PCV2 is considered the main pathogen of porcine circovirus diseases and porcine circovirus-associated diseases(PCVD/PCVAD). However, the exact mechanism underlying PCVD/PCVAD is currently unknown. Mouse models of PCV2...PCV2 is considered the main pathogen of porcine circovirus diseases and porcine circovirus-associated diseases(PCVD/PCVAD). However, the exact mechanism underlying PCVD/PCVAD is currently unknown. Mouse models of PCV2 are valuable experimental tools that can shed light on the pathogenesis of infection and will enable the evaluation of antiviral agents and vaccine candidates. In this review, we discuss the current state of knowledge of mouse models used in PCV2 research that has been performed to date, highlighting their strengths and limitations, as well as prospects for future PCV2 studies.展开更多
Porcine circovirus type 2(PCV2),which serves as a major causative agent of PCV2-associated diseases and causes severe loss to the pig industry worldwide,can dysregulate the immune response and induce immunosuppression...Porcine circovirus type 2(PCV2),which serves as a major causative agent of PCV2-associated diseases and causes severe loss to the pig industry worldwide,can dysregulate the immune response and induce immunosuppression in PCV2-infected pigs.Similar to PCV2(porcine circovirus type 3(PCV3),a newly identified swine circovirus which might be closely associated with porcine dermatitis and nephropathy syndrome,reproductive disorder,and multisystemic inflammatoty responses,also interferes with host immune defense.Interaction between host immune system and PCVs is considered to be a crucial determinant of pathogenicity in pigs.Here,we sought to briefly discuss the current knowledge regarding the interaction of porcine circovirus type 2 and/or 3 with host immune cells and immune responses to better depict the viral immunomodulatory capacity,pathogenic mechanisms,and the future research direction in host immune responses to infection with PCV2 and PCV3.展开更多
Porcine circovirus type 3(PCV3),which was first detected in the United States of America in 2015,is a potential threat to the swine industry.However,the prevalence of PCV3 in Shanxi Province,China,is unclear.In this r...Porcine circovirus type 3(PCV3),which was first detected in the United States of America in 2015,is a potential threat to the swine industry.However,the prevalence of PCV3 in Shanxi Province,China,is unclear.In this research,the prevalence and genetic diversity of PCV3 were investigated in above area.Lung tissue samples(n=491)from 19 pig slaughterhouses across 11 cities throughout Shanxi Province were analyzed for PCV3 infection by PCR in 2019.The results showed that PCV3 positive rates in slaughterhouses and individuals were 100%(19/19)and 86.76%(426/491),respectively.PCV2 and PCV3 double-positive rates in slaughterhouses and individuals were 100%(19/19)and 59.27%(291/491),respectively.PCR positive samples were further sequenced and 8 PCV3 isolates were identified.The nucleotide homology of these isolates with other PCV3 isolates in NCBI database was 97.45-99.90%.A phylogenetic analysis,based on the complete genomic sequence and ORF2,divided these PCV3 strains into 2 major groups.Based on A24A/and R27/K amino acid mutations of capsid protein,the 8 identified PCV3 strains were separated to 2 clades.This was the first detailed investigation into the epidemiology of PCV3 in Shanxi Province.Our findings enabled us to assess the possibility of widespread transmission from this region.Thus,current findings establish a basis for further studies of genetic variations in PCV3 strains circulating in China.展开更多
We developed an assay for the detection and quantitation of porcine circovirus type 2 (PCV2) with the SYBR Green I-based real-time PCR. The real-time PCR provides a broad dynamic range, detecting from 103 to 1011 copi...We developed an assay for the detection and quantitation of porcine circovirus type 2 (PCV2) with the SYBR Green I-based real-time PCR. The real-time PCR provides a broad dynamic range, detecting from 103 to 1011 copies of DNA per reaction. No cross-reactions were found in specimens containing PCV1. Because of the high sensitivity and specificity of the assay with a relatively rapid and simple procedure, real-time PCR can be used as a routine assay for the clinical diagnosis of PCV2 infection. In this study we applied real-time PCR assay to 80 clinical samples, collected from 40 pigs with postweaning multisystemic wasting syndrome (PMWS) and 40 healthy pigs in comparison with conventional PCR assay. In 56 of 80 samples, PCV2 DNA was de-tected by conventional PCR assay. All samples positive for PCV2 DNA in conventional PCR assay were also positive in real-time assay, and 12 of 24 samples that tested negative for PCV2 DNA in the conventional assay were tested positive in real-time PCR assay. Real-time PCR assay increased the number of samples in which PCV2 was detected by 15%. It is, therefore, considered to be a useful tool for the detection of PCV2.展开更多
Four species of porcine circoviruses(PCV1–4)have been reported to circulate in Chinese domestic pigs,while the epizootiology of these viruses in free-ranging wild boars in China remains unknown.In this study,tissue a...Four species of porcine circoviruses(PCV1–4)have been reported to circulate in Chinese domestic pigs,while the epizootiology of these viruses in free-ranging wild boars in China remains unknown.In this study,tissue and serum samples collected from diseased or apparently healthy wild boars between 2018 and 2020 in 19 regions of China were tested for the prevalence of PCV1–4 infections.Positive rates of PCV1,PCV2,and PCV3 DNA in the tissue samples of Chinese wild boars were 1.6%(4/247),58.3%(144/247),and 10.9%(27/247)respectively,with none positive for PCV4.Sequence analysis of viral genome showed that the four PCV1 strains distributed in Hunan and Inner Mongolia shared 97.5%–99.6%sequence identity with global distributed reference strains.Comparison of the ORF2 gene sequences showed that 80 PCV2 strains widely distributed in 18 regions shared 79.5%–100%sequence identity with reference strains from domestic pigs and wild boars,and were grouped into PCV2a(7),PCV2b(31)and PCV2d(42).For PCV3,17 sequenced strains shared 97.2%–100%nucleotide identity at the genomic level and could be divided into PCV3a(3),PCV3b(2)and PCV3c(12)based on the phylogeny of ORF2 gene sequences.Serological data revealed antibody positive rates against PCV1 and PCV2 of 11.4%(19/167)and 53.9%(90/167)respectively.The data obtained in this study improved our understanding about the epidemiological situations of PCVs infection in free-ranging wild boars in China and will be valuable for the prevention and control of diseases caused by PCVs infection.展开更多
基金National Key Research and Development Program of China,Grant/Award Number:2017YFD0500103National Natural Science Foundation of China,Grant/Award Number:31772747,31272385+3 种基金Jilin Province Science and Technology Development Projects,Grant/Award Number:20150204077NYGraduate Innovation Fund of Jilin Universitythe Program for Changjiang Scholarsthe University Innovative Research Team,Grant/Award Number:IRT1248
文摘PCV2 is considered the main pathogen of porcine circovirus diseases and porcine circovirus-associated diseases(PCVD/PCVAD). However, the exact mechanism underlying PCVD/PCVAD is currently unknown. Mouse models of PCV2 are valuable experimental tools that can shed light on the pathogenesis of infection and will enable the evaluation of antiviral agents and vaccine candidates. In this review, we discuss the current state of knowledge of mouse models used in PCV2 research that has been performed to date, highlighting their strengths and limitations, as well as prospects for future PCV2 studies.
基金This study was supported by a grant from the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Porcine circovirus type 2(PCV2),which serves as a major causative agent of PCV2-associated diseases and causes severe loss to the pig industry worldwide,can dysregulate the immune response and induce immunosuppression in PCV2-infected pigs.Similar to PCV2(porcine circovirus type 3(PCV3),a newly identified swine circovirus which might be closely associated with porcine dermatitis and nephropathy syndrome,reproductive disorder,and multisystemic inflammatoty responses,also interferes with host immune defense.Interaction between host immune system and PCVs is considered to be a crucial determinant of pathogenicity in pigs.Here,we sought to briefly discuss the current knowledge regarding the interaction of porcine circovirus type 2 and/or 3 with host immune cells and immune responses to better depict the viral immunomodulatory capacity,pathogenic mechanisms,and the future research direction in host immune responses to infection with PCV2 and PCV3.
基金This research was supported by funding from the Key Research and Development Projea Key Program of Shanxi Province,China(grant no.201703D211001).
文摘Porcine circovirus type 3(PCV3),which was first detected in the United States of America in 2015,is a potential threat to the swine industry.However,the prevalence of PCV3 in Shanxi Province,China,is unclear.In this research,the prevalence and genetic diversity of PCV3 were investigated in above area.Lung tissue samples(n=491)from 19 pig slaughterhouses across 11 cities throughout Shanxi Province were analyzed for PCV3 infection by PCR in 2019.The results showed that PCV3 positive rates in slaughterhouses and individuals were 100%(19/19)and 86.76%(426/491),respectively.PCV2 and PCV3 double-positive rates in slaughterhouses and individuals were 100%(19/19)and 59.27%(291/491),respectively.PCR positive samples were further sequenced and 8 PCV3 isolates were identified.The nucleotide homology of these isolates with other PCV3 isolates in NCBI database was 97.45-99.90%.A phylogenetic analysis,based on the complete genomic sequence and ORF2,divided these PCV3 strains into 2 major groups.Based on A24A/and R27/K amino acid mutations of capsid protein,the 8 identified PCV3 strains were separated to 2 clades.This was the first detailed investigation into the epidemiology of PCV3 in Shanxi Province.Our findings enabled us to assess the possibility of widespread transmission from this region.Thus,current findings establish a basis for further studies of genetic variations in PCV3 strains circulating in China.
文摘We developed an assay for the detection and quantitation of porcine circovirus type 2 (PCV2) with the SYBR Green I-based real-time PCR. The real-time PCR provides a broad dynamic range, detecting from 103 to 1011 copies of DNA per reaction. No cross-reactions were found in specimens containing PCV1. Because of the high sensitivity and specificity of the assay with a relatively rapid and simple procedure, real-time PCR can be used as a routine assay for the clinical diagnosis of PCV2 infection. In this study we applied real-time PCR assay to 80 clinical samples, collected from 40 pigs with postweaning multisystemic wasting syndrome (PMWS) and 40 healthy pigs in comparison with conventional PCR assay. In 56 of 80 samples, PCV2 DNA was de-tected by conventional PCR assay. All samples positive for PCV2 DNA in conventional PCR assay were also positive in real-time assay, and 12 of 24 samples that tested negative for PCV2 DNA in the conventional assay were tested positive in real-time PCR assay. Real-time PCR assay increased the number of samples in which PCV2 was detected by 15%. It is, therefore, considered to be a useful tool for the detection of PCV2.
基金This work was supported by grants from the National Natural Science Foundation of China to Z Tu(31902307)National Key Research and Development Program of China to C Tu(2017YFD0500104)Wildlife Borne Infectious Diseases Monitoring Project of the State Forestry and Grassland Administration of China.
文摘Four species of porcine circoviruses(PCV1–4)have been reported to circulate in Chinese domestic pigs,while the epizootiology of these viruses in free-ranging wild boars in China remains unknown.In this study,tissue and serum samples collected from diseased or apparently healthy wild boars between 2018 and 2020 in 19 regions of China were tested for the prevalence of PCV1–4 infections.Positive rates of PCV1,PCV2,and PCV3 DNA in the tissue samples of Chinese wild boars were 1.6%(4/247),58.3%(144/247),and 10.9%(27/247)respectively,with none positive for PCV4.Sequence analysis of viral genome showed that the four PCV1 strains distributed in Hunan and Inner Mongolia shared 97.5%–99.6%sequence identity with global distributed reference strains.Comparison of the ORF2 gene sequences showed that 80 PCV2 strains widely distributed in 18 regions shared 79.5%–100%sequence identity with reference strains from domestic pigs and wild boars,and were grouped into PCV2a(7),PCV2b(31)and PCV2d(42).For PCV3,17 sequenced strains shared 97.2%–100%nucleotide identity at the genomic level and could be divided into PCV3a(3),PCV3b(2)and PCV3c(12)based on the phylogeny of ORF2 gene sequences.Serological data revealed antibody positive rates against PCV1 and PCV2 of 11.4%(19/167)and 53.9%(90/167)respectively.The data obtained in this study improved our understanding about the epidemiological situations of PCVs infection in free-ranging wild boars in China and will be valuable for the prevention and control of diseases caused by PCVs infection.
