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Zhao M, Zhang P, Zhang X, Luo S, Yuan Z, Huang Y, Wang G, Xiang H, Huang Y, Jin Y, Chen J, Wang X. Immune Protection Gap Between Porcine Reproductive and Respiratory Syndrome Subunit Vaccine (N Protein) and Live Vaccine. Vaccines (Basel) 2025; 13:441. [PMID: 40432053 DOI: 10.3390/vaccines13050441] [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: 02/24/2025] [Revised: 04/18/2025] [Accepted: 04/21/2025] [Indexed: 05/29/2025] Open
Abstract
Objectives: To evaluate the immunoprotective effect of a PRRSV N protein subunit vaccine on piglets using a live PRRSV vaccine as a control. Methods: The HEK-293T eukaryotic expression system was used to produce PRRSV N protein, and then PRRSV N protein was immunized with a commercial live PRRS vaccine. The immunoprotective effect of the PRRSV N protein subunit vaccine on piglets was evaluated by detecting the antibody level in the immunized piglets, and the clinical symptoms, pathological changes, and survival rate of the immunized piglets. Results: At 21 and 28 days after immunization, the serum N protein-specific antibody levels of piglets in the live PRRSV vaccine group were higher than those in the N protein group. After PRRSV infection, piglets in the N protein group and the DMEM group showed more severe clinical symptoms such as respiratory distress, loss of appetite, skin redness, and diarrhea than those in the live vaccine group. The rectal temperature of piglets in the live vaccine group remained below 40 °C, and only one piglet died on day 11 post-infection; in the PRRSV N protein group, the rectal temperature of some piglets exceeded 41 °C, and four piglets died on days 9, 11, 14, and 20 post-infection. In addition, pathologic damage to organs such as lungs, liver, lymph nodes, spleen, and kidneys was more severe in the N protein group than in the live vaccine group. Furthermore, histopathology and immunohistochemistry showed more pronounced organ damage (lungs, liver, lymph nodes, spleen, and kidneys) and higher viral loads in the N protein group compared to the live vaccine group. Conclusions: The PRRS subunit vaccine (N protein) expressed in the HEK-293T eukaryotic system did not protect piglets from heterologous PRRSV infection compared with the PRRS live vaccine.
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Grants
- (2023A1111110001 and 2021B1212050021), (2024CXTD15),(2023QZ-NK13, ZQQZ-55), (2023B04J0137 and 2023E04J1256), (2021YFD1801400, 2021YFD1801404), (2023B1212060040). This work was supported by the Planning Funds for Science and Technology of Guangdong Province, Modern Agricultural Research System Innovation Team Project of Guangdong Province , State Key Laboratory of Swine and Poultry Breeding Industry , the Scientifi
- (2023A1111110001 and 2021B1212050021), (2024CXTD15),(2023QZ-NK13, ZQQZ-55), (2023B04J0137 and 2023E04J1256), (2021YFD1801400, 2021YFD1801404), (2023B1212060040). Planning Funds for Science and Technology of Guangdong Province . Modern Agricultural Research System Innovation Team Project of Guangdong Province. State Key Laboratory of Swine and Poultry Breeding Industry . the Scientific and Technological Plan Proje
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Affiliation(s)
- Mengpo Zhao
- Guangdong Province Key Laboratory of Livestock Disease Prevention, Guangdong Provincial Observation and Research Station for Animal Disease, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China
| | - Pian Zhang
- Guangdong Province Key Laboratory of Livestock Disease Prevention, Guangdong Provincial Observation and Research Station for Animal Disease, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
| | - Xiaoxiao Zhang
- Guangdong Province Key Laboratory of Livestock Disease Prevention, Guangdong Provincial Observation and Research Station for Animal Disease, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
| | - Shengjun Luo
- Guangdong Province Key Laboratory of Livestock Disease Prevention, Guangdong Provincial Observation and Research Station for Animal Disease, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
| | - Ziguo Yuan
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China
| | - Yanju Huang
- Guangdong Province Key Laboratory of Livestock Disease Prevention, Guangdong Provincial Observation and Research Station for Animal Disease, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China
| | - Gang Wang
- Guangdong Province Key Laboratory of Livestock Disease Prevention, Guangdong Provincial Observation and Research Station for Animal Disease, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
| | - Hua Xiang
- Guangdong Province Key Laboratory of Livestock Disease Prevention, Guangdong Provincial Observation and Research Station for Animal Disease, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
| | - Yuan Huang
- Guangdong Province Key Laboratory of Livestock Disease Prevention, Guangdong Provincial Observation and Research Station for Animal Disease, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
| | - Yuzhu Jin
- Jiaozuo City Product Quality Inspection and Testing Center, Jiaozuo 454000, China
| | - Jing Chen
- Guangdong Province Key Laboratory of Livestock Disease Prevention, Guangdong Provincial Observation and Research Station for Animal Disease, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
| | - Xiaohu Wang
- Guangdong Province Key Laboratory of Livestock Disease Prevention, Guangdong Provincial Observation and Research Station for Animal Disease, Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Baishigang, Wushan Street, Tianhe District, Guangzhou 510640, China
- College of Veterinary Medicine, South China Agricultural University, No. 483 Wushan Road, Tianhe District, Guangzhou 510642, China
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Chang X, Ma J, Zhou Y, Xiao S, Xiao X, Fang L. Development of a Ferritin Protein Nanoparticle Vaccine with PRRSV GP5 Protein. Viruses 2024; 16:991. [PMID: 38932282 PMCID: PMC11209462 DOI: 10.3390/v16060991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 06/10/2024] [Accepted: 06/13/2024] [Indexed: 06/28/2024] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) presents a significant threat to the global swine industry. The development of highly effective subunit nanovaccines is a promising strategy for preventing PRRSV variant infections. In this study, two different types of ferritin (Ft) nanovaccines targeting the major glycoprotein GP5, named GP5m-Ft and (Bp-IVp)3-Ft, were constructed and evaluated as vaccine candidates for PRRSV. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) demonstrated that both purified GP5m-Ft and (Bp-IVp)3-Ft proteins could self-assemble into nanospheres. A comparison of the immunogenicity of GP5m-Ft and (Bp-IVp)3-Ft with an inactivated PRRSV vaccine in BALB/c mice revealed that mice immunized with GP5m-Ft exhibited the highest ELISA antibody levels, neutralizing antibody titers, the lymphocyte proliferation index, and IFN-γ levels. Furthermore, vaccination with the GP5m-Ft nanoparticle effectively protected piglets against a highly pathogenic PRRSV challenge. These findings suggest that GP5m-Ft is a promising vaccine candidate for controlling PRRS.
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Affiliation(s)
- Xinjian Chang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (X.C.); (J.M.); (Y.Z.); (S.X.)
- The Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Jun Ma
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (X.C.); (J.M.); (Y.Z.); (S.X.)
- The Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Yanrong Zhou
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (X.C.); (J.M.); (Y.Z.); (S.X.)
- The Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Shaobo Xiao
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (X.C.); (J.M.); (Y.Z.); (S.X.)
- The Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Xun Xiao
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (X.C.); (J.M.); (Y.Z.); (S.X.)
- The Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Liurong Fang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (X.C.); (J.M.); (Y.Z.); (S.X.)
- The Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
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3
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Research Progress on Glycoprotein 5 of Porcine Reproductive and Respiratory Syndrome Virus. Animals (Basel) 2023; 13:ani13050813. [PMID: 36899670 PMCID: PMC10000246 DOI: 10.3390/ani13050813] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 02/14/2023] [Accepted: 02/20/2023] [Indexed: 02/26/2023] Open
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is an acute, febrile, and highly contagious disease caused by the porcine reproductive and respiratory syndrome virus (PRRSV). Glycoprotein 5 (GP5) is a glycosylated envelope protein encoded by the PRRSV ORF5, which has good immunogenicity and can induce the body to produce neutralizing antibodies. Therefore, study of GP5 protein is of great significance in the diagnosis, prevention, and control of PRRSV and the development of new vaccines. We reviewed GP5 protein genetic variation, immune function, interaction with viral protein and host proteins, induction of cell apoptosis, and stimulation of neutralizing antibodies. GP5 protein's influence on virus replication and virulence, as well as its use as a target for viral detection and immunization are reviewed.
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4
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Fang K, Liu S, Li X, Chen H, Qian P. Epidemiological and Genetic Characteristics of Porcine Reproductive and Respiratory Syndrome Virus in South China Between 2017 and 2021. Front Vet Sci 2022; 9:853044. [PMID: 35464348 PMCID: PMC9024240 DOI: 10.3389/fvets.2022.853044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 03/21/2022] [Indexed: 11/26/2022] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) remains a major threat to the swine industry in China and has caused enormous losses every year. To monitor the epidemiological and genetic characteristics of PRRSV in South China, 6,795 clinical samples from diseased pigs were collected between 2017 and 2021, and 1,279 (18.82%) of them were positive for PRRSV by RT-PCR detecting the ORF5 gene. Phylogenetic analysis based on 479 ORF5 sequences revealed that a large proportion of them were highly-pathogenic PRRSVs (409, 85.39%) and PRRSV NADC30-like strains (66, 13.78%). Furthermore, 93.15% of these highly-pathogenic strains were found to be MLV-derived. We next recovered 11 PRRSV isolates from the positive samples and generated the whole genome sequences of them. Bioinformatic analysis showed that seven isolates were MLV-derived. Besides, six isolates were found to be recombinant strains. These eleven isolates contained different types of amino acid mutations in their GP5 and Nsp2 proteins compared to those of the PRRSVs with genome sequences publicly available in GenBank. Taken together, our findings contribute to understanding the prevalent status of PRRSV in South China and provide useful information for PRRS control especially the use of PRRSV MLV vaccines.
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Affiliation(s)
- Kui Fang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Shudan Liu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Xiangmin Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Huanchun Chen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
- Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture of the People's Republic of China, Wuhan, China
| | - Ping Qian
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
- Key Laboratory of Development of Veterinary Diagnostic Products, Ministry of Agriculture of the People's Republic of China, Wuhan, China
- *Correspondence: Ping Qian
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5
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Rajkhowa TK, Thanga L, Hauhnar L, Zodinpui D, Subbiah M. Molecular detection and characterization of highly pathogenic porcine reproductive and respiratory syndrome virus from a natural outbreak in wild pigs, Mizoram, India. Transbound Emerg Dis 2021; 69:e288-e298. [PMID: 34406700 DOI: 10.1111/tbed.14296] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 03/28/2021] [Accepted: 08/17/2021] [Indexed: 11/29/2022]
Abstract
This study reports for the first time a natural outbreak of highly pathogenic porcine reproductive and respiratory syndrome (HP-PRRS) caused by HP-PRRS virus (HP-PRRSV) in wild pigs characterized by sudden onset of depression, anorexia, respiratory distress, and high fever. The disease has caused severe haemorrhagic pneumonia, haemorrhagic lymphadenitis, enlarged spleen with areas of infarction, and petechial haemorrhages on the myocardium and on the surface of kidneys. HP-PRRSV was detected in representative tissue samples by reverse transcription-PCR, and the field strain was isolated in the MA104 cell line. The phylogenetic analyses based on the whole genome sequences and nucleotide sequences of open reading frame 5 (ORF5) gene showed close grouping with the subtype IV of lineage 8/8.7 of PRRSV II, which represents the HP-PRRSV strains that predominate in the pig population of China since 2010. The amino acid sequence analysis of the ORF5 gene revealed the replacement of leucine (L) at position 39 to isoleucine (I) in the primary neutralizing epitope. Among the four potential N glycosylation sites, the N34 was mutated and found to be restricted to only three N glycosylation sites. The present findings have indicated that HP-PRRSV can cause fatal outbreaks and may emerge as a major threat to the wild pig population.
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Affiliation(s)
- Tridib Kumar Rajkhowa
- Department of Veterinary Pathology, College of Veterinary Sciences & Animal Husbandry, Central Agricultural University, Aizawl, Mizoram, India
| | - Lalnun Thanga
- Department of Veterinary Pathology, College of Veterinary Sciences & Animal Husbandry, Central Agricultural University, Aizawl, Mizoram, India
| | - Lalthapui Hauhnar
- Department of Veterinary Pathology, College of Veterinary Sciences & Animal Husbandry, Central Agricultural University, Aizawl, Mizoram, India
| | - Doris Zodinpui
- Department of Veterinary Pathology, College of Veterinary Sciences & Animal Husbandry, Central Agricultural University, Aizawl, Mizoram, India
| | - Madhuri Subbiah
- National Institute of Animal Biotechnology, Hyderabad, Telangana, India
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6
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Charleston B, Graham SP. Recent advances in veterinary applications of structural vaccinology. Curr Opin Virol 2018; 29:33-38. [PMID: 29550741 PMCID: PMC5954236 DOI: 10.1016/j.coviro.2018.02.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 02/20/2018] [Accepted: 02/28/2018] [Indexed: 01/22/2023]
Abstract
The deployment of effective veterinary vaccines has had a major impact on improving food security and consequently human health. Effective vaccines were essential for the global eradication of Rinderpest and the control and eradication of foot-and-mouth disease in some regions of the world. Effective vaccines also underpin the development of modern intensive food production systems such as poultry and aquaculture. However, for some high consequence diseases there are still significant challenges to develop effective vaccines. There is a strong track record in veterinary medicine of early adoption of new technologies to produce vaccines. Here we provide examples of new technologies to interrogate B cell responses and using structural biology to improve antigens.
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Affiliation(s)
- Bryan Charleston
- The Pirbright Institute, Ash Road, Pirbright, Guildford GU24 0NF, Surrey, United Kingdom.
| | - Simon P Graham
- The Pirbright Institute, Ash Road, Pirbright, Guildford GU24 0NF, Surrey, United Kingdom
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7
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Chen XW, Li L, Yin M, Wang Q, Luo WT, Ma Y, Pu ZH, Zhou JL. Cloning and molecular characterization of the ORF5 gene from a PRRSV-SN strain from Southwest China. Microb Pathog 2017; 112:295-302. [PMID: 28970171 DOI: 10.1016/j.micpath.2017.09.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 08/23/2017] [Accepted: 09/11/2017] [Indexed: 11/17/2022]
Abstract
To monitor the genetic variation of PRRSV, the ORF5 gene of the PRRSV-SN strain found in Suining City, Sichuan Province, was cloned and sequenced. The results showed that the PRRSV-SN strain was a highly pathogenic PRRSV (HP-PRRSV) variant strain with the North American (NA) genotype. Homology analysis showed that the ORF5 gene of the PRRSV-SN isolate shared 89.4% (86.5%) nucleotide (amino acid) sequence similarity with the North American strain VR-2332, 98.8% (96%) similarity with JXA1, and 63.8% (57.7%) similarity with the European type representative strain Lelystad virus. Phylogenetic analysis showed that PRRSV-SN belongs to the NA genotype and has the same subtype as other highly pathogenic PRRSV strains. Amino acid sequence analysis showed that compared with the VR2332 strain, PRRSV-SN has different degrees of variation in the signal peptide, transmembrane region (TM), primary neutralizing epitope (PNE), non-neutral epitopes and N-glycosylation sites. Antigenicity analysis showed that the PRRSV-SN ORF5 gene products and JXA1 have similar antigenic characteristics, and the antigenic epitopes are mainly located in aa30-39, aa50-60, aa128-141, aa146-155 and aa161-183 regions. In contrast, the antigenic characteristics of PRRSV-SN are quite different from those of the VR2332 strain. The main differences were that the PRRSV-SN strain was significantly narrower than the VR2332 strain in the aa30-39 and the aa50-60 regions but was significantly wider in the aa136-141 region. The results of this study showed that the epidemic strains that cause PRRSV outbreaks in the farm are still mainly JXA1 variants, but due to the more frequent use of live vaccine immunizations, the genes of the PRRSV epidemic strain still show constant variation. Vaccination with live PRRSV should be reduced, and surveillance of PRRSV strains should be enhanced.
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Affiliation(s)
- Xi-Wen Chen
- Institute of Applied Animal Technology, Mianyang Normal University, Mianyang, Sichuan, 621000, China; Research Center of Ecological Agriculture and Animal Husbandry in Northwest Sichuan, Mianyang, Sichuan, 621000, China.
| | - Lian Li
- Institute of Applied Animal Technology, Mianyang Normal University, Mianyang, Sichuan, 621000, China; College of Life Science, Southwest Forestry University, Kunming, Yunnan, 650224, China
| | - Miao Yin
- Institute of Applied Animal Technology, Mianyang Normal University, Mianyang, Sichuan, 621000, China
| | - Qian Wang
- Institute of Applied Animal Technology, Mianyang Normal University, Mianyang, Sichuan, 621000, China; College of Life Science, Southwest Forestry University, Kunming, Yunnan, 650224, China
| | - Wen-Tao Luo
- Institute of Applied Animal Technology, Mianyang Normal University, Mianyang, Sichuan, 621000, China; College of Life Science, Southwest Forestry University, Kunming, Yunnan, 650224, China
| | - Ying Ma
- Institute of Applied Animal Technology, Mianyang Normal University, Mianyang, Sichuan, 621000, China; Research Center of Ecological Agriculture and Animal Husbandry in Northwest Sichuan, Mianyang, Sichuan, 621000, China
| | - Zhong-Hui Pu
- Institute of Applied Animal Technology, Mianyang Normal University, Mianyang, Sichuan, 621000, China; Research Center of Ecological Agriculture and Animal Husbandry in Northwest Sichuan, Mianyang, Sichuan, 621000, China
| | - Jie-Long Zhou
- College of Life Science, Southwest Forestry University, Kunming, Yunnan, 650224, China
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8
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A novel recombinant porcine reproductive and respiratory syndrome virus with significant variation in cell adaption and pathogenicity. Vet Microbiol 2017; 208:150-158. [PMID: 28888630 DOI: 10.1016/j.vetmic.2017.07.028] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 07/24/2017] [Accepted: 07/26/2017] [Indexed: 12/20/2022]
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) is an important pathogen that causes huge economic losses to the swine industry worldwide. In this study, a type 2 PRRSV strain was isolated from primary porcine alveolar macrophage cells and designated as GD1404. Interestingly, this strain was unable to grow in MARC-145 cells. Analysis of the full-length genome sequence revealed that strain GD1404 was an inter-subgenotype recombinant of strains QYYZ and JXA1. The C-terminus of the GP2 protein of strain GD1404 had an amino acid deletion. Also, the ORF5a protein had 51 codons, five more than most other highly pathogenic (HP-PRRSV) strains. Phylogenetic analysis based on ORF5 gene sequences showed that strain GD1404 and five others isolated in China formed a new subgenotype represented by strain QYYZ. Challenge experiments with piglets showed that the GD1404 and HP-PRRSV BB0907 strains caused similar rates of mortality and interstitial pneumonia. However, strain GD1404 infection resulted in lower viremia and viral loads in the lungs, as compared with strain BB0907. The results of this study provide evidence of the circulation of type 2 PRRSV QYYZ-like strains in China with variations in cell adaption and pathogenic abilities.
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9
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Yu L, Zhao P, Dong J, Liu Y, Zhang L, Liang P, Wang L, Song C. Genetic characterization of 11 porcine reproductive and respiratory syndrome virus isolates in South China from 2014 to 2015. Virol J 2017; 14:139. [PMID: 28738888 PMCID: PMC5525233 DOI: 10.1186/s12985-017-0807-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 07/14/2017] [Indexed: 12/03/2022] Open
Abstract
Background Porcine reproductive and respiratory syndrome (PRRS) has leaded to an enormous loss per year to the swine industry, its etiology porcine reproductive and respiratory syndrome virus (PRRSV) is a highly mutated virus in pigs. To fully understand the genetic characteristics of PRRSV genome in South China, this study collected the lung samples infected with PRRSV in Guangdong and Hainan province from 2014 to 2015 and tried to isolate the PRRSV. Finally, the complete genomes of isolated strains were sequenced and analyzed. Methods Virus isolation was performed in MARC-145 cells. The 13 fragments of PRRSV genome were amplified by RT-PCR and the complete PRRSV genome sequence was obtained by SeqMan program of DNASTAR7.0 software. Nucleotide and deduced amino acid (AA) sequences of NSP2 and ORF5 were aligned using the MegAlign program of DNASTAR7.0 software to determine sequence homology. A phylogenetic tree was constructed using MEGA5.2 software with the neighbor-joining method to analyze the evolutionary relationship. Results 11 PRRSV strains were isolated in South China from 2014 to 2015. All the isolated strains clustered into subgenotype V along with the HP-PRRSV representative strains JXA1, HuN4 and JXwn06. The subgenotype V was furtherly divided into two groups. AA sequence alignment analysis indicated that all the isolated strains had 1 AA deletion and 29 AA continuous deletion at position 481 and 533-561. Notably, GDHY strain had another 120 AA continuous deletion at position 629-748. All the isolated strains had an A137S mutation in the residue A137 of GP5 which was considered to differentiate vaccine strains. All the isolated strains had a L39I mutation in the primary neutralizing epitope (PNE) of GP5. Except GDHZ had a N34T mutation, all the other isolated strains had conserved N30, N44 and N51 glycosylation sites in the four potential N-glycosylation sites (N30, N34, N44 and N51) of GP5. Conclusions Our study showed that the prevalent strains in this region were highly pathogenic PRRS virus-like. Moreover, one new strain having another 120 amino acids continuous deletion except the discontinuous 30 (29+1) amino acids deletion in NSP2 region had emerged. Besides, the isolated strains had extensive amino acids substitutions in the putative signal, extravirion and intravirion regions of GP5. These results showed that PRRSV has undergone extensive variation in South China, providing some theoretical basis for researching effective vaccince to better controling the PRRSV in this area.
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Affiliation(s)
- Linyang Yu
- College of Animal Science & National Engineering Center for Swine Breeding Industry, South China Agriculture University, Guangzhou, 510642, China
| | - Pandeng Zhao
- College of Animal Science & National Engineering Center for Swine Breeding Industry, South China Agriculture University, Guangzhou, 510642, China.,Henan University of Animal Husbandry and Economy, Zhengzhou, 450046, China
| | - Jianguo Dong
- College of Animal Science & National Engineering Center for Swine Breeding Industry, South China Agriculture University, Guangzhou, 510642, China.,College of Animal Husbandry and Veterinary, Xinyang Agriculture and Forestry University, Xinyang, 464000, China
| | - Yanling Liu
- College of Animal Science & National Engineering Center for Swine Breeding Industry, South China Agriculture University, Guangzhou, 510642, China
| | - Leyi Zhang
- College of Animal Science & National Engineering Center for Swine Breeding Industry, South China Agriculture University, Guangzhou, 510642, China
| | - Pengshuai Liang
- College of Animal Science & National Engineering Center for Swine Breeding Industry, South China Agriculture University, Guangzhou, 510642, China
| | - Lei Wang
- College of Animal Science & National Engineering Center for Swine Breeding Industry, South China Agriculture University, Guangzhou, 510642, China
| | - Changxu Song
- College of Animal Science & National Engineering Center for Swine Breeding Industry, South China Agriculture University, Guangzhou, 510642, China.
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10
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Wang PP, Dong JG, Zhang LY, Liang PS, Liu YL, Wang L, Fan FH, Song CX. Sequence and Phylogenetic Analyses of the Nsp2 and ORF5 Genes of Porcine Reproductive and Respiratory Syndrome Virus in Boars from South China in 2015. Transbound Emerg Dis 2016; 64:1953-1964. [DOI: 10.1111/tbed.12594] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Indexed: 11/29/2022]
Affiliation(s)
- P. P. Wang
- College of Animal Science & National Engineering Center for Swine Breeding Industry; South China Agriculture University; Guangzhou China
| | - J. G. Dong
- College of Animal Science & National Engineering Center for Swine Breeding Industry; South China Agriculture University; Guangzhou China
- Xinyang Animal Disease Prevention and Control Engineering Research Center; Xinyang College of Agriculture and Forestry; Xinyang China
| | - L. Y. Zhang
- College of Animal Science & National Engineering Center for Swine Breeding Industry; South China Agriculture University; Guangzhou China
| | - P. S. Liang
- College of Animal Science & National Engineering Center for Swine Breeding Industry; South China Agriculture University; Guangzhou China
| | - Y. L. Liu
- College of Animal Science & National Engineering Center for Swine Breeding Industry; South China Agriculture University; Guangzhou China
| | - L. Wang
- College of Animal Science & National Engineering Center for Swine Breeding Industry; South China Agriculture University; Guangzhou China
| | - F. H. Fan
- Testing Center of Breeding Swine Quality of China Ministry of Agriculture; Guangzhou China
| | - C. X. Song
- College of Animal Science & National Engineering Center for Swine Breeding Industry; South China Agriculture University; Guangzhou China
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Pathogenicity and antigenicity of a novel NADC30-like strain of porcine reproductive and respiratory syndrome virus emerged in China. Vet Microbiol 2016; 197:93-101. [PMID: 27938690 DOI: 10.1016/j.vetmic.2016.11.010] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 11/11/2016] [Accepted: 11/12/2016] [Indexed: 01/14/2023]
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) has spread globally and caused huge economic loss. In recent years, a new kind of highly pathogenic NADC30-like strain has emerged in China. However, the pathogenicity and antigenicity of the virus are not well understood. In this study, PRRSV strain FJ1402 was isolated from piglets with clinical signs in Fujian Province in China in 2014. The complete genomic sequence analysis showed that it arose from recombination of North America NADC30 strain and highly pathogenic PRRSV (HP-PRRSV) in China. Experiment in piglets showed that FJ1402 had similar virulence to HP-PRRSV strain BB0907. The commercial PRRSV modified live vaccines TJM-F92 and R98 could partly provide protective efficacy against FJ1402 challenge in piglets. This should be helpful for preventing and controlling this disease in the future.
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Wang X, Wang Z, Xu H, Biao X, Yang Z. A single amino acid substitution alter antigenicity of Glycosylated protein 4 of HP-PRRSV. Virol J 2016; 13:129. [PMID: 27457087 PMCID: PMC4960902 DOI: 10.1186/s12985-016-0586-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 07/12/2016] [Indexed: 11/10/2022] Open
Abstract
Background Porcine reproductive and respiratory syndrome (PRRS) is an important pig endemic disease in pork-producing countries worldwide. The etiology, porcine reproductive and respiratory syndrome virus (PRRSV), is characterized by fast antigen variability. Glycosylated protein 4 (GP4) is a minor protein in PRRSV virion, but contributes to induce protective immune responses. However, the antigenic characterization of PRRSV GP4 and the role of the mutations in this protein in PRRSV evolution are not clear. Methods Peptides chip scanning and peptide based ELISA was used to analyze the antigenic characterization of HP-PRRSV GP4. A total of 142 peptides printed on a chip were used to reveal the antigen reaction characteristics of the HP-PRRSV. The reactions of these peptides with HP-PRRSV-specific pig serum were scanned and quantified using the software PepSlide® Analyzer by fluorescence intensity. The active reaction regions (AR) were identified based on the scanning results and then the amino acids (aa) sequences of AR(s) is aligned among PRRSV strains for further identify the key aa site(s) impact the antigenicity of the protein. Peptide based ELISA is then reacted with PRRSV positive sera derived from pig inoculated with different PRRSV strains for further analysis the role of specific amino acid in AR. Results The intensity plot was used to show the reactions of the peptides with PRRSV serum and it showed that enormously different response happened to various parts of GP4. The highest reaction intensity value reached 6401.5 against one peptide with the sequence DIKTNTTAASDFVVL. An AR from S29 to G56 was identified. Sequence alignment revealed various mutations in site 43 and possibly played an important role in this AR. Peptides ELISA reaction with sera from pigs inoculated with different PRRSV strain revealed that the change of aa in site 43 reduced the reaction of the peptide with PRRSV positive sera derived from pigs inoculated with the peptide related PRRSV strains. Conclusion In this study, one AR covering S29 to G56 was identified in GP4. The aa in site 43 play an important role in determining the antigenic character of GP4. The continual mutations (S → G → D → N) occurred in this site alter the antigenicity of PRRSV GP4. Electronic supplementary material The online version of this article (doi:10.1186/s12985-016-0586-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xinglong Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. .,Northwest A&F University, No. 3 Taicheng Road, 712100, Yangling, Shaanxi, China.
| | - Zhenbin Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Hongyu Xu
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Xiang Biao
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Zengqi Yang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. .,Northwest A&F University, No. 3 Taicheng Road, 712100, Yangling, Shaanxi, China.
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13
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Mokhtar H, Pedrera M, Frossard JP, Biffar L, Hammer SE, Kvisgaard LK, Larsen LE, Stewart GR, Somavarapu S, Steinbach F, Graham SP. The Non-structural Protein 5 and Matrix Protein Are Antigenic Targets of T Cell Immunity to Genotype 1 Porcine Reproductive and Respiratory Syndrome Viruses. Front Immunol 2016; 7:40. [PMID: 26909080 PMCID: PMC4755262 DOI: 10.3389/fimmu.2016.00040] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 01/26/2016] [Indexed: 01/01/2023] Open
Abstract
The porcine reproductive and respiratory syndrome virus (PRRSV) is the cause of one of the most economically important diseases affecting swine worldwide. Efforts to develop a next-generation vaccine have largely focused on envelope glycoproteins to target virus-neutralizing antibody responses. However, these approaches have failed to demonstrate the necessary efficacy to progress toward market. T cells are crucial to the control of many viruses through cytolysis and cytokine secretion. Since control of PRRSV infection is not dependent on the development of neutralizing antibodies, it has been proposed that T cell-mediated immunity plays a key role. Therefore, we hypothesized that conserved T cell antigens represent prime candidates for the development a novel PRRS vaccine. Antigens were identified by screening a proteome-wide synthetic peptide library with T cells from cohorts of pigs rendered immune by experimental infections with a closely related (subtype 1) or divergent (subtype 3) PRRSV-1 strain. Dominant T cell IFN-γ responses were directed against the non-structural protein 5 (NSP5), and to a lesser extent, the matrix (M) protein. The majority of NSP5-specific CD8 T cells and M-specific CD4 T cells expressed a putative effector memory phenotype and were polyfunctional as assessed by coexpression of TNF-α and mobilization of the cytotoxic degranulation marker CD107a. Both antigens were generally well conserved among strains of both PRRSV genotypes. Thus, M and NSP5 represent attractive vaccine candidate T cell antigens, which should be evaluated further in the context of PRRSV vaccine development.
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Affiliation(s)
- Helen Mokhtar
- Virology Department, Animal and Plant Health Agency, Addlestone, UK; Department of Microbial and Cellular Sciences, University of Surrey, Guildford, UK
| | - Miriam Pedrera
- Virology Department, Animal and Plant Health Agency , Addlestone , UK
| | | | - Lucia Biffar
- Virology Department, Animal and Plant Health Agency , Addlestone , UK
| | - Sabine E Hammer
- Department of Pathobiology, Institute of Immunology, University of Veterinary Medicine Vienna , Vienna , Austria
| | - Lise K Kvisgaard
- National Veterinary Institute, Technical University of Denmark , Frederiksberg , Denmark
| | - Lars E Larsen
- National Veterinary Institute, Technical University of Denmark , Frederiksberg , Denmark
| | - Graham R Stewart
- Department of Microbial and Cellular Sciences, University of Surrey , Guildford , UK
| | | | - Falko Steinbach
- Virology Department, Animal and Plant Health Agency , Addlestone , UK
| | - Simon P Graham
- Virology Department, Animal and Plant Health Agency , Addlestone , UK
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14
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Lee JA, Lee NH, Lee JB, Park SY, Song CS, Choi IS, Lee SW. Augmented immune responses in pigs immunized with an inactivated porcine reproductive and respiratory syndrome virus containing the deglycosylated glycoprotein 5 under field conditions. Clin Exp Vaccine Res 2016; 5:70-4. [PMID: 26866026 PMCID: PMC4742602 DOI: 10.7774/cevr.2016.5.1.70] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 11/02/2015] [Accepted: 12/03/2015] [Indexed: 01/19/2023] Open
Abstract
Purpose Porcine reproductive and respiratory syndrome virus (PRRSV) leads to major economic losses in the swine industry. Vaccination is the most effective method to control the disease by PRRSV. Materials and Methods In this study, the efficacy of a glycoprotein (GP) 5-modified inactivated vaccine was investigated in pigs. The study was performed in three farms: farm A, which was porcine reproductive and respiratory syndrome (PRRS)-negative, farm B (PRRS-active), which showed clinical signs of PRRS but had not used vaccines, and farm C (PRRS-stable), which had a history of endemic PRRS over the past years, but showed no more clinical signs after periodic administration of modified live virus vaccine. Results The inactivated vaccine induced great enhancement in serum neutralizing antibody titer, which was sufficient to protect pigs from further infections of PRRSV in a farm where pre-existing virus was circulating. Conclusion These results indicated that vaccination with the inactivated vaccine composed of viruses possessing deglycosylated GP5 would provide enhanced protection to pigs from farms suffering from endemic PRRSV.
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Affiliation(s)
- Jung-Ah Lee
- College of Veterinary Medicine, Konkuk University, Seoul, Korea.; Division of Vaccine Research, Korea National Institute of Health, Korea Centers for Disease Control and Prevention, Cheongju, Korea
| | - Nak-Hyung Lee
- College of Veterinary Medicine, Konkuk University, Seoul, Korea
| | - Joong-Bok Lee
- College of Veterinary Medicine, Konkuk University, Seoul, Korea
| | - Seung-Yong Park
- College of Veterinary Medicine, Konkuk University, Seoul, Korea
| | - Chang-Seon Song
- College of Veterinary Medicine, Konkuk University, Seoul, Korea
| | - In-Soo Choi
- College of Veterinary Medicine, Konkuk University, Seoul, Korea
| | - Sang-Won Lee
- College of Veterinary Medicine, Konkuk University, Seoul, Korea
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15
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Abstract
In approaching the development of a veterinary vaccine, researchers must choose from a bewildering array of options that can be combined to enhance benefit. The choice and combination of options is not just driven by efficacy, but also consideration of the cost, practicality, and challenges faced in licensing the product. In this review we set out the different choices faced by veterinary vaccine developers, highlight some issues, and propose some pressing needs to be addressed.
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Affiliation(s)
- Mark A Chambers
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, GU2 7AL, UK.
- Department of Bacteriology, Animal and Plant Health Agency, Addlestone, Surrey, KT15 3NB, UK.
| | - Simon P Graham
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, GU2 7AL, UK
- The Pirbright Institute, Ash Road, Pirbright, Woking, GU24 0NF, UK
| | - Roberto M La Ragione
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, GU2 7AL, UK
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16
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Production and evaluation of virus-like particles displaying immunogenic epitopes of porcine reproductive and respiratory syndrome virus (PRRSV). Int J Mol Sci 2015; 16:8382-96. [PMID: 25874763 PMCID: PMC4425087 DOI: 10.3390/ijms16048382] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 03/27/2015] [Accepted: 04/01/2015] [Indexed: 12/15/2022] Open
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is the most significant infectious disease currently affecting the swine industry worldwide. Several inactivated and modified live vaccines (MLV) have been developed to curb PRRSV infections. However, the efficacy and safety of these vaccines are unsatisfactory, and hence, there is a strong demand for the development of new PRRS universal vaccines. Virus-like particle (VLP)-based vaccines are gaining increasing acceptance compared to subunit vaccines, as they present the antigens in a more veritable conformation and are readily recognized by the immune system. Hepatitis B virus core antigen (HBcAg) has been successfully used as a carrier for more than 100 viral sequences. In this study, hybrid HBcAg VLPs were generated by fusion of the conserved protective epitopes of PRRSV and expressed in E. coli. An optimized purification protocol was developed to obtain hybrid HBcAg VLP protein from the inclusion bodies. This hybrid HBcAg VLP protein self-assembled to 23-nm VLPs that were shown to block virus infection of susceptible cells when tested on MARC 145 cells. Together with the safety of non-infectious and non-replicable VLPs and the low cost of production through E. coli fermentation, this hybrid VLP could be a promising vaccine candidate for PRRS.
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18
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Construction and immunogenicity of DNA vaccines encoding fusion protein of porcine IFN- λ 1 and GP5 gene of porcine reproductive and respiratory syndrome virus. BIOMED RESEARCH INTERNATIONAL 2013; 2013:318698. [PMID: 24490154 PMCID: PMC3884778 DOI: 10.1155/2013/318698] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 11/29/2013] [Indexed: 01/05/2023]
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) has been mainly responsible for the catastrophic economic losses in pig industry worldwide. The commercial vaccines only provide a limited protection against PRRSV infection. Thus, the focus and direction is to develop safer and more effective vaccines in the research field of PRRS. The immune modulators are being considered to enhance the effectiveness of PRRSV vaccines. IFN-λ1 belongs to type III interferon, a new interferon family. IFN-λ1 is an important cytokine with multiple functions in innate and acquired immunity. In this study, porcine IFN-λ1 (PoIFN-λ1) was evaluated for its adjuvant effects on the immunity of a DNA vaccine carrying the GP5 gene of PRRSV. Groups of mice were immunized twice at 2-week interval with 100 μg of the plasmid DNA vaccine pcDNA3.1-SynORF5, pcDNA3.1-PoIFN-λ1-SynORF5, and the blank vector pcDNA3.1, respectively. The results showed that pcDNA3.1-PoIFN-λ1-SynORF5 can significantly enhance GP5-specific ELISA antibody, PRRSV-specific neutralizing antibody, IFN-γ level, and lymphocyte proliferation rather than the responses induced by pcDNA3.1-SynORF5. Therefore, type III interferon PoIFN-λ1 could enhance the immune responses of DNA vaccine of PRRSV, highlighting the potential value of PoIFN-λ1 as a molecular adjuvant in the prevention of PRRSV infection.
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19
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Liu JK, Wei CH, Yang XY, Hou XL, Dai AL, Li XH, Wei MK, Pan XZ. Genetic diversity and evolutionary characterization of Chinese porcine reproductive and respiratory syndrome viruses based on NSP2 and ORF5. Arch Virol 2013; 158:1811-6. [PMID: 23525729 DOI: 10.1007/s00705-013-1669-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 02/08/2013] [Indexed: 11/30/2022]
Abstract
To more fully understand the extent of genetic diversity of PRRSV in China, we analyzed the Nsp2 and ORF5 gene sequences of 35 representative PRRSV isolates from 2008 to 2012. Sequence analysis revealed that the Nsp2 and ORF5 genes have undergone genetic variation. Furthermore, the isolate FJLYDX04 contains five insertions at positions 599 to 603 and is the first isolate from China reported to have an insertion in Nsp2. Our results suggest that the highly pathogenic PRRSV has become the dominant strain in China and that Chinese PRRSV has undergone rapid evolution and can circumvent immune responses induced by currently used vaccines.
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Affiliation(s)
- Jian-Kui Liu
- College of Life Sciences of Longyan University, Longyan 364012, Fujian, China
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20
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Roques E, Girard A, St-Louis MC, Massie B, Gagnon CA, Lessard M, Archambault D. Immunogenic and protective properties of GP5 and M structural proteins of porcine reproductive and respiratory syndrome virus expressed from replicating but nondisseminating adenovectors. Vet Res 2013; 44:17. [PMID: 23497101 PMCID: PMC3608016 DOI: 10.1186/1297-9716-44-17] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Accepted: 02/13/2013] [Indexed: 02/08/2023] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) is responsible for significant economic losses in the porcine industry. Currently available commercial vaccines do not allow optimal and safe protection. In this study, replicating but nondisseminating adenovectors (rAdV) were used for the first time in pigs for vaccinal purposes. They were expressing the PRRSV matrix M protein in fusion with either the envelope GP5 wild-type protein (M-GP5) which carries the major neutralizing antibody (NAb)-inducing epitope or a mutant form of GP5 (M-GP5m) developed to theoretically increase the NAb immune response. Three groups of fourteen piglets were immunized both intramuscularly and intranasally at 3-week intervals with rAdV expressing the green fluorescent protein (GFP, used as a negative control), M-GP5 or M-GP5m. Two additional groups of pigs were primed with M-GP5m-expressing rAdV followed by a boost with bacterially-expressed recombinant wild-type GP5 or were immunized twice with a PRRSV inactivated commercial vaccine. The results show that the rAdV expressing the fusion proteins of interest induced systemic and mucosal PRRSV GP5-specific antibody response as determined in an ELISA. Moreover the prime with M-GP5m-expressing rAdV and boost with recombinant GP5 showed the highest antibody response against GP5. Following PRRSV experimental challenge, pigs immunized twice with rAdV expressing either M-GP5 or M-GP5m developed partial protection as shown by a decrease in viremia overtime. The lowest viremia levels and/or percentages of macroscopic lung lesions were obtained in pigs immunized twice with either the rAdV expressing M-GP5m or the PRRSV inactivated commercial vaccine.
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Affiliation(s)
- Elodie Roques
- Department of Biological Sciences, University of Québec at Montréal, Succursale Centre-Ville, P,O, Box 8888, Montréal, Québec, H3C 3P8, Canada.
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21
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Díaz I, Ganges L, Galindo-Cardiel I, Tarradas J, Álvarez B, Lorca-Oró C, Pujols J, Gimeno M, Darwich L, Domingo M, Domínguez J, Mateu E. Immunization with DNA Vaccines Containing Porcine Reproductive and Respiratory Syndrome Virus Open Reading Frames 5, 6, and 7 May Be Related to the Exacerbation of Clinical Disease after an Experimental Challenge. Viral Immunol 2013; 26:93-101. [DOI: 10.1089/vim.2012.0041] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Ivan Díaz
- Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Llilianne Ganges
- Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
- Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
| | - Iván Galindo-Cardiel
- Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
- Departament de Sanitat i Anatomia Animals, Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Joan Tarradas
- Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Belén Álvarez
- Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
| | - Cristina Lorca-Oró
- Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Joan Pujols
- Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
- Institut de Recerca i Tecnologia Agroalimentàries (IRTA), Barcelona, Spain
| | - Mariona Gimeno
- Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
- Departament de Sanitat i Anatomia Animals, Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Laila Darwich
- Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
- Departament de Sanitat i Anatomia Animals, Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Mariano Domingo
- Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
- Departament de Sanitat i Anatomia Animals, Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Javier Domínguez
- Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Madrid, Spain
| | - Enric Mateu
- Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
- Departament de Sanitat i Anatomia Animals, Campus de la Universitat Autònoma de Barcelona, Barcelona, Spain
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Pujhari S, Baig TT, Hansra S, Zakhartchouk AN. Development of a DNA-launched replicon as a vaccine for porcine reproductive and respiratory syndrome virus. Virus Res 2013; 173:321-6. [PMID: 23353778 DOI: 10.1016/j.virusres.2013.01.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 12/20/2012] [Accepted: 01/14/2013] [Indexed: 02/04/2023]
Abstract
Though a modified live attenuated vaccine (MLV) is available against porcine reproductive and respiratory syndrome virus (PRRSV), its limitations in protective efficacy, safety and few others warrant the development of newer vaccines. In this study, we have constructed a propagation-defective DNA-launched PRRSV replicon as a vaccine candidate and evaluated its immunogenicity and protective efficacy in a group of pigs along with MLV vaccinated group. Our data showed that prior to the intranasal challenge with a homologous strain of PRRSV, only MLV vaccinated pigs developed antibody response measured by ELISA and none of the pigs in any group developed PRRSV neutralizing antibodies in serum. The MLV vaccinated group also showed high PRRSV-specific INF-γ response, whereas the replicon-vaccinated pigs showed low but detectable INF-γ response. After 14 days post challenge, all groups showed similar PRRSV-specific serum neutralizing titers and were positive for PRRSV-specific ELISA antibody. In addition, the replicon-vaccinated group showed a significant reduction in viremia in comparison to the control group. In conclusion, vaccination with the PRRSV DNA-launched replicon decreased the viremia and viral load in bronchoalveolar lavage fluids of the PRRSV-challenged pigs and increased numbers of IFN-γ producing cells. Thus, the vaccine is partially protective and is a potential vaccine candidate for future with further improvement. The possible means of improvement is the expression of immunostimulatory genes by the replicon. We demonstrated the feasibility of this approach by expression of a foreign gene encoding firefly luciferase after transfection of cultured cells with the replicon plasmid DNA.
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Affiliation(s)
- Sujit Pujhari
- Vaccine and Infectious Disease Organization - International Vaccine Center (VIDO-InterVac), University of Saskatchewan, 120 Veterinary Road, Saskatoon, SK S7N 5E3, Canada
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23
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Kim WI, Kim JJ, Cha SH, Wu WH, Cooper V, Evans R, Choi EJ, Yoon KJ. Significance of genetic variation of PRRSV ORF5 in virus neutralization and molecular determinants corresponding to cross neutralization among PRRS viruses. Vet Microbiol 2012; 162:10-22. [PMID: 22959007 DOI: 10.1016/j.vetmic.2012.08.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 07/26/2012] [Accepted: 08/12/2012] [Indexed: 01/21/2023]
Abstract
A high rate of genetic and antigenic variability among porcine reproductive and respiratory syndrome viruses (PRRSVs) hampers effective prevention and control of the disease caused by PRRSV. The major envelope protein (GP5) encoded by the ORF5 of PRRSV has a critical role in inducing virus neutralizing (VN) antibody and cross protection among different strains of PRRSV. This study was conducted to identify sequence elements related to cross neutralization by comparing the ORF5 sequences of 69 field isolates in conjunction with their susceptibility to VN antibody raised against the VR2332 strain in vitro and in vivo. Five common variable sites (amino acid position 32-34, 38-39, 57-59, 137 and 151) were identified between susceptible and resistant viral isolates. Mutants whose ORF5 amino acid sequences were substituted with the sequences corresponding to the 5 identified common variable sites individually or concurrently were generated from a VR2332-backboned infectious clone by site mutagenesis. The change in the susceptibility of the mutants to VN antibodies specific for VR2332 or a heterologous PRRSV was assessed to determine the association of those 5 identified sites with cross neutralization. Among the five sites, the changes of amino acid sequences at three sites (32-34, 38-39, and 57-59) located in the N-terminal ectodomain of ORF5 significantly influenced the susceptibility of the mutant viruses to VN antibody, suggesting that sequence homology at these sites can be utilized as genetic markers to predict the degree of cross neutralization among different PRRSVs.
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Affiliation(s)
- Won-Il Kim
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, USA
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24
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Zhou F, Liang S, Chen AH, Singh CO, Bhaskar R, Niu YS, Miao YG. A transgenic Marc-145 cell line of piggyBac transposon-derived targeting shRNA interference against porcine reproductive and respiratory syndrome virus. Vet Res Commun 2012; 36:99-105. [PMID: 22297554 DOI: 10.1007/s11259-012-9519-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/13/2012] [Indexed: 10/14/2022]
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is now considered to be one of the most important diseases in countries with intensive swine industries. The two major membrane-associated proteins of porcine reproductive and respiratory syndrome virus (PRRSV), GP5 and M (encoded by ORF5 and ORF6 genes, respectively), are associated as disulfide-linked heterodimers (GP5/M) in the virus particle. In this study, we designed 5 of the small hairpin RNAs (shRNAs) targeting the GP5 and M gene of PRRSV respectively, and investigated their inhibition to the production of PRRSV. The highest activity displayed in shRNAs of the ORF6e sequence (nts 261-279), which the inhibition rate reached was 99.09%. The result suggests that RNAi technology might serve as a potential molecular strategy for PRRSV therapy. Furthermore, the transgenic Marc-145 cell line of piggyBac transposon-derived targeting shRNA interference against PRRS virus was established. It presented stable inhibition to the replication and amplification of PRRS. The work implied that shRNAs targeting the GP5 and M gene of PRRSV may be used as potential RNA vaccines in vivo, and supplied the screening methods of transformed pig embryonic fibroblast which are prerequisite for the disease-resistant transgenic pigs to PRRS.
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Affiliation(s)
- Fang Zhou
- Key Laboratory of Animal Virology of Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou 310058, People’s Republic of China
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25
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Charerntantanakul W, Kasinrerk W. Plasmids expressing interleukin-10 short hairpin RNA mediate IL-10 knockdown and enhance tumor necrosis factor alpha and interferon gamma expressions in response to porcine reproductive and respiratory syndrome virus. Vet Immunol Immunopathol 2012; 146:159-68. [DOI: 10.1016/j.vetimm.2012.02.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2011] [Revised: 01/25/2012] [Accepted: 02/29/2012] [Indexed: 12/18/2022]
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26
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Vimolmangkang S, Gasic K, Soria-Guerra R, Rosales-Mendoza S, Moreno-Fierros L, Korban SS. Expression of the nucleocapsid protein of porcine reproductive and respiratory syndrome virus in soybean seed yields an immunogenic antigenic protein. PLANTA 2012; 235:513-22. [PMID: 21971995 DOI: 10.1007/s00425-011-1523-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Accepted: 09/20/2011] [Indexed: 05/31/2023]
Abstract
Porcine reproductive and respiratory syndrome (PRRS), caused by the PRRS virus (PRRSV), is a serious disease of swine and contributes to severe worldwide economic losses in swine production. Current vaccines against PRRS rely on the use of an attenuated-live virus; however, these are unreliable. Thus, alternative effective vaccines against PRRS are needed. Plant-based subunit vaccines offer viable, safe, and environmentally friendly alternatives to conventional vaccines. In this study, efforts have been undertaken to develop a soybean-based vaccine against PRRSV. A construct carrying a synthesized PRRSV-ORF7 antigen, nucleocapsid N protein of PRRSV, has been introduced into soybean, Glycine max (L.) Merrill. cvs. Jack and Kunitz, using Agrobacterium-mediated transformation. Transgenic plants carrying the sORF7 transgene have been successfully generated. Molecular analyses of T(0) plants confirmed integration of the transgene and transcription of the PRRSV-ORF7. Presence of a 15-kDa protein in seeds of T(1) transgenic lines was confirmed by Western blot analysis using PRRSV-ORF7 antisera. The amount of the antigenic protein accumulating in seeds of these transgenic lines was up to 0.65% of the total soluble protein (TSP). A significant induction of a specific immune response, both humoral and mucosal, against PRRSV-ORF7 was observed following intragastric immunization of BALB/c female mice with transgenic soybean seeds. These findings provide a 'proof of concept', and serve as a critical step in the development of a subunit plant-based vaccine against PRRS.
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Affiliation(s)
- Sornkanok Vimolmangkang
- Department of Natural Resources and Environmental Sciences, University of Illinois, Urbana, IL 61801, USA
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Charerntantanakul W. Porcine reproductive and respiratory syndrome virus vaccines: Immunogenicity, efficacy and safety aspects. World J Virol 2012; 1:23-30. [PMID: 24175208 PMCID: PMC3782261 DOI: 10.5501/wjv.v1.i1.23] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 09/21/2011] [Accepted: 09/29/2011] [Indexed: 02/05/2023] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) infection is the leading cause of economic casualty in swine industry worldwide. The virus can cause reproductive failure, respiratory disease, and growth retardation in the pigs. This review deals with current status of commercial PRRS vaccines presently used to control PRRS. The review focuses on the immunogenicity, protective efficacy and safety aspects of the vaccines. Commercial PRRS modified-live virus (MLV) vaccine elicits delayed humoral and cell-mediated immune responses following vaccination. The vaccine confers late but effective protection against genetically homologous PRRSV, and partial protection against genetically heterologous virus. The MLV vaccine is of concern for its safety as the vaccine virus can revert to virulence and cause diseases. PRRS killed virus (KV) vaccine, on the other hand, is safe but confers limited protection against either homologous or heterologous virus. The KV vaccine yet helps reduce disease severity when administered to the PRRSV-infected pigs. Although efforts have been made to improve the immunogenicity, efficacy and safety of PRRS vaccines, a better vaccine is still needed in order to protect against PRRSV.
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Affiliation(s)
- Wasin Charerntantanakul
- Wasin Charerntantanakul, Research Laboratory for Immunity Enhancement in Humans and Domestic Animals, Program of Biotechnology, Faculty of Science, Maejo University, Chiang Mai 50290, Thailand
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Li G, Shi N, Suo S, Cui J, Zarlenga D, Ren X. Vaccination of mice with ORF5 plasmid DNA of PRRSV; enhanced effects by co-immunizing with porcine IL-15. Immunol Invest 2011; 41:231-48. [PMID: 22017604 DOI: 10.3109/08820139.2011.614306] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The open reading frame (ORF) 5 of porcine reproductive and respiratory syndrome virus (PRRSV) encodes a major envelope glycoprotein designated GP5. The GP5 protein is a candidate for vaccinating against PRRSV infection. In this study, recombinant plasmids bearing the PRRSV GP5 gene (pVAX-GP5) or the porcine interleukin 15 gene (pVAX-IL15) were generated. Mice were vaccinated with these gene constructs singularly or in combination, and subsequent humoral and cellular immune responses were evaluated. Proliferation assays showed that the number of T lymphocytes in the peripheral blood and spleens of treated mice were elevated by pVAX-GP5 and significantly enhanced by combination therapy involving pVAX-IL15. Flow cytometry data showed that the numbers of CD4+ and CD8+ T cells were also higher in treated mice. Both pVAX-GP5 treatment alone and in combination with pVAX-IL15 resulted in elevated antibody levels as demonstrated by indirect ELISA. The pVAX-IL15 gene construct served as a molecular adjuvant in conjunction with the pVAX-GP5 to enhance the immune responses where intermediate doses of pVAX-IL15 were most effective.
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Affiliation(s)
- Guangxing Li
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
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Prieto C, Martínez-Lobo FJ, Díez-Fuertes F, Aguilar-Calvo P, Simarro I, Castro JM. Immunisation of pigs with a major envelope protein sub-unit vaccine against porcine reproductive and respiratory syndrome virus (PRRSV) results in enhanced clinical disease following experimental challenge. Vet J 2011; 189:323-9. [PMID: 20713312 PMCID: PMC7172774 DOI: 10.1016/j.tvjl.2010.07.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 07/06/2010] [Accepted: 07/12/2010] [Indexed: 12/23/2022]
Abstract
Disease exacerbation was observed in pigs challenged with virulent porcine reproductive and respiratory syndrome virus (PRRSV) following immunisation with a recombinant GP5 sub-unit PRRSV vaccine (rGP5) produced in E. coli. Eighteen animals were divided into three experimental groups: group A were immunised twice IM with rGP5, 21 days apart; group B acted as positive controls (challenged but not immunised); and group C were negative controls. Pigs in groups A and B were challenged 21 days after the second immunisation of the group A animals. Following challenge, three pigs given rGP5 exhibited more severe clinical signs than the positive controls, including respiratory distress and progressive weight-loss. Although not statistically significant, the more severe disease exhibited by group A animals may suggest previous immunisation as a contributory factor. The mechanisms of these findings remain unclear and no association could be established between the severity of disease, non-neutralising antibody concentrations and tissue viral loads.
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30
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Epidemiology and evolutionary characteristics of the porcine reproductive and respiratory syndrome virus in China between 2006 and 2010. J Clin Microbiol 2011; 49:3175-83. [PMID: 21775536 DOI: 10.1128/jcm.00234-11] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In 2006, an emerging highly pathogenic strain of porcine reproductive and respiratory syndrome virus (PRRSV), which causes continuous high fever and a high proportion of deaths in vaccinated pigs of all ages, broke out in mainland China and spread rapidly to neighboring countries. To examine the epidemiology and evolutionary characteristics of Chinese PRRSV after the 2006 outbreak, we tested 2,981 clinical samples collected from 2006 to 2010 in China, determined 153 Nsp2 sequences and 249 ORF5 sequences, and analyzed the epidemiology and genetic diversity of Chinese PRRSV. Our results showed that the percentage of PRRSV-positive specimens collected from sick pigs averaged 60.85% in the past 5 years and that the highly pathogenic PRRSV has become the dominant strain in China. Furthermore, a reemerging strain which apparently evolved from the highly pathogenic PRRSV strain in 2006 appeared to be widely prevalent in China from 2009 onwards. Sequence analyses revealed that the hypervariable region of Nsp2 in most of the isolates contained a discontinuous deletion equivalent to 30 amino acids, along with other types of deletions. Extensive amino acid substitutions in the GP5 sequence translated from ORF5 were found, particularly in the potential neutralization epitope and the N-glycosylation sites. Our results suggest that Chinese PRRSV has undergone rapid evolution and can circumvent immune responses induced by currently used vaccines. Information from this study will help in understanding the evolutionary characteristics of Chinese PRRSV and assist ongoing efforts to develop and use PRRSV vaccines in the future.
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Zhang W, Lin Y, Bai Y, Tong T, Wang Q, Liu N, Liu G, Xiao Y, Yang T, Bu Z, Tong G, Wu D. Identification of CD8+ cytotoxic T lymphocyte epitopes from porcine reproductive and respiratory syndrome virus matrix protein in BALB/c mice. Virol J 2011; 8:263. [PMID: 21619712 PMCID: PMC3126774 DOI: 10.1186/1743-422x-8-263] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2010] [Accepted: 05/30/2011] [Indexed: 02/02/2023] Open
Abstract
Twenty-seven nanopeptides derived from the matrix (M) protein of porcine reproductive and respiratory syndrome virus (PRRSV) were screened for their ability to elicit a recall interferon-γ (IFN-γ) response from the splenocytes of BALB/c mice following DNA vaccination and a booster vaccination with recombinant vaccinia virus rWR-PRRSV-M. We identified two peptides (amino acid residues K93FITSRCRL and F57GYMTFVHF) as CD8+ cytotoxic T lymphocyte (CTL) epitopes. These peptides elicited significant numbers of IFN-γ secreting cells, compared with other M nonapeptides and one irrelevant nonapeptide. Bioinformatics analysis showed that the former is an H-2Kd-restricted CTL epitope, and the latter is an H-2Dd-restricted CTL epitope. Multiple amino acid sequence alignment among different PRRSV M sequences submitted to GenBank indicated that these two CTL epitopes are strongly conserved, and they should therefore be considered for further research on the mechanisms of cellular immune responses to PRRSV.
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Affiliation(s)
- Weijun Zhang
- The Key Laboratory of Veterinary Public Health, Ministry of Agriculture, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, PR China
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32
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Han YW, Kim SB, Rahman M, Uyangaa E, Lee BM, Kim JH, Park KI, Hong JT, Han SB, Eo SK. Systemic and mucosal immunity induced by attenuated Salmonella enterica serovar Typhimurium expressing ORF7 of porcine reproductive and respiratory syndrome virus. Comp Immunol Microbiol Infect Dis 2011; 34:335-45. [PMID: 21543119 DOI: 10.1016/j.cimid.2011.04.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2010] [Revised: 03/22/2011] [Accepted: 04/04/2011] [Indexed: 01/25/2023]
Abstract
Oral administration of attenuated Salmonella vaccine may provide valuable advantages such as low cost, easy preparation, and safety. Attenuated Salmonella vaccines also serve as carriers of foreign antigens and immunomodulatory cytokines. Presently, an attenuated Salmonella enterica serovar Typhimurium strain was used as a carrier for open reading frame 7 (ORF7) protein of porcine reproductive and respiratory syndrome virus (PRRSV), a swine pathogen of significant global economic importance. Initially, an attenuated S. enterica serovar Typhimurium expressing ORF7 gene derived from PRRSV Korean isolate was constructed. Following oral administration of a single dose of the attenuated Salmonella vaccine expressing PRRSV ORF7, humoral and cell-mediated immune responses specific for ORF7 were induced at both systemic and mucosal sites including spleen, mesenteric lymph node, Peyer's patch, and laminar propria, as evaluated by determining serum ORF7-specific IgG and mucosal IgA responses, as well as Th1- and Th2-type cytokine production from antigen-stimulated T cells. The induced humoral responses were sustained for at least 12weeks post-immunization. In particular, the immunized mice displayed immune responses to both the foreign ORF7 antigen and Salmonella itself. The results indicate the value of attenuated S. enterica serovar Typhimurium as an oral carrier of PRRSV antigenic proteins to induce effective systemic and mucosal immunity.
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Affiliation(s)
- Young Woo Han
- College of Veterinary Medicine and Bio-Safety Research Institute, Chonbuk National University, Jeonju, Republic of Korea
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Cai J, Ma Y, Li J, Yan C, Hu R, Zhang J. Construction and characterization of a recombinant canine adenovirus expressing GP5 and M proteins of porcine reproductive and respiratory syndrome virus. J Vet Med Sci 2010; 72:1035-40. [PMID: 20467206 DOI: 10.1292/jvms.10-0061] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The causative agent of porcine reproductive and respiratory syndrome (PRRS) is PRRS virus (PRRSV), which belongs to the family Arteriviridae. GP5/M protein complex of PRRSV binds to sialoadhesion expressed on the cells to infect the cells. In this study, we developed a canine adenovirus type 2 (CAV-2) recombinant, termed rCAV2-GP5/M, expressing GP5 and M proteins. To evaluate the immunogenicity of the recombinant virus, mice were inoculated subcutaneously with rCAV2-GP5/M, and specific antibodies against PRRSV in the sera were measured by enzyme-linked immunosorbent assay and the viral neutralization test. Two weeks post-immunization (w.p.i.), anti-PRRSV antibodies were detected in the sera, slightly increased by booster immunization at four w.p.i., and then gradually decreased. The viral neutralizing test showed that neutralizing antibodies were present in the sera collected at two w.p.i., increased by booster immunization, and reached the maximum titer at six w.p.i. Lymphocyte proliferation responding to PRRSV antigens was also observed from two w.p.i. Although further studies are needed to evaluate the usefulness of the recombinant virus to protect pigs from PPRSV, we succeeded in developing a candidate vaccine against PPRSV infection by using CAV-2 vector.
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Affiliation(s)
- Jinshun Cai
- Laboratory Animal Center, Jilin University, Changchun, Jilin Province, China
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34
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Zhou JX, Xue JD, Yu T, Zhang JB, Liu Y, Jiang N, Li YL, Hu RL. Immune responses in pigs induced by recombinant canine adenovirus 2 expressing the glycoprotein 5 of porcine reproductive and respiratory syndrome virus. Vet Res Commun 2010; 34:371-80. [PMID: 20432066 DOI: 10.1007/s11259-010-9364-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/12/2010] [Indexed: 01/11/2023]
Abstract
To develop a new type vaccine for porcine reproductive and respiratory syndrome (PRRS) prevention by using canine adenovirus 2(CAV-2) as vector, the Glycoprotein 5(GP5) gene from PRRSV strain JL was amplified by RT-PCR, and the expression cassette of GP5 was constructed using the human cytomegalovirus (HCMV) promoter and the simian virus 40 (SV40) early mRNA polyadenylation signal. The expression cassette of Glycoprotein 5 was cloned into the CAV-2 genome in which E3 region had been partly deleted, and the recombinant virus (CAV-2-GP5) was obtained by transfecting the recombinant CAV-2-GP5 genome into MDCK cells together with Lipofectamine 2000. Immunization trial in pigs with the recombinant virus CAV-2-GP5 showed that CAV-2-GP5 could stimulate a specific immune response to PRRSV. Immune response to the GP5 and PRRSV was confirmed by ELISA, neutralization test and lymphocyte proliferative responses, and western blotting confirmed expression of GP5 by the vector in cells. These results indicated that CAV-2 may serve as a vector for development of PRRSV vaccine in pigs, and the CAV-2-GP5 might be a candidate vaccine to be tested for preventing PRRSV infection.
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Affiliation(s)
- J-X Zhou
- Laboratory of Epidemiology, Veterinary Research Institute, Academy of Military Medical Science, 1068 Qinglong Road, Changchun, Jilin, People's Republic of China
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35
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Kimman TG, Cornelissen LA, Moormann RJ, Rebel JMJ, Stockhofe-Zurwieden N. Challenges for porcine reproductive and respiratory syndrome virus (PRRSV) vaccinology. Vaccine 2009; 27:3704-18. [PMID: 19464553 DOI: 10.1016/j.vaccine.2009.04.022] [Citation(s) in RCA: 277] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Revised: 03/30/2009] [Accepted: 04/07/2009] [Indexed: 01/11/2023]
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) continues to be a threat for the pig industry. Vaccines have been developed, but these failed to provide sustainable disease control, in particular against genetically unrelated strains. Here we give an overview of current knowledge and gaps in our knowledge that may be relevant for the development of a future generation of more effective vaccines. PRRSV replicates in cells of the monocyte/macrophage lineage, induces apoptosis and necrosis, interferes with the induction of a proinflammatory response, only slowly induces a specific antiviral response, and may cause persistent infections. The virus appears to use several evasion strategies to circumvent both innate and acquired immunity, including interference with antigen presentation, antibody-mediated enhancement, reduced cell surface expression of viral proteins, and shielding of neutralizing epitopes. In particular the downregulation of type I interferon-alpha production appears to interfere with the induction of acquired immunity. Current vaccines are ineffective because they suffer both from the immune evasion strategies of the virus and the antigenic heterogeneity of field strains. Future vaccines therefore must "uncouple" the immune evasion and apoptogenic/necrotic properties of the virus from its immunogenic properties, and they should induce a broad immune response covering the plasticity of its major antigenic sites. Alternatively, the composition of the vaccine should be changed regularly to reflect presently and locally circulating strains. Preferably new vaccines should also allow discriminating infected from vaccinated pigs to support a virus elimination strategy. Challenges in vaccine development are the incompletely known mechanisms of immune evasion and immunity, lack of knowledge of viral sequences that are responsible for the pathogenic and immunosuppressive properties of the virus, lack of knowledge of the forces that drive antigenic heterogeneity and its consequences for immunogenicity, and a viral genome that is relatively intolerant for subtle changes at functional sites.
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Affiliation(s)
- Tjeerd G Kimman
- Central Veterinary Institute of Wageningen UR (CVI), P.O. Box 65, 8200 AB Lelystad, The Netherlands.
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36
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Li B, Xiao S, Wang Y, Xu S, Jiang Y, Chen H, Fang L. Immunogenicity of the highly pathogenic porcine reproductive and respiratory syndrome virus GP5 protein encoded by a synthetic ORF5 gene. Vaccine 2009; 27:1957-63. [PMID: 19368777 DOI: 10.1016/j.vaccine.2009.01.098] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Revised: 01/12/2009] [Accepted: 01/22/2009] [Indexed: 11/16/2022]
Abstract
Since May 2006, a highly pathogenic porcine reproductive and respiratory syndrome virus (PRRSV), which causes continuous high fever and a high proportion of deaths in vaccinated pigs of all ages, has emerged and prevailed in Mainland China. Huge efforts should be made towards the development of an efficient vaccine against the highly pathogenic PRRSV. Although the ORF5-encoded GP5 is the most important immunogenic protein, accumulating evidences have demonstrated that incomplete protection conferred by GP5-based vaccines. The inability to induce robust protective immunity has been postulated to be associated with the presence of a non-neutralizing decoy epitope and heavy glycosylation in close to its neutralizing epitope. In this study, a synthetic ORF5 gene (SynORF5) was engineered with the codon usage optimized for mammalian cell expression based on the native ORF5 gene of highly pathogenic PRRSV strain WUH3. Additional modifications, i.e., inserting a Pan DR T-helper cell epitope (PADRE) between the neutralizing epitope and the non-neutralizing decoy epitope, and mutating four potential N-glycosylation sites (N30, N34, N35 and N51) were also included in the synthetic ORF5 gene. The immunogenicity of the SynORF5-encoded GP5 was evaluated by DNA vaccination in mice and piglets. Results showed that significantly enhanced GP5-specific ELISA antibody, PRRSV-specific neutralizing antibody, IFN-gamma level, as well as lymphocyte proliferation response, could be induced in mice and piglets immunized with DNA construct encoding the modified GP5 than those received DNA vaccine expressing the native GP5. The enhanced immunogenicity of the modified GP5 will be useful to facilitate the development of efficient vaccines against the highly pathogenic PRRSV in the future.
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Affiliation(s)
- Bin Li
- Division of Animal Infectious Diseases, State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China
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37
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Hou YH, Chen J, Tong GZ, Tian ZJ, Zhou YJ, Li GX, Li X, Peng JM, An TQ, Yang HC. A recombinant plasmid co-expressing swine ubiquitin and the GP5 encoding-gene of porcine reproductive and respiratory syndrome virus induces protective immunity in piglets. Vaccine 2008; 26:1438-49. [DOI: 10.1016/j.vaccine.2007.12.057] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2007] [Revised: 12/06/2007] [Accepted: 12/28/2007] [Indexed: 10/22/2022]
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38
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Wang S, Fang L, Fan H, Jiang Y, Pan Y, Luo R, Zhao Q, Chen H, Xiao S. Construction and immunogenicity of pseudotype baculovirus expressing GP5 and M protein of porcine reproductive and respiratory syndrome virus. Vaccine 2007; 25:8220-7. [DOI: 10.1016/j.vaccine.2007.09.069] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Revised: 09/19/2007] [Accepted: 09/25/2007] [Indexed: 12/27/2022]
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Han J, Liu G, Wang Y, Faaberg KS. Identification of nonessential regions of the nsp2 replicase protein of porcine reproductive and respiratory syndrome virus strain VR-2332 for replication in cell culture. J Virol 2007; 81:9878-90. [PMID: 17522233 PMCID: PMC2045381 DOI: 10.1128/jvi.00562-07] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The nonstructural protein 2 (nsp2) of porcine reproductive and respiratory syndrome virus (PRRSV) is a multidomain protein and has been shown to undergo remarkable genetic variation, primarily in its middle region, while exhibiting high conservation in the N-terminal putative protease domain and the C-terminal predicted transmembrane region. A reverse genetics system of PRRSV North American prototype VR-2332 was developed to explore the importance of different regions of nsp2 for viral replication. A series of mutants with in-frame deletions in the nsp2 coding region were engineered, and infectious viruses were subsequently recovered from transfected cells and further characterized. The results demonstrated that the cysteine protease domain (PL2), the PL2 downstream flanking sequence (amino acids [aa] 181 to 323), and the putative transmembrane domain were critical for replication. In contrast, the segment of nsp2 preceding the PL2 domain (aa 13 to 35) was dispensable for viral replication, and the nsp2 middle hypervariable region (aa 324 to 813) tolerated 100-aa or 200-aa deletions but could not be removed as a whole; the largest deletion was about 400 aa (nsp2Delta324-726). Characterization of the mutants demonstrated that those with small deletions possessed growth kinetics and RNA expression profiles similar to those of the parental virus, while the nsp2Delta324-726 mutant displayed decreased cytolytic activity on MARC-145 cells and did not develop visible plaques. Finally, the utilization of the genetic flexibility of nsp2 to express foreign genes was examined by inserting the gene encoding green fluorescent protein (GFP) in frame into one nsp2 deletion mutant construct. The recombinant virus was viable but impaired and unstable and gradually gained parental growth kinetics by the loss of most of the GFP gene.
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Affiliation(s)
- Jun Han
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN 55108, USA
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40
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Fuller DH, Loudon P, Schmaljohn C. Preclinical and clinical progress of particle-mediated DNA vaccines for infectious diseases. Methods 2007; 40:86-97. [PMID: 16997717 DOI: 10.1016/j.ymeth.2006.05.022] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2006] [Accepted: 05/10/2006] [Indexed: 11/23/2022] Open
Abstract
This review provides an overview of studies employing particle-mediated epidermal delivery (PMED) or the gene gun to administer DNA vaccines for infectious diseases in preclinical studies employing large animal models and in human clinical trials. It reviews the immunogenicity and protective efficacy of PMED DNA vaccines in nonhuman primates and swine and studies that have directly compared the effectiveness of PMED in these large animal models to existing licensed vaccines and intramuscular or intradermal delivery of DNA vaccines with a needle. Various clinical trials employing PMED have been completed and an overview of the immunogenicity, safety, and tolerability of this approach in humans is described. Finally, efforts currently in progress for commercial development of particle-mediated DNA vaccines are discussed.
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Affiliation(s)
- Deborah H Fuller
- Department of Molecular Genetics and Biochemistry, University of Pittsburgh, School of Medicine, 260 Kappa Drive, PA 15238, USA.
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41
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Jiang Y, Fang L, Xiao S, Zhang H, Pan Y, Luo R, Li B, Chen H. Immunogenicity and protective efficacy of recombinant pseudorabies virus expressing the two major membrane-associated proteins of porcine reproductive and respiratory syndrome virus. Vaccine 2006; 25:547-60. [PMID: 16920232 DOI: 10.1016/j.vaccine.2006.07.032] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Revised: 07/18/2006] [Accepted: 07/21/2006] [Indexed: 02/06/2023]
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) infection still remains today as the most significant health threat to swine and poses a challenge to current vaccination strategies. To develop a new generation of vaccine against PRRSV, a live attenuated pseudorabies virus (PRV) was used as vaccine vector to express the two major membrane-associated proteins (GP5 or M) of PRRSV in various forms. Four PRV recombinants, rPRV-GP5 (expressing native GP5), rPRV-GP5m (expressing GP5m, a modified GP5), rPRV-GP5-M (co-expressing GP5 and M proteins), rPRV-GP5m-M (co-expressing GP5m and M proteins) were generated. Mouse immunized with all these recombinants developed comparable PRV-specific humoral immune responses and provided complete protection against a lethal PRV challenge. However, the highest level of PRRSV-specific neutralizing antibodies and lymphocyte proliferative responses was observed in mice immunized with rPRV-GP5m-M. The immunogenicity and protective efficiency of rPRV-GP5m-M were further evaluated in the piglets. Compared to commercial PRRSV killed vaccine, detectable PRRSV-specific neutralizing antibody and higher lymphocyte proliferative responses could be developed in piglets immunized with rPRV-GP5m-M before virus challenge. Furthermore, more efficient protection against a PRRSV challenge was obtained in piglets immunized with rPRV-GP5m-M, as showed by the balanced body-temperature fluctuation, shorter-term viremia, lower proportion of virus load in nasal and oropharyngeal scrapings and tissues, and milder lung lesions. These data indicate that the recombinant rPRV-GP5m-M is a promising candidate bivalent vaccine against both PRV and PRRSV infection.
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Affiliation(s)
- Yunbo Jiang
- Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, PR China
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42
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Barfoed AM, Rodriguez F, Therrien D, Borrego B, Sobrino F, Kamstrup S. DNA immunization with 2C FMDV non-structural protein reveals the presence of an immunodominant CD8+, CTL epitope for Balb/c mice. Antiviral Res 2006; 72:178-89. [PMID: 16890298 DOI: 10.1016/j.antiviral.2006.07.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2006] [Revised: 06/27/2006] [Accepted: 07/04/2006] [Indexed: 10/24/2022]
Abstract
Outbreaks of foot and mouth disease virus (FMDV) have devastating economic consequences in affected areas. The presence of multiple serotypes and virus variants makes vaccination complicated. A better understanding of protective immune mechanisms may help in development of novel vaccines with cross protective capacity. While much attention has been devoted to humoral responses to FMDV, less is known about the role of cell-mediated responses in protective immunity. Predictions of potential CTL epitopes by two different computer algorithms identified the viral 2C protein as containing a potential murine H2-Kd CTL epitope located in its amino-terminal half. DNA vaccination of mice with a plasmid expressing the 2C protein and a fragment thereof confirmed that this was indeed a CTL epitope, as shown by interferon gamma (IFN-gamma) induction in CD8+, CD44(hi) splenocytes after in vitro stimulation with peptides containing the amino acid sequence KYKDAKEWL, predicted for the CTL epitope. A peptide with the variant sequence KYKEAKEWL induced similar responses, indicating tolerability towards a conservative substitution at the altered residue. Virus infection likewise induced a measurable CTL response against KYKDAKEWL, although less clear due to a higher background of IFN-gamma production in splenocytes from infected mice. Challenge of vaccinated mice showed that the CTL response induced by the 2C protein was not protective, since viremia and mortality were unaffected by vaccination. The implications for vaccine development are discussed in the context of cross-serotype reactive responses.
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Affiliation(s)
- Annette Malene Barfoed
- Danish Institute for Food and Veterinary Research, Lindholm, DK-4771 Kalvehave, Denmark.
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Fang L, Jiang Y, Xiao S, Niu C, Zhang H, Chen H. Enhanced immunogenicity of the modified GP5 of porcine reproductive and respiratory syndrome virus. Virus Genes 2006; 32:5-11. [PMID: 16525729 DOI: 10.1007/s11262-005-5839-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2005] [Accepted: 05/15/2005] [Indexed: 10/24/2022]
Abstract
The ORF5-encoded major envelope glycoprotein (GP5) is one of the key immunogenic proteins of the porcine reproductive and respiratory syndrome virus (PRRSV) and is the leading target for the development of the new generation of vaccines against PRRS. However, weak and tardy neutralizing antibodies have been elicited in several developed experimental vaccines expressing PRRSV GP5. More recent evidence has demonstrated a non-neutralizing decoy epitope upstream of the neutralizing epitope of GP5, which might prevent the development of a strong neutralizing antibody response against PRRSV. In the present study, we modified the ORF5 gene by inserting a Pan DR T-helper cell epitope (PADRE) between the neutralizing epitope and the decoy epitope to minimize or eliminate the decoy effect of the non-neutralizing epitope. The immunogenicity of the modified GP5 was further evaluated using DNA vaccination. The results showed that significantly enhanced neutralizing antibodies were elicited in mice immunized with the DNA construct expressing the modified GP5 compared with the native GP5. Slightly increased levels of GP5-specific ELISA antibodies and T-cell proliferative activities were also observed. These results indicate that the high immunogenicity of the modified GP5 might facilitate the development of improved PRRS vaccines in the future.
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Affiliation(s)
- Liurong Fang
- Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, Hubei, P.R.China
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Rompato G, Ling E, Chen Z, Van Kruiningen H, Garmendia AE. Positive inductive effect of IL-2 on virus-specific cellular responses elicited by a PRRSV-ORF7 DNA vaccine in swine. Vet Immunol Immunopathol 2006; 109:151-60. [PMID: 16162362 DOI: 10.1016/j.vetimm.2005.08.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2005] [Revised: 08/03/2005] [Accepted: 08/08/2005] [Indexed: 12/24/2022]
Abstract
This study investigated the effect of swine interleukin 2 (IL-2) and swine interleukin 4 (IL-4) on the development of immune responses induced by a PRRSV-ORF7 DNA vaccine (phCMV-ORF7). The two cytokines were cloned separately in the eukaryotic expression vector phCMV, and delivered via gene gun as adjuvants for the DNA vaccine. Groups of 3-week-old certified PRRSV-free, castrated male, Yorkshire crossbred pigs, were vaccinated with or without the IL-2 or IL-4. The ensuing humoral and cellular immune responses were analyzed by a PRRSV-specific ELISA, and by an in vitro blastogenic response of peripheral blood mononuclear cells (PBMC) stimulated by viral antigen, respectively. The animals were boosted 21 days post-vaccination and challenged 28 days afterward. The virus loads post-challenge were measured by real time PCR. The group of swine receiving the vaccine plus IL-2 had significant virus-specific blastogenic responses 3 weeks after the vaccine-cytokine boost, when compared to those of the experimental pigs that received the vaccine plus IL-4, vaccine alone, unvaccinated controls or the pigs vaccinated with the DNA vaccine cloned in the reverse orientation (phCMV-ORF7(Rev)). None of the experimental swine had detectable specific antibodies against the virus during the vaccination phase. The virus load peak in vaccinated animals was delayed by about 72h as compared to that of the control pigs (unvaccinated and vaccinated with the phCMV-ORF7(Rev) construct). Interestingly, animals that received the phCMV-ORF7 vaccine alone consistently had low virus loads throughout the study. These results demonstrate that IL-2 has a positive inductive effect on the activation of vaccine-induced virus-specific cellular immunity, while IL-4 appeared to have a suppressive effect. Our data also suggest that ORF7 may play a role in reducing the virus load in PRRSV infected animals.
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Affiliation(s)
- G Rompato
- Department of Pathobioloy and Veterinary Sciences, University of Connecticut, 61 N. Eagleville Rd, Storrs, CT, USA
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