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Hinojosa Y, Liniger M, García-Nicolás O, Gerber M, Rajaratnam A, Muñoz-González S, Coronado L, Frías MT, Perera CL, Ganges L, Ruggli N. Evolutionary-Related High- and Low-Virulent Classical Swine Fever Virus Isolates Reveal Viral Determinants of Virulence. Viruses 2024; 16:147. [PMID: 38275957 PMCID: PMC10820463 DOI: 10.3390/v16010147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/13/2024] [Accepted: 01/15/2024] [Indexed: 01/27/2024] Open
Abstract
Classical swine fever (CSF) has been eradicated from Western and Central Europe but remains endemic in parts of Central and South America, Asia, and the Caribbean. CSF virus (CSFV) has been endemic in Cuba since 1993, most likely following an escape of the highly virulent Margarita/1958 strain. In recent years, chronic and persistent infections with low-virulent CSFV have been observed. Amino acid substitutions located in immunodominant epitopes of the envelope glycoprotein E2 of the attenuated isolates were attributed to positive selection due to suboptimal vaccination and control. To obtain a complete picture of the mutations involved in attenuation, we applied forward and reverse genetics using the evolutionary-related low-virulent CSFV/Pinar del Rio (CSF1058)/2010 (PdR) and highly virulent Margarita/1958 isolates. Sequence comparison of the two viruses recovered from experimental infections in pigs revealed 40 amino acid differences. Interestingly, the amino acid substitutions clustered in E2 and the NS5A and NS5B proteins. A long poly-uridine sequence was identified previously in the 3' untranslated region (UTR) of PdR. We constructed functional cDNA clones of the PdR and Margarita strains and generated eight recombinant viruses by introducing single or multiple gene fragments from Margarita into the PdR backbone. All chimeric viruses had comparable replication characteristics in porcine monocyte-derived macrophages. Recombinant PdR viruses carrying either E2 or NS5A/NS5B of Margarita, with 36 or 5 uridines in the 3'UTR, remained low virulent in 3-month-old pigs. The combination of these elements recovered the high-virulent Margarita phenotype. These results show that CSFV evolution towards attenuated variants in the field involved mutations in both structural and non-structural proteins and the UTRs, which act synergistically to determine virulence.
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Affiliation(s)
- Yoandry Hinojosa
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, 3012 Bern, Switzerland
- Centro Nacional de Sanidad Agropecuaria (CENSA), San José de las Lajas 32700, Cuba; (M.T.F.); (C.L.P.)
| | - Matthias Liniger
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
| | - Obdulio García-Nicolás
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
| | - Markus Gerber
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
| | - Anojen Rajaratnam
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
| | - Sara Muñoz-González
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (S.M.-G.); (L.C.); (L.G.)
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
| | - Liani Coronado
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (S.M.-G.); (L.C.); (L.G.)
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
| | - María Teresa Frías
- Centro Nacional de Sanidad Agropecuaria (CENSA), San José de las Lajas 32700, Cuba; (M.T.F.); (C.L.P.)
| | - Carmen Laura Perera
- Centro Nacional de Sanidad Agropecuaria (CENSA), San José de las Lajas 32700, Cuba; (M.T.F.); (C.L.P.)
| | - Llilianne Ganges
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Barcelona, Spain; (S.M.-G.); (L.C.); (L.G.)
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
| | - Nicolas Ruggli
- Division of Virology, Institute of Virology and Immunology IVI, 3147 Mittelhäusern, Switzerland; (Y.H.); (M.L.); (O.G.-N.); (M.G.)
- Department of Infectious Diseases and Pathobiology (DIP), University of Bern, 3012 Bern, Switzerland
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S. Muhsin S, A. Al-Safar M, Mahmood SA. Men's ND1 gene genetic makeup Toxoplasmosis and Oligospermia affecting couples' infertility. BIONATURA 2023. [DOI: 10.21931/rb/2023.08.01.84] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023] Open
Abstract
Introduction: Toxoplasma infection was higher in infertile couples than fertile couples, probably due to anti-sperm antibodies that were higher in couples with Toxoplasmosis. Investigations of T. gondii infections in men with infertility showed that among 100 cases of men's infertility, 36% were serologically positive for Toxoplasma-IgG and IgM. It has been concluded that T. gondii can affect men's fertility and result in infertility. Materials and Methods: Selective infertile males were asked about days of sexual abstinence. Seminal fluid samples were collected following a minimum of 2 days and a maximum of 7 days from abstinence. Every patient was given a clean, wide mouth, sterile, dry, graduated plastic and warm disposable container. The samples were obtained by masturbation in a private room near the semen analysis lab to reduce seminal exposure to temperature fluctuations and control the time from collection to analysis. Results: For the ND1 gene, samples of 8 different fertility groups have been sequenced. These sequences have been compared to reference sequences taken from the NCBI database. Several mutations in various nucleotide positions of the ND1 regions have been detected in samples from multiple groups. The base substitution has been positioned on the nucleotides (nts) 3480, 3567, 3591, 3693, and 4216. The T to C evolution was notorious at nt 3480 in ND1 genes. The SNP was detected in an asthenospermia human (Sample code: 010480).
Keywords: Sequence, ND1 gen, Oligospermia Toxoplasmosis, Couples infertility
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Affiliation(s)
- Salwa S. Muhsin
- Department of Community, Medical Technical Institute, Baghdad, Middle Technical, University, Iraq (MTU)
| | - Montaha A. Al-Safar
- Department of Community, Medical Technical Institute, Baghdad, Middle Technical, University, Iraq (MTU)
| | - Sarah A. Mahmood
- Department of Community, Medical Technical Institute, Baghdad, Middle Technical, University, Iraq (MTU)
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Sun YY, Liu KS, Zhang C, Ni Z, Zhu YC, Bao HL, Chen L, Ye WC, Hua JG, Huo SX, Wang HY, Yun T, Bao ED. Recombinant pseudorabies virus (PRV) expressing stabilized E2 of classical swine fever virus (CSFV) protects against both PRV and CSFV. Antiviral Res 2023; 211:105548. [PMID: 36702445 DOI: 10.1016/j.antiviral.2023.105548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/05/2023] [Accepted: 01/19/2023] [Indexed: 01/25/2023]
Abstract
Pseudorabies (PR) and classical swine fever (CSF) are economically important infectious diseases of pigs. Most pig farms in China are immunized against these two diseases. Here, we describe a stabilized E2 protein as an immunogen inserted into the PRV genome as a bivalent live virus-vectored vaccine. The E2 protein has 48 variant sites, there are 2-5 candidate amino acids per variant site, and the relative energy contribution of each amino acid to E2 energy was calculated. Combined substitutions of amino acids at the neighbor variant site (neighbor substitution) were performed to obtain the E2 protein sequence with the lowest energy (stabilized E2). Multiple amino acid substitutions at 48 variant sites were performed, and the results were consistent with neighbor substitutions. The stabilized E2 sequence was obtained, and its energy decreased by 22 Rosetta Energy Units (REUs) compared with the original sequence. After the recombinant PRV expressing stabilized E2 of CSFV was constructed, the secretion efficiency of stabilized E2 was increased by 2.97 times, and the thermal stability was increased by 10.5 times. Immunization of mice resulted in a 2-fold increase in antibody production, and a balanced antibody level against subtype 1.1 and subtype 2.1d E2 was achieved. In rabbits immunized, the lethal challenge of PRV-ZJ and the fever response induced by CSFV could be prevented simultaneously. These findings suggest that rPRV-muta/287aaE2 is a promising bivalent vaccine against CSFV and PRV infections.
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Affiliation(s)
- Yang-Yang Sun
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China; Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Ke-Shu Liu
- Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Cun Zhang
- Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Zheng Ni
- Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Yin-Chu Zhu
- Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Hai-Li Bao
- Fujian Provincial Key Laboratory of Reproductive Health Research, School of Medicine, Xiamen University, Xiamen, China
| | - Liu Chen
- Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Wei-Cheng Ye
- Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Jiong-Gang Hua
- Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Su-Xin Huo
- Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Hong-Yu Wang
- Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Tao Yun
- Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China; State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Animal Husbandry and Veterinary Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China.
| | - En-Dong Bao
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, China.
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Xia YJ, Xu L, Zhao JJ, Li YX, Wu RZ, Song XP, Zhao QZ, Liu YB, Wang Q, Zhang QY. Development of a quadruple PCR-based gene microarray for detection of vaccine and wild-type classical swine fever virus, African swine fever virus and atypical porcine pestivirus. Virol J 2022; 19:201. [PMID: 36447230 PMCID: PMC9708128 DOI: 10.1186/s12985-022-01933-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 11/24/2022] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND Classical swine fever (CSF), African swine fever (ASF), and atypical porcine pestivirus (APPV) are acute, virulent, and contagious viral diseases currently hampering the pig industry in China, which result in mummification or stillbirths in piglets and mortality in pigs. Diagnostic assays for the differentiation of infection and vaccination of CSFV, in addition to the detection of ASFV and APPV, are urgently required for better prevention, control, and elimination of these viral diseases in China. METHODS A quadruple PCR-based gene microarray assay was developed in this study to simultaneously detect wild-type and vaccine CSFV strains, ASFV and APPV according to their conserved regions. Forty-two laboratory-confirmed samples, including positive samples of 10 other swine viral diseases, were tested using this assay to confirm its high specificity. RESULTS This assay's limit of detections (LODs) for the wild-type and vaccine CSFV were 6.98 and 6.92 copies/µL. LODs for ASFV and APPV were 2.56 × 10 and 1.80 × 10 copies/µL, respectively. When compared with standard RT-PCR or qPCR for CSFV (GB/T 26875-2018), ASFV (MARR issue No.172), or APPV (CN108611442A) using 219 clinical samples, the coincidence was 100%. The results showed that this assay with high sensitivity could specifically distinguish ASFV, APPV, and CSFV, including CSFV infection and immunization. CONCLUSION This assay provides a practical, simple, economic, and reliable test for the rapid detection and accurate diagnosis of the three viruses and may have good prospects for application in an epidemiological investigation, prevention, and control and elimination of these three diseases.
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Affiliation(s)
- Ying-ju Xia
- grid.418540.cChina Institute of Veterinary Drug Control, Beijing, 100081 People’s Republic of China
| | - Lu Xu
- grid.418540.cChina Institute of Veterinary Drug Control, Beijing, 100081 People’s Republic of China
| | - Jun-jie Zhao
- grid.418540.cChina Institute of Veterinary Drug Control, Beijing, 100081 People’s Republic of China
| | - Yuan-xi Li
- grid.418540.cChina Institute of Veterinary Drug Control, Beijing, 100081 People’s Republic of China
| | - Rui-zhi Wu
- grid.418540.cChina Institute of Veterinary Drug Control, Beijing, 100081 People’s Republic of China
| | - Xiang-peng Song
- grid.418540.cChina Institute of Veterinary Drug Control, Beijing, 100081 People’s Republic of China
| | - Qi-zu Zhao
- grid.418540.cChina Institute of Veterinary Drug Control, Beijing, 100081 People’s Republic of China
| | - Ye-bing Liu
- grid.418540.cChina Institute of Veterinary Drug Control, Beijing, 100081 People’s Republic of China
| | - Qin Wang
- grid.418540.cChina Institute of Veterinary Drug Control, Beijing, 100081 People’s Republic of China
| | - Qian-yi Zhang
- grid.418540.cChina Institute of Veterinary Drug Control, Beijing, 100081 People’s Republic of China
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Bohórquez JA, Wang M, Díaz I, Alberch M, Pérez-Simó M, Rosell R, Gladue DP, Borca MV, Ganges L. The FlagT4G Vaccine Confers a Strong and Regulated Immunity and Early Virological Protection against Classical Swine Fever. Viruses 2022; 14:v14091954. [PMID: 36146761 PMCID: PMC9502879 DOI: 10.3390/v14091954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/30/2022] [Accepted: 08/30/2022] [Indexed: 11/20/2022] Open
Abstract
Control of classical swine fever virus (CSFV) in endemic countries relies on vaccination, mostly using vaccines that do not allow for differentiation of vaccinated from infected animals (DIVA). FlagT4G vaccine is a novel candidate that confers robust immunity and shows DIVA capabilities. The present study assessed the immune response elicited by FlagT4G and its capacity to protect pigs for a short time after vaccination. Five days after a single dose of FlagT4G vaccine, animals were challenged with a highly virulent CSFV strain. A strong, but regulated, interferon-α response was found after vaccination. Vaccinated animals showed clinical and virological protection against the challenge, in the absence of antibody response at 5 days post-vaccination. Upon challenge, a rapid rise in the titers of CSFV neutralizing antibodies and an increase in the IFN-γ producing cells were noticed in all vaccinated-challenged pigs. Meanwhile, unvaccinated pigs showed severe clinical signs and high viral replication, being euthanized before the end of the trial. These animals were unable to generate neutralizing antibodies and IFN-γ responses after the CSFV challenge. The results from the present study assert the fast and efficient protection by FlagT4G, a highly promising tool for CSFV control worldwide.
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Affiliation(s)
- José Alejandro Bohórquez
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61820, USA
| | - Miaomiao Wang
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
| | - Ivan Díaz
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
| | - Mònica Alberch
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
| | - Marta Pérez-Simó
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
| | - Rosa Rosell
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- Departament d’Acció Climàtica, Alimentació i Agenda Rural, Generalitat de Catalunya, 08007 Barcelona, Spain
| | - Douglas P. Gladue
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA
- Correspondence: (D.P.G.); (M.V.B.); (L.G.)
| | - Manuel V. Borca
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA
- Correspondence: (D.P.G.); (M.V.B.); (L.G.)
| | - Llilianne Ganges
- WOAH Reference Laboratory for Classical Swine Fever, IRTA-CReSA, 08193 Bellaterra, Spain
- Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- IRTA, Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), 08193 Barcelona, Spain
- Correspondence: (D.P.G.); (M.V.B.); (L.G.)
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A Novel Competitive ELISA for Specifically Measuring and Differentiating Immune Responses to Classical Swine Fever C-Strain Vaccine in Pigs. Viruses 2022; 14:v14071544. [PMID: 35891524 PMCID: PMC9315997 DOI: 10.3390/v14071544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/07/2022] [Accepted: 07/13/2022] [Indexed: 11/17/2022] Open
Abstract
Classical swine fever can be controlled effectively by vaccination with C-strain vaccine. In this study, we developed a novel competitive enzyme-linked immunosorbent assay (cELISA) based on a C-strain Erns specific monoclonal antibody (mAb 1504), aiming to serologically measure immune responses to C-strain vaccine in pigs, and finally to make the C-strain become a DIVA-compatible vaccine. The cELISA system was established based on the strategy that mAb 1504 will compete with the C-strain induced antibodies in the pig serum to bind the C-strain Erns protein. The cELISA was optimized and was further evaluated by testing different categories of pig sera. It can efficiently differentiate C-strain immunized from wild-type CSFV-infected pigs and lacks cross-reaction with other common swine viruses and viruses in genus Pestivirus such as Bovine viral diarrhea virus (BVDV). The C-strain antibody can be tested in pigs 7-14 days post vaccination with this cELISA. The sensitivity and specificity of the established cELISA were 100% (95% confidence interval: 95.60 to 100%) and 100% (95% confidence interval: 98.30 to 100%), respectively. This novel cELISA is a reliable tool for specifically measuring and differentiating immune responses to C-strain vaccine in pigs. By combining with the wild-type CSFV-specific infection tests, it can make the C-strain have DIVA capability.
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Fei Z, Jiao A, Xu M, Wu J, Wang Y, Yu J, Lu L, Jiang W, Zhu G, Sun W, Chen Z, Zhang Y, Ren S, Liu F, Zhang L. Genetic diversity and evolution of goose astrovirus in the east of China. Transbound Emerg Dis 2022; 69:e2059-e2072. [PMID: 35384346 DOI: 10.1111/tbed.14542] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/20/2022] [Accepted: 03/28/2022] [Indexed: 12/01/2022]
Abstract
Goose astrovirus (GAstV), an agent of fatal visceral gout in goslings, has been widely circulating in eastern China since 2017, but little is known about its genetic diversity and systematic evolution. In this study, we isolated and sequenced nine nearly full-length GAstV genomes and conducted comprehensive genetic diversity and evolutionary analysis and compared them with other reported GAstV sequences. Our results indicated that two genotypic species of GAstV were circulating in China, and GAstV-2 subgenotype II-c had arisen as the dominant genotype in Shandong province and across the whole country. Multiple alignment of GAstV amino acid sequences revealed several characteristic mutations in GAstV-2 II-c strains, as well as additional residues in the nine new isolates which varied over time. Phylogenetic analysis of three open reading frames demonstrated different evolutionary histories. Evidence of natural recombination was also detected in GAstV, with most of the recombination occurring in the GAstV-2 II-c subgenotype. Molecular adaptation analyses revealed that the evolution of GAstV was shaped by strong negative selection, although a number of amino acids, which potentially affect host infection and cell entry, were subjected to positive pressure. Overall, these findings improve our understanding of the epidemiology and evolution of GAstV and may help in the development of vaccines and diagnostics. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Zhiguo Fei
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
| | - Anqi Jiao
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
| | - Minli Xu
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
| | - Jiaqiang Wu
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China.,College of Life Sciences, Shandong Normal University, 88 Wenhua East Road, Jinan, Shandong, China
| | - Yu Wang
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
| | - Jiang Yu
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
| | - Lu Lu
- Emerging Economic Formats Research Institute, Shandong Management University, 3500 Dingxiang Road, Jinan, Shandong, China
| | - Wanchun Jiang
- College of Life Sciences and Food Engineering, Hebei University of Engineering, 199 Guangming South Street, Handan, Hebei, China
| | - Gaungwei Zhu
- Qilu Normal University, 2 Wenbo Road, Jinan, Shandong, China
| | - Wenbo Sun
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
| | - Zhi Chen
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
| | - Yuyu Zhang
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
| | - Sufang Ren
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
| | - Fei Liu
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
| | - Lin Zhang
- Shandong Key Laboratory of Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Science, 202 Gongye North Road, Jinan, Shandong, China
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Nguyen NH, Thi Phuong BN, Nguyen TQ, Do Tien D, Nguyen Thi MD, Nguyen MN. Genotypic diversity of CSFV field strains: A silent risk reduces vaccination efficacy of CSFV vaccines in Vietnam. Virology 2022; 571:39-45. [DOI: 10.1016/j.virol.2022.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 01/07/2022] [Accepted: 04/07/2022] [Indexed: 10/18/2022]
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Genetic diversity and molecular characterization of classical swine fever virus envelope protein genes E2 and E rns circulating in Vietnam from 2017 to 2019. INFECTION GENETICS AND EVOLUTION 2021; 96:105140. [PMID: 34781037 DOI: 10.1016/j.meegid.2021.105140] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 11/01/2021] [Accepted: 11/09/2021] [Indexed: 11/22/2022]
Abstract
Classical swine fever virus (CSFV) is an RNA virus that incurs severe economic costs to swine industries worldwide. This study was conducted to investigate the genetic diversity among CSFV strains circulating in Vietnam, with a focus on their genetic variants relative to four vaccine strains. Samples from clinical cases were collected from different provinces of Central and Southern Vietnam from 2017 to 2019. 21 CSFV-positive samples were selected for amplification and sequencing of the full-length Erns and E2 genes. Phylogenetic analyses of these two genes showed that most CSFV strains circulating in Central and Southern Vietnam from 2017 to 2019 belong to subgroup 2.1c, whereas the remaining strains cluster into subgroup 2.2. All CSFV field strains in this study were genetically distant from group 1 strains. Analysis of the E2 and Erns genes indicated that all CSFV field strains have low sequence identity with the vaccine strains (80-83.5% and 82.3-86% sequence identity for E2 and Erns, respectively). Likewise, amino acid-level sequence analysis showed 87.3-91.1% and 87.6-91.6% sequence identity for E2 and Erns, respectively. Together, our findings indicate that CSFV strains circulating in Vietnam belong to subtypes 2.2 and 2.1c, and we also provide novel insights into the epidemiology, molecular characteristics, genetic diversity, and evolution of these circulating CSFV strains.
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10
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Patil SS, Indrabalan UB, Suresh KP, Shome BR. Analysis of codon usage bias of classical swine fever virus. Vet World 2021; 14:1450-1458. [PMID: 34316191 PMCID: PMC8304411 DOI: 10.14202/vetworld.2021.1450-1458] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 04/21/2021] [Indexed: 11/22/2022] Open
Abstract
Background and Aim: Classical swine fever (CSF), caused by CSF virus (CSFV), is a highly contagious disease in pigs causing 100% mortality in susceptible adult pigs and piglets. High mortality rate in pigs causes huge economic loss to pig farmers. CSFV has a positive-sense RNA genome of 12.3 kb in length flanked by untranslated regions at 5’ and 3’ end. The genome codes for a large polyprotein of 3900 amino acids coding for 11 viral proteins. The 1300 codons in the polyprotein are coded by different combinations of three nucleotides which help the infectious agent to evolve itself and adapt to the host environment. This study performed and employed various methods/techniques to estimate the changes occurring in the process of CSFV evolution by analyzing the codon usage pattern. Materials and Methods: The evolution of viruses is widely studied by analyzing their nucleotides and coding regions/codons using various methods. A total of 115 complete coding regions of CSFVs including one complete genome from our laboratory (MH734359) were included in this study and analysis was carried out using various methods in estimating codon usage bias and evolution. This study elaborates on the factors that influence the codon usage pattern. Results: The effective number of codons (ENC) and relative synonymous codon usage showed the presence of codon usage bias. The mononucleotide (A) has a higher frequency compared to the other mononucleotides (G, C, and T). The dinucleotides CG and CC are underrepresented and overrepresented. The codons CGT was underrepresented and AGG was overrepresented. The codon adaptation index value of 0.71 was obtained indicating that there is a similarity in the codon usage bias. The principal component analysis, ENC-plot, Neutrality plot, and Parity Rule 2 plot produced in this article indicate that the CSFV is influenced by the codon usage bias. The mutational pressure and natural selection are the important factors that influence the codon usage bias. Conclusion: The study provides useful information on the codon usage analysis of CSFV and may be utilized to understand the host adaptation to virus environment and its evolution. Further, such findings help in new gene discovery, design of primers/probes, design of transgenes, determination of the origin of species, prediction of gene expression level, and gene function of CSFV. To the best of our knowledge, this is the first study on codon usage bias involving such a large number of complete CSFVs including one sequence of CSFV from India.
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Affiliation(s)
- Sharanagouda S Patil
- ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Yelahanka, Bengaluru, Karnataka, India
| | - Uma Bharathi Indrabalan
- ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Yelahanka, Bengaluru, Karnataka, India
| | | | - Bibek Ranjan Shome
- ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Yelahanka, Bengaluru, Karnataka, India
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11
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Genotyping and Molecular Characterization of Classical Swine Fever Virus Isolated in China during 2016-2018. Viruses 2021; 13:v13040664. [PMID: 33921513 PMCID: PMC8069065 DOI: 10.3390/v13040664] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 04/06/2021] [Accepted: 04/07/2021] [Indexed: 12/17/2022] Open
Abstract
Classical swine fever (CSF) is a highly contagious disease of swine caused by classical swine fever virus (CSFV). For decades the disease has been controlled in China by a modified live vaccine (C-strain) of genotype 1. The emergent genotype 2 strains have become predominant in China in the past years that are genetically distant from the vaccine strain. Here, we aimed to evaluate the current infectious status of CSF, and for this purpose 24 isolates of CSFV were identified from different areas of China during 2016–2018. Phylogenetic analysis of NS5B, E2 and full genome revealed that the new isolates were clustered into subgenotype 2.1d and 2.1b, while subgenotype 2.1d was predominant. Moreover, E2 and Erns displayed multiple variations in neutralizing epitope regions. Furthermore, the new isolates exhibited capacity to escape C-strain-derived antibody neutralization compared with the Shimen strain (genotype 1). Potential positive selection sites were identified in antigenic regions of E2 and Erns, which are related with antibody binding affinity. Recombination events were predicted in the new isolates with vaccine strains in the E2 gene region. In conclusion, the new isolates showed molecular variations and antigenic alterations, which provide evidence for the emergence of vaccine-escaping mutants and emphasize the need of updated strategies for CSF control.
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12
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Suárez-Pedroso M, Sordo-Puga Y, Sosa-Teste I, Rodriguez-Molto MP, Naranjo-Valdés P, Sardina-González T, Santana-Rodríguez E, Montero-Espinosa C, Frías-Laporeaux MT, Fuentes-Rodríguez Y, Pérez-Pérez D, Oliva-Cárdenas A, Pereda CL, González-Fernández N, Bover-Fuentes E, Vargas-Hernández M, Duarte CA, Estrada-García MP. Novel chimeric E2CD154 subunit vaccine is safe and confers long lasting protection against classical swine fever virus. Vet Immunol Immunopathol 2021; 234:110222. [PMID: 33690056 DOI: 10.1016/j.vetimm.2021.110222] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 02/19/2021] [Accepted: 03/02/2021] [Indexed: 10/22/2022]
Abstract
E2CD154 is a vaccine candidate against classical swine fever (CSF) based on a chimeric protein composed of the E2 glycoprotein fused to porcine CD154 antigen, and formulated in the oil adjuvant Montanide™ ISA 50 V2. This vaccine confers early protection in pigs and prevents vertical transmission in pregnant sows. The objectives of this study were to assess the safety of this immunogen in piglets, to compare several doses of antigen in the formulation, and to study the duration of the immunity provided by this vaccine for up to 9 months. Three trials were conducted by immunizing pigs with a two-dose regime of the vaccine. Challenge experiments were carried out with the highly pathogenic Margarita strain. No local or systemic adverse effects were documented, and neither macroscopic nor microscopic pathological findings were observed in the vaccinated animals. The three antigen doses explored were safe and induced CSF protective neutralizing antibodies. The dose of 50 μg was selected for further development because it provided the best clinical and virological protection. Finally, this protective immunity was sustained for at least 9 months. This study demonstrates that E2CD154 vaccine is safe; defines a vaccine dose of 50 μg antigen, and evidences the capacity of this vaccine to confer long term protection from CSFV infection for up to 9 months post- vaccination. These findings complement previous data on the evaluation of this vaccine candidate, and suggest that E2CD154 is a promising alternative to modified live vaccines in CSF endemic areas.
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Affiliation(s)
- Marisela Suárez-Pedroso
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba.
| | - Yusmel Sordo-Puga
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba
| | - Iliana Sosa-Teste
- Centro para la Producción de Animales de Laboratorio (CENPALAB), Centro de Toxicología Experimental (CETEX), Cuba
| | | | | | - Talía Sardina-González
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba
| | - Elaine Santana-Rodríguez
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba
| | - Carlos Montero-Espinosa
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba
| | | | - Yohandy Fuentes-Rodríguez
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba
| | - Danny Pérez-Pérez
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba
| | - Ayme Oliva-Cárdenas
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba
| | - Carmen Laura Pereda
- Centro Nacional de Sanidad Agropecuaria (CENSA), Apdo 10, San José de Las Lajas, Havana, Cuba
| | - Nemecio González-Fernández
- Departamento de Desarrollo de Procesos, Centro de Ingeniería Genética y Biotecnología (CIGB), Camagüey, Cuba
| | - Eddy Bover-Fuentes
- Departamento de Desarrollo de Procesos, Centro de Ingeniería Genética y Biotecnología (CIGB), Camagüey, Cuba
| | - Milagros Vargas-Hernández
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba
| | - Carlos A Duarte
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba
| | - Mario Pablo Estrada-García
- Departamento de Biotecnología Animal, Centro de Ingeniería Genética y Biotecnología (CIGB), Havana, Cuba
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13
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Ganges L, Crooke HR, Bohórquez JA, Postel A, Sakoda Y, Becher P, Ruggli N. Classical swine fever virus: the past, present and future. Virus Res 2020; 289:198151. [PMID: 32898613 DOI: 10.1016/j.virusres.2020.198151] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 08/24/2020] [Accepted: 08/28/2020] [Indexed: 12/22/2022]
Abstract
Classical swine fever (CSF) is among the most relevant viral epizootic diseases of swine. Due to its severe economic impact, CSF is notifiable to the world organisation for animal health. Strict control policies, including systematic stamping out of infected herds with and without vaccination, have permitted regional virus eradication. Nevertheless, CSF virus (CSFV) persists in certain areas of the world and has re-emerged regularly. This review summarizes the basic established knowledge in the field and provides a comprehensive and updated overview of the recent advances in fundamental CSFV research, diagnostics and vaccine development. It covers the latest discoveries on the genetic diversity of pestiviruses, with implications for taxonomy, the progress in understanding disease pathogenesis, immunity against acute and persistent infections, and the recent findings in virus-host interactions and virulence determinants. We also review the progress and pitfalls in the improvement of diagnostic tools and the challenges in the development of modern and efficacious marker vaccines compatible with serological tests for disease surveillance. Finally, we highlight the gaps that require research efforts in the future.
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Affiliation(s)
- Llilianne Ganges
- OIE Reference Laboratory for Classical Swine Fever, Institute of Agrifood Research and Technology, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain.
| | - Helen R Crooke
- Virology Department, Animal and Plant Health Agency, APHA-Weybridge, Woodham Lane, New Haw, Addlestone, KT15 3NB, UK
| | - Jose Alejandro Bohórquez
- OIE Reference Laboratory for Classical Swine Fever, Institute of Agrifood Research and Technology, Centre de Recerca en Sanitat Animal (CReSA), 08193 Barcelona, Spain
| | - Alexander Postel
- EU & OIE Reference Laboratory for Classical Swine Fever, Institute of Virology, University of Veterinary Medicine, Hannover, Buenteweg 17, 30559 Hannover, Germany
| | - Yoshihiro Sakoda
- Laboratory of Microbiology, Faculty of Veterinary Medicine, Hokkaido University, Kita 18 Nishi 9, Kita-ku, Sapporo, 060-0818, Japan
| | - Paul Becher
- EU & OIE Reference Laboratory for Classical Swine Fever, Institute of Virology, University of Veterinary Medicine, Hannover, Buenteweg 17, 30559 Hannover, Germany
| | - Nicolas Ruggli
- The Institute of Virology and Immunology IVI, Mittelhäusern, Switzerland; Department of Infectious Diseases and Pathobiology, University of Bern, Bern, Switzerland
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14
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Lo Presti A, Rezza G, Stefanelli P. Selective pressure on SARS-CoV-2 protein coding genes and glycosylation site prediction. Heliyon 2020; 6:e05001. [PMID: 32984566 PMCID: PMC7505600 DOI: 10.1016/j.heliyon.2020.e05001] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 07/07/2020] [Accepted: 09/17/2020] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND An outbreak of a febrile respiratory illness due to the newly discovered Coronavirus, SARS-CoV-2, was initially detected in mid-December 2019 in the city of Wuhan, Hubei province (China). The virus then spread to most countries in the world. As an RNA virus, SARS-CoV-2 may acquire mutations that may be fixed. The aim of this study was to evaluate the selective pressure acting on SARS-CoV-2 protein coding genes. METHODS Mutations and glycosylation site prediction were analyzed in SARS-CoV-2 genomes (from 464 to 477 sequences). RESULTS Selective pressure on surface glycoprotein (S) revealed one positively selected site (AA 943), located outside the receptor binding domain (RBD). Mutation analysis identified five residues on the surface glycoprotein, with variations (AA positions 367, 458, 477, 483, 491) located inside the RDB. Positive selective pressure was identified in nsp2, nsp3, nsp4, nsp6, nsp12, helicase, ORF3a, ORF8, and N sub-sets. A total of 22 predicted N-glycosylation positions were found in the SARS-CoV-2 surface glycoprotein; one of them, 343N, was located within the RBD. One predicted N-glycosylation site was found in the M protein and 4 potential O-glycosylation sites in specific protein 3a sequences. CONCLUSION Overall, the data showed positive pressure and mutations acting on specific protein coding genes. These findings may provide useful information on: i) markers for vaccine design, ii) new therapeutic approach, iii) information to implement mutagenesis experiments to inhibit SARS-CoV-2 cell entry. The negative selection identified in SARS-CoV-2 protein coding genes may help the identification of highly conserved regions useful to implement new future diagnostic protocols.
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Affiliation(s)
| | - Giovanni Rezza
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
- Health Prevention Directorate, Ministry of Health, Rome, Italy
| | - Paola Stefanelli
- Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
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15
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Cloning and Identification of PK15 Cells for Enhanced Replication of Classical Swine Fever Virus. J Vet Res 2020; 64:9-14. [PMID: 32258794 PMCID: PMC7105985 DOI: 10.2478/jvetres-2020-0020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 02/27/2020] [Indexed: 11/20/2022] Open
Abstract
Introduction Classical swine fever virus (CSFV) causes an economically important and highly contagious disease of pigs, leading to economic losses around the world. Attenuated live vaccines with CSFV antigens have played an important role in the prevention and control of the disease. Porcine kidney 15 (PK15) cells have been widely used for the propagation of CSFV, but this cell line is not efficient or homogeneously susceptible to viral infection. Material and Methods To achieve a homogeneous PK15 cell line which enabled high titre replication of CSFV, we used the limiting dilution cell cloning method. Results We developed two cell clones, PK15-1A6 and PK15-3B1, which respectively have high- and low-permissive phenotypes to CSFV infection. The PK15-1A6, PK15-3B1, and PK15 parent cells showed different characteristics in cell proliferation rate, susceptibility to CSFV infection, and CSFV production. The mean virus titres per millilitre reflected by TCID50 values in PK15-1A6, PK15-3B1, and PK15 parent cells were 106.85, 103.63, and 104.74, respectively. Conclusion The PK15-1A6 cell clone is more permissive to CSFV infection than the PK15 parent cells. The screened high-permissive cells will be useful for CSFV propagation and vaccine development in vitro, and facilitate research on the pathogenicity of CSFV.
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16
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Wang L, Mi S, Madera R, Ganges L, Borca MV, Ren J, Cunningham C, Cino-Ozuna AG, Li H, Tu C, Gong W, Shi J. A neutralizing monoclonal antibody-based competitive ELISA for classical swine fever C-strain post-vaccination monitoring. BMC Vet Res 2020; 16:14. [PMID: 31937302 PMCID: PMC6958719 DOI: 10.1186/s12917-020-2237-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 01/08/2020] [Indexed: 01/17/2023] Open
Abstract
Background Virus neutralization test (VNT) is widely used for serological survey of classical swine fever (CSF) and efficacy evaluation of CSF vaccines. However, VNT is a time consuming procedure that requires cell culture and live virus manipulation. C-strain CSF vaccine is the most frequently used vaccine for CSF control and prevention. In this study, we presented a neutralizing monoclonal antibody (mAb) based competitive enzyme-linked immunosorbent assay (cELISA) with the emphasis on the replacement of VNT for C-strain post–vaccination monitoring. Results One monoclonal antibody (6B211) which has potent neutralizing activity against C-strain was generated. A novel cELISA was established and optimized based on the strategy that 6B211 can compete with C-strain induced neutralizing antibodies in pig serum to bind capture antigen C-strain E2. By testing C-strain VNT negative pig sera (n = 445) and C-strain VNT positive pig sera (n = 70), the 6B211 based cELISA showed 100% sensitivity (95% confidence interval: 94.87 to 100%) and 100% specificity (95% confidence interval: 100 to 100%). The C-strain antibody can be tested in pigs as early as 7 days post vaccination with the cELISA. By testing pig sera (n = 139) in parallel, the cELISA showed excellent agreement (Kappa = 0.957) with VNT. The inhibition rate of serum samples in the cELISA is highly correlated with their titers in VNT (r2 = 0.903, p < 0.001). In addition, intra- and inter-assays of the cELISA exhibited acceptable repeatability with low coefficient of variations (CVs). Conclusions This novel cELISA demonstrated excellent agreement and high level correlation with VNT. It is a reliable tool for sero-monitoring of C-strain vaccination campaign because it is a rapid, simple, safe and cost effective assay that can be used to monitor vaccination-induced immune response at the population level.
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Affiliation(s)
- Lihua Wang
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Shijiang Mi
- Key Laboratory of Zoonoses Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China.,Institute of Military Veterinary, Academy of Military Medical Sciences, Changchun, Jilin, China
| | - Rachel Madera
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Llilianne Ganges
- OIE Reference Laboratory for Classical Swine Fever, IRTA-CReSA, Barcelona, Spain
| | - Manuel V Borca
- Plum Island Animal Disease Center, ARS, USDA, Orient Point, New York, USA
| | - Jingqiang Ren
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Chase Cunningham
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Ada G Cino-Ozuna
- Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Hongwei Li
- School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, Guangdong, China
| | - Changchun Tu
- Key Laboratory of Zoonoses Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China.,Institute of Military Veterinary, Academy of Military Medical Sciences, Changchun, Jilin, China
| | - Wenjie Gong
- Key Laboratory of Zoonoses Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, Jilin, China. .,Institute of Military Veterinary, Academy of Military Medical Sciences, Changchun, Jilin, China.
| | - Jishu Shi
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA.
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17
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Gong W, Li J, Wang Z, Sun J, Mi S, Xu J, Cao J, Hou Y, Wang D, Huo X, Sun Y, Wang P, Yuan K, Gao Y, Zhou X, He S, Tu C. Commercial E2 subunit vaccine provides full protection to pigs against lethal challenge with 4 strains of classical swine fever virus genotype 2. Vet Microbiol 2019; 237:108403. [PMID: 31585656 DOI: 10.1016/j.vetmic.2019.108403] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/28/2019] [Accepted: 08/28/2019] [Indexed: 10/26/2022]
Abstract
Classical swine fever (CSF) still threatens the swine industry in China, with genotype 2 isolates of CSFV dominating the epizootics. In 2018 the first E2 subunit marker vaccine against CSFV (Tian Wen Jing, TWJ-E2®), containing a baculovirus-expressed E2 glycoprotein of a genotype 1.1 vaccine strain, was officially licensed in China and commercialized. To evaluate the cross-protective efficacy of TWJ-E2 against different virulent genotype 2 Chinese field isolates (2.1b, 2.1c, 2.1 h, and 2.2), 4-week-old pigs were immunized with the TWJ-E2 vaccine according to the manufacturer's instructions and then challenged with genotype 2 strains. A group vaccinated with the conventional C-strain vaccine was included for comparison. TWJ-E2 vaccinated pigs developed higher levels of E2 and neutralizing antibodies than those receiving the commercial C-strain vaccine. All TWJ-E2 and C-strain vaccinated pigs survived challenge without development of fever, clinical signs or pathological lesions. In contrast, all unvaccinated control pigs displayed severe CSF disease with 40-100% mortalities by 24 days post challenge. None of the TWJ-E2 and C-strain vaccinated pigs developed viremia, viral shedding from tonsils, Erns protein in the sera, or viral RNA loads in different tissues after challenge, all of which were detected in the challenged unvaccinated controls. We conclude that vaccination of young pigs with TWJ-E2 provides complete immune protection against genotypically heterologous CSFVs and prevents viral shedding after challenge, with an efficacy at least comparable to that elicited by the conventional C-strain vaccine.
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Affiliation(s)
- Wenjie Gong
- Key Laboratory of Zoonoses Research, Ministry of Education, Zoonoses Institute, College of Veterinary Medicine, Jilin University, Changchun 130062, PR China; Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun 130122, PR China
| | - Junhui Li
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Zunbao Wang
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Jiumeng Sun
- Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun 130122, PR China
| | - Shijiang Mi
- Key Laboratory of Zoonoses Research, Ministry of Education, Zoonoses Institute, College of Veterinary Medicine, Jilin University, Changchun 130062, PR China; Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun 130122, PR China
| | - Jialun Xu
- Key Laboratory of Zoonoses Research, Ministry of Education, Zoonoses Institute, College of Veterinary Medicine, Jilin University, Changchun 130062, PR China; Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun 130122, PR China
| | - Jian Cao
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Yuzhen Hou
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Danyang Wang
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Xinliang Huo
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Yanjun Sun
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Pengjiang Wang
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Ke Yuan
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Yangyi Gao
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Xubin Zhou
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China
| | - Sun He
- Tecon Biology Joint Stock Company Limited, Urumqi 830013, PR China.
| | - Changchun Tu
- Key Laboratory of Zoonoses Research, Ministry of Education, Zoonoses Institute, College of Veterinary Medicine, Jilin University, Changchun 130062, PR China; Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun 130122, PR China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou University, Yangzhou 225009, PR China.
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18
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Coronado L, Rios L, Frías MT, Amarán L, Naranjo P, Percedo MI, Perera CL, Prieto F, Fonseca-Rodriguez O, Perez LJ. Positive selection pressure on E2 protein of classical swine fever virus drives variations in virulence, pathogenesis and antigenicity: Implication for epidemiological surveillance in endemic areas. Transbound Emerg Dis 2019; 66:2362-2382. [PMID: 31306567 DOI: 10.1111/tbed.13293] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 06/08/2019] [Accepted: 07/07/2019] [Indexed: 12/14/2022]
Abstract
Classical swine fever (CSF), caused by CSF virus (CSFV), is considered one of the most important infectious diseases with devasting consequences for the pig industry. Recent reports describe the emergence of new CSFV strains resulting from the action of positive selection pressure, due mainly to the bottleneck effect generated by ineffective vaccination. Even though a decrease in the genetic diversity of the positively selected CSFV strains has been observed by several research groups, there is little information about the effect of this selective force on the virulence degree, antigenicity and pathogenicity of this type of strains. Hence, the aim of the current study was to determine the effect of the positive selection pressure on these three parameters of CSFV strains, emerged as result of the bottleneck effects induced by improper vaccination in a CSF-endemic area. Moreover, the effect of the positively selected strains on the epidemiological surveillance system was assessed. By the combination of in vitro, in vivo and immunoinformatic approaches, we revealed that the action of the positive selection pressure induces a decrease in virulence and alteration in pathogenicity and antigenicity. However, we also noted that the evolutionary process of CSFV, especially in segregated microenvironments, could contribute to the gain-fitness event, restoring the highly virulent pattern of the circulating strains. Besides, we denoted that the presence of low virulent strains selected by bottleneck effect after inefficient vaccination can lead to a relevant challenge for the epidemiological surveillance of CSF, contributing to under-reports of the disease, favouring the perpetuation of the virus in the field. In this study, B-cell and CTL epitopes on the E2 3D-structure model were also identified. Thus, the current study provides novel and significant insights into variation in virulence, pathogenesis and antigenicity experienced by CSFV strains after the positive selection pressure effect.
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Affiliation(s)
- Liani Coronado
- Centro Nacional de Sanidad Agropecuaria (CENSA), OIE Collaborating Centre for Diagnosis and Risk Analysis of the Caribbean Region, La Habana, Cuba
| | - Liliam Rios
- Reiman Cancer Research Laboratory, Faculty of Medicine, University of New Brunswick, Saint John, New Brunswick, Canada
| | - María Teresa Frías
- Centro Nacional de Sanidad Agropecuaria (CENSA), OIE Collaborating Centre for Diagnosis and Risk Analysis of the Caribbean Region, La Habana, Cuba
| | - Laymara Amarán
- National Laboratory for Veterinary Diagnostic (NLVD), La Habana, Cuba
| | | | - María Irian Percedo
- Centro Nacional de Sanidad Agropecuaria (CENSA), OIE Collaborating Centre for Diagnosis and Risk Analysis of the Caribbean Region, La Habana, Cuba
| | - Carmen Laura Perera
- Centro Nacional de Sanidad Agropecuaria (CENSA), OIE Collaborating Centre for Diagnosis and Risk Analysis of the Caribbean Region, La Habana, Cuba
| | - Felix Prieto
- National Laboratory for Veterinary Diagnostic (NLVD), La Habana, Cuba
| | | | - Lester J Perez
- Department of Clinical Veterinary Medicine, College of Veterinary Science, University of Illinois, Urbana, IL, USA.,College of Veterinary Science, Veterinary Diagnostic Laboratory (VDL), University of Illinois, Urbana, IL, USA
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19
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Jalali SAH, Mohammadinezhad R, Mohammadi A, Latifian MH, Talebi M, Soleimanin-Zad S, Golkar P, Hemmatzadeh F. Molecular evolution and selection pressure analysis of infectious hematopoietic necrosis virus (IHNV) revealed the origin and phylogenetic relationship of Iranian isolates in recent epidemics in Iran. Virology 2019; 535:45-58. [PMID: 31272011 DOI: 10.1016/j.virol.2019.06.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 06/19/2019] [Accepted: 06/19/2019] [Indexed: 12/15/2022]
Abstract
Infectious hematopoietic necrosis virus (IHNV) is the causative agent for a lethal salmonid disease. In this study, we surveyed the IHNV's epidemiology, diversity and the origin of infection in Iran. Phylogenetic analysis revealed that Iranian isolates belonged to one of the two lineages of E genogroup. Subsequently, a combination of phylogenetic, antigenic and structural analysis was performed to investigate the evolution of E genogroup lineages. Site-specific analysis of the viral glycoprotein showed different co-evolving and positively selected sites in each lineage. Most of these sites were mapped to the predicted antigenic patches of the glycoprotein. Further characterization revealed E lineages can be differentiated, in part, by specific mutations at positions 91 and 130, which are located in the structurally flexible regions of the glycoprotein, suggesting a key adaptative role for these sites. These data may assist in better monitoring the emerging isolates in regions infected to IHNV from E genogroup.
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Affiliation(s)
- Seyed Amir Hossein Jalali
- Research Institute for Biotechnology and Bioengineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran; Department of Natural Resources, Isfahan University of Technology, Isfahan, 84156-83111, Iran.
| | - Rezvan Mohammadinezhad
- Research Institute for Biotechnology and Bioengineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Ashraf Mohammadi
- Human Viral vaccine Department, Razi Vaccine and Serum Research Institute (RVSRI), Hessark Karadj Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
| | - Mohamad Hassan Latifian
- Department of Agricultural Biotechnology, College of Agriculture, Isfahan University of Technology, Isfahan, 8415683111, Iran
| | - Majid Talebi
- Research Institute for Biotechnology and Bioengineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran; Department of Agricultural Biotechnology, College of Agriculture, Isfahan University of Technology, Isfahan, 8415683111, Iran
| | - Sabihe Soleimanin-Zad
- Research Institute for Biotechnology and Bioengineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran; Department of Food Science and Technology, College of Agriculture, Isfahan University of Technology, Isfahan, Iran
| | - Pouran Golkar
- Research Institute for Biotechnology and Bioengineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Farhid Hemmatzadeh
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, SA, Australia
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20
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Postel A, Nishi T, Kameyama KI, Meyer D, Suckstorff O, Fukai K, Becher P. Reemergence of Classical Swine Fever, Japan, 2018. Emerg Infect Dis 2019; 25:1228-1231. [PMID: 30870139 PMCID: PMC6537743 DOI: 10.3201/eid2506.181578] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In September 2018, classical swine fever reemerged in Japan after 26 years, affecting domestic pigs and wild boars. The causative virus belongs to the 2.1 subgenotype, which caused repeated outbreaks in eastern and Southeast Asia. Intensive surveillance of swine and vaccination of wild boars will help control and eradicate this disease in Japan.
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21
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Zhou B. Classical Swine Fever in China-An Update Minireview. Front Vet Sci 2019; 6:187. [PMID: 31249837 PMCID: PMC6584753 DOI: 10.3389/fvets.2019.00187] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 05/28/2019] [Indexed: 11/17/2022] Open
Abstract
Classical swine fever (CSF) remains one of the most economically important viral diseases of domestic pigs and wild boar worldwide. The causative agent is CSF virus, it is highly contagious, with high morbidity and mortality rates; as such, it is an OIE-listed disease. Owing to a nationwide policy of vaccinations of pigs, CSF is well-controlled in China, with large-scale outbreaks rarely seen. Sporadic outbreaks are however still reported every year. In order to cope with future crises and to eradicate CSF, China should strengthen and support biosecurity measures such as the timely reporting of suspected disease, technologies for reliable diagnoses, culling infected herds, and tracing possible contacts, as well as continued vaccination and support of research into drug and genetic therapies. This mini-review summarizes the epidemiology of and control strategies for CSF in China.
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Affiliation(s)
- Bin Zhou
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
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22
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Gong W, Li J, Wang Z, Sun J, Mi S, Lu Z, Cao J, Dou Z, Sun Y, Wang P, Yuan K, Zhang L, Zhou X, He S, Tu C. Virulence evaluation of classical swine fever virus subgenotype 2.1 and 2.2 isolates circulating in China. Vet Microbiol 2019; 232:114-120. [PMID: 31030834 DOI: 10.1016/j.vetmic.2019.04.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 03/31/2019] [Accepted: 04/02/2019] [Indexed: 01/01/2023]
Abstract
Classical swine fever (CSF) remains an important pig disease in China, where it usually presents with mild or atypical clinical manifestations, with large scale outbreaks rarely seen. This has led to speculation about the possible circulation of viral strains of low virulence. To investigate this possibility, five field isolates within the predominant genotype 2 (2.1b, 2.1c, 2.1 h and 2.2) were evaluated and compared by experimental infection of naturally farrowed but colostrum-deprived piglets. All infected piglets displayed clinical signs, including persistent high fever, depression, anorexia, dyspnea, conjunctivitis, constipation, and hesitant gait. Typical pathological lesions, including pulmonary edema, hemorrhagic or cellulosic exudation, and swelling and hemorrhage of lymph nodes, were observed. Viremia and Erns protein expression in the blood of all infected animals were detectable from 3 to 5 days post infection (DPI), their presence correlating with the onset of fever, clinical signs and leukopenia. E2 antibody did not develop in any of the field CSFV-infected piglets during the disease course, while Erns antibody was detectable in 4-56% of infected animals at various time points. Mortalities ranged from 20 to 80% within 21 DPI, progressing to 100% by 43 DPI. Based on clinical scores and fatalities within 21 DPI, 2 of the 5 field isolates were classified as of moderate virulence and 3 of high virulence; i.e., no field isolates of low virulence were identified. The study has provided data supporting the use of these isolates as challenge viruses to evaluate the efficacy of current CSF vaccines.
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Affiliation(s)
- Wenjie Gong
- Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun, PR China
| | - Junhui Li
- Tecon Biology Joint Stock Company Limited, Urumqi, PR China
| | - Zunbao Wang
- Tecon Biology Joint Stock Company Limited, Urumqi, PR China
| | - Jiumeng Sun
- Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun, PR China
| | - Shijiang Mi
- Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun, PR China
| | - Zongji Lu
- College of Life Sciences and Engineering, Foshan University, Foshan, PR China
| | - Jian Cao
- Tecon Biology Joint Stock Company Limited, Urumqi, PR China
| | - Zhihua Dou
- Tecon Biology Joint Stock Company Limited, Urumqi, PR China
| | - Yanjun Sun
- Tecon Biology Joint Stock Company Limited, Urumqi, PR China
| | - Pengjiang Wang
- Tecon Biology Joint Stock Company Limited, Urumqi, PR China
| | - Ke Yuan
- Tecon Biology Joint Stock Company Limited, Urumqi, PR China
| | - Liying Zhang
- College of Animal Sciences, Jilin University, Changchun, PR China
| | - Xubin Zhou
- Tecon Biology Joint Stock Company Limited, Urumqi, PR China
| | - Sun He
- Tecon Biology Joint Stock Company Limited, Urumqi, PR China.
| | - Changchun Tu
- Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun, PR China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, 225009, PR China.
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23
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Zhang H, Leng C, Tian Z, Liu C, Chen J, Bai Y, Li Z, Xiang L, Zhai H, Wang Q, Peng J, An T, Kan Y, Yao L, Yang X, Cai X, Tong G. Complete genomic characteristics and pathogenic analysis of the newly emerged classical swine fever virus in China. BMC Vet Res 2018; 14:204. [PMID: 29940930 PMCID: PMC6019732 DOI: 10.1186/s12917-018-1504-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 05/29/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Classical swine fever (CSF) is one of the most devastating and highly contagious viral diseases in the world. Since late 2014, outbreaks of a new sub-genotype 2.1d CSF virus (CSFV) had caused substantial economic losses in numbers of C-strain vaccinated swine farms in China. The objective of the present study was to explore the genomic characteristics and pathogenicity of the newly emerged CSFV isolates in China during 2014-2015. RESULTS All the new 8 CSFV isolates belonged to genetic sub-genotype 2.1d. Some genomic variations or deletions were found in the UTRs and E2 of these new isolates. In addition, the pathogenicity of HLJ1 was less than Shimen, suggesting the HLJ1 of sub-genotype 2.1d may be a moderated pathogenic isolate and the C-strain vaccine can supply complete protection. CONCLUSIONS The new CSFV isolates with unique genomic characteristics and moderate pathogenicity can be epidemic in many large-scale C-strain vaccinated swine farms. This study provides the information should be merited special attention on establishing prevention and control policies for CSF.
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Affiliation(s)
- Hongliang Zhang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Chaoliang Leng
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang, 473061 China
| | - Zhijun Tian
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Chunxiao Liu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Jiazeng Chen
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Yun Bai
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Zhen Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Lirun Xiang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Hongyue Zhai
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang, 473061 China
| | - Qian Wang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Jinmei Peng
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Tongqing An
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Yunchao Kan
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang, 473061 China
| | - Lunguang Yao
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang, 473061 China
| | - Xufu Yang
- North Guangdong Collaborative Innovation and Development Center of Pig Farming and Disease Control, Shaoguan University, Shaoguan, 512005 China
| | - Xuehui Cai
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001 China
| | - Guangzhi Tong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 518, Ziyue Road, Minhang District, Shanghai, 200241 China
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24
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Yoo SJ, Kwon T, Kang K, Kim H, Kang SC, Richt JA, Lyoo YS. Genetic evolution of classical swine fever virus under immune environments conditioned by genotype 1-based modified live virus vaccine. Transbound Emerg Dis 2018; 65:735-745. [PMID: 29319233 DOI: 10.1111/tbed.12798] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Indexed: 12/26/2022]
Abstract
Modified live vaccines (MLVs) based on genotype 1 strains, particularly C-strain, have been used to prevent and control classical swine fever virus (CSFV) worldwide. Nevertheless, a shift in the predominant CSFV strains circulating in the field from genotype 1 or 3 to genotype 2 is seen. Genotype 2 is genetically distant from the vaccine strains and was recently reported during outbreaks after vaccine failure; this has raised concerns that vaccination has influenced viral evolution. In Korea in 2016, there was an unexpected CSF outbreak in a MLV-vaccinated commercial pig herd. The causative CSFV strain was genetically distinct from previously isolated Korean strains but similar to recent Chinese strains exhibiting enhanced capacity to escape neutralization; this suggests the need for global cooperative research on the evolution of CSFV. We analysed global E2 sequences, using bioinformatics tools, revealing the evolutionary pathways of CSFV. Classical swine fever virus genotypes 1 and 2 experienced different degrees and patterns of evolutionary growth. Whereas genotype 1 stayed relatively conserved over time, the genetic diversity of genotype 2 has progressively expanded, with few fluctuations. It was determined that genotype 2 evolved under lower immune pressures and at a higher evolutionary rate than genotype 1. Further, several selected codons, under diversifying selection in genotype 1 but under purifying selection in genotype 2, correspond to antigenic determinants, which could lead to evasion of vaccine-induced immunity. Our findings provide evidence that evolutionary changes in CSFV are the result of the disproportionate usage of the CSF MLVs in endemic areas; this underscores the need to develop mitigation strategies to minimize the substantial risk associated with the emergence of vaccine-escaping mutants.
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Affiliation(s)
- S J Yoo
- College of Veterinary Medicine, Konkuk University, Gwangjin-gu, Seoul, South Korea
| | - T Kwon
- College of Veterinary Medicine, Konkuk University, Gwangjin-gu, Seoul, South Korea
| | - K Kang
- Sooje Animal Hospital, Dongducheon-si, Gyeonggi-do, Korea
| | - H Kim
- Optipharm Inc., Cheongju-si, Chungcheongbuk-do, Korea
| | - S C Kang
- Optipharm Inc., Cheongju-si, Chungcheongbuk-do, Korea
| | - J A Richt
- Department of Diagnostic Medicine/Pathobiology, Center of Excellence for Emerging and Zoonotic Animal Diseases, Kansas State University, Manhattan, KS, USA
| | - Y S Lyoo
- College of Veterinary Medicine, Konkuk University, Gwangjin-gu, Seoul, South Korea
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25
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Rios L, Coronado L, Naranjo-Feliciano D, Martínez-Pérez O, Perera CL, Hernandez-Alvarez L, Díaz de Arce H, Núñez JI, Ganges L, Pérez LJ. Deciphering the emergence, genetic diversity and evolution of classical swine fever virus. Sci Rep 2017; 7:17887. [PMID: 29263428 PMCID: PMC5738429 DOI: 10.1038/s41598-017-18196-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 12/01/2017] [Indexed: 12/15/2022] Open
Abstract
Classical swine fever (CSF) is one of the most important infectious diseases causing significant economic losses. Its causal agent, CSF virus (CSFV), is a member of the Pestivirus genus included into the Flaviviridae family. Previous molecular epidemiology studies have revealed the CSFV diversity is divided into three main genotypes and different subgenotypes. However, the classification system for CSFV has not yet been harmonized internationally. Similarly, the phylogeny and evolutionary dynamics of CSFV remain unclear. The current study provides novel and significant insights into the origin, diversification and evolutionary process of CSFV. In addition, the best phylogenetic marker for CSFV capable of reproducing the same phylogenetic and evolutionary information as the complete viral genome is characterized. Also, a reliable cut-off to accurately classify CSFV at genotype and subgenotype levels is established. Based on the time for the most recent common ancestor (tMRCA) reconstruction and cophylogenetic analysis, it was determined that CSFV emerged around 225 years ago when the Tunisian Sheep Virus jumped from its natural host to swine. CSFV emergence was followed by a genetic expansion in three main lineages, driven by the action of positive selection pressure and functional divergence, as main natural forces.
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Affiliation(s)
- Liliam Rios
- University of New Brunswick, Saint John, New Brunswick, E2L4L5, Canada
| | - Liani Coronado
- Centro Nacional de Sanidad Agropecuaria (CENSA), La Habana, 32700, Cuba
| | | | | | - Carmen L Perera
- Centro Nacional de Sanidad Agropecuaria (CENSA), La Habana, 32700, Cuba
| | | | - Heidy Díaz de Arce
- Hospital Italiano de Buenos Aires, Juan D. Perón 4190, C1181ACH, Buenos Aires, Argentina
| | - José I Núñez
- IRTA-CReSA. Centre de Recerca en Sanitat Animal, Barcelona, 08193, Spain
| | - Llilianne Ganges
- IRTA-CReSA. Centre de Recerca en Sanitat Animal, Barcelona, 08193, Spain.,OIE Reference Laboratory for Classical Swine Fever and OIE Collaborative Centre for Research and Control of Emerging and Re-emerging Swine Diseases in Europe, IRTA-CReSA, Barcelona, Spain
| | - Lester J Pérez
- Dalhousie University, Dalhousie Medicine New Brunswick, Saint John, New Brunswick, E2L4L5, Canada.
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26
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Lin J, Wang C, Zhang L, Wang T, Zhang J, Liang W, Li C, Qian G, Ouyang Y, Guo K, Zhang Y. Rab5 Enhances Classical Swine Fever Virus Proliferation and Interacts with Viral NS4B Protein to Facilitate Formation of NS4B Related Complex. Front Microbiol 2017; 8:1468. [PMID: 28848503 PMCID: PMC5550665 DOI: 10.3389/fmicb.2017.01468] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 07/20/2017] [Indexed: 11/13/2022] Open
Abstract
Classical swine fever virus (CSFV) is a fatal pig pestivirus and causes serious financial losses to the pig industry. CSFV NS4B protein is one of the most important viral replicase proteins. Rab5, a member of the small Rab GTPase family, is involved in infection and replication of numerous viruses including hepatitis C virus and dengue virus. Until now, the effects of Rab5 on the proliferation of CSFV are poorly defined. In the present study, we showed that Rab5 could enhance CSFV proliferation by utilizing lentivirus-mediated constitutive overexpression and eukaryotic plasmid transient overexpression approaches. On the other hand, lentivirus-mediated short hairpin RNA knockdown of Rab5 dramatically inhibited virus production. Co-immunoprecipitation, glutathione S-transferase pulldown and laser confocal microscopy assays further confirmed the interaction between Rab5 and CSFV NS4B protein. In addition, intracellular distribution of NS4B-Red presented many granular fluorescent signals (GFS) in CSFV infected PK-15 cells. Inhibition of basal Rab5 function with Rab5 dominant negative mutant Rab5S34N resulted in disruption of the GFS. These results indicate that Rab5 plays a critical role in facilitating the formation of the NS4B related complexes. Furthermore, it was observed that NS4B co-localized with viral NS3 and NS5A proteins in the cytoplasm, suggesting that NS3 and NS5A might be components of the NS4B related complex. Taken together, these results demonstrate that Rab5 positively modulates CSFV propagation and interacts with NS4B protein to facilitate the NS4B related complexes formation.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Yanming Zhang
- College of Veterinary Medicine, Northwest A&F UniversityYangling, China
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27
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Leng C, Zhang H, Kan Y, Yao L, Li M, Zhai H, Li Z, Liu C, Shi H, Ji J, Qiu R, Tian Z. Characterisation of Newly Emerged Isolates of Classical Swine Fever Virus in China, 2014-2015. J Vet Res 2017; 61:1-9. [PMID: 29978049 PMCID: PMC5894411 DOI: 10.1515/jvetres-2017-0001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 03/09/2017] [Indexed: 11/22/2022] Open
Abstract
Introduction In 2014–2015, the epidemic of classical swine fever (CSF) occurred in many large-scale pig farms in different provinces of China, and a subgenotype 2.1d of CSF virus (CSFV) was newly identified. Material and Methods The phylogenetic relationship, genetic diversity, and epidemic status of the 2014–2015 CSFV isolates, 18 new CSFV isolates collected in 2015, and 43 other strains isolated in 2014–2015 were fully analysed, together with 163 CSFV reference isolates. Results Fifty-two 2014–2015 isolates belonged to subgenotype 2.1d and nine other isolates belonged to subgenotype 2.1b. The two subgenotype isolates showed unique molecular characteristics. Furthermore, the 2.1d isolates were found to possibly diverge from 2.1b isolates. Conclusion This study suggests that the Chinese CSFVs will remain pandemic.
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Affiliation(s)
- Chaoliang Leng
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang 473061, China
| | - Hongliang Zhang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Yunchao Kan
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang 473061, China
| | - Lunguang Yao
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang 473061, China
| | - Mingliang Li
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang 473061, China
| | - Hongyue Zhai
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang 473061, China
| | - Zhen Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Chunxiao Liu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Hongfei Shi
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang 473061, China
| | - Jun Ji
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang 473061, China
| | - Reng Qiu
- Henan Key Laboratory of Insect Biology in Funiu Mountain, Henan Provincial Engineering Laboratory of Insects Bio-reactor, China-UK-NYNU-RRes Joint Laboratory of Insect Biology, Nanyang Normal University, Nanyang 473061, China
| | - Zhijun Tian
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
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28
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Luo Y, Ji S, Lei JL, Xiang GT, Liu Y, Gao Y, Meng XY, Zheng G, Zhang EY, Wang Y, Du ML, Li Y, Li S, He XJ, Sun Y, Qiu HJ. Efficacy evaluation of the C-strain-based vaccines against the subgenotype 2.1d classical swine fever virus emerging in China. Vet Microbiol 2017; 201:154-161. [PMID: 28284603 DOI: 10.1016/j.vetmic.2017.01.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 01/11/2017] [Accepted: 01/12/2017] [Indexed: 10/20/2022]
Abstract
Classical swine fever (CSF) is a devastating infectious disease of pigs caused by classical swine fever virus (CSFV). The disease has been controlled following extensive vaccination with the lapinized attenuated vaccine C-strain for decades in China. However, frequent CSF outbreaks occurred recently in a large number of C-strain-vaccinated pig farms in China and a new subgenotype 2.1d of CSFV has been reported to be responsible for the outbreaks. Here we analyzed the molecular variations and antigenic differences among the C-strain-based commercial vaccines of different origins from different manufacturers in China, and reevaluated the vaccines against the emerging subgenotype 2.1d strain of CSFV. The results showed that the C-strain adapted to the continuous ST cell line (CST) contain a unique M290K variation on the E2 protein, compared to those of primary BT cells (CBT) or rabbit origin (CRT) and the traditional C-strain sequences available in the GenBank database. Serum neutralization test revealed the antigenic differences between CST and CBT or CRT. Notably, the neutralizing titers of porcine anti-C-strain sera against the CSFV isolate of subgenotype 2.1d were significantly lower than those against C-strain or Shimen strain. The C-strain-vaccinated, subgenotype 2.1d HLJZZ2014 strain-challenged pigs did not show any clinical signs and all survived. However, these pigs displayed mild pathological and histological lesions, and the CSFV viral RNA was detected in the various tissue and blood samples. Taken together, the C-strain-based vaccines of different origins showed molecular variations and antigenic differences, and could provide clinical but not pathological and virological protection against the subgenotype 2.1d CSFV emerging in China. Further investigation is needed to comprehensively assess the efficacy of C-strain of different doses against the subgenotype 2.1d CSFV.
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Affiliation(s)
- Yuzi Luo
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Shengwei Ji
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Jian-Lin Lei
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Guang-Tao Xiang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Yan Liu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Yao Gao
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Xing-Yu Meng
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Guanglai Zheng
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - En-Yu Zhang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Yimin Wang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Ming-Liang Du
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Yongfeng Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Su Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China
| | - Xi-Jun He
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China.
| | - Yuan Sun
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China.
| | - Hua-Ji Qiu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 678 Haping Road, Harbin 150069, PR China.
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Coronado L, Liniger M, Muñoz-González S, Postel A, Pérez LJ, Pérez-Simó M, Perera CL, Frías-Lepoureau MT, Rosell R, Grundhoff A, Indenbirken D, Alawi M, Fischer N, Becher P, Ruggli N, Ganges L. Novel poly-uridine insertion in the 3'UTR and E2 amino acid substitutions in a low virulent classical swine fever virus. Vet Microbiol 2017; 201:103-112. [PMID: 28284595 DOI: 10.1016/j.vetmic.2017.01.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 01/10/2017] [Accepted: 01/12/2017] [Indexed: 12/24/2022]
Abstract
In this study, we compared the virulence in weaner pigs of the Pinar del Rio isolate and the virulent Margarita strain. The latter caused the Cuban classical swine fever (CSF) outbreak of 1993. Our results showed that the Pinar del Rio virus isolated during an endemic phase is clearly of low virulence. We analysed the complete nucleotide sequence of the Pinar del Rio virus isolated after persistence in newborn piglets, as well as the genome sequence of the inoculum. The consensus genome sequence of the Pinar del Rio virus remained completely unchanged after 28days of persistent infection in swine. More importantly, a unique poly-uridine tract was discovered in the 3'UTR of the Pinar del Rio virus, which was not found in the Margarita virus or any other known CSFV sequences. Based on RNA secondary structure prediction, the poly-uridine tract results in a long single-stranded intervening sequence (SS) between the stem-loops I and II of the 3'UTR, without major changes in the stem- loop structures when compared to the Margarita virus. The possible implications of this novel insertion on persistence and attenuation remain to be investigated. In addition, comparison of the amino acid sequence of the viral proteins Erns, E1, E2 and p7 of the Margarita and Pinar del Rio viruses showed that all non-conservative amino acid substitutions acquired by the Pinar del Rio isolate clustered in E2, with two of them being located within the B/C domain. Immunisation and cross-neutralisation experiments in pigs and rabbits suggest differences between these two viruses, which may be attributable to the amino acid differences observed in E2. Altogether, these data provide fresh insights into viral molecular features which might be associated with the attenuation and adaptation of CSFV for persistence in the field.
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Affiliation(s)
- Liani Coronado
- Centro Nacional de Sanidad Agropecuaria (CENSA), La Habana, Cuba; IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Matthias Liniger
- Institute of Virology and Immunology IVI, Mittelhäusern, Switzerland
| | - Sara Muñoz-González
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Alexander Postel
- EU and OIE Reference Laboratory for Classical Swine Fever, Institute of Virology, Department of Infectious Diseases, University of Veterinary Medicine, Hannover, Germany
| | | | - Marta Pérez-Simó
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | | | | | - Rosa Rosell
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain; Departamentd'Agricultura, Ramaderia, Pesca, Alimentació i Medi Natural, (DAAM), Generalitat de Catalunya, Spain
| | - Adam Grundhoff
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Research Group Virus Genomics, Hamburg, Germany
| | - Daniela Indenbirken
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Research Group Virus Genomics, Hamburg, Germany
| | - Malik Alawi
- Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Research Group Virus Genomics, Hamburg, Germany; Bioinformatics Service Facility, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Nicole Fischer
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Paul Becher
- EU and OIE Reference Laboratory for Classical Swine Fever, Institute of Virology, Department of Infectious Diseases, University of Veterinary Medicine, Hannover, Germany
| | - Nicolas Ruggli
- Institute of Virology and Immunology IVI, Mittelhäusern, Switzerland
| | - Llilianne Ganges
- IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
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30
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Liao X, Wang Z, Cao T, Tong C, Geng S, Gu Y, Zhou Y, Li X, Fang W. Hypervariable antigenic region 1 of classical swine fever virus E2 protein impacts antibody neutralization. Vaccine 2016; 34:3723-30. [PMID: 27317266 DOI: 10.1016/j.vaccine.2016.06.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Revised: 05/14/2016] [Accepted: 06/01/2016] [Indexed: 10/21/2022]
Abstract
Envelope glycoprotein E2 of classical swine fever virus (CSFV) is the major antigen that induces neutralizing antibodies and confers protection against CSFV infection. There are three hypervariable antigenic regions (HAR1, HAR2 and HAR3) of E2 that are different between the group 1 vaccine C-strain and group 2 clinical isolates. This study was aimed to characterize the antigenic epitope region recognized by monoclonal antibody 4F4 (mAb-4F4) that is present in the group 2 field isolate HZ1-08, but not in the C-strain, and examine its impact on neutralization titers when antisera from different recombinant viruses were cross-examined. Indirect ELISA with C-strain E2-based chimeric proteins carrying the three HAR regions showed that the mAb-4F4 bound to HAR1 from HZ1-08 E2, but not to HAR2 or HAR3, indicating that the specific epitope is located in the HAR1 region. Of the 6 major residues differences between C-strain and field isolates, Glu713 in the HAR1 region of strain HZ1-08 is critical for mAb-4F4 binding either at the recombinant protein level or using intact recombinant viruses carrying single mutations. C-strain-based recombinant viruses carrying the most antigenic part of E2 or HAR1 from strain HZ1-08 remained non-pathogenic to pigs and induced good antibody responses. By cross-neutralization assay, we observed that the anti-C-strain serum lost most of its neutralization capacity to RecC-HZ-E2 and QZ-14 (subgroup 2.1d field isolate in 2014), and vice versa. More importantly, the RecC-HAR1 virus remained competent in neutralizing ReC-HZ-E2 and QZ-14 strains without compromising the neutralization capability to the recombinant C-strain. Thus, we propose that chimeric C-strain carrying the HAR1 region of field isolates is a good vaccine candidate for classical swine fever.
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Affiliation(s)
- Xun Liao
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang 310058, PR China
| | - Zuohuan Wang
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang 310058, PR China
| | - Tong Cao
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang 310058, PR China
| | - Chao Tong
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang 310058, PR China
| | - Shichao Geng
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang 310058, PR China
| | - Yuanxing Gu
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang 310058, PR China
| | - Yingshan Zhou
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang 310058, PR China
| | - Xiaoliang Li
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang 310058, PR China
| | - Weihuan Fang
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Hangzhou, Zhejiang 310058, PR China.
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