In this study,a synthesized quadruple antigenic epitope gene region of the classical swine fever virus (CSFV)E2 glycoprotein was expressed in E.coli to a obtain target protein.This target protein was used as a coating...In this study,a synthesized quadruple antigenic epitope gene region of the classical swine fever virus (CSFV)E2 glycoprotein was expressed in E.coli to a obtain target protein.This target protein was used as a coating antigen to establish an indirect ELISA for specifically detecting anti-CSFV antibodies in serum samples from pigs.The P/N cut-off value of this assay was 1.92 by receiver operating characteristic curve(ROC)analysis based on 30 negative sera and 80 positive samples.The test gave 97.5%sensitivity and 96.7%specificity compared with the indirect hemagglutination(IHA)test.The inter-assay and intra-assay coefficients of variation (CVs)for 16 sera were both≤6.8%.No cross-reactivity between the coating antigen and anti-bovine viral diarrhoea virus(BVDV)antibodies was observed.展开更多
Coronaviruses are widespread in nature and can infect mammals and poultry,making them a public health concern.Globally,prevention and control of emerging and re-emerging animal coronaviruses is a great challenge.The m...Coronaviruses are widespread in nature and can infect mammals and poultry,making them a public health concern.Globally,prevention and control of emerging and re-emerging animal coronaviruses is a great challenge.The mecha-nisms of virus-mediated immune responses have important implications for research on virus prevention and control.The antigenic epitope is a chemical group capable of stimulating the production of antibodies or sensitized lympho-cytes,playing an important role in antiviral immune responses.Thus,it can shed light on the development of diagnos-tic methods and novel vaccines.Here,we have reviewed advances in animal coronavirus antigenic epitope research,aiming to provide a reference for the prevention and control of animal and human coronaviruses.展开更多
Influenza virus can rapidly change its antigenicity, via mutation in the hemagglutinin(HA) protein, to evade host immunity. The emergence of the novel human-infecting avian H7N9 virus in China has caused widespread co...Influenza virus can rapidly change its antigenicity, via mutation in the hemagglutinin(HA) protein, to evade host immunity. The emergence of the novel human-infecting avian H7N9 virus in China has caused widespread concern. However, evolution of the antigenicity of this virus is not well understood. Here, we inferred the antigenic epitopes of the HA protein from all H7 viruses, based on the five well-characterized HA epitopes of the human H3N2 virus. By comparing the two major H7 phylogenetic lineages, i.e., the Eurasian lineage and the North American lineage, we found that epitopes A and B are more frequently mutated in the Eurasian lineage, while epitopes B and C are more frequently mutated in the North American lineage. Furthermore, we found that the novel H7N9 virus(derived from the Eurasian lineage) isolated in China in the year 2013, contains six frequently mutated sites on epitopes that include site 135, which is located in the receptor binding domain. This indicates that the novel H7N9 virus that infects human may already have been subjected to gradual immune pressure and receptor-binding variation. Our results not only provide insights into the antigenic evolution of the H7 virus but may also help in the selection of suitable vaccine strains.展开更多
Porcine reproductive and respiratory syndrome virus(PRRSV)infection causes significant economic loss to the global pig industry.Genotype 1 and 2 PRRSV(PRRSV-1 and-2)infections have been reported in China,Europe and Am...Porcine reproductive and respiratory syndrome virus(PRRSV)infection causes significant economic loss to the global pig industry.Genotype 1 and 2 PRRSV(PRRSV-1 and-2)infections have been reported in China,Europe and America.For accurate prevention,nanobodies were first used as diagnostic reagents for PRRSV typing.In this study three nanobodies targeting both PRRSV-1 and-2,two targeting PRRSV-1 and three targeting PRRSV-2,were screened and produced.To develop two competitive ELISAs(cELISAs),the g1-2-PRRSV-Nb3-HRP nanobody was chosen for the g1-2-cELISA,to detect common antibodies against PRRSV-1 and-2,and the g1-PRRSV-Nb136-HRP nanobody was chosen for the g1-cELISA,to detect anti-PRRSV-1 antibodies.The two cELISAs were developed using PRRSV-1-N protein as coating antigen,and the amounts for both were 100 ng/well.The optimized dilution of testing pig sera was 1:20,the optimized reaction times were 30 min,and the colorimetric reaction times were 15 min.Then,the cut-off values of the g1-2-cELISA and g1-cELISA were 26.6%and 35.6%,respectively.Both of them have high sensitivity,strong specificity,good repeatability,and stability.In addition,for the 1534 clinical pig sera,an agreement rate of 99.02%(Kappa values=0.97)was determined between the g1-2-cELISA and the commercial IDEXX ELISA kit.For the g1-cELSIA,it can specifically detect anti-PRRSV-1 antibodies in the clinical pig sera.Importantly,combining two nanobody-based cELISAs can differentially detect antibodies against PRRSV-1 and-2.展开更多
[ Objective] To investigate the immunogenicity of main antigen epitope of RHDV （ Rabbit haemorrhagic disease virus） VP60 expressed in a prokaryotic system. [ Method] The major antigen epitope gene of RHDV VP60 was a...[ Objective] To investigate the immunogenicity of main antigen epitope of RHDV （ Rabbit haemorrhagic disease virus） VP60 expressed in a prokaryotic system. [ Method] The major antigen epitope gene of RHDV VP60 was amplified by RT-PCR. It was cloned into pET-28b （ ＋ ） and expressed in E. coli Rosetta strain. The recombinant protein was detected by Western blot. The pudfied recombinant protein was used to immunize rabbits in order to observe its immunogenicity. [ Result] Western blot analysis revealed a clear band at approximately 24.0 kDa. The purified recom- binant protein reacted with the purified RHDV in ELISA. [ Conclusion] The prokaryotically expressed main antigen epitope of RHDV VP60 shows good immunogenicity.展开更多
Respiratory syncytial virus(RSV)is a significant cause of acute lower respiratory tract infection(ALRTI)in children underfive years of age.Between 2017 and 2021,396 complete sequences of the RSV F gene were obtained fro...Respiratory syncytial virus(RSV)is a significant cause of acute lower respiratory tract infection(ALRTI)in children underfive years of age.Between 2017 and 2021,396 complete sequences of the RSV F gene were obtained from 500 RSV-positive throat swabs collected from ten hospitals across nine provinces in China.In addition,151 sequences from China were sourced from GenBank and GISAID,making a total of 549 RSV F gene sequences subjected to analysis.Phylogenetic and genetic diversity analyses revealed that the RSV F genes circulating in China from 2017 to 2021 have remained relatively conserved,although some amino acids(AAs)have undergone changes.AA mutations with frequencies10%were identified at six sites and the p27 region:V384I(site I),N276S(site II),R213S(siteØ),and K124N(p27)for RSV A;F45L(site I),M152I/L172Q/S173 L/I185V/K191R(site V),and R202Q/I206M/Q209R(siteØ)for RSV B.Comparing mutational frequencies in RSV-F before and after 2020 revealed minor changes for RSV A,while the K191R,I206M,and Q209R frequencies increased by over 10%in RSV B.Notably,the nirsevimab-resistant mutation,S211N in RSV B,increased in frequency from 0%to 1.15%.Both representative strains aligned with the predicted RSV-F structures of their respective prototypes exhibited similar conformations,with low root-mean-square deviation values.These results could provide foundational data from China for the development of RSV mAbs and vaccines.展开更多
An effective vaccine for human immunodeficiency virus(HIV) is urgently needed to prevent HIV infection and progression to acquired immune deficiency syndrome(AIDS). As glycosylation of viral proteins becomes better un...An effective vaccine for human immunodeficiency virus(HIV) is urgently needed to prevent HIV infection and progression to acquired immune deficiency syndrome(AIDS). As glycosylation of viral proteins becomes better understood, carbohydrate-based antiviral vaccines against special viruses have attracted much attention. Significant efforts in carbohydrate synthesis and immunogenicity research have resulted in the development of multiple carbohydrate-based HIV vaccines. This review summarizes recent advances in synthetic carbohydrate-based vaccines design strategies and the applications of these vaccines in the prevention of HIV.展开更多
文摘In this study,a synthesized quadruple antigenic epitope gene region of the classical swine fever virus (CSFV)E2 glycoprotein was expressed in E.coli to a obtain target protein.This target protein was used as a coating antigen to establish an indirect ELISA for specifically detecting anti-CSFV antibodies in serum samples from pigs.The P/N cut-off value of this assay was 1.92 by receiver operating characteristic curve(ROC)analysis based on 30 negative sera and 80 positive samples.The test gave 97.5%sensitivity and 96.7%specificity compared with the indirect hemagglutination(IHA)test.The inter-assay and intra-assay coefficients of variation (CVs)for 16 sera were both≤6.8%.No cross-reactivity between the coating antigen and anti-bovine viral diarrhoea virus(BVDV)antibodies was observed.
基金supported by the Natural Science Foundation of Zhejiang Province(Q23C180006)the Zhejiang A&F University Talent Initiative Project(118-203402005901).
文摘Coronaviruses are widespread in nature and can infect mammals and poultry,making them a public health concern.Globally,prevention and control of emerging and re-emerging animal coronaviruses is a great challenge.The mecha-nisms of virus-mediated immune responses have important implications for research on virus prevention and control.The antigenic epitope is a chemical group capable of stimulating the production of antibodies or sensitized lympho-cytes,playing an important role in antiviral immune responses.Thus,it can shed light on the development of diagnos-tic methods and novel vaccines.Here,we have reviewed advances in animal coronavirus antigenic epitope research,aiming to provide a reference for the prevention and control of animal and human coronaviruses.
基金supported by the National Basic Research Program of China(2015CB910501)the Major National Earmark Project for Infectious Diseases(2014ZX10004002-001)+1 种基金the Key Research Program of the Chinese Academy of Sciences(KJZD-EW-L09-1-2)to Jiang Tai Jiaothe National Natural Science Foundation of China(31470273)to Wu Ai Ping
文摘Influenza virus can rapidly change its antigenicity, via mutation in the hemagglutinin(HA) protein, to evade host immunity. The emergence of the novel human-infecting avian H7N9 virus in China has caused widespread concern. However, evolution of the antigenicity of this virus is not well understood. Here, we inferred the antigenic epitopes of the HA protein from all H7 viruses, based on the five well-characterized HA epitopes of the human H3N2 virus. By comparing the two major H7 phylogenetic lineages, i.e., the Eurasian lineage and the North American lineage, we found that epitopes A and B are more frequently mutated in the Eurasian lineage, while epitopes B and C are more frequently mutated in the North American lineage. Furthermore, we found that the novel H7N9 virus(derived from the Eurasian lineage) isolated in China in the year 2013, contains six frequently mutated sites on epitopes that include site 135, which is located in the receptor binding domain. This indicates that the novel H7N9 virus that infects human may already have been subjected to gradual immune pressure and receptor-binding variation. Our results not only provide insights into the antigenic evolution of the H7 virus but may also help in the selection of suitable vaccine strains.
基金funded by grants from the National Key R&D Program of China(2023YFD1800304)the National Natural Science Foundation of China to QZ(32273041)+1 种基金the Natural Science Foundation of Shaanxi Province of China(2022JC-12)the Central Public-interest Scientific Institution Basal Research Fund,National Data Center of Animal Health.
文摘Porcine reproductive and respiratory syndrome virus(PRRSV)infection causes significant economic loss to the global pig industry.Genotype 1 and 2 PRRSV(PRRSV-1 and-2)infections have been reported in China,Europe and America.For accurate prevention,nanobodies were first used as diagnostic reagents for PRRSV typing.In this study three nanobodies targeting both PRRSV-1 and-2,two targeting PRRSV-1 and three targeting PRRSV-2,were screened and produced.To develop two competitive ELISAs(cELISAs),the g1-2-PRRSV-Nb3-HRP nanobody was chosen for the g1-2-cELISA,to detect common antibodies against PRRSV-1 and-2,and the g1-PRRSV-Nb136-HRP nanobody was chosen for the g1-cELISA,to detect anti-PRRSV-1 antibodies.The two cELISAs were developed using PRRSV-1-N protein as coating antigen,and the amounts for both were 100 ng/well.The optimized dilution of testing pig sera was 1:20,the optimized reaction times were 30 min,and the colorimetric reaction times were 15 min.Then,the cut-off values of the g1-2-cELISA and g1-cELISA were 26.6%and 35.6%,respectively.Both of them have high sensitivity,strong specificity,good repeatability,and stability.In addition,for the 1534 clinical pig sera,an agreement rate of 99.02%(Kappa values=0.97)was determined between the g1-2-cELISA and the commercial IDEXX ELISA kit.For the g1-cELSIA,it can specifically detect anti-PRRSV-1 antibodies in the clinical pig sera.Importantly,combining two nanobody-based cELISAs can differentially detect antibodies against PRRSV-1 and-2.
文摘[ Objective] To investigate the immunogenicity of main antigen epitope of RHDV （ Rabbit haemorrhagic disease virus） VP60 expressed in a prokaryotic system. [ Method] The major antigen epitope gene of RHDV VP60 was amplified by RT-PCR. It was cloned into pET-28b （ ＋ ） and expressed in E. coli Rosetta strain. The recombinant protein was detected by Western blot. The pudfied recombinant protein was used to immunize rabbits in order to observe its immunogenicity. [ Result] Western blot analysis revealed a clear band at approximately 24.0 kDa. The purified recom- binant protein reacted with the purified RHDV in ELISA. [ Conclusion] The prokaryotically expressed main antigen epitope of RHDV VP60 shows good immunogenicity.
基金supported by the National Key Research and Development Program of China(grant number 2023YFC2306002)National Science and Technology Major Projects(grant number 2017ZX10104001-005-010)CAMS Innovation Fund for Medical Sciences(CIFMS)(Grant Number 2019-I2M-5-026)and Funding for Reform and Development of Beijing Municipal Health Commission.
文摘Respiratory syncytial virus(RSV)is a significant cause of acute lower respiratory tract infection(ALRTI)in children underfive years of age.Between 2017 and 2021,396 complete sequences of the RSV F gene were obtained from 500 RSV-positive throat swabs collected from ten hospitals across nine provinces in China.In addition,151 sequences from China were sourced from GenBank and GISAID,making a total of 549 RSV F gene sequences subjected to analysis.Phylogenetic and genetic diversity analyses revealed that the RSV F genes circulating in China from 2017 to 2021 have remained relatively conserved,although some amino acids(AAs)have undergone changes.AA mutations with frequencies10%were identified at six sites and the p27 region:V384I(site I),N276S(site II),R213S(siteØ),and K124N(p27)for RSV A;F45L(site I),M152I/L172Q/S173 L/I185V/K191R(site V),and R202Q/I206M/Q209R(siteØ)for RSV B.Comparing mutational frequencies in RSV-F before and after 2020 revealed minor changes for RSV A,while the K191R,I206M,and Q209R frequencies increased by over 10%in RSV B.Notably,the nirsevimab-resistant mutation,S211N in RSV B,increased in frequency from 0%to 1.15%.Both representative strains aligned with the predicted RSV-F structures of their respective prototypes exhibited similar conformations,with low root-mean-square deviation values.These results could provide foundational data from China for the development of RSV mAbs and vaccines.
基金the National Science Foundation for Young Scientists of China(No.21302068)the Natural Science Foundation of Jiangsu Province,China(No.BK20130127,BK20140154,and BK20150140)+1 种基金the Public Health Research Center at Jiangnan University(No.JUPH201502)Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of Education,Jiangnan University(KLCCB-KF201504)
文摘An effective vaccine for human immunodeficiency virus(HIV) is urgently needed to prevent HIV infection and progression to acquired immune deficiency syndrome(AIDS). As glycosylation of viral proteins becomes better understood, carbohydrate-based antiviral vaccines against special viruses have attracted much attention. Significant efforts in carbohydrate synthesis and immunogenicity research have resulted in the development of multiple carbohydrate-based HIV vaccines. This review summarizes recent advances in synthetic carbohydrate-based vaccines design strategies and the applications of these vaccines in the prevention of HIV.
