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Zhao Y, Han L, Sang H, Liu S, Yang P, Hou Y, Xiao Y. Swine Influenza Viruses Isolated from 2019 to 2022 in Shandong Province, China, Exemplify the Dominant Genotype. Genes (Basel) 2024; 15:849. [PMID: 39062628 PMCID: PMC11275327 DOI: 10.3390/genes15070849] [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: 05/21/2024] [Revised: 06/22/2024] [Accepted: 06/24/2024] [Indexed: 07/28/2024] Open
Abstract
Swine influenza viruses (SIVs) have been circulating in swine globally and are potential threats to human health. During the surveillance of SIVs in Shandong Province, China, from 2019 to 2022, 21 reassortant G4 genotype Eurasian avian-like (EA) H1N1 subtypes containing genes from the EA H1N1 (HA and NA), 2009 pandemic (pdm/09) H1N1 virus (PB2, PB1, PA, NP, and M), and classical swine (CS) H1N1 (NS) lineages were isolated. The analysis of the key functional amino acid sites in the isolated viruses showed that two mutation sites (190D and 225E) that preferentially bind to the human α2-6 sialic acid receptor were found in HA. In PB2, three mutation sites (271A, 590S, and 591R) that may increase mammalian fitness and a mutation site (431M) that increases pathogenicity in mice were found. A typical human signature marker that may promote infection in humans, 357K, was found in NP. The viruses could replicate efficiently in mouse lungs and turbinates, and one of the H1N1 isolates could replicate in mouse kidneys and brains without prior adaption, which indicates that the viruses potentially pose a threat to human health. Histopathological results showed that the isolated viruses caused typical bronchopneumonia and encephalitis in mice. The results indicate that G4 genotype H1N1 has potential transmissibility to humans, and surveillance should be enhanced, which could provide important information for assessing the pandemic potential of the viruses.
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Affiliation(s)
| | | | | | | | | | | | - Yihong Xiao
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, 61 Daizong Street, Tai’an 271018, China; (Y.Z.); (L.H.); (H.S.); (S.L.); (P.Y.); (Y.H.)
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Wang XH, Gong XQ, Wen F, Ruan BY, Yu LX, Liu XM, Wang Q, Wang SY, Wang J, Zhang YF, Zhou YJ, Shan TL, Tong W, Zheng H, Kong N, Yu H, Tong GZ. The role of PA-X C-terminal 20 residues of classical swine influenza virus in its replication and pathogenicity. Vet Microbiol 2020; 251:108916. [PMID: 33197868 DOI: 10.1016/j.vetmic.2020.108916] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 10/28/2020] [Indexed: 12/15/2022]
Abstract
PA-X is a fusion protein encoded by a +1 frameshifted open reading frame (X-ORF) in PA gene. The X-ORF can be translated in full-length (61 amino acids, aa) or truncated (41 aa) form. However, the role of C-Terminal 20 aa of PA-X in virus function has not yet been fully elucidated. To this end, we constructed the contemporary influenza viruses with full and truncated PA-X by reverse genetics to compare their replication and pathogenicity. The full-length PA-X virus in MDCK and human A549 cells conferred 10- to 100-fold increase in viral replication, and more virulent and caused more severe inflammatory responses in mice relative to corresponding truncated PA-X virus, suggesting that the terminal 20 aa could play a role in enhancing viral replication and contribute to virulence.
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Affiliation(s)
- Xiu-Hui Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Hebei University of Engineering, Handan 056038, China
| | - Xiao-Qian Gong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Feng Wen
- College of Life Science and Engineering, Foshan University, Foshan 528231, China
| | - Bao-Yang Ruan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Ling-Xue Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Xiao-Min Liu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Qi Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Shuai-Yong Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Juan Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Yi-Feng Zhang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Hebei University of Engineering, Handan 056038, China
| | - Yan-Jun Zhou
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Tong-Ling Shan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Wu Tong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Hao Zheng
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Ning Kong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Hai Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai 200240, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China.
| | - Guang-Zhi Tong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
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Ruan BY, Yao Y, Wang SY, Gong XQ, Liu XM, Wang Q, Yu LX, Zhu SQ, Wang J, Shan TL, Zhou YJ, Tong W, Zheng H, Li GX, Gao F, Kong N, Yu H, Tong GZ. Protective efficacy of a bivalent inactivated reassortant H1N1 influenza virus vaccine against European avian-like and classical swine influenza H1N1 viruses in mice. Vet Microbiol 2020; 246:108724. [PMID: 32605742 DOI: 10.1016/j.vetmic.2020.108724] [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: 03/11/2020] [Revised: 05/06/2020] [Accepted: 05/09/2020] [Indexed: 11/29/2022]
Abstract
The classical swine (CS) H1N1 swine influenza virus (SIVs) emerged in humans as a reassortant virus that caused the H1N1 influenza virus pandemic in 2009, and the European avian-like (EA) H1N1 SIVs has caused several human infections in European and Asian countries. Development of the influenza vaccines that could provide effective protective efficacy against SIVs remains a challenge. In this study, the bivalent reassortant inactivated vaccine comprised of SH1/PR8 and G11/PR8 arboring the hemagglutinin (HA) and neuraminidase (NA) genes from prevalent CS and EA H1N1 SIVs and six internal genes from the A/Puerto Rico/8/34(PR8) virus was developed. The protective efficacy of this bivalent vaccine was evaluated in mice challenged with the lethal doses of CS and EA H1N1 SIVs. The result showed that univalent inactivated vaccine elicited high-level antibody against homologous H1N1 viruses while cross-reactive antibody responses to heterologous H1N1 viruses were not fully effective. In a mouse model, the bivalent inactivated vaccine conferred complete protection against lethal challenge doses of EA SH1 virus or CS G11 virus, whereas the univalent inactivated vaccine only produced insufficient protection against heterologous SIVs. In conclusion, our data demonstrated that the reassortant bivalent inactivated vaccine comprised of SH1/PR8 and G11/PR8 could provide effective protection against the prevalent EA and CS H1N1 subtype SIVs in mice.
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Affiliation(s)
- Bao-Yang Ruan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Yun Yao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Shuai-Yong Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Xiao-Qian Gong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Xiao-Min Liu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Qi Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Ling-Xue Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Shi-Qiang Zhu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Juan Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Tong-Ling Shan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Yan-Jun Zhou
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Wu Tong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Hao Zheng
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Guo-Xin Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Fei Gao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Ning Kong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai 200240, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Hai Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai 200240, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China.
| | - Guang-Zhi Tong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
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Dendritic Cells Targeting Lactobacillus plantarum Strain NC8 with a Surface-Displayed Single-Chain Variable Fragment of CD11c Induce an Antigen-Specific Protective Cellular Immune Response. Infect Immun 2020; 88:IAI.00759-19. [PMID: 31740528 DOI: 10.1128/iai.00759-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 11/08/2019] [Indexed: 12/16/2022] Open
Abstract
Influenza A virus (H1N1) is an acute, highly contagious respiratory virus. The use of lactic acid bacteria (LAB) to deliver mucosal vaccines against influenza virus infection is a research hot spot. In this study, two recombinant Lactobacillus plantarum strains expressing hemagglutinin (HA) alone or coexpressing aCD11c-HA to target HA protein to dendritic cells (DCs) by fusion to an anti-CD11c single-chain antibody (aCD11c) were constructed. The activation of bone marrow dendritic cells (BMDCs) by recombinant strains and the interaction of activated BMDCs and sorted CD4+ or CD8+ T cells were evaluated through flow cytometry in vitro, and cellular supernatants were assessed by using an enzyme-linked immunosorbent assay kit. The results demonstrated that, compared to the HA strain, the aCD11c-HA strain significantly increased the activation of BMDCs and increased the production of CD4+ gamma interferon-positive (IFN-γ+) T cells, CD8+ IFN-γ+ T cells, and IFN-γ in the cell culture supernatant in vitro Consistent with these results, the aCD11c-HA strain clearly increased the activation and maturation of DCs, the HA-specific responses of CD4+ IFN-γ+ T cells, CD8+ IFN-γ+ T cells, and CD8+ CD107a+ T cells, and the proliferation of T cells in the spleen, finally increasing the levels of specific antibodies and neutralizing antibodies in mice. In addition, the protection of immunized mice was observed after viral infection, as evidenced by improved weight loss, survival, and lung pathology. The adoptive transfer of CD8+ T cells from the aCD11c-HA mice to NOD/Lt-SCID mice resulted in a certain level of protection after influenza virus infection, highlighting the efficacy of the aCD11c targeting strategy.
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Ruan BY, Wen F, Gong XQ, Liu XM, Wang Q, Yu LX, Wang SY, Zhang P, Yang HM, Shan TL, Zheng H, Zhou YJ, Tong W, Gao F, Tong GZ, Yu H. Protective efficacy of a high-growth reassortant H1N1 influenza virus vaccine against the European Avian-like H1N1 swine influenza virus in mice and pigs. Vet Microbiol 2018; 222:75-84. [PMID: 30080677 DOI: 10.1016/j.vetmic.2018.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 07/04/2018] [Accepted: 07/05/2018] [Indexed: 11/30/2022]
Abstract
Swine influenza A viruses (SIVs) causing outbreaks of acute, highly contagious respiratory disease in pigs also pose a potential threat to public health. European avian-like H1N1 (EA H1N1) SIVs are the predominant circulating viruses in pigs in China and also occasionally cause human infection. In this study, a high-growth reassortant virus (SH1/PR8), with HA and NA genes from a representative EA H1N1 isolate A/Swine/Shanghai/1/2014 (SH1) in China and six internal genes from the high-growth A/Puerto Rico/8/34 (PR8) virus, was generated by plasmid-based reverse genetics and tested as a candidate seed virus for the preparation of inactivated vaccine. The protective efficacy of inactivated SH1/PR8 was evaluated in mice and pigs challenged with wild-type SH1 virus. After primer and boost vaccination, the SH1/PR8 vaccine induced high-level hemagglutination inhibiting (HI) antibodies, IgG antibodies, and neutralization antibodies in mice and pigs. Mice and pigs in the vaccinated group showed less clinical phenomena and pathological changes than those in the unvaccinated group. In conclusion, the inactivated high-growth reassortant vaccine SH1/PR8 could induce high antibody levels and complete protection is expected against SH1 wild type SIV, and protection against heterologous EA H1N1 SIV needs further evaluation.
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Affiliation(s)
- Bao-Yang Ruan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Feng Wen
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA
| | - Xiao-Qian Gong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Xiao-Min Liu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Qi Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Ling-Xue Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Shuai-Yong Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Peng Zhang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Hai-Ming Yang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Tong-Ling Shan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Hao Zheng
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Yan-Jun Zhou
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Wu Tong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Fei Gao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Guang-Zhi Tong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, PR China.
| | - Hai Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China; Shanghai Key Laboratory of Veterinary Biotechnology, Shanghai 200240, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, PR China.
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PA-X protein decreases replication and pathogenicity of swine influenza virus in cultured cells and mouse models. Vet Microbiol 2017. [PMID: 28622865 DOI: 10.1016/j.vetmic.2017.05.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Swine influenza viruses have been circulating in pigs throughout world and might be potential threats to human health. PA-X protein is a newly discovered protein produced from the PA gene by ribosomal frameshifting and the effects of PA-X on the 1918 H1N1, the pandemic 2009 H1N1, the highly pathogenic avian H5N1 and the avian H9N2 influenza viruses have been reported. However, the role of PA-X in the pathogenesis of swine influenza virus is still unknown. In this study, we rescued the H1N1 wild-type (WT) classical swine influenza virus (A/Swine/Guangdong/1/2011 (H1N1)) and H1N1 PA-X deficient virus containing mutations at the frameshift motif, and compared their replication properties and pathogenicity of swine influenza virus in vitro and in vivo. Our results show that the expression of PA-X inhibits virus replication and polymerase activity in cultured cells and decreases virulence in mouse models. Therefore, our study demonstrates that PA-X protein acts as a negative virulence regulator for classical H1N1 swine influenza virus and decreases virulence by inhibiting viral replication and polymerase activity, deepening our understanding of the pathogenesis of swine influenza virus.
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Wen F, Ma JH, Yu H, Yang FR, Huang M, Zhou YJ, Li ZJ, Wang XH, Li GX, Jiang YF, Tong W, Tong GZ. A novel M2e-multiple antigenic peptide providing heterologous protection in mice. J Vet Sci 2016; 17:71-8. [PMID: 27051342 PMCID: PMC4808646 DOI: 10.4142/jvs.2016.17.1.71] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 06/13/2015] [Accepted: 07/31/2015] [Indexed: 11/20/2022] Open
Abstract
Swine influenza viruses (SwIVs) cause considerable morbidity and mortality in domestic pigs, resulting in a significant economic burden. Moreover, pigs have been considered to be a possible mixing vessel in which novel strains loom. Here, we developed and evaluated a novel M2e-multiple antigenic peptide (M2e-MAP) as a supplemental antigen for inactivated H3N2 vaccine to provide cross-protection against two main subtypes of SwIVs, H1N1 and H3N2. The novel tetra-branched MAP was constructed by fusing four copies of M2e to one copy of foreign T helper cell epitopes. A high-yield reassortant H3N2 virus was generated by plasmid based reverse genetics. The efficacy of the novel H3N2 inactivated vaccines with or without M2e-MAP supplementation was evaluated in a mouse model. M2e-MAP conjugated vaccine induced strong antibody responses in mice. Complete protection against the heterologous swine H1N1 virus was observed in mice vaccinated with M2e-MAP combined vaccine. Moreover, this novel peptide confers protection against lethal challenge of A/Puerto Rico/8/34 (H1N1). Taken together, our results suggest the combined immunization of reassortant inactivated H3N2 vaccine and the novel M2e-MAP provided cross-protection against swine and human viruses and may serve as a promising approach for influenza vaccine development.
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Affiliation(s)
- Feng Wen
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Ji-Hong Ma
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Hai Yu
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Fu-Ru Yang
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Meng Huang
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Yan-Jun Zhou
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Ze-Jun Li
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Xiu-Hui Wang
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Guo-Xin Li
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Yi-Feng Jiang
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Wu Tong
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Guang-Zhi Tong
- Division of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
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