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Song Y, Yuan Z, Ji J, Ruan Y, Li X, Wang L, Zeng W, Wu K, Hu W, Yi L, Ding H, Zhao M, Fan S, Li Z, Chen J. Development of a Ferritin-Based Nanoparticle Vaccine against Classical Swine Fever. Vaccines (Basel) 2024; 12:948. [PMID: 39204071 PMCID: PMC11360710 DOI: 10.3390/vaccines12080948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2024] [Revised: 08/14/2024] [Accepted: 08/20/2024] [Indexed: 09/03/2024] Open
Abstract
The occurrence of classical swine fever (CSF) poses a significant threat to the global swine industry. Developing an effective and safe vaccine is crucial for preventing and controlling CSF. Here, we constructed self-assembled ferritin nanoparticles fused with the classical swine fever virus (CSFV) E2 protein and a derived B cell epitope (Fe-E2B) using a baculovirus expression system (BVES), demonstrating enhanced immunogenicity. Furthermore, we provide a detailed evaluation of the immunological efficacy of the FeE2B in rabbits. The results showed that robust and sustained antibody responses were detected in rabbits immunized with the Fe-E2B nanoparticle vaccine, comparable to those elicited by commercially available vaccines. Additionally, we demonstrated that the vaccine effectively activated crucial immune factors IFN-γ and IL-4 in vivo, increasing their levels by 1.41-fold and 1.39-fold, respectively. Immunization with Fe-E2B enabled rabbits to avoid viremia and stereotypic fever after CSFV challenge. In conclusion, this study highlights the potential of ferritin nanoparticles as antigen-presenting carriers to induce robust immune responses, proposing a candidate vaccine strategy for the prevention and control of CSF.
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Affiliation(s)
- Yiwan Song
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
- Key Laboratory of Zoonotic Disease Prevention and Control of Guangdong, South China Agricultural University, Guangzhou 510642, China
| | - Zhongmao Yuan
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
- Key Laboratory of Zoonotic Disease Prevention and Control of Guangdong, South China Agricultural University, Guangzhou 510642, China
| | - Junzhi Ji
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
- Key Laboratory of Zoonotic Disease Prevention and Control of Guangdong, South China Agricultural University, Guangzhou 510642, China
| | - Yang Ruan
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
| | - Xiaowen Li
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
| | - Lianxiang Wang
- Wen’s Group Academy, Wen’s Foodstuffs Group Co., Ltd., Xinxing 527400, China;
| | - Weijun Zeng
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
- Key Laboratory of Zoonotic Disease Prevention and Control of Guangdong, South China Agricultural University, Guangzhou 510642, China
| | - Keke Wu
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
- Key Laboratory of Zoonotic Disease Prevention and Control of Guangdong, South China Agricultural University, Guangzhou 510642, China
| | - Wenshuo Hu
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
| | - Lin Yi
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
- Key Laboratory of Zoonotic Disease Prevention and Control of Guangdong, South China Agricultural University, Guangzhou 510642, China
| | - Hongxing Ding
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
- Key Laboratory of Zoonotic Disease Prevention and Control of Guangdong, South China Agricultural University, Guangzhou 510642, China
| | - Mingqiu Zhao
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
| | - Shuangqi Fan
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
- Key Laboratory of Zoonotic Disease Prevention and Control of Guangdong, South China Agricultural University, Guangzhou 510642, China
| | - Zhaoyao Li
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
- Wen’s Group Academy, Wen’s Foodstuffs Group Co., Ltd., Xinxing 527400, China;
| | - Jinding Chen
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China; (Y.S.); (Z.Y.); (J.J.); (Y.R.); (X.L.); (W.Z.); (K.W.); (W.H.); (L.Y.); (H.D.); (M.Z.); (S.F.)
- Key Laboratory of Zoonotic Disease Prevention and Control of Guangdong, South China Agricultural University, Guangzhou 510642, China
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Mi S, Wang L, Li H, Bao F, Madera R, Shi X, Zhang L, Mao Y, Yan R, Xia X, Gong W, Shi J, Tu C. Characterization of monoclonal antibodies that specifically differentiate field isolates from vaccine strains of classical swine fever virus. Front Immunol 2022; 13:930631. [PMID: 35958565 PMCID: PMC9361847 DOI: 10.3389/fimmu.2022.930631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 06/27/2022] [Indexed: 11/13/2022] Open
Abstract
Classical swine fever virus (CSFV) is a major animal pathogen threatening the global pork industry. To date, numerous anti-CSFV monoclonal antibodies (mAbs) and their recognizing epitopes have been reported. However, few mAbs were systematically characterized for the capacity to differentiate field CSFV isolates from CSF vaccine strains, and the molecular basis associated with antigenic differences between vaccines and field isolates is still largely unknown. In the present study, recombinant CSFV structural glycoproteins E2 of both virulent and vaccine strains and Erns of vaccine strain were expressed using eukaryotic cells and murine mAbs generated against E2 and Erns. After serial screening and cloning of the hybridomas, the viral spectra of mAbs were respectively determined by indirect fluorescent antibody assay (IFA) using 108 CSFVs, followed by Western blot analysis using expressed glycoproteins of all CSFV sub-genotypes including vaccine strains. The antigenic structures recognized by these mAbs were characterized by epitope mapping using truncated, chimeric, and site-directed mutated E2 and Erns proteins. We have identified two vaccine-specific, one field isolate-specific, and two universal CSFV-specific mAbs and five novel conformational epitopes with critical amino acid (aa) motifs that are associated with these five mAbs: 213EPD215, 271RXGP274, and 37LXLNDG42 on E2 and 38CKGVP42, W81, and D100/V107 on Erns. Particularly, E213 of E2 is field isolate-specific, while N40 of E2 and D100/V107 of Erns are vaccine strain-specific. Results from our study further indicate that N40D of E2 mutation in field strains was likely produced under positive selection associated with long-term mass vaccination, leading to CSFV evasion of host immune response. Taking together, this study provides new insights into the antigenic structure of CSFV E2 and Erns and the differentiating mAbs will contribute to the development of a diagnostic strategy to differentiate C-strain vaccination from natural infection (DIVA) of CSFV in terms of elimination of CSF in China.
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Affiliation(s)
- Shijiang Mi
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonoses Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Lihua Wang
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States
| | - Hongwei Li
- School of Biotechnology, Southern Medical University, Guangzhou, China
| | - Fei Bao
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Rachel Madera
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States
| | - Xiju Shi
- Institute of Animal Qurantine Reserach, Science and Technology Research Center of China Customs, Beijing, China
| | - Liying Zhang
- College of Animal Science and Technology, Jilin University, Changchun, China
| | - Yingying Mao
- School of Biotechnology, Southern Medical University, Guangzhou, China
| | - Renhe Yan
- Department of Research & Development, Guangzhou Bioneeds Biotechnology Co., Ltd, Guangzhou, China
| | - Xianzhu Xia
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonoses Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Wenjie Gong
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonoses Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
- *Correspondence: Changchun Tu, ; Jishu Shi, ; Wenjie Gong,
| | - Jishu Shi
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States
- *Correspondence: Changchun Tu, ; Jishu Shi, ; Wenjie Gong,
| | - Changchun Tu
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonoses Research of the Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China
- *Correspondence: Changchun Tu, ; Jishu Shi, ; Wenjie Gong,
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Li J, Li X, Ma H, Ren X, Hao G, Zhang H, Zhao Z, Fang K, Li X, Rong Z, Sun S, Chen H, Qian P. Efficient mucosal vaccination of a novel classical swine fever virus E2-Fc fusion protein mediated by neonatal Fc receptor. Vaccine 2020; 38:4574-4583. [PMID: 32417139 DOI: 10.1016/j.vaccine.2020.05.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/04/2020] [Accepted: 05/05/2020] [Indexed: 12/23/2022]
Abstract
Classical swine fever (CSF) remains one of the most important highly contagious and fatal viral disease of swine with high morbidity and mortality. CSF is caused by classical swine fever virus (CSFV), a small, enveloped RNA virus of the genus Pestivirus. The aim of this study was to construct the a novel CSFV Fc-fusion recombinant protein and evaluate the efficacy as a vaccine against CSFV. Here, we obtained a novel subunit vaccine expressing CSFV E2 recombinant fusion protein in CHO-S cells. Functional analysis revealed that CSFV Fc-fusion recombinant protein (CSFV-E2-Fc) could bind to FcγRI on antigen-presenting cells (APCs) and significantly increase IgA levels in serum and feces, inducing stronger mucosal immune response in swine. Additionally, CSFV-E2-Fc immunization enhanced CSFV-specific T cell immune response with a Th1-like pattern of cytokine secretion, remarkably stimulated the Th1-biased cellular immune response and humoral immune response. Further, the protective effects of CSFV-E2-Fc subunit vaccines were confirmed. The data suggest that CSFV E2-Fc recombinant fusion protein may be a promising candidate subunit vaccine to elicit immune response and protect against CSFV.
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Affiliation(s)
- Jianglong Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Xiangmin Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, 430070, China
| | - Hui Ma
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Xujiao Ren
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Genxi Hao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Huawei Zhang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Zekai Zhao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Kui Fang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Xinxin Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Zhenxiang Rong
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Shaohua Sun
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China
| | - Huanchun Chen
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, 430070, China
| | - Ping Qian
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, China; Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, 430070, China.
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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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Complex Virus-Host Interactions Involved in the Regulation of Classical Swine Fever Virus Replication: A Minireview. Viruses 2017; 9:v9070171. [PMID: 28678154 PMCID: PMC5537663 DOI: 10.3390/v9070171] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 06/15/2017] [Accepted: 06/27/2017] [Indexed: 02/06/2023] Open
Abstract
Classical swine fever (CSF), caused by classical swine fever virus (CSFV), is one of the most devastating epizootic diseases of pigs in many countries. Viruses are small intracellular parasites and thus rely on the cellular factors for replication. Fundamental aspects of CSFV-host interactions have been well described, such as factors contributing to viral attachment, modulation of genomic replication and translation, antagonism of innate immunity, and inhibition of cell apoptosis. However, those host factors that participate in the viral entry, assembly, and release largely remain to be elucidated. In this review, we summarize recent progress in the virus-host interactions involved in the life cycle of CSFV and analyze the potential mechanisms of viral entry, assembly, and release. We conclude with future perspectives and highlight areas that require further understanding.
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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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Li W, Wang G, Liang W, Kang K, Guo K, Zhang Y. Integrin β3 is required in infection and proliferation of classical swine fever virus. PLoS One 2014; 9:e110911. [PMID: 25340775 PMCID: PMC4207786 DOI: 10.1371/journal.pone.0110911] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 09/24/2014] [Indexed: 12/25/2022] Open
Abstract
Classical Swine Fever (CSF) is a highly infectious fatal pig disease, resulting in huge economic loss to the swine industry. Integrins are membrane-bound signal mediators, expressed on a variety of cell surfaces and are known as receptors or co-receptors for many viruses. However, the role of integrin β3 in CSFV infection is unknown. Here, through quantitive PCR, immunofluorescence (IFC) and immunocytohistochemistry (ICC), we revealed that ST (swine testicles epithelial) cells have a prominent advantage in CSFV proliferation as compared to EC (swine umbilical vein endothelial cell), IEC (swine intestinal epithelial cell) and PK (porcine kidney epithelial) cells. Meanwhile, ST cells had remarkably more integrin β3 expression as compared to EC, IEC and PK cells, which was positively correlated with CSFV infection and proliferation. Integrin β3 was up-regulated post CSFV infection in all the four cell lines, while the CSFV proliferation rate was decreased in integrin β3 function-blocked cells. ShRNA1755 dramatically decreased integrin β3, with a deficiency of 96% at the mRNA level and 80% at the protein level. CSFV proliferation was dramatically reduced in integrin β3 constantly-defected cells (ICDC), with the deficiencies of 92.6%, 99% and 81.7% at 24 h, 48 h and 72 h post CSFV infection, respectively. These results demonstrate that integrin β3 is required in CSFV infection and proliferation, which provide a new insight into the mechanism of CSFV infection.
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Affiliation(s)
- Weiwei Li
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Gang Wang
- Jiangsu Key Laboratory of Biological Cancer Therapy, Xuzhou Medical College, Xuzhou, Jiangsu, China
| | - Wulong Liang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Kai Kang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Kangkang Guo
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Yanming Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
- * E-mail:
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8
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Huang YL, Deng MC, Wang FI, Huang CC, Chang CY. The challenges of classical swine fever control: modified live and E2 subunit vaccines. Virus Res 2013; 179:1-11. [PMID: 24211665 DOI: 10.1016/j.virusres.2013.10.025] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 10/22/2013] [Accepted: 10/25/2013] [Indexed: 01/15/2023]
Abstract
Classical swine fever (CSF) is an economically important, highly contagious disease of swine worldwide. CSF is caused by classical swine fever virus (CSFV), and domestic pigs and wild boars are its only natural hosts. The two main strategies used to control CSF epidemic are systematic prophylactic vaccination and a non-vaccination stamping-out policy. This review compares the protective efficacy of the routinely used modified live vaccine (MLV) and E2 subunit vaccines and summarizes the factors that influence the efficacy of the vaccines and the challenges that both vaccines face to CSF control. Although MLV provide earlier and more complete protection than E2 subunit vaccines, it has the drawback of not allowing differentiation between infected and vaccinated animals (DIVA). The marker vaccine of E2 protein with companion discriminatory test to detect antibodies against E(rns) allows DIVA and is a promising strategy for future control and eradication of CSF. Maternal derived antibody (MDA) is the critical factor in impairing the efficacy of both MLV and E2 subunit vaccines, so the well-designed vaccination programs of sows and piglets should be considered together. Because of the antigen variation among various genotypes of CSFV, antibodies raised by either MLV or subunit vaccine neutralize genotypically homologous strains better than heterologous ones. However, although this is not a major concern for MLV as the induced immune responses can protect pigs against the challenge of various genotypes of CSFVs, it is critical for E2 subunit vaccines. It is thus necessary to evaluate whether the E2 subunit vaccine can completely protect against the current prevalent strains in the field. An ideal new generation of vaccine should be able to maintain the high protective efficiency of MLV and overcome the problem of antigenic variations while allowing for DIVA.
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Affiliation(s)
- Yu-Liang Huang
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, New Taipei City 25158, Taiwan
| | - Ming-Chung Deng
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, New Taipei City 25158, Taiwan
| | - Fun-In Wang
- School of Veterinary Medicine, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei 10617, Taiwan
| | - Chin-Cheng Huang
- Pingtung Agriculture Biotechnology Park, Council of Agriculture, No. 1 Shennong Road, Dehe Village, Changjhih Township, Pingtung County 90846, Taiwan
| | - Chia-Yi Chang
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, New Taipei City 25158, Taiwan.
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9
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Identification of conformational epitopes and antigen-specific residues at the D/A domains and the extramembrane C-terminal region of E2 glycoprotein of classical swine fever virus. Virus Res 2012; 168:56-63. [PMID: 22727685 DOI: 10.1016/j.virusres.2012.06.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 06/10/2012] [Accepted: 06/12/2012] [Indexed: 11/20/2022]
Abstract
Envelope glycoprotein E2 of classical swine fever virus (CSFV) is the major antigen that induces neutralizing antibodies in infected pigs. Previous studies revealed that both conformation-dependent and linear epitopes are most present within domains B/C/D/A in the N-terminal half of E2. However, studies of antigenicity beyond the B/C domains remain limited. This study revealed that conformational epitopes were present on the D/A domains as well as the proximal C-terminal of E2, since the mutation of cysteine abrogated their bindings to monoclonal antibodies (mAbs). The residue R845 at domain A and E902 at the C-terminal region were critical for specific binding to mAbs, further supporting the presence of antigenic determinants on these regions. Substitutions of cysteines in domains D/A not only abrogated the binding to mAbs directed to D/A, but also affected the binding of the downstream C-terminal region to its specific mAbs, suggesting a close interaction between the two conformational epitopes. Mutations on the five proximal cysteines at positions 869, 877, 893, 896 and 930 in the C-terminal region only affected the binding to its specific mAbs binding sites. In addition, mutation on the three distal C-terminal cysteines at positions 945, 966, and 983 resulted in loss of E2 homodimerization. This study demonstrates new antigenic epitopes on D/A domains and C-terminal of E2 that have not been reported before, and that the nine cysteines in the C-terminal function differently in either maintaining the antigenic structure or in intermolecular dimerization of E2.
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Graham SP, Everett HE, Haines FJ, Johns HL, Sosan OA, Salguero FJ, Clifford DJ, Steinbach F, Drew TW, Crooke HR. Challenge of pigs with classical swine fever viruses after C-strain vaccination reveals remarkably rapid protection and insights into early immunity. PLoS One 2012; 7:e29310. [PMID: 22235283 PMCID: PMC3250419 DOI: 10.1371/journal.pone.0029310] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 11/25/2011] [Indexed: 11/19/2022] Open
Abstract
Pre-emptive culling is becoming increasingly questioned as a means of controlling animal diseases, including classical swine fever (CSF). This has prompted discussions on the use of emergency vaccination to control future CSF outbreaks in domestic pigs. Despite a long history of safe use in endemic areas, there is a paucity of data on aspects important to emergency strategies, such as how rapidly CSFV vaccines would protect against transmission, and if this protection is equivalent for all viral genotypes, including highly divergent genotype 3 strains. To evaluate these questions, pigs were vaccinated with the Riemser® C-strain vaccine at 1, 3 and 5 days prior to challenge with genotype 2.1 and 3.3 challenge strains. The vaccine provided equivalent protection against clinical disease caused by for the two challenge strains and, as expected, protection was complete at 5 days post-vaccination. Substantial protection was achieved after 3 days, which was sufficient to prevent transmission of the 3.3 strain to animals in direct contact. Even by one day post-vaccination approximately half the animals were partially protected, and were able to control the infection, indicating that a reduction of the infectious potential is achieved very rapidly after vaccination. There was a close temporal correlation between T cell IFN-γ responses and protection. Interestingly, compared to responses of animals challenged 5 days after vaccination, challenge of animals 3 or 1 days post-vaccination resulted in impaired vaccine-induced T cell responses. This, together with the failure to detect a T cell IFN-γ response in unprotected and unvaccinated animals, indicates that virulent CSFV can inhibit the potent antiviral host defences primed by C-strain in the early period post vaccination.
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Affiliation(s)
- Simon P. Graham
- Virology Department, Animal Health and Veterinary Laboratories Agency, Addlestone, United Kingdom
| | - Helen E. Everett
- Virology Department, Animal Health and Veterinary Laboratories Agency, Addlestone, United Kingdom
| | - Felicity J. Haines
- Virology Department, Animal Health and Veterinary Laboratories Agency, Addlestone, United Kingdom
| | - Helen L. Johns
- Virology Department, Animal Health and Veterinary Laboratories Agency, Addlestone, United Kingdom
| | - Olubukola A. Sosan
- Virology Department, Animal Health and Veterinary Laboratories Agency, Addlestone, United Kingdom
| | - Francisco J. Salguero
- Pathology and Host Susceptibility Department, Animal Health and Veterinary Laboratories Agency, Addlestone, United Kingdom
| | - Derek J. Clifford
- Specialist Scientific Services, Animal Health and Veterinary Laboratories Agency, Addlestone, United Kingdom
| | - Falko Steinbach
- Virology Department, Animal Health and Veterinary Laboratories Agency, Addlestone, United Kingdom
| | - Trevor W. Drew
- Virology Department, Animal Health and Veterinary Laboratories Agency, Addlestone, United Kingdom
| | - Helen R. Crooke
- Virology Department, Animal Health and Veterinary Laboratories Agency, Addlestone, United Kingdom
- * E-mail:
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Li J, Dai Y, Liu S, Guo H, Wang T, Ouyang H, Tu C. In vitro inhibition of CSFV replication by multiple siRNA expression. Antiviral Res 2011; 91:209-16. [PMID: 21699919 PMCID: PMC7114328 DOI: 10.1016/j.antiviral.2011.06.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 05/24/2011] [Accepted: 06/01/2011] [Indexed: 01/24/2023]
Abstract
Classical swine fever (CSF) is a highly contagious viral disease of pigs which causes major economic losses worldwide. No specific drug is currently available for the effective treatment of CSFV infection; however, RNA interference (RNAi) has been applied successfully to inhibit the replication of human and other animal viruses. In this study, three effective siRNAs targeting NS3 of CSFV were selected. siNS3-2 targeting NS3 gene was chosen for further experimentation, while siN1 and siN2 targeting Npro gene, and siNS5B targeting NS5B gene describe previously. Single, double and quadruple anti-CSFV siRNA expression plasmids, with loxp sites at each end of the selectable marker genes, were constructed and analyzed using the same promoters or four different promoters, targeting Npro, NS3 and NS5B genes of CSFV. Results indicate that single or multiple siRNA expression plasmids can efficiently inhibit CSFV replication and that inhibition was markedly stronger when multiple siRNAs were expressed targeting different genes of CSFV. Since RNAi applied to anti-CSFV research, this study provides anti-CSFV methods by single and multiple siRNA expression which can target most viral isolates of different subtypes and prevent viral escape. It also provides a basis for development of CSFV-resistant transgenic pigs.
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Affiliation(s)
- Jiangnan Li
- Institute of Veterinary Sciences, Academy of Military Medical Sciences, 666 Liuying West Road, Changchun 130122, China
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Chen N, Tong C, Li D, Wan J, Yuan X, Li X, Peng J, Fang W. Antigenic analysis of classical swine fever virus E2 glycoprotein using pig antibodies identifies residues contributing to antigenic variation of the vaccine C-strain and group 2 strains circulating in China. Virol J 2010; 7:378. [PMID: 21194462 PMCID: PMC3025870 DOI: 10.1186/1743-422x-7-378] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Accepted: 12/31/2010] [Indexed: 11/10/2022] Open
Abstract
Background Glycoprotein E2, the immunodominant protein of classical swine fever virus (CSFV), can induce neutralizing antibodies and confer protective immunity in pigs. Our previous phylogenetic analysis showed that subgroup 2.1 viruses branched away from subgroup 1.1, the vaccine C-strain lineage, and became dominant in China. The E2 glycoproteins of CSFV C-strain and recent subgroup 2.1 field isolates are genetically different. However, it has not been clearly demonstrated how this diversity affects antigenicity of the protein. Results Antigenic variation of glycoprotein E2 was observed not only between CSFV vaccine C-strain and subgroup 2.1 strains, but also among strains of the same subgroup 2.1 as determined by ELISA-based binding assay using pig antisera to the C-strain and a representative subgroup 2.1 strain QZ-07 currently circulating in China. Antigenic incompatibility of E2 proteins markedly reduced neutralization efficiency against heterologous strains. Single amino acid substitutions of D705N, L709P, G713E, N723S, and S779A on C-strain recombinant E2 (rE2) proteins significantly increased heterologous binding to anti-QZ-07 serum, suggesting that these residues may be responsible for the antigenic variation between the C-strain and subgroup 2.1 strains. Notably, a G713E substitution caused the most dramatic enhancement of binding of the variant C-strain rE2 protein to anti-QZ-07 serum. Multiple sequence alignment revealed that the glutamic acid residue at this position is conserved within group 2 strains, while the glycine residue is invariant among the vaccine strains, highlighting the role of the residue at this position as a major determinant of antigenic variation of E2. A variant Simpson's index analysis showed that both codons and amino acids of the residues contributing to antigenic variation have undergone similar diversification. Conclusions These results demonstrate that CSFV vaccine C-strain and group 2 strains circulating in China differ in the antigenicity of their E2 glycoproteins. Systematic site-directed mutagenesis of the antigenic units has revealed residues that limit cross-reactivity. Our findings may be useful for the development of serological differential assays and improvement of immunogenicity of novel classical swine fever vaccines.
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Affiliation(s)
- Ning Chen
- Institute of Preventive Veterinary Medicine, Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310029, PR China
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Li J, Guo H, Shi Z, Tu C. In vitro inhibition of CSFV replication by retroviral vector-mediated RNA interference. J Virol Methods 2010; 169:316-21. [PMID: 20691206 PMCID: PMC7112837 DOI: 10.1016/j.jviromet.2010.07.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2010] [Revised: 07/28/2010] [Accepted: 07/29/2010] [Indexed: 11/30/2022]
Abstract
Classical swine fever (CSF) is a highly contagious viral disease of pigs which causes major economic losses worldwide. No specific drug is currently available for the effective treatment of CSFV infection. RNA interference (RNAi) technology depends on effective delivery systems, for which several effective vectors have recently been developed. Three retroviral plasmids containing siRNA genes targeting different regions of Npro and NS4A have been constructed, and 3 replication-incompetent retroviral vectors have been produced in the human embryo kidney cell line GP2-293 by retroviral plasmid transfection. PK-15 cells were then infected with these replication-incompetent retroviral vectors and screened for siRNA stably expressing PK-15 cell clones. Growth of CSFV in such siRNA stably expressing cell clones resulted in a 186-fold reduction in viral genome copies and, at 72 h post-infection, only a small % of cells showed infection by indirect immunofluorescence microscopy, and effective inhibition of virus replication persisted for up to 120 h. Retroviral vector-mediated RNAi can therefore be used to study the specific function of viral genes associated with CSFV replication and may have potential therapeutic application.
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Affiliation(s)
- Jiangnan Li
- College of Animal Science and Veterinary Medicine, Jilin University, 5333 XiAn Da Road, Changchun 130062, China
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Chang CY, Huang CC, Lin YJ, Deng MC, Tsai CH, Chang WM, Wang FI. Identification of antigen-specific residues on E2 glycoprotein of classical swine fever virus. Virus Res 2010; 152:65-72. [PMID: 20558217 DOI: 10.1016/j.virusres.2010.06.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 06/02/2010] [Accepted: 06/07/2010] [Indexed: 10/19/2022]
Abstract
Envelope glycoprotein E2 of classical swine fever virus (CSFV) is the major antigen that induces neutralizing antibodies in infected pigs. Our previous study revealed that N-terminal 90 residues (domains B/C) of E2 play key roles in differentiating vaccine strain LPC/AHRI (subgroup 1.1) from the two field strains TD/96/TWN (subgroup 2.1) and 94.4/IL/94/TWN (subgroup 3.4) (Chang et al., 2010). This study further analyzed the reaction patterns between monoclonal antibodies (mAbs) and expressed hybrid N-terminal of E2 of the above-mentioned viruses, revealing that mAbs T33 and C2, mAbs V8 and T23, and mAbs L7 and L150 required binding sites specifically at residues 690-714 in domain B, residues 715-740 in domain C, and residues 741-765 in domain C, respectively. Site-directed mutagenesis further demonstrated that residues (713)E and (729)D were critical for antigenic specificity of field strain (94.4/IL/94/TWN), while residues (705)D and (761)K were specific for vaccine strain (LPC/AHRI). These specific residues likely mediated in determining the topography of mAb binding sites of E2 to allow for differentiation between strains based on the premise that the structural integrity of the conformational epitope is maintained.
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Affiliation(s)
- Chia-Yi Chang
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, Taipei, Taiwan
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Antigenic domains analysis of classical swine fever virus E2 glycoprotein by mutagenesis and conformation-dependent monoclonal antibodies. Virus Res 2010; 149:183-9. [DOI: 10.1016/j.virusres.2010.01.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Revised: 01/26/2010] [Accepted: 01/26/2010] [Indexed: 11/17/2022]
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