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Wu X, Wang Q, Lu W, Wang Y, Han Z, Liang L, Gao S, Ma H, Luo X. The PCV3 Cap Virus-like Particle Vaccine with the Chimeric PCV2-Neutralizing Epitope Gene Is Effective in Mice. Vet Sci 2024; 11:264. [PMID: 38922011 PMCID: PMC11209062 DOI: 10.3390/vetsci11060264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 06/01/2024] [Accepted: 06/06/2024] [Indexed: 06/27/2024] Open
Abstract
Porcine circovirus type 3 (PCV3) infection can cause symptoms similar to those of porcine circovirus type 2 (PCV2) infection, and coinfections with both PCV2 and PCV3 are observed in the swine industry. Consequently, developing chimeric vaccines is essential to prevent and control porcine circovirus infections. In this study, we used both E. coli and mammalian expression systems to express PCV3 Cap (Cap3) and a chimeric gene containing the PCV2-neutralizing epitope within the PCV3 Cap (Cap3-Cap2E), which were assembled into virus-like particle (VLP) vaccines. We found that Cap3 lacking nuclear localization signal (NLS) could not form VLPs, while Cap3 with a His-tag successfully assembled into VLPs. Additionally, the chimeric of PCV2-neutralizing epitopes did not interfere with the assembly process of VLPs. Various immunization approaches revealed that pCap3-Cap2E VLP vaccines were capable of activating high PCV3 Cap-specific antibody levels and effectively neutralizing both PCV3 and PCV2. Furthermore, pCap3-Cap2E VLPs demonstrated a potent ability to activate cellular immunity, protecting against PCV3 infection and preventing lung damage in mice. In conclusion, this study successfully developed a PCV3 Cap VLP vaccine incorporating chimeric PCV2-neutralizing epitope genes, providing new perspectives for PCV3 vaccine development.
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Affiliation(s)
- Xingchen Wu
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China; (X.W.)
| | - Qikai Wang
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China; (X.W.)
| | - Wang Lu
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China; (X.W.)
| | - Ying Wang
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China; (X.W.)
| | - Zehao Han
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China; (X.W.)
| | - Libin Liang
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China; (X.W.)
| | - Shimin Gao
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China; (X.W.)
| | - Haili Ma
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China; (X.W.)
| | - Xiaomao Luo
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China; (X.W.)
- Shanxi Academy of Advanced Research and Innovation, Taiyuan 030012, China
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Wang Y, Su M, Huang Y, Ren J, Niu S, Zhao Y, Yan F, Yan Y, Tian WX. Development of a novel PCV2 and PCV3 vaccine using virus-like vesicles incorporating Venezuelan equine encephalomyelitis virus-containing vesicular stomatitis virus glycoprotein. Front Vet Sci 2024; 11:1359421. [PMID: 38840631 PMCID: PMC11150706 DOI: 10.3389/fvets.2024.1359421] [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: 01/24/2024] [Accepted: 05/06/2024] [Indexed: 06/07/2024] Open
Abstract
Porcine circovirus disease (PCV) causes substantial economic losses in the pig industry, primarily from porcine circovirus type 2 (PCV2) and porcine circovirus type 3 (PCV3). Novel vaccines are necessary to prevent and control PCV infections. PCV coat proteins are crucial for eliciting immunogenic proteins that induce the production of antibodies and immune responses. A vaccine platform utilizing Semliki Forest virus RNA replicons expressing vesicular stomatitis virus glycoprotein (VSV-G), was recently developed. This platform generates virus-like vesicles (VLVs) containing VSV-G exclusively, excluding other viral structural proteins. In our study, we developed a novel virus-like vesicle vaccine by constructing recombinant virus-like vesicles (rVLVs) that also express EGFP. These rVLVs were created using the RNA replicon of Venezuelan equine encephalomyelitis (VEEV) and New Jersey serotype VSV-G. The rVLVs underwent characterization and safety evaluation in vitro. Subsequently, rVLVs expressing PCV2d-Cap and PCV3-Cap proteins were constructed. Immunization of C57 mice with these rVLVs led to a significant increase in anti-porcine circovirus type 2 and type 3 capsid protein antibodies in mouse serum. Additionally, a cellular immune response was induced, as evidenced by high production of IFN-γ and IL-4 cytokines. Overall, this study demonstrates the feasibility of developing a novel porcine circovirus disease vaccine based on rVLVs.
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Affiliation(s)
| | | | | | | | | | | | | | - Yi Yan
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong, China
| | - Wen-xia Tian
- College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong, China
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Jiao Q, Yang L, Liu X, Wen Y, Tian L, Qian P, Chen H, Li X. Isolation and pathogenicity of porcine circovirus type 2 in mice from Guangxi province, China. Virol J 2023; 20:195. [PMID: 37644571 PMCID: PMC10466715 DOI: 10.1186/s12985-023-02161-5] [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: 06/19/2023] [Accepted: 08/15/2023] [Indexed: 08/31/2023] Open
Abstract
BACKGROUND Porcine circovirus type 2 (PCV2), a member of the genus Circovirus and family Circoviridae, is a closed, small, circular, and single-stranded DNA virus, and it is a crucial swine pathogen of porcine circovirus-associated diseases (PCVADs). PCV2 was first detected in PK-15(ATCC-CCL) cells in 1974, which has caused significant economic loss to the swine industry throughout the world. And the first case of PCV2 was reported in China in 2000. At present, PCV2d is the main genotype circulating widely in China. METHODS Lymph samples were obtained from piglets with emaciation and respiratory disease in Guangxi province, China. The main pathogens were detected via PCR from lymph samples, and then PCV2-single positive samples were used to inoculate with PK-15 cells. After successive generations, the isolate was subsequently identified by polymerase chain reaction (PCR), immunofluorescence assay (IFA), Western blot (WB), and transmission electron microscopic (TEM). The full-length genome and genetic characterization of isolates were analyzed by Sanger sequencing. The TCID50 of the PCV2-GX-6 was determined by IFA, and the pathogenicity of PCV2 in BALB/c mice was analyzed via the mouse model. RESULTS The isolates were successfully isolated from clinical samples. The complete genome of PCV2-GX-4, PCV2-GX-6, PCV2-GX-7, PCV2-GX-11 and PCV2-GX-16 have been amplified, sequenced, and deposited in GenBank (accession no.: OR133747, OQ803314, OR133748, OR133749, OR133750). Homology and phylogenetic analysis with reference strains showed that the isolates belonged to the PCV2d genotype. The PCV2-GX-6 could be stably passaged more than 30 times in PK-15 cells. PCV2-GX-6 was identified by PCR, IFA, WB and TEM. The results of homology showed that PCV2-GX-6 was closely related to the reference strains PCV2-JS17-8 (GenBank accession no.: MH211363). Pathogenicity studies in mice have shown that PCV2-GX-6 can lead to growth inhibition of mice. Meanwhile PCV2-GX-6 caused the typical lesions of spleen, lung and kidney. The results of qPCR showed that PCV2 can effectively proliferate in the liver, spleen, lung, and kidney. CONCLUSION PCV2-GX-6 can successfully infect BLAB/c mice, effectively proliferate in major organs, and possessed high pathogenicity. In conclusion, combined with the genotype and pathogenicity of PCV2d currently prevalent, PCV2-GX-6 can be used as a candidate vaccine strain.
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Affiliation(s)
- Qiulin Jiao
- National Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
| | - Liuyue Yang
- National Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
| | - Xiangzu Liu
- National Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
| | - Yanwen Wen
- National Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
| | - Linxing Tian
- National Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
| | - Ping Qian
- National Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, the Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, 430070, PR China
| | - Huanchun Chen
- National Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, the Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, 430070, PR China
| | - Xiangmin Li
- National Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China.
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China.
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, the Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, 430070, PR China.
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Maity HK, Samanta K, Deb R, Gupta VK. Revisiting Porcine Circovirus Infection: Recent Insights and Its Significance in the Piggery Sector. Vaccines (Basel) 2023; 11:1308. [PMID: 37631876 PMCID: PMC10457769 DOI: 10.3390/vaccines11081308] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 07/29/2023] [Accepted: 07/29/2023] [Indexed: 08/27/2023] Open
Abstract
Porcine circovirus (PCV), a member of the Circoviridae family within the genus Circovirus, poses a significant economic risk to the global swine industry. PCV2, which has nine identified genotypes (a-i), has emerged as the predominant genotype worldwide, particularly PCV2d. PCV2 has been commonly found in both domestic pigs and wild boars, and sporadically in non-porcine animals. The virus spreads among swine populations through horizontal and vertical transmission routes. Despite the availability of commercial vaccines for controlling porcine circovirus infections and associated diseases, the continuous genotypic shifts from a to b, and subsequently from b to d, have maintained PCV2 as a significant pathogen with substantial economic implications. This review aims to provide an updated understanding of the biology, genetic variation, distribution, and preventive strategies concerning porcine circoviruses and their associated diseases in swine.
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Affiliation(s)
- Hemanta Kumar Maity
- Department of Avian Science, Faculty of Veterinary & Animal Science, West Bengal University of Animal & Fishery Sciences, Kolkata 700037, West Bengal, India
| | - Kartik Samanta
- Department of Avian Science, Faculty of Veterinary & Animal Science, West Bengal University of Animal & Fishery Sciences, Kolkata 700037, West Bengal, India
| | - Rajib Deb
- ICAR-National Research Center on Pig, Rani, Guwahati 781131, Assam, India
| | - Vivek Kumar Gupta
- ICAR-National Research Center on Pig, Rani, Guwahati 781131, Assam, India
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Fan M, Bian L, Tian X, Hu Z, Wu W, Sun L, Yuan G, Li S, Yue L, Wang Y, Wu L, Wang Y, Yan Z, Ren J, Li X. Infection characteristics of porcine circovirus type 2 in different herds from intensive farms in China, 2022. Front Vet Sci 2023; 10:1187753. [PMID: 37397003 PMCID: PMC10311082 DOI: 10.3389/fvets.2023.1187753] [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: 03/16/2023] [Accepted: 05/31/2023] [Indexed: 07/04/2023] Open
Abstract
Introduction Porcine circovirus type 2 (PCV2) is the primary etiological agent of porcine circovirus diseases (PCVD), which are widespread in most pig herds, causing huge economic losses in the global pig industry. Therefore, it is critical to assess the infection characteristics of PCV2 in different swine herds to develop effective strategies against PCVD. Methods In this study, routine diagnostic and monitoring protocols were used to collect 12,714 samples from intensive farms in China, and PCV2 was tested for by qPCR to determine positivity rates and viral loads in samples from different herds and materials. Results PCV2 was found to be prevalent throughout China, and fattening farms had higher positivity rates than breeding farms. The PCV2 positivity rates in breeding farms in Southern China were higher than those in Northern China. Growing-finishing pigs demonstrated the highest positivity rate in the tested samples, while pre-weaning piglets and adult sows had the lowest. Meanwhile, samples with viral loads exceeding 106 copies/mL in growing-finishing pigs had 27.2% positivity, compared to 1.9% and 3.3% in sows and piglets, respectively. The results of the viral loads in the serum samples followed a similar trend. Discussion The findings reveal that PCV2 circulates in different herds from intensive farms, with positivity increasing from pre-weaning to growing-finishing herds. It is urgent to develop effective strategies to reduce PCV2 positivity in growing-finishing herds and prevent viral circulation among pigs.
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Affiliation(s)
- Mingyu Fan
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd. (NHLH Academy of Swine Research), Dezhou, China
- Shandong Swine Health Data and Intelligent Monitoring Project Laboratory, Dezhou University, Dezhou, China
| | - Lujie Bian
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd. (NHLH Academy of Swine Research), Dezhou, China
| | - Xiaogang Tian
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd. (NHLH Academy of Swine Research), Dezhou, China
| | - Zhiqiang Hu
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd. (NHLH Academy of Swine Research), Dezhou, China
| | - Weisheng Wu
- Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd., Dezhou, China
| | - Leilei Sun
- New Hope Liuhe Co., Ltd., Chengdu, China
| | | | | | - Lei Yue
- New Hope Liuhe Co., Ltd., Chengdu, China
| | - Ying Wang
- New Hope Liuhe Co., Ltd., Chengdu, China
| | - Lili Wu
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd. (NHLH Academy of Swine Research), Dezhou, China
| | - Yongquan Wang
- Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd., Dezhou, China
| | - Zheng Yan
- New Hope Liuhe Co., Ltd., Chengdu, China
| | - Jing Ren
- Shandong Swine Health Data and Intelligent Monitoring Project Laboratory, Dezhou University, Dezhou, China
| | - Xiaowen Li
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd. (NHLH Academy of Swine Research), Dezhou, China
- Shandong Swine Health Data and Intelligent Monitoring Project Laboratory, Dezhou University, Dezhou, China
- Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd., Dezhou, China
- New Hope Liuhe Co., Ltd., Chengdu, China
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Xu T, Xiong T, Xie W, Wu J, Liu X, Li G, Lv Y, Li L, Yang Z, Wang H, Liu D, Chen R. Construction and Evaluation of the Immunogenicity and Protective Efficacy of Recombinant Replication-Deficient Human Adenovirus-5 Expressing Genotype VII Newcastle Disease Virus F Protein and Infectious Bursal Disease Virus VP2 Protein. Vaccines (Basel) 2023; 11:1051. [PMID: 37376440 DOI: 10.3390/vaccines11061051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 05/18/2023] [Accepted: 05/26/2023] [Indexed: 06/29/2023] Open
Abstract
Newcastle disease (ND) and infectious bursal disease (IBD) are two key infectious diseases that significantly threaten the health of the poultry industry. Although existing vaccinations can effectively prevent and treat these two diseases through multiple immunizations, frequent immunization stresses significantly impact chicken growth. In this study, three recombinant adenoviruses, rAd5-F expressing the NDV (genotype VII) F protein, rAd5-VP2 expressing the IBDV VP2 protein, and rAd5-VP2-F2A-F co-expressing F and VP2 proteins, were constructed using the AdEasy system. The F and VP2 genes of the recombinant adenoviruses could be transcribed and expressed normally in HEK293A cells as verified by RT-PCR and Western blot. The three recombinant viruses were shown to have similar growth kinetics as rAd5-EGFP. Compared with the PBS and rAd5-EGFP groups, SPF chickens immunized with recombinant adenoviruses produced higher antibody levels, more significant lymphocyte proliferation, and significantly higher CD4+/CD3+ and CD8+/CD3+ cells in peripheral blood. The survival rate of SPF chickens immunized with rAd5-F and rAd5-VP2-F2A-F after the challenge with DHN3 was 100%, and 86% of SPF chickens showed no viral shedding at 7 dpc. The survival rate of SPF chickens immunized with rAd5-VP2 and rAd5-VP2-F2A-F after the challenge with BC6/85 was 86%. rAd5-VP2 and rAd5-VP2-F2A-F significantly inhibited bursal atrophy and pathological changes compared to the rAd5-EGFP and PBS groups. This study provides evidence that these recombinant adenoviruses have the potential to be developed into safe and effective vaccine candidates for the prevention and control of ND and IBD.
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Affiliation(s)
- Ting Xu
- Zhaoqing Branch of Guangdong Laboratory of Lingnan Modern Agricultural Science and Technology, Zhaoqing 526238, China
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, China
| | - Ting Xiong
- Zhaoqing Branch of Guangdong Laboratory of Lingnan Modern Agricultural Science and Technology, Zhaoqing 526238, China
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, China
| | - Wenting Xie
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, China
| | - Jing Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, China
| | - Xiao Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, China
| | - Guimin Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, China
| | - Yadi Lv
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, China
| | - Linyu Li
- Zhaoqing Branch of Guangdong Laboratory of Lingnan Modern Agricultural Science and Technology, Zhaoqing 526238, China
| | - Zekun Yang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, China
| | - Han Wang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, China
| | - Dingxiang Liu
- Zhaoqing Branch of Guangdong Laboratory of Lingnan Modern Agricultural Science and Technology, Zhaoqing 526238, China
- Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China
| | - Ruiai Chen
- Zhaoqing Branch of Guangdong Laboratory of Lingnan Modern Agricultural Science and Technology, Zhaoqing 526238, China
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510640, China
- Key Laboratory of Biotechnology and Bioproducts Development for Animal Epidemic Prevention, Ministry of Agriculture and Rural Affairs, Zhaoqing 526238, China
- Guangdong Enterprise Key Laboratory of Biotechnology R&D of Veterinary Biologics, Zhaoqing 526238, China
- Zhaoqing Dahuanong Biology Medicine Co., Ltd., Zhaoqing 526238, China
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Du Q, Shi T, Wang H, Zhu C, Yang N, Tong D, Huang Y. The ultrasonically treated nanoliposomes containing PCV2 DNA vaccine expressing gC1qR binding site mutant Cap is efficient in mice. Front Microbiol 2023; 13:1077026. [PMID: 36713188 PMCID: PMC9874303 DOI: 10.3389/fmicb.2022.1077026] [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: 10/22/2022] [Accepted: 12/28/2022] [Indexed: 01/12/2023] Open
Abstract
Nowadays, vaccines are broadly used to prevent porcine circovirus type 2 (PCV2) infection-induced expenditures, but the virus is still spreading among pigs. The current PCV2 vaccines all rely on the immunogenicity of Cap, yet our previous studies found that Cap is also the major component mediating the PCV2 infection-induced immune suppression through its interaction with host gC1qR. Thereby, new vaccines are still necessary for PCV2 prevention and control. In this study, we constructed a new PCV2 DNA vaccine expressing the gC1qR binding site mutant Cap. We introduced the Intron A and WPRE elements into the vector to improve the Cap expression level, and fused the IL-2 secretory signal peptides to the N-terminal of Cap to mediate the secretion of Cap. We also screened and selected chemokines CXCL12, CCL22, and CCL25 to migrate dendritic cells. In addition, we contained the vectors with PEI and then ultrasonic them into nano size to enhance the entrance of the vectors. Finally, the animal experiments showed that the new PCV2 DNA vaccine expressing the gC1qR binding site mutant Cap could induce stronger humoral and cellular immune responses than the PCV2 DNA vaccine expressing the wild-type Cap and the non-ultrasonic treated PCV2 DNA vaccine in mice, and protect the mice from PCV2 infection and lung lesions. The results indicate the new PCV2 DNA vaccine expressing the gC1qR binding site mutant Cap has a certain development value, and provide new insight into the development of novel PCV2 vaccines.
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Affiliation(s)
- Qian Du
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China,Engineering Research Center of Efficient New Vaccines for Animals, Ministry of Education, Xianyang, China
| | - Tengfei Shi
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China,Engineering Research Center of Efficient New Vaccines for Animals, Ministry of Education, Xianyang, China
| | - Huaxin Wang
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China,Engineering Research Center of Efficient New Vaccines for Animals, Ministry of Education, Xianyang, China
| | - Changlei Zhu
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China,Engineering Research Center of Efficient New Vaccines for Animals, Ministry of Education, Xianyang, China
| | - Nan Yang
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China,Engineering Research Center of Efficient New Vaccines for Animals, Ministry of Education, Xianyang, China
| | - Dewen Tong
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China,Engineering Research Center of Efficient New Vaccines for Animals, Ministry of Education, Xianyang, China,*Correspondence: Dewen Tong,
| | - Yong Huang
- College of Veterinary Medicine, Northwest A&F University, Xianyang, China,Engineering Research Center of Efficient New Vaccines for Animals, Ministry of Education, Xianyang, China,Yong Huang,
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Wu K, Hu W, Zhou B, Li B, Li X, Yan Q, Chen W, Li Y, Ding H, Zhao M, Fan S, Yi L, Chen J. Immunogenicity and Immunoprotection of PCV2 Virus-like Particles Incorporating Dominant T and B Cell Antigenic Epitopes Paired with CD154 Molecules in Piglets and Mice. Int J Mol Sci 2022; 23:ijms232214126. [PMID: 36430608 PMCID: PMC9694800 DOI: 10.3390/ijms232214126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/08/2022] [Accepted: 11/14/2022] [Indexed: 11/18/2022] Open
Abstract
Porcine circovirus type 2 (PCV2) is capable of causing porcine circovirus-associated disease (PCVAD) and is one of the major threats to the global pig industry. The nucleocapsid protein Cap encoded by the PCV2 ORF2 gene is an ideal antigen for the development of PCV2 subunit vaccines, and its N-terminal nuclear localization sequence (NLS) structural domain is essential for the formation of self-assembling VLPs. In the present study, we systematically expressed and characterized full-length PCV2 Cap proteins fused to dominant T and B cell antigenic epitopes and porcine-derived CD154 molecules using baculovirus and found that the Cap proteins fusing epitopes were still capable of forming virus-like particles (VLPs). Both piglet and mice experiments showed that the Cap proteins fusing epitopes or paired with the molecular adjuvant CD154 were able to induce higher levels of humoral and cellular responses, particularly the secretion of PCV2-specific IFN-γ and IL-4. In addition, vaccination significantly reduced clinical signs and the viral load of PCV2 in the blood and tissues of challenged piglets. The results of the study provide new ideas for the development of a more efficient, safe and broad-spectrum next-generation PCV2 subunit vaccine.
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Affiliation(s)
- Keke Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Wenshuo Hu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Bolun Zhou
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Bingke Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Xiaowen Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Quanhui Yan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Wenxian Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Yuwan Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Hongxing Ding
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Mingqiu Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Shuangqi Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Lin Yi
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Jinding Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Correspondence: ; Tel.: +86-20-85288017
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The gC1qR Binding Site Mutant PCV2 Is a Potential Vaccine Strain That Does Not Impair Memory CD4 + T-Cell Generation by Vaccines. J Virol 2022; 96:e0095922. [PMID: 36121300 PMCID: PMC9555195 DOI: 10.1128/jvi.00959-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PCV2 has been reported to reduce the protective effects of various vaccines on immunized pigs. Our previous studies showed that the interaction of Cap and host protein gC1qR mediated the PCV2 infection-induced suppression of immune response. Thus, we wondered whether the gC1qR binding site mutant PCV2RmA could be a vaccine strain and whether this mutant PCV2RmA impairs other vaccines. Herein, we showed that PCV2 infection reduced the classic swine fever virus (CSFV) vaccine-induced generation of memory CD4+ T cells through the interaction of Cap with gC1qR. PCV2RmA can effectively induce the production of PCV2-specific antibodies, neutralizing antibodies, and peripheral blood lymphocyte proliferation in piglets at the same levels as the commercial inactivated PCV2 vaccine. The PCV2RmA-induced anti-PCV2 immune responses could eliminate the serum virus and would not lead to pathological lesions like wild-type PCV2. Moreover, compared to the commercial inactivated PCV2 vaccine, PCV2RmA is capable of inducing more durable protective immunity against PCV2 that induced production of PCV2-specific antibodies and neutralizing antibodies for a longer time via stronger induction of memory CD4+ T cells. Importantly, PCV2RmA infection did not impair the CSFV vaccine-induced generation of memory CD4+ T cells. Collectively, our findings showed that PCV2 infection impairs memory CD4+ T-cell generation to affect vaccination and provide evidence for the use of PCV2RmA as an efficient vaccine to prevent PCV2 infection. IMPORTANCE PCV2 is one of the costliest pathogens in pigs worldwide. Usage of PCV2 vaccines can prevent the PCV2 infection-induced clinical syndromes but not the viral spread. Our previous work found that PCV2 infection suppresses the host type I interferon innate immune response and CD4+ T-cell-mediated Th1 immune response through the interaction of Cap with host gC1qR. Here, we showed that the gC1qR binding site mutant PCV2RmA could effectively induce anti-PCV2 immunity and provide more durable protective immunity against wild-type PCV2 infection in pigs. PCV2RmA would not impair the generation of memory CD4+ T cells induced by classic swine fever virus (CSFV) vaccines as wild-type PCV2 did. Therefore, PCV2RmA can serve as a potential vaccine strain to better protect pigs against PCV2 infection.
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10
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Guo J, Hou L, Zhou J, Wang D, Cui Y, Feng X, Liu J. Porcine Circovirus Type 2 Vaccines: Commercial Application and Research Advances. Viruses 2022; 14:2005. [PMID: 36146809 PMCID: PMC9504358 DOI: 10.3390/v14092005] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/06/2022] [Accepted: 09/07/2022] [Indexed: 11/16/2022] Open
Abstract
Porcine circovirus type 2 (PCV2) infection can lead to porcine circovirus-associated disease (PCVAD), causing great economic losses to the global swine industry. Conventional vaccination programs are a major measure in the prevention and control of this disease. Currently, there are 5 commercially available PCV2 vaccines in the international market and 10 kinds commercially available PCV2 vaccines in the Chinese market that confer good efficacy against this virus by alleviating clinicopathological manifestations and enhancing growth performance in pigs. In addition, diverse experimental PCV2 vaccines with protective efficiency have been developed, including attenuated chimeric, nucleic acid, subunit, multivalent, and viral-vectored vaccines. These experimental vaccines have been shown to be relatively effective in improving the efficiency of pig production and simplifying prevention procedures. Adjuvants can be used to promote vaccines with higher protective immunity. Herein, we review the application of multiple commercial vaccines over the years and research advances in experimental vaccines, which provide the possibility for the development of superior vaccines to successfully prevent and control PCV2 infection in the future.
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Affiliation(s)
- Jinshuo Guo
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225012, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225012, China
| | - Lei Hou
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225012, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225012, China
| | - Jianwei Zhou
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225012, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225012, China
| | - Dedong Wang
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225012, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225012, China
| | - Yongqiu Cui
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225012, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225012, China
| | - Xufei Feng
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225012, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225012, China
| | - Jue Liu
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou 225012, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225012, China
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11
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Systematic review of animal-based indicators to measure thermal, social, and immune-related stress in pigs. PLoS One 2022; 17:e0266524. [PMID: 35511825 PMCID: PMC9070874 DOI: 10.1371/journal.pone.0266524] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 03/22/2022] [Indexed: 11/19/2022] Open
Abstract
The intense nature of pig production has increased the animals’ exposure to stressful conditions, which may be detrimental to their welfare and productivity. Some of the most common sources of stress in pigs are extreme thermal conditions (thermal stress), density and mixing during housing (social stress), or exposure to pathogens and other microorganisms that may challenge their immune system (immune-related stress). The stress response can be monitored based on the animals’ coping mechanisms, as a result of specific environmental, social, and health conditions. These animal-based indicators may support decision making to maintain animal welfare and productivity. The present study aimed to systematically review animal-based indicators of social, thermal, and immune-related stresses in farmed pigs, and the methods used to monitor them. Peer-reviewed scientific literature related to pig production was collected using three online search engines: ScienceDirect, Scopus, and PubMed. The manuscripts selected were grouped based on the indicators measured during the study. According to our results, body temperature measured with a rectal thermometer was the most commonly utilized method for the evaluation of thermal stress in pigs (87.62%), as described in 144 studies. Of the 197 studies that evaluated social stress, aggressive behavior was the most frequently-used indicator (81.81%). Of the 535 publications examined regarding immune-related stress, cytokine concentration in blood samples was the most widely used indicator (80.1%). Information about the methods used to measure animal-based indicators is discussed in terms of validity, reliability, and feasibility. Additionally, the introduction and wide spreading of alternative, less invasive methods with which to measure animal-based indicators, such as cortisol in saliva, skin temperature and respiratory rate via infrared thermography, and various animal welfare threats via vocalization analysis are highlighted. The information reviewed was used to discuss the feasible and most reliable methods with which to monitor the impact of relevant stressors commonly presented by intense production systems on the welfare of farmed pigs.
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Jia Y, Zhu Q, Xu T, Chen X, Li H, Ma M, Zhang Y, He Z, Chen H. Detection and genetic characteristics of porcine circovirus type 2 and 3 in Henan province of China. Mol Cell Probes 2022; 61:101790. [PMID: 35051595 DOI: 10.1016/j.mcp.2022.101790] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 01/02/2022] [Accepted: 01/11/2022] [Indexed: 11/26/2022]
Abstract
PCV2 is one of the most economically important viral agents in swine worldwide. Recently, PCV3 has been frequently reported, and the co-infection of PCV2 and PCV3 is common in China. In order to explore the distribution, epidemiology and genetic diversity of PCV2 and PCV3, a total of 1,760 clinical tissue samples were randomly collected from 18 different regions in Henan province of China from October 2018 to September 2019 and screened for the presence of PCV2 and PCV3 by a duplex real-time PCR assay. The results showed that the positive rates of PCV2 and PCV3 were 72.90% and 5.17% respectively, and the co-infection rate of the two viruses was 3.64%. PCV2 and PCV3 are prevalent all year round. The prevalence of PCV2 in diseased pigs was 83.98%, higher than that in slaughterhouse pigs, while the prevalence of PCV3 in diseased pigs was 2.16%, slightly lower than that in slaughterhouse pigs. Furthermore, the complete genomes of 14 PCV2 and 3 PCV3 strains were obtained, among which 1 belonged to PCV2a, 5 belonged to PCV2b and 8 belonged to PCV2d. A new variant strain (XX2) might escape the host immune system. The phylogenetic analysis of PCV3 showed high nucleotide identity (>98%) between sequences obtained in this study and reference sequences. The results of this study might enrich the epidemiological data of PCV2 and PCV3 in Henan province and provide reference information for the comprehensive prevention and control of PCVAD.
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Affiliation(s)
- Yunfei Jia
- College of Economics and Management, Henan Agricultural University, Zhengzhou, 450002, Henan Province, People's Republic of China
| | - Qianlei Zhu
- Henan Center for Animal Disease Control and Prevention, Zhengzhou, Henan, 450002, China
| | - Tong Xu
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, Henan Province, People's Republic of China
| | - Ximeng Chen
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, Henan Province, People's Republic of China
| | - Hongxuan Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, Henan Province, People's Republic of China
| | - Mengyao Ma
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, Henan Province, People's Republic of China
| | - Yibei Zhang
- College of Economics and Management, Henan Agricultural University, Zhengzhou, 450002, Henan Province, People's Republic of China
| | - Zejun He
- College of Economics and Management, Henan Agricultural University, Zhengzhou, 450002, Henan Province, People's Republic of China.
| | - Hongying Chen
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450002, Henan Province, People's Republic of China.
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13
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Luo Q, Ahmed W, Dai Y, Mohsin A, Hang H, Zhuang Y, Guo M. Evaluation of a Virus-like Nanoparticle Porcine Circovirus Type-2 (PCV2) Capsid Protein Fused with the Pig Immunoglobulin Fc Fragment as a Novel Vaccine Candidate against PCV2 in Mice. Vaccines (Basel) 2021; 9:1128. [PMID: 34696236 PMCID: PMC8540293 DOI: 10.3390/vaccines9101128] [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: 07/12/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 11/16/2022] Open
Abstract
Porcine circovirus Type 2 (PCV2) is a primary etiological pathogen of post-weaning multi-systemic wasting syndrome (PMWS). The capsid protein of PCV2 is the crucial immunogenic protein which can induce antibody generation and immune responses. However, there is still a lack of efficient PCV2 vaccines with high immunogenicity. In the current study, we developed a novel engineered PCV2 capsid (∆1-41aa)-pFc fusion protein (PCFP), which comprised a truncated capsid protein of PCV2 and a porcine IgG Fc fragment, fused to the capsid protein of PCV2 at the C-terminus. We found that this novel fusion protein could auto-assemble into virus-like nanoparticles with an estimated mean diameter of 22.6 nm, characterized by transmission electron microscopy. Immunization of BALB/c mice with this fusion protein significantly increased the production levels of anti-PCV2-capsid protein antibody in serum. Besides, the virus-like nanoparticles, PCFP was demonstrated to induce efficient cellular immune responses in mice, as evident by the high specific T cell reactivity to the PCFP fusion protein and the high production of the immune cytokines IFN-γ and IL-10 in an ex vivo re-stimulation system. Collectively, these findings demonstrate that the PCV2 truncated capsid subunit Fc-fusion protein can induce both cellular and humoral immune responses, and it displays great application potential.
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Affiliation(s)
| | | | | | | | | | | | - Meijin Guo
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; (Q.L.); (W.A.); (Y.D.); (A.M.); (H.H.); (Y.Z.)
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14
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Li S, Wang B, Jiang S, Lan X, Qiao Y, Nie J, Yin Y, Shi Y, Kong W, Shan Y. Expression and evaluation of porcine circovirus type 2 capsid protein mediated by recombinant adeno-associated virus 8. J Vet Sci 2021; 22:e8. [PMID: 33522160 PMCID: PMC7850785 DOI: 10.4142/jvs.2021.22.e8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/18/2020] [Accepted: 11/29/2020] [Indexed: 11/20/2022] Open
Abstract
Background Porcine circovirus type 2 (PCV2) is an important infectious pathogen implicated in porcine circovirus-associated diseases (PCVAD), which has caused significant economic losses in the pig industry worldwide. Objectives A suitable viral vector-mediated gene transfer platform for the expression of the capsid protein (Cap) is an attractive strategy. Methods In the present study, a recombinant adeno-associated virus 8 (rAAV8) vector was constructed to encode Cap (Cap-rAAV) in vitro and in vivo after gene transfer. Results The obtained results showed that Cap could be expressed in HEK293T cells and BABL/c mice. The results of lymphocytes proliferative, as well as immunoglobulin G (IgG) 2a and interferon-γ showed strong cellular immune responses induced by Cap-rAAV. The enzyme-linked immunosorbent assay titers obtained and the IgG1 and interleukin-4 levels showed that humoral immune responses were also induced by Cap-rAAV. Altogether, these results demonstrated that the rAAV8 vaccine Cap-rAAV can induce strong cellular and humoral immune responses, indicating a potential rAAV8 vaccine against PCV2. Conclusions The injection of rAAV8 encoding PCV2 Cap genes into muscle tissue can ensure long-term, continuous, and systemic expression.
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Affiliation(s)
- Shuang Li
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Bo Wang
- School of Chemistry and Life Science, Changchun University of Technology, Changchun 130012, China
| | - Shun Jiang
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Xiaohui Lan
- The Second Hospital of Jilin University, Changchun 130012, China
| | - Yongbo Qiao
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Jiaojiao Nie
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Yuhe Yin
- School of Chemistry and Life Science, Changchun University of Technology, Changchun 130012, China
| | - Yuhua Shi
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China.
| | - Wei Kong
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China.,Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, China
| | - Yaming Shan
- National Engineering Laboratory for AIDS Vaccine, School of Life Sciences, Jilin University, Changchun 130012, China.,Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, China.
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15
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Chen YY, Yang WC, Chang YK, Wang CY, Huang WR, Li JY, Chuang KP, Wu HY, Chang CD, Nielsen BL, Liu HJ. Construction of polycistronic baculovirus surface display vectors to express the PCV2 Cap(d41) protein and analysis of its immunogenicity in mice and swine. Vet Res 2020; 51:112. [PMID: 32907618 PMCID: PMC7487469 DOI: 10.1186/s13567-020-00836-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 08/27/2020] [Indexed: 11/22/2022] Open
Abstract
To increase expression levels of the PCV2 Cap(d41) protein, novel baculovirus surface display vectors with multiple expression cassettes were constructed to create recombinant baculoviruses BacSC-Cap(d41), BacDD-2Cap(d41), BacDD-3Cap(d41), and BacDD-4Cap(d41). Our results reveal that the recombinant baculovirus BacDD-4Cap(d41) was able to express the highest levels of Cap(d41) protein. Optimum conditions for expressing the PCV2 Cap(d41) protein were determined, and our results show that 107 of Sf-9 infected with the recombinant baculovirus BacDD-4Cap(d41) at an MOI of 5 for 3 days showed the highest level of protein expression. Mice immunized with the 4Cap(d41) vaccine which was prepared from the recombinant baculovirus-infected cells (107) elicited higher ELISA titers compared to the Cap (d41) vaccine. The 4Cap(d41) vaccine could elicit anti-PCV2 neutralizing antibodies and IFN-γ in mice, as confirmed by virus neutralization test and IFN-γ ELISA. Moreover, the swine lymphocyte proliferative responses indicated that the 4Cap(d41) vaccine was able to induce a clear cellular immune response. Flow cytometry analysis showed that the percentage of CD4+ T cells and CD4+/CD8+ ratio was increased significantly in SPF pigs immunized with the 4Cap(d41) vaccine. Importantly, the 4Cap(d41) vaccine induced an IFN-γ response, further confirming that its effect is through cellular immunity in SPF pigs. An in vivo challenge study revealed that the 4Cap(d41) and the commercial vaccine groups significantly reduce the viral load of vaccinated pigs as compared with the CE negative control group. Taken together, we have successfully developed a 4Cap(d41) vaccine that may be a potential subunit vaccine for preventing the disease associated with PCV2 infections.
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Affiliation(s)
- Ya-Yi Chen
- Department of Stomatology, Tung's Taichung MetroHarbor Hospital, Taichung, Taiwan
- Medical Biotechnology, National Chung Hsing University, Taichung, 402, Taiwan
| | - Wei-Chen Yang
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 402, Taiwan
| | - Yu-Kang Chang
- Department of Medical Research, Tung's Taichung MetroHarbor Hospital, Taichung, Taiwan
- Department of Nursing, Jen-Teh Junior College of Medicine and Management, Hou-Long, Taiwan
| | - Chi-Young Wang
- Department of Veterinary Medicine, National Chung Hsing University, Taichung, 402, Taiwan
| | - Wei-Ru Huang
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 402, Taiwan
- The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, 402, Taiwan
| | - Jyun-Yi Li
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 402, Taiwan
- The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, 402, Taiwan
| | - Kuo-Pin Chuang
- Graduate Institute of Animal Vaccine Technology, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan
| | - Hung-Yi Wu
- Department of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan
| | - Ching-Dong Chang
- Department of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung, 912, Taiwan
| | - Brent L Nielsen
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, USA
| | - Hung-Jen Liu
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 402, Taiwan.
- The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, 402, Taiwan.
- Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung, 402, Taiwan.
- Translational Medicine, National Chung Hsing University, Taichung, 402, Taiwan.
- Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan.
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16
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Jiang Z, Wu J, Jiang M, Xie Y, Bu W, Liu C, Zhang G, Luo M. A Novel Technique for Constructing Infectious Cloning of Type 3 Porcine Circovirus. Front Microbiol 2020; 11:1067. [PMID: 32582064 PMCID: PMC7296095 DOI: 10.3389/fmicb.2020.01067] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 04/29/2020] [Indexed: 11/17/2022] Open
Abstract
Porcine circovirus type 3 (PCV3), which currently lacks effective preventive measures, has caused tremendous economic losses to the pig husbandry. Obtaining the strain of PCV3 is the key to preparing related vaccines and developing corresponding antiviral drugs. In this study, according to the linear sequence of PCV3 DNA published on GenBank, the sequence was rearranged with SnapGene gene-editing software, and after rearrangement, the HindIII restriction endonuclease site was added to the end of the linear DNA, so that both ends have the same restriction endonuclease site. On this basis, the rearranged linear DNA is obtained by gene synthesis, PCR amplification, DNA purification, etc., and is digested and connected in vitro to obtain cyclized DNA. PCV3 infectious clones were obtained by transfecting 3D4/21 cell lines. The obtained PCV3 was identified by PCR, Western blotting, and indirect immunofluorescence tests. The results showed that this study successfully obtained the strain of PCV3 in vitro. To further evaluate the pathogenicity of the obtained PCV3 infectious clones, this study established an animal model of Kunming mice infected with PCV3. The results of RT-PCR, Western blotting and immunohistochemistry showed that PCV3 can infect myocardium and alveoli of Kunming mice, but no PCV3 was detected in other tissues. The above studies indicate that PCV3 circular DNA can be used to construct PCV3 infectious clones. This research will provide a new method for the construction of circular DNA viruses and lay the foundation for the research and pathogenesis of PCV3 vaccine.
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Affiliation(s)
- Zaixue Jiang
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Jiajun Wu
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Mei Jiang
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Yilun Xie
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Wandi Bu
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Canbin Liu
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Guihong Zhang
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
| | - Manlin Luo
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
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17
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Molecular epidemiology and genetic variation analyses of porcine circovirus type 2 isolated from Yunnan Province in China from 2016-2019. BMC Vet Res 2020; 16:96. [PMID: 32293447 PMCID: PMC7087357 DOI: 10.1186/s12917-020-02304-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 03/03/2020] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Porcine circovirus type 2 (PCV2) is the causative agent of porcine circovirus-associated disease (PCVAD). Its prevalence in swine herds was first reported in China in 2000. PCV2 infection causes immunosuppression that leads to multiple diseases, causing serious economic problems for the swine industry in China. Since information on the genetic variation of PCV2 in Yunnan province is limited, this study aims to investigate the molecular epidemiological and evolutionary characteristics of PCV2 from 2016 to 2019. METHODS A total of 279 clinical samples were collected from different regions of Yunnan between 2016 to 2019, and PCV2 was detected by PCR. We then amplified full genomes from the positive samples, and the sequences were analysed for homology and genetic evolution. RESULTS Overall, 60.93% (170/279) of the screened swine herd samples were positive for PCV2. We sequenced 15 Yunnan province PCV2 strains from positive samples. Analyses of the complete genomes and Cap genes led to the classification of the 15 Yunnan PCV2 strains into PCV2a (2 of 15), PCV2b (1of 15) and PCV2d (12 of 15). All strains shared 94.3-99.9% of their identities with the nucleotide sequences of complete genomes in this study and shared 94.2-99.9% identity with the reference sequences. All strains share 89.4-100% and 86.8-100% of their identities with the nucleotide and amino acid (aa) sequences of Cap, respectively. CONCLUSIONS The results of this study provide evidence that PCV2a, PCV2b and PCV2d genotypes coexisted in Yunnan Province from 2016 to 2019, and the priority prevalence genotype was PCV2d. The data provide evidence for the increased genetic diversity and insights into the molecular epidemiology of PCV2. This study also provides basic data for the Yunnan province PCV2 molecular epidemiological survey and accumulates effective materials for the development of PCV2 vaccines.
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18
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Liu X, Ouyang T, Ma T, Ouyang H, Pang D, Ren L. Immunogenicity evaluation of inactivated virus and purified proteins of porcine circovirus type 2 in mice. BMC Vet Res 2018; 14:137. [PMID: 29685143 PMCID: PMC5913788 DOI: 10.1186/s12917-018-1461-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 04/16/2018] [Indexed: 01/08/2023] Open
Abstract
Background Vaccination is considered as an effective and economical way to against PCV2 infection. However, some of commercial available vaccines are based on inactivated viruses, while the others are based on purified protein of PCV2. In the present study, we aimed to compare the immunogenicity of inactivated virus and purified proteins of porcine circovirus type 2 in mice. Results The results showed that positive antiserum titers were significantly increased after second, third and fourth immunization using inactivated PCV2 or purified proteins as coating antigen. Moreover, the inactivated PCV2 induced significantly higher levels of PCV2-specific antibodies than that of PCV2 subunit proteins. After PCV2 wild strain challenged, the average daily gain was comparable with that of mice in the mock group, and the sera from both inactivated PCV2-immunized animals and subunit protein Cap+ORF3 + Rep immunized animals had significantly higher neutralizing antibody titers than that of the PBS group. As expected, the neutralizing antibody in the inactivated PCV2 group was significantly higher than that of the subunit protein group. These results indicated that positive antiserum induced by the inactivated PCV2 had a better reactivity and specificity than that of the positive antiserum induced by the purified proteins. Conclusions The results in the present study demonstrated inactivated PCV2 is more effective than PCV2 subunit proteins in stimulating immune response to against PCV2 infection.
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Affiliation(s)
- Xiaohui Liu
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Sciences, Jilin University, Changchun, Jilin, 130062, China
| | - Ting Ouyang
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Sciences, Jilin University, Changchun, Jilin, 130062, China
| | - Teng Ma
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Sciences, Jilin University, Changchun, Jilin, 130062, China
| | - Hongsheng Ouyang
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Sciences, Jilin University, Changchun, Jilin, 130062, China
| | - Daxin Pang
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Sciences, Jilin University, Changchun, Jilin, 130062, China
| | - Linzhu Ren
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, College of Animal Sciences, Jilin University, Changchun, Jilin, 130062, China.
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