, a few SFTSV strains have been isolated from Hubei Province, preventing effective studies of epidemic outbreaks. Here, we report three confirmed patients(2015–2016) with typical symptoms of severe fever with thrombocytopenia syndrome disease(SFTS) who were farmers resident in different regions in Hubei Province. Three new SFTSV strains were isolated from the serum samples of each patient. Characterization of viral growth properties showed that there were no significant differences in virus production. All strains were completely sequenced, and phylogenetic analysis showed that unlike the other strains from Hubei province, which belonged to the SFTSV C3 genotype, one of the three strains belonged to the SFTSV C2 genotype. These results suggested that multiple SFTSV genotypes have been circulating in Hubei Province, providing insights into SFTSV evolution and improving our understanding of SFTSV prevalence in Hubei Province.展开更多
Neutralizing monoclonal antibodies(mAb)are a major therapeutic strategy for the treatment of severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection.The continuous emergence of new SARS-CoV-2 variants wor...Neutralizing monoclonal antibodies(mAb)are a major therapeutic strategy for the treatment of severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection.The continuous emergence of new SARS-CoV-2 variants worldwide has increased the urgency for the development of new mAbs.In this study,we immunized mice with the receptor-binding domain(RBD)of the SARS-CoV-2 prototypic strain(WIV04)and screened 35 RBDspecific mAbs using hybridoma technology.Results of the plaque reduction neutralization test showed that 25 of the mAbs neutralized authentic WIV04 strain infection.The 25 mAbs were divided into three categories based on the competitive enzyme-linked immunosorbent assay results.A representative mAb was selected from each category(RD4,RD10,and RD14)to determine the binding kinetics and median inhibitory concentration(IC_(50))of WIV04 and two variants of concern(VOC):B.1.351(Beta)and B.1.617.2(Delta).RD4 neutralized the B.1.617.2 variant with an IC50 of 2.67 ng/mL;however,it completely lost neutralizing activity against the B.1.351 variant.RD10 neutralized both variants with an IC50 exceeding 100 ng/mL;whereas RD14 neutralized two variants with a higher IC50(>1 mg/mL).Animal experiments were performed to evaluate the protective effects of RD4 and RD10 against various VOC infections.RD4 could protect Adv-hACE2 transduced mice from B.1.617.2 infection at an antibody concentration of 25 mg/kg,while RD10 could protect mice from B.1.351 infection at an antibody concentration of 75 mg/kg.These results highlight the potential for future modifications of the mAbs for practical use.展开更多
Herpes simplex virus type 1(HSV-1)causes lifelong infections worldwide,and currently there is no efficient cure or vaccine.HSV-1-derived tools,such as neuronal circuit tracers and oncolytic viruses,have been used exte...Herpes simplex virus type 1(HSV-1)causes lifelong infections worldwide,and currently there is no efficient cure or vaccine.HSV-1-derived tools,such as neuronal circuit tracers and oncolytic viruses,have been used exten-sively;however,further genetic engineering of HSV-1 is hindered by its complex genome structure.In the present study,we designed and constructed a synthetic platform for HSV-1 based on H129-G4.The complete genome was constructed from 10 fragments through 3 rounds of synthesis using transformation-associated recombination(TAR)in yeast,and was named H129-Syn-G2.The H129-Syn-G2 genome contained two copies of the gfp gene and was transfected into cells to rescue the virus.According to growth curve assay and electron microscopy results,the synthetic viruses exhibited more optimized growth properties and similar morphogenesis compared to the parental virus.This synthetic platform will facilitate further manipulation of the HSV-1 genome for the devel-opment of neuronal circuit tracers,oncolytic viruses,and vaccines.展开更多
Ticks are important vectors for the transmission of pathogens including viruses.The viruses carried by ticks also known as tick-borne viruses(TBVs),contain a large group of viruses with diverse genetic properties and ...Ticks are important vectors for the transmission of pathogens including viruses.The viruses carried by ticks also known as tick-borne viruses(TBVs),contain a large group of viruses with diverse genetic properties and are concluded in two orders,nine families,and at least 12 genera.Some members of the TBVs are notorious agents causing severe diseases with high mortality rates in humans and livestock,while some others may pose risks to public health that are still unclear to us.Herein,we review the current knowledge of TBVs with emphases on the history of virus isolation and identification,tick vectors,and potential pathogenicity to humans and animals,including assigned species as well as the recently discovered and unassigned species.All these will promote our understanding of the diversity of TBVs,and will facilitate the further investigation of TBVs in association with both ticks and vertebrate hosts.展开更多
Crimean-Congo hemorrhagic fever(CCHF)caused by the CCHF virus(CCHFV)is a tick-borne natural focal disease with a mortality rate of approximately 50%.CCHFV is widely prevalent in Africa,southern Asia,the Middle East,an...Crimean-Congo hemorrhagic fever(CCHF)caused by the CCHF virus(CCHFV)is a tick-borne natural focal disease with a mortality rate of approximately 50%.CCHFV is widely prevalent in Africa,southern Asia,the Middle East,and southeast Europe.CCHF outbreaks have been reported previously in Xinjiang province,China,especially in its southern region.Epidemiological surveys conducted on ticks and animals have revealed the presence of CCHFV strains in ticks,rodents,and infected individuals from cities and counties in southern Xinjiang.Phylogenetic analyses revealed that the Chinese CCHFV strains belong to one genotype,based on complete sequences of the S segments of its negative-stranded RNA genome.The present study reports two new CCHFV strains isolated from Hyalomma asiaticum asiaticum ticks collected from Fukang City and Wujiaqu City in the northern region of Xinjiang.Viral characteristics and their evolutionary relationships were analyzed through metagenomic and reverse-transcription PCR analyses;these analyses indicated that the genotype of both strains was different from that of other Chinese strains.Furthermore,previous reports of CCHFV in Xinjiang were reviewed and phylogenetic analyses were performed.CCHFV was found to prevail in Fukang City in Junggar Basin for more than 20 years,and that Fukang City and Wujiaqu City are considered natural reservoirs of different genotypes of CCHFV strains.Our findings facilitate the understanding of CCHFV distribution in Xinjiang province and provide insights into the evolutionary relationships among Chinese CCHFV strains.展开更多
Emerging infectious diseases are major threats to human health.Most severe viral disease outbreaks occur in developing regions where health conditions are poor.With increased international travel and business,the poss...Emerging infectious diseases are major threats to human health.Most severe viral disease outbreaks occur in developing regions where health conditions are poor.With increased international travel and business,the possibility of eventually transmitting infectious viruses between different countries is increasing.The most effective approach in preventing viral diseases is vaccination.However,vaccines are not currently available for numerous viral diseases.Viruslike particles(VLPs) are engineered vaccine candidates that have been studied for decades.VLPs are constructed by viral protein expression in various expression systems that promote the selfassembly of proteins into structures resembling virus particles.VLPs have antigenicity similar to that of the native virus,but are non-infectious as they lack key viral genetic material.VLP vaccines have attracted considerable research interest because they offer several advantages over traditional vaccines.Studies have shown that VLP vaccines can stimulate both humoral and cellular immune responses,which may offer effective antiviral protection.Here we review recent developments with VLP-based vaccines for several highly virulent emerging or re-emerging infectious diseases.The infectious agents discussed include RNA viruses from different virus families,such as the Arenaviridae,Bunyaviridae,Caliciviridae,Coronaviridae,Filoviridae,Flaviviridae,Orthomyxoviridae,Paramyxoviridae,and Togaviridae families.展开更多
The Crimean-Congo hemorrhagic fever virus(CCHFV),a member of the genus Orthonairovirus and family Nairoviridae,is transmitted by ticks and causes severe hemorrhagic disease in humans.To study the epidemiology of CCHFV...The Crimean-Congo hemorrhagic fever virus(CCHFV),a member of the genus Orthonairovirus and family Nairoviridae,is transmitted by ticks and causes severe hemorrhagic disease in humans.To study the epidemiology of CCHFV in different ecosystems in Xinjiang,China,a total of 58,932 ticks were collected from Tarim Basin,Junggar Basin,Tianshan Mountain,and Altai Mountain from 2014 to 2017.Hyalomma asiaticum asiaticum was the dominant tick species in Tarim and Junggar basins,whereas Dermacentor nuttalli and Hyalomma detritum were found in Tianshan Mountain and Altai Mountain,respectively.Reverse transcription-polymerase chain reaction of the CCHFV small(S)genome segment was used for the molecular detection.The CCHFV-positive percentage was 5.26%,6.85%,1.94%,and 5.56% in Tarim Basin,Junggar Basin,Tianshan Mountain,and Altai Mountain,respectively.Sequences of the S segment were used for phylogenetic analysis and the results showed that the newly identified CCHFV strains belonged to two clades.Our study confirms that H.asiaticum asiaticum is the major vector of CCHFV in desert habitats which is consistent with previous studies,and also suggests that H.detritum and D.nuttalli are emerging vectors for CCHFV in Xinjiang.Moreover,this study reports the presence of CCHFV in the mountain habitat of Xinjiang for the first time,suggesting that future surveillance of CCHFV should also include mountainous areas.展开更多
No ascovirus isolated from China has been sequenced so far. Therefore, in this study, we aimed to sequence the genome of Heliothis virescens ascovirus 3h(Hv AV-3h) using the 454 pyrosequencing technology. The genome w...No ascovirus isolated from China has been sequenced so far. Therefore, in this study, we aimed to sequence the genome of Heliothis virescens ascovirus 3h(Hv AV-3h) using the 454 pyrosequencing technology. The genome was found to be 190,519-bp long with a G+C content of 45.5%. We also found that it encodes 185 hypothetical open reading frames(ORFs) along with at least 50 amino acids, including 181 ORFs found in other ascoviruses and 4 unique ORFs. Gene-parity plots and phylogenetic analysis revealed a close relationship between Hv AV-3h and three other Hv AV-3a strains and a distant relationship with Spodoptera frugiperda ascovirus 1a(Sf AV-1a), Trichoplusia ni ascovirus 6a(Tn AV-6a), and Diadromus pulchellus ascovirus 4a(Dp AV-4a). Among the 185 potential genes encoded by the genome, 44 core genes were found in all the sequenced ascoviruses. In addition, 25 genes were found to be conserved in all ascoviruses except Dp AV-4a.In the Hv AV-3h genome, 24 baculovirus repeat ORFs(bros) were present, and the typical homologous repeat regions(hrs) were absent. This study supplies information important for understanding the conservation and functions of ascovirus genes as well as the variety of ascoviral genomes.展开更多
Crimean-Congo hemorrhagic fever virus(CCHFV) is a highly pathogenic tick-borne virus with a fatality rate of up to 50% in humans. CCHFV is widely distributed in countries around the world.Outbreaks of CCHFV infection ...Crimean-Congo hemorrhagic fever virus(CCHFV) is a highly pathogenic tick-borne virus with a fatality rate of up to 50% in humans. CCHFV is widely distributed in countries around the world.Outbreaks of CCHFV infection in humans have occurred in prior years in Xinjiang Province, China.Epidemiological surveys have detected CCHFV RNA in ticks and animals; however, few isolates were identified. In this study, we identified and isolated a new CCHFV strain from Hyalomma asiaticum asiaticum ticks collected from north of Tarim Basin in Xinjiang, China. A preliminary investigation of infection and antigens expression of CCHFV was performed in newborn mice. The target tissues for CCHFV replication in newborn mice were identified. The analysis of the phylogenetic relationships with other Chinese strains suggested that diverse genotypes of CCHFV have circulated in Xinjiang for years. These findings provide important insights into our understanding of CCHFV infection and evolution as well as disease prevention and control for local residents.展开更多
Baculoviruses are a family of arthropod-specific large DNA viruses that infect insect species belonging to the orders Lepidoptera,Hymenoptera and Diptera.In nature,occlusion-derived viruses(ODVs) initiate baculovirus ...Baculoviruses are a family of arthropod-specific large DNA viruses that infect insect species belonging to the orders Lepidoptera,Hymenoptera and Diptera.In nature,occlusion-derived viruses(ODVs) initiate baculovirus primary infection in the midgut epithelium of insect hosts,and this process is largely dependent on a number of ODV envelope proteins designated as per os infectivity factors(PIFs).Interestingly,PIF homologs are also present in other invertebrate large DNA viruses,which is indicative that per os infection is an ancient and phylogenetically conserved entry mechanism shared by these viruses.Here,we review the advances in the knowledge of the functions of individual PIFs and recent discoveries about the PIF complex,and discuss the evolutionary implications of PIF homologs in invertebrate DNA viruses.Furthermore,future research highlights on the per os infection mechanism are also prospected.展开更多
Recent outbreaks of Zika virus(ZIKV) infections in Oceania's islands and the Americas were characterized by high numbers of cases and the spread of the virus to new areas. To better understand the origin of ZIKV, ...Recent outbreaks of Zika virus(ZIKV) infections in Oceania's islands and the Americas were characterized by high numbers of cases and the spread of the virus to new areas. To better understand the origin of ZIKV, its epidemic history was reviewed. Although the available records and information are limited, two major genetic lineages of ZIKV were identified in previous studies.However, in this study, three lineages were identified based on a phylogenetic analysis of all virus sequences from Gen Bank, including those of the envelope protein(E) and non-structural protein 5(NS5) coding regions. The spatial and temporal distributions of the three identified ZIKV lineages and the recombination events and mechanisms underlying their divergence and evolution were further elaborated. The potential migration pathway of ZIKV was also characterized. Our findings revealed the central roles of two African countries, Senegal and Cote d'Ivoire, in ZIKV evolution and genotypic divergence. Furthermore, our results suggested that the outbreaks in Asia and the Pacific islands originated from Africa. The results provide insights into the geographic origins of ZIKV outbreaks and the spread of the virus, and also contribute to a better understanding of ZIKV evolution, which is important for the prevention and control of ZIKV infections.展开更多
文摘Cyanophages are double-stranded DNA viruses that infect cyanobacteria,and they can be found in both freshwater and marine environments.They have a complex pattern of host ranges and play important roles in controlling cyanobacteria population.Unlike marine cyanophages,for which there have been a number of recent investigations,very little attention has been paid to freshwater cyanophages.This review summarizes the taxonomy and morphology,host range,distribution,seasonal dynamics,and complete genomes of freshwater cyanophages,as well as diagnostic markers that can be used to identify them.
文摘Cyanophages are ubiquitous and essential components of the aquatic environment and play an important role in the termination of algal blooms.As such,they have attracted widespread interest.PP was the first isolated cyanophage in China,which infects Plectonema boryanum and Phormidium foveolarum.In this study,this cyanophage was purified three times by a double-agar overlay plaque assay and characterized.Its genome was extracted,totally sequenced and analyzed.Electron microscopy revealed a particle with an icosahedral head connected to a short stubby tail.Bioassays showed that PP was quite virulent.The genome of PP is a 42,480 base pair(bp),linear,double-stranded DNA molecule with 222 bp terminal repeats.It has high similarity with the known Pf-WMP3 sequence.It contains 41 open reading frames(ORFs),17 of which were annotated.Intriguingly,the genome can be divided into two completely different parts,which differ both in orientation and function.
文摘Dear Editor,Nucleotide and protein sequences of isolates collectedfrom infected populations can be useful for determiningthe threats,such as host adaptation,which are associatedwith the emergence of new lineages.March 2013 saw thefirst reports of a new H7N9 lineage in Shanghai,Chinathat saw a gradual increase in the number of cases;but,by 17th May 2013,four Chinese provinces had
文摘Cyanobacteria and eukaryotic algae are abundant in freshwater and marine environments,and are fundamentally important in global biogeochemical cycles and for primary productivity.Under certain conditions,such as an excess of nutrients due to human activities through fertilizers or sewage,
基金supported by the National Science Foundation of China(31130058 to Z.H.).Monoclonal Antibodies against HearNPV P74
文摘P74 is a per os infectivity factor of baculovirus.Here,we report the production of three monoclonal antibodies (mAbs),denoted as 20D9,20F9 and 21E1,raised against P74 of Helicoverpa armigera nucleopolyhedrovirus (HearNPV),and the identification of their recognition epitopes.The full-length P74,without the transmembrane domains at the C-terminus,was first divided into three segments (N,M and C,respectively),based on the proposed cleavage model for the protein,which were then expressed individually.Western blot analyses revealed specific cross-reactions with the N fragment,for both 20D9 and 21E1.Extensive truncation,followed by prokaryotic expression,of the P74 N fragment was then performed in order to screen for linear epitopes of P74.The recognition regions of 20D9 and 21E1 were revealed to be localized at R144-T153 and T199-C219,respectively.In addition,immunofluorescence microscopy indicated that 20D9 and 20F9 could recognize native P74 in HearNPV-infected cells.These findings will facilitate further investigations of the proteolytic processing of HearNPV P74,and of its involvement in virus-host interactions.
基金supported by grants from the National Natural Science Foundation of China(31900146)the key Biosafety Science and Technology Program of Hubei Jiangxia Laboratory(JXBS001)+1 种基金the Hubei Natural Science Foundation for Distinguished Young Scholars(2021CFA050)the Creative Research Group Program of Natural Science Foundation of Hubei Province(2022CFA021).
文摘Severe fever with thrombocytopenia syndrome(SFTS)caused by the SFTS virus(SFTSV)is an emerging disease in East Asia with a fatality rate of up to 30%.However,the viral-host interaction of SFTSV remains largely unknown.The heat-shock protein 90(Hsp90)family consists of highly conserved chaperones that fold and remodel proteins and has a broad impact on the infection of many viruses.Here,we showed that Hsp90 is an important host factor involved in SFTSV infection.Hsp90 inhibitors significantly reduced SFTSV replication,viral protein expression,and the formation of inclusion bodies consisting of nonstructural proteins(NSs).Among viral proteins,NSs appeared to be the most reduced when Hsp90 inhibitors were used,and further analysis showed that their translation was affected.Co-immunoprecipitation of NSs with four isomers of Hsp90 showed that Hsp90βspecifically interacted with them.Knockdown of Hsp90βexpression also inhibited replication of SFTSV.These results suggest that Hsp90βplays a critical role during SFTSV infection and could be a potential target for the development of drugs against SFTS.
基金supported by the Science and Technology Basic Work Program (2013FY113500)the National Key Research and Development Program (2016YFE 0113500) from the Ministry of Science and Technology of Chinathe European Union’s Horizon 2020 EVAg project (No 653316)
文摘Hubei Province is a major epidemic area of severe fever with thrombocytopenia syndrome bunyavirus(SFTSV) in China. However, to date, a few SFTSV strains have been isolated from Hubei Province, preventing effective studies of epidemic outbreaks. Here, we report three confirmed patients(2015–2016) with typical symptoms of severe fever with thrombocytopenia syndrome disease(SFTS) who were farmers resident in different regions in Hubei Province. Three new SFTSV strains were isolated from the serum samples of each patient. Characterization of viral growth properties showed that there were no significant differences in virus production. All strains were completely sequenced, and phylogenetic analysis showed that unlike the other strains from Hubei province, which belonged to the SFTSV C3 genotype, one of the three strains belonged to the SFTSV C2 genotype. These results suggested that multiple SFTSV genotypes have been circulating in Hubei Province, providing insights into SFTSV evolution and improving our understanding of SFTSV prevalence in Hubei Province.
基金supported by grants from the National Key R&D Program of China(2021YFC2301700)National Natural Science Foundation of China(82061138021)+1 种基金the Key Biosafety Science and Technology Program of Hubei Jiangxia Laboratory(JXBS001)Hubei Natural Science Foundation for Distinguished Young Scholars(2021CFA050).
文摘Neutralizing monoclonal antibodies(mAb)are a major therapeutic strategy for the treatment of severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection.The continuous emergence of new SARS-CoV-2 variants worldwide has increased the urgency for the development of new mAbs.In this study,we immunized mice with the receptor-binding domain(RBD)of the SARS-CoV-2 prototypic strain(WIV04)and screened 35 RBDspecific mAbs using hybridoma technology.Results of the plaque reduction neutralization test showed that 25 of the mAbs neutralized authentic WIV04 strain infection.The 25 mAbs were divided into three categories based on the competitive enzyme-linked immunosorbent assay results.A representative mAb was selected from each category(RD4,RD10,and RD14)to determine the binding kinetics and median inhibitory concentration(IC_(50))of WIV04 and two variants of concern(VOC):B.1.351(Beta)and B.1.617.2(Delta).RD4 neutralized the B.1.617.2 variant with an IC50 of 2.67 ng/mL;however,it completely lost neutralizing activity against the B.1.351 variant.RD10 neutralized both variants with an IC50 exceeding 100 ng/mL;whereas RD14 neutralized two variants with a higher IC50(>1 mg/mL).Animal experiments were performed to evaluate the protective effects of RD4 and RD10 against various VOC infections.RD4 could protect Adv-hACE2 transduced mice from B.1.617.2 infection at an antibody concentration of 25 mg/kg,while RD10 could protect mice from B.1.351 infection at an antibody concentration of 75 mg/kg.These results highlight the potential for future modifications of the mAbs for practical use.
基金Wuhan Institute of Virology for financial support for the research(grant no.EISA020201).
文摘Herpes simplex virus type 1(HSV-1)causes lifelong infections worldwide,and currently there is no efficient cure or vaccine.HSV-1-derived tools,such as neuronal circuit tracers and oncolytic viruses,have been used exten-sively;however,further genetic engineering of HSV-1 is hindered by its complex genome structure.In the present study,we designed and constructed a synthetic platform for HSV-1 based on H129-G4.The complete genome was constructed from 10 fragments through 3 rounds of synthesis using transformation-associated recombination(TAR)in yeast,and was named H129-Syn-G2.The H129-Syn-G2 genome contained two copies of the gfp gene and was transfected into cells to rescue the virus.According to growth curve assay and electron microscopy results,the synthetic viruses exhibited more optimized growth properties and similar morphogenesis compared to the parental virus.This synthetic platform will facilitate further manipulation of the HSV-1 genome for the devel-opment of neuronal circuit tracers,oncolytic viruses,and vaccines.
基金supported by Science and Technology Basic Work Program (2013FY113500) from the Ministry of Science and Technology of Chinathe European Union’s Horizon 2020 Research and Innovation Programme (No.653316)+1 种基金the Strategic Bio-resource Service Network Plan and Building the Biogenetic Resource Preserving Capacity Program from the Chinese Academy of Sciences (ZSSB-002)the Hubei Provincial program of scientific and technological condition platform establishment (2017BEC003)
文摘Ticks are important vectors for the transmission of pathogens including viruses.The viruses carried by ticks also known as tick-borne viruses(TBVs),contain a large group of viruses with diverse genetic properties and are concluded in two orders,nine families,and at least 12 genera.Some members of the TBVs are notorious agents causing severe diseases with high mortality rates in humans and livestock,while some others may pose risks to public health that are still unclear to us.Herein,we review the current knowledge of TBVs with emphases on the history of virus isolation and identification,tick vectors,and potential pathogenicity to humans and animals,including assigned species as well as the recently discovered and unassigned species.All these will promote our understanding of the diversity of TBVs,and will facilitate the further investigation of TBVs in association with both ticks and vertebrate hosts.
基金supported by the Science and Technology Basic Work Program (2013FY113500)the National Key Research and Development Program (2016YFE0113500) from the Ministry of Science and Technology of Chinathe European Union’s Horizon 2020 EVAg project (No 653316)
文摘Crimean-Congo hemorrhagic fever(CCHF)caused by the CCHF virus(CCHFV)is a tick-borne natural focal disease with a mortality rate of approximately 50%.CCHFV is widely prevalent in Africa,southern Asia,the Middle East,and southeast Europe.CCHF outbreaks have been reported previously in Xinjiang province,China,especially in its southern region.Epidemiological surveys conducted on ticks and animals have revealed the presence of CCHFV strains in ticks,rodents,and infected individuals from cities and counties in southern Xinjiang.Phylogenetic analyses revealed that the Chinese CCHFV strains belong to one genotype,based on complete sequences of the S segments of its negative-stranded RNA genome.The present study reports two new CCHFV strains isolated from Hyalomma asiaticum asiaticum ticks collected from Fukang City and Wujiaqu City in the northern region of Xinjiang.Viral characteristics and their evolutionary relationships were analyzed through metagenomic and reverse-transcription PCR analyses;these analyses indicated that the genotype of both strains was different from that of other Chinese strains.Furthermore,previous reports of CCHFV in Xinjiang were reviewed and phylogenetic analyses were performed.CCHFV was found to prevail in Fukang City in Junggar Basin for more than 20 years,and that Fukang City and Wujiaqu City are considered natural reservoirs of different genotypes of CCHFV strains.Our findings facilitate the understanding of CCHFV distribution in Xinjiang province and provide insights into the evolutionary relationships among Chinese CCHFV strains.
文摘Emerging infectious diseases are major threats to human health.Most severe viral disease outbreaks occur in developing regions where health conditions are poor.With increased international travel and business,the possibility of eventually transmitting infectious viruses between different countries is increasing.The most effective approach in preventing viral diseases is vaccination.However,vaccines are not currently available for numerous viral diseases.Viruslike particles(VLPs) are engineered vaccine candidates that have been studied for decades.VLPs are constructed by viral protein expression in various expression systems that promote the selfassembly of proteins into structures resembling virus particles.VLPs have antigenicity similar to that of the native virus,but are non-infectious as they lack key viral genetic material.VLP vaccines have attracted considerable research interest because they offer several advantages over traditional vaccines.Studies have shown that VLP vaccines can stimulate both humoral and cellular immune responses,which may offer effective antiviral protection.Here we review recent developments with VLP-based vaccines for several highly virulent emerging or re-emerging infectious diseases.The infectious agents discussed include RNA viruses from different virus families,such as the Arenaviridae,Bunyaviridae,Caliciviridae,Coronaviridae,Filoviridae,Flaviviridae,Orthomyxoviridae,Paramyxoviridae,and Togaviridae families.
基金the Ministry of Science and Technology of China (2013FY113500)the grants from the National Science Foundation of China (Nos.81460303,81760365)the State Key Laboratory of Virology of China (No.2015IOV003)
文摘The Crimean-Congo hemorrhagic fever virus(CCHFV),a member of the genus Orthonairovirus and family Nairoviridae,is transmitted by ticks and causes severe hemorrhagic disease in humans.To study the epidemiology of CCHFV in different ecosystems in Xinjiang,China,a total of 58,932 ticks were collected from Tarim Basin,Junggar Basin,Tianshan Mountain,and Altai Mountain from 2014 to 2017.Hyalomma asiaticum asiaticum was the dominant tick species in Tarim and Junggar basins,whereas Dermacentor nuttalli and Hyalomma detritum were found in Tianshan Mountain and Altai Mountain,respectively.Reverse transcription-polymerase chain reaction of the CCHFV small(S)genome segment was used for the molecular detection.The CCHFV-positive percentage was 5.26%,6.85%,1.94%,and 5.56% in Tarim Basin,Junggar Basin,Tianshan Mountain,and Altai Mountain,respectively.Sequences of the S segment were used for phylogenetic analysis and the results showed that the newly identified CCHFV strains belonged to two clades.Our study confirms that H.asiaticum asiaticum is the major vector of CCHFV in desert habitats which is consistent with previous studies,and also suggests that H.detritum and D.nuttalli are emerging vectors for CCHFV in Xinjiang.Moreover,this study reports the presence of CCHFV in the mountain habitat of Xinjiang for the first time,suggesting that future surveillance of CCHFV should also include mountainous areas.
基金Acknowtedgements We thank Dr Hong-Bing Shu (Wuhan University, China) for supplying reporter and expression plasmids.
This work was supported by the National Science Foundation of China (grant numbers 31125003 and 31321001), the Science and Technology Basic Work Program (grant number 2013FY113500), and the National Basic Research Program (973 Program) of China (grant numbers 2010CB530100 and 2013CB911101).
基金supported partly by the National Natural Science Foundation of China (No. 31371995 and 31621061)the Strategic Priority Research Program of the Chinese Academy of Sciences (grant XDB11030400)+1 种基金STS Project of the Chinese Academy of Sciences (grant KFJ-SW-STS143-3)the Hunan Provincial Natural Science Foundation for Distinguished Young Scholar of China (14JJ1023)
文摘No ascovirus isolated from China has been sequenced so far. Therefore, in this study, we aimed to sequence the genome of Heliothis virescens ascovirus 3h(Hv AV-3h) using the 454 pyrosequencing technology. The genome was found to be 190,519-bp long with a G+C content of 45.5%. We also found that it encodes 185 hypothetical open reading frames(ORFs) along with at least 50 amino acids, including 181 ORFs found in other ascoviruses and 4 unique ORFs. Gene-parity plots and phylogenetic analysis revealed a close relationship between Hv AV-3h and three other Hv AV-3a strains and a distant relationship with Spodoptera frugiperda ascovirus 1a(Sf AV-1a), Trichoplusia ni ascovirus 6a(Tn AV-6a), and Diadromus pulchellus ascovirus 4a(Dp AV-4a). Among the 185 potential genes encoded by the genome, 44 core genes were found in all the sequenced ascoviruses. In addition, 25 genes were found to be conserved in all ascoviruses except Dp AV-4a.In the Hv AV-3h genome, 24 baculovirus repeat ORFs(bros) were present, and the typical homologous repeat regions(hrs) were absent. This study supplies information important for understanding the conservation and functions of ascovirus genes as well as the variety of ascoviral genomes.
基金supported by the Science and Technology Basic Work Program (2013FY113500) from the Ministry of Science and Technology of China
文摘Crimean-Congo hemorrhagic fever virus(CCHFV) is a highly pathogenic tick-borne virus with a fatality rate of up to 50% in humans. CCHFV is widely distributed in countries around the world.Outbreaks of CCHFV infection in humans have occurred in prior years in Xinjiang Province, China.Epidemiological surveys have detected CCHFV RNA in ticks and animals; however, few isolates were identified. In this study, we identified and isolated a new CCHFV strain from Hyalomma asiaticum asiaticum ticks collected from north of Tarim Basin in Xinjiang, China. A preliminary investigation of infection and antigens expression of CCHFV was performed in newborn mice. The target tissues for CCHFV replication in newborn mice were identified. The analysis of the phylogenetic relationships with other Chinese strains suggested that diverse genotypes of CCHFV have circulated in Xinjiang for years. These findings provide important insights into our understanding of CCHFV infection and evolution as well as disease prevention and control for local residents.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB11030400)the National Natural Science Foundation of China(31130058,31621061)+1 种基金the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(QYZDJ-SSW-SMC021)the Virology Key Frontier Science Program of the State Key Laboratory of Virology(klv-2016-03)
文摘Baculoviruses are a family of arthropod-specific large DNA viruses that infect insect species belonging to the orders Lepidoptera,Hymenoptera and Diptera.In nature,occlusion-derived viruses(ODVs) initiate baculovirus primary infection in the midgut epithelium of insect hosts,and this process is largely dependent on a number of ODV envelope proteins designated as per os infectivity factors(PIFs).Interestingly,PIF homologs are also present in other invertebrate large DNA viruses,which is indicative that per os infection is an ancient and phylogenetically conserved entry mechanism shared by these viruses.Here,we review the advances in the knowledge of the functions of individual PIFs and recent discoveries about the PIF complex,and discuss the evolutionary implications of PIF homologs in invertebrate DNA viruses.Furthermore,future research highlights on the per os infection mechanism are also prospected.
基金supported by the Science and Technology Basic Work Program(2013FY113500)from the Ministry of Science and Technology of China
文摘Recent outbreaks of Zika virus(ZIKV) infections in Oceania's islands and the Americas were characterized by high numbers of cases and the spread of the virus to new areas. To better understand the origin of ZIKV, its epidemic history was reviewed. Although the available records and information are limited, two major genetic lineages of ZIKV were identified in previous studies.However, in this study, three lineages were identified based on a phylogenetic analysis of all virus sequences from Gen Bank, including those of the envelope protein(E) and non-structural protein 5(NS5) coding regions. The spatial and temporal distributions of the three identified ZIKV lineages and the recombination events and mechanisms underlying their divergence and evolution were further elaborated. The potential migration pathway of ZIKV was also characterized. Our findings revealed the central roles of two African countries, Senegal and Cote d'Ivoire, in ZIKV evolution and genotypic divergence. Furthermore, our results suggested that the outbreaks in Asia and the Pacific islands originated from Africa. The results provide insights into the geographic origins of ZIKV outbreaks and the spread of the virus, and also contribute to a better understanding of ZIKV evolution, which is important for the prevention and control of ZIKV infections.