Tick-borne encephalitis virus(TBEV)is an important tick-borne pathogen that poses as a serious public health concern.The coverage and immunogenicity of the currently available vaccines against TBEV are relatively low;...Tick-borne encephalitis virus(TBEV)is an important tick-borne pathogen that poses as a serious public health concern.The coverage and immunogenicity of the currently available vaccines against TBEV are relatively low;therefore,it is crucial to develop novel and effective vaccines against TBEV.The present study describes a novel strategy for the assembly of virus-like particles(VLPs)by co-expressing the structural(core/prM/E)and non-structural(NS2B/NS3Pro)proteins of TBEV.The efficacy of the VLPs was subsequently evaluated in C57BL/6 mice,and the resultant IgG serum could neutralize both Far-Eastern and European subtypes of TBEV.These findings indicated that the VLP-based vaccine elicited the production of cross-subtype reactive antibodies.The VLPs provided protection to mice lacking the type I interferon receptor(IFNAR^(-/-))against lethal TBEV challenge,with undetectable viral load in brain and intestinal tissues.Furthermore,the group that received the VLP vaccine did not exhibit significant pathological changes and the inflammatory factors were significantly suppressed compared to the control group.Immunization with the VLP vaccine induced the production of multiple-cytokine-producing antiviral CD4+T cells in vivo,including TNF-α^(+),IL-2^(+),and IFN-γ^(+)T cells.Altogether,the findings suggest that noninfectious VLPs can serve as a potentially safe and effective vaccine candidate against diverse subtypes of TBEV.展开更多
Tick-borne encephalitis(TBE)is a natural focal disease with fatal encephalitis induced by tick-borne encephalitis virus(TBEV),seriously threatening human and public health.Protection of TBE depends on vaccination with...Tick-borne encephalitis(TBE)is a natural focal disease with fatal encephalitis induced by tick-borne encephalitis virus(TBEV),seriously threatening human and public health.Protection of TBE depends on vaccination with inactivated vaccine,which requires high cost and multiple immunizations.Here,we construct genetically engineered bacterial-like particles(BLPs)as an effective TBEV vaccine with simplified immunizations and improved immune efficacy.The TBEV BLPs involve the combination of the gram-positive enhancer matrix from Lactococcus lactis,and TBEV envelope(E)protein expressed by genetically engineered recombinant baculovirus.The prepared TBEV BLPs can effectively stimulate the activation of dendritic cells to present the TBEV E proteins to T and B cells,leading to strong and durable cellular and humoral immune responses in mice.Surprisingly,the serum levels of specific IgG antibodies in mice remain about 10^(6)at 6 months after the secondary immunization.Overall,the TBEV BLPs can be used as a potent vaccine candidate,laying the foundation for developing novel TBEV genetically engineered vaccines.展开更多
Infectious diseases caused by arboviruses are a public health concern in Pakistan.However,studies on data prevalence and threats posed by arboviruses are limited.This study investigated the seroprevalence of arbovirus...Infectious diseases caused by arboviruses are a public health concern in Pakistan.However,studies on data prevalence and threats posed by arboviruses are limited.This study investigated the seroprevalence of arboviruses in a healthy population in Pakistan,including severe fever with thrombocytopenia syndrome virus(SFTSV),Crimean-Congo hemorrhagic fever virus(CCHFV),Tamdy virus(TAMV),and Karshi virus(KSIV)based on a newly established luciferase immunoprecipitation system(LIPS)assays,and Zika virus(ZIKV)by enzyme-linked immunosorbent assays(ELISA).Neutralizing activities against these arboviruses were further examined from the antibody positive samples.The results showed that the seroprevalence of SFTSV,CCHFV,TAMV,KSIV,and ZIKV was 17.37%,7.58%,4.41%,1.10%,and 6.48%,respectively,and neutralizing to SFTSV(1.79%),CCHFV(2.62%),and ZIKV(0.69%)were identified,as well as to the SFTSV-related Guertu virus(GTV,0.83%).Risk factors associated with the incidence of exposure and levels of antibody response were analyzed.Moreover,co-exposure to different arboviruses was demonstrated,as thirty-seven individuals were having antibodies against multiple viruses and thirteen showed neutralizing activity.Males,individuals aged40 years,and outdoor workers had a high risk of exposure to arboviruses.All these results reveal the substantial risks of infection with arboviruses in Pakistan,and indicate the threat from co-exposure to multiple arboviruses.The findings raise the need for further epidemiologic investigation in expanded regions and populations and the necessity to improve health surveillance in Pakistan.展开更多
Tick-borne encephalitis virus(TBEV) is a pathogenic virus known to cause central nervous system(CNS) diseases in humans, and has become an increasing public health threat nowadays. The rates of TBEV infection in the e...Tick-borne encephalitis virus(TBEV) is a pathogenic virus known to cause central nervous system(CNS) diseases in humans, and has become an increasing public health threat nowadays. The rates of TBEV infection in the endemic countries are increasing. However, there is no effective antiviral against the disease. This underscores the urgent need for tools to study the emergence and pathogenesis of TBEV and to accelerate the development of vaccines and antivirals. In this study, we reported an infectious c DNA clone of TBEV that was isolated in China(the WH2012 strain). A beta-globin intron was inserted in the coding region of nonstructural protein 1(NS1) gene to improve the stability of viral genome in bacteria. In mammalian cells, the inserted intron was excised and spliced precisely, which did not lead to the generation of inserted mutants. High titers of infectious progeny viruses were generated after the transfection of the infectious clone. The cDNA-derived TBEV replicated efficiently, and caused typical cytopathic effect(CPE) and plaques in BHK-21 cells. In addition, the CPE and growth curve of cDNA-derived virus were similar to that of its parental isolate in cells. Together, we have constructed the first infectious TBEV cDNA clone in China, and the clone can be used to investigate the genetic determinants of TBEV virulence and disease pathogenesis, and to develop countermeasures against the virus.展开更多
Lyme neuroborreliosis (LNB) in children is a challenging diagnosis based on clinical manifestations and laboratory findings. The aim of this study was to investigate whether herpes simplex virus (HSV) 1 or 2, varicell...Lyme neuroborreliosis (LNB) in children is a challenging diagnosis based on clinical manifestations and laboratory findings. The aim of this study was to investigate whether herpes simplex virus (HSV) 1 or 2, varicella zoster virus (VZV), enterovirus or tick-borne encephalitis virus (TBEV) could be identified in cerebrospinal fluid (CSF) or serum from children being evaluated for LNB, in order to elucidate whether such infectious diseases may be missed by the clinician. Methods: Ninety-nine pediatric patients (n = 99) were retrospectively included from a previous study on LNB in southeast of Sweden. They had been diagnosed as “Possible LNB” or “Not determined” due to negative Borrelia antibody index in CSF. Routine polymerase chain reaction (PCR) methods were used for detection of herpes viral RNA or enteroviral DNA in CSF. An ELISA assay was used for detection of anti-TBEV antibodies (IgM and IgG) in serum. Results: One patient showed elevated anti-TBEV IgM and IgG antibodies in serum, indicating a current TBE infection. No positive PCR reactions for HSV 1 or 2, VZV or enterovirus were detected in CSF from any of the patients. In conclusion, our results suggest that undiagnosed herpes- or enteroviral infections are unlikely to explain CNS symptoms in children being evaluated for LNB, whereas missed TBE infections may occur. TBEV serology should be included when evaluating children for LNB in TBE endemic areas.展开更多
Ticks are considered the second most common pathogen vectors transmitting a broad range of vital human and veterinary viruses.From 2017 to 2018,640 ticks were collected in eight different provinces in central and west...Ticks are considered the second most common pathogen vectors transmitting a broad range of vital human and veterinary viruses.From 2017 to 2018,640 ticks were collected in eight different provinces in central and western China.Six species were detected,including H.longicornis,De.everestianus,Rh.microplus,Rh.turanicus,Rh.sanguineous,and Hy.asiaticum.Sixty-four viral metagenomic libraries were constructed on the MiSeq Illumina platform,resulting in 13.44 G(5.88×10^(7))of 250-bp-end reads,in which 2,437,941 are viral reads.We found 27 nearly complete genome sequences,including 16 genome sequences encoding entire protein-coding regions(lack of 30 or 50 end non-coding regions)and complete viral genomes,distributed in the arboviral family(Chuviridae,Rhabdoviridae,Nairoviridae,Phenuiviridae,Flaviviridae,Iflaviridae)as well as Parvoviridae and Polyomaviridae that cause disease in mammals and even humans.In addition,13 virus sequences found in Chuviridae,Nairoviridae,Flaviviridae,Iflaviridae,Hepeviridae,Parvoviridae,and Polyomaviridae were identified as belonging to a new virus species in the identified viral genera.Besides,an epidemiological survey shows a high prevalence(9.38%and 15.63%)of two viruses(Ovine Copiparvovirus and Bovine parvovirus 2)in the tick cohort.展开更多
基金This work was supported by grants from the National Key Research and Development Program of China(grant number:2018YFA0507201 to X.W.C.)the National Science Foundation of China(grant number:32000111 to Q.Y.)the China Postdoctoral Science Foundation(grant number:2020T130021ZX to Q.Y.and grant number:2020M672580 to Q.Y.).
文摘Tick-borne encephalitis virus(TBEV)is an important tick-borne pathogen that poses as a serious public health concern.The coverage and immunogenicity of the currently available vaccines against TBEV are relatively low;therefore,it is crucial to develop novel and effective vaccines against TBEV.The present study describes a novel strategy for the assembly of virus-like particles(VLPs)by co-expressing the structural(core/prM/E)and non-structural(NS2B/NS3Pro)proteins of TBEV.The efficacy of the VLPs was subsequently evaluated in C57BL/6 mice,and the resultant IgG serum could neutralize both Far-Eastern and European subtypes of TBEV.These findings indicated that the VLP-based vaccine elicited the production of cross-subtype reactive antibodies.The VLPs provided protection to mice lacking the type I interferon receptor(IFNAR^(-/-))against lethal TBEV challenge,with undetectable viral load in brain and intestinal tissues.Furthermore,the group that received the VLP vaccine did not exhibit significant pathological changes and the inflammatory factors were significantly suppressed compared to the control group.Immunization with the VLP vaccine induced the production of multiple-cytokine-producing antiviral CD4+T cells in vivo,including TNF-α^(+),IL-2^(+),and IFN-γ^(+)T cells.Altogether,the findings suggest that noninfectious VLPs can serve as a potentially safe and effective vaccine candidate against diverse subtypes of TBEV.
基金National Key Research and Development Program of China,Grant/Award Number:2021YFC2600202Fundamental Research Funds for the Central Universities,Grant/Award Number:2132020KJC016。
文摘Tick-borne encephalitis(TBE)is a natural focal disease with fatal encephalitis induced by tick-borne encephalitis virus(TBEV),seriously threatening human and public health.Protection of TBE depends on vaccination with inactivated vaccine,which requires high cost and multiple immunizations.Here,we construct genetically engineered bacterial-like particles(BLPs)as an effective TBEV vaccine with simplified immunizations and improved immune efficacy.The TBEV BLPs involve the combination of the gram-positive enhancer matrix from Lactococcus lactis,and TBEV envelope(E)protein expressed by genetically engineered recombinant baculovirus.The prepared TBEV BLPs can effectively stimulate the activation of dendritic cells to present the TBEV E proteins to T and B cells,leading to strong and durable cellular and humoral immune responses in mice.Surprisingly,the serum levels of specific IgG antibodies in mice remain about 10^(6)at 6 months after the secondary immunization.Overall,the TBEV BLPs can be used as a potent vaccine candidate,laying the foundation for developing novel TBEV genetically engineered vaccines.
基金supported by the National Key Research and Development Programme of China[Grant Number 2021YFC2300900,2022YFC2302700]International Partnership Programme of the Bureau of International Cooperation,Chinese Academy of Sciences[Grant Number 153B42KYSB20200013]+1 种基金National Natural Science Foundation of China[Grant Number U22A20363]Biological Resources Programme,Chinese Academy of Sciences[Grant Number KFJ-BRP-017-74].
文摘Infectious diseases caused by arboviruses are a public health concern in Pakistan.However,studies on data prevalence and threats posed by arboviruses are limited.This study investigated the seroprevalence of arboviruses in a healthy population in Pakistan,including severe fever with thrombocytopenia syndrome virus(SFTSV),Crimean-Congo hemorrhagic fever virus(CCHFV),Tamdy virus(TAMV),and Karshi virus(KSIV)based on a newly established luciferase immunoprecipitation system(LIPS)assays,and Zika virus(ZIKV)by enzyme-linked immunosorbent assays(ELISA).Neutralizing activities against these arboviruses were further examined from the antibody positive samples.The results showed that the seroprevalence of SFTSV,CCHFV,TAMV,KSIV,and ZIKV was 17.37%,7.58%,4.41%,1.10%,and 6.48%,respectively,and neutralizing to SFTSV(1.79%),CCHFV(2.62%),and ZIKV(0.69%)were identified,as well as to the SFTSV-related Guertu virus(GTV,0.83%).Risk factors associated with the incidence of exposure and levels of antibody response were analyzed.Moreover,co-exposure to different arboviruses was demonstrated,as thirty-seven individuals were having antibodies against multiple viruses and thirteen showed neutralizing activity.Males,individuals aged40 years,and outdoor workers had a high risk of exposure to arboviruses.All these results reveal the substantial risks of infection with arboviruses in Pakistan,and indicate the threat from co-exposure to multiple arboviruses.The findings raise the need for further epidemiologic investigation in expanded regions and populations and the necessity to improve health surveillance in Pakistan.
基金This study was supported by grants from the National Key R&D Program of China(2018YFA0507201)。
文摘Tick-borne encephalitis virus(TBEV) is a pathogenic virus known to cause central nervous system(CNS) diseases in humans, and has become an increasing public health threat nowadays. The rates of TBEV infection in the endemic countries are increasing. However, there is no effective antiviral against the disease. This underscores the urgent need for tools to study the emergence and pathogenesis of TBEV and to accelerate the development of vaccines and antivirals. In this study, we reported an infectious c DNA clone of TBEV that was isolated in China(the WH2012 strain). A beta-globin intron was inserted in the coding region of nonstructural protein 1(NS1) gene to improve the stability of viral genome in bacteria. In mammalian cells, the inserted intron was excised and spliced precisely, which did not lead to the generation of inserted mutants. High titers of infectious progeny viruses were generated after the transfection of the infectious clone. The cDNA-derived TBEV replicated efficiently, and caused typical cytopathic effect(CPE) and plaques in BHK-21 cells. In addition, the CPE and growth curve of cDNA-derived virus were similar to that of its parental isolate in cells. Together, we have constructed the first infectious TBEV cDNA clone in China, and the clone can be used to investigate the genetic determinants of TBEV virulence and disease pathogenesis, and to develop countermeasures against the virus.
文摘Lyme neuroborreliosis (LNB) in children is a challenging diagnosis based on clinical manifestations and laboratory findings. The aim of this study was to investigate whether herpes simplex virus (HSV) 1 or 2, varicella zoster virus (VZV), enterovirus or tick-borne encephalitis virus (TBEV) could be identified in cerebrospinal fluid (CSF) or serum from children being evaluated for LNB, in order to elucidate whether such infectious diseases may be missed by the clinician. Methods: Ninety-nine pediatric patients (n = 99) were retrospectively included from a previous study on LNB in southeast of Sweden. They had been diagnosed as “Possible LNB” or “Not determined” due to negative Borrelia antibody index in CSF. Routine polymerase chain reaction (PCR) methods were used for detection of herpes viral RNA or enteroviral DNA in CSF. An ELISA assay was used for detection of anti-TBEV antibodies (IgM and IgG) in serum. Results: One patient showed elevated anti-TBEV IgM and IgG antibodies in serum, indicating a current TBE infection. No positive PCR reactions for HSV 1 or 2, VZV or enterovirus were detected in CSF from any of the patients. In conclusion, our results suggest that undiagnosed herpes- or enteroviral infections are unlikely to explain CNS symptoms in children being evaluated for LNB, whereas missed TBE infections may occur. TBEV serology should be included when evaluating children for LNB in TBE endemic areas.
基金funded by the National Key Research and Development Programs of China(No.2022YFC2603800)Jiangsu Provincial Key Research and Development Projects(No.BE2017693).
文摘Ticks are considered the second most common pathogen vectors transmitting a broad range of vital human and veterinary viruses.From 2017 to 2018,640 ticks were collected in eight different provinces in central and western China.Six species were detected,including H.longicornis,De.everestianus,Rh.microplus,Rh.turanicus,Rh.sanguineous,and Hy.asiaticum.Sixty-four viral metagenomic libraries were constructed on the MiSeq Illumina platform,resulting in 13.44 G(5.88×10^(7))of 250-bp-end reads,in which 2,437,941 are viral reads.We found 27 nearly complete genome sequences,including 16 genome sequences encoding entire protein-coding regions(lack of 30 or 50 end non-coding regions)and complete viral genomes,distributed in the arboviral family(Chuviridae,Rhabdoviridae,Nairoviridae,Phenuiviridae,Flaviviridae,Iflaviridae)as well as Parvoviridae and Polyomaviridae that cause disease in mammals and even humans.In addition,13 virus sequences found in Chuviridae,Nairoviridae,Flaviviridae,Iflaviridae,Hepeviridae,Parvoviridae,and Polyomaviridae were identified as belonging to a new virus species in the identified viral genera.Besides,an epidemiological survey shows a high prevalence(9.38%and 15.63%)of two viruses(Ovine Copiparvovirus and Bovine parvovirus 2)in the tick cohort.