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Wu YC, Lai HX, Li JM, Fung KM, Tseng TS. Discovery of a potent inhibitor, D-132, targeting AsfvPolX, via protein-DNA complex-guided pharmacophore screening and in vitro molecular characterizations. Virus Res 2024; 344:199359. [PMID: 38521505 PMCID: PMC10995865 DOI: 10.1016/j.virusres.2024.199359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 03/15/2024] [Accepted: 03/17/2024] [Indexed: 03/25/2024]
Abstract
The heightened transmissibility and capacity of African swine fever virus (ASFV) induce fatal diseases in domestic pigs and wild boars, posing significant economic repercussions and global threats. Despite extensive research efforts, the development of potent vaccines or treatments for ASFV remains a persistent challenge. Recently, inhibiting the AsfvPolX, a key DNA repair enzyme, emerges as a feasible strategy to disrupt viral replication and control ASFV infections. In this study, a comprehensive approach involving pharmacophore-based inhibitor screening, coupled with biochemical and biophysical analyses, were implemented to identify, characterize, and validate potential inhibitors targeting AsfvPolX. The constructed pharmacophore model, Phar-PolX-S, demonstrated efficacy in identifying a potent inhibitor, D-132 (IC50 = 2.8 ± 0.2 µM), disrupting the formation of the AsfvPolX-DNA complex. Notably, D-132 exhibited strong binding to AsfvPolX (KD = 6.9 ± 2.2 µM) through a slow-on-fast-off binding mechanism. Employing molecular modeling, it was elucidated that D-132 predominantly binds in-between the palm and finger domains of AsfvPolX, with crucial residues (R42, N48, Q98, E100, F102, and F116) identified as hotspots for structure-based inhibitor optimization. Distinctively characterized by a 1,2,5,6-tetrathiocane with modifications at the 3 and 8 positions involving ethanesulfonates, D-132 holds considerable promise as a lead compound for the development of innovative agents to combat ASFV infections.
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Affiliation(s)
- Yi-Chen Wu
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 40202, Taiwan
| | - Hui-Xiang Lai
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 40202, Taiwan
| | - Ji-Min Li
- Institute of Precision Medicine, College of Medicine, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan; Center of Excellence for Metabolic Associated Fatty Liver Disease, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan
| | - Kit-Man Fung
- Biomedical Translation Research Center (BioTReC), Academia Sinica, Taipei, 11529, Taiwan
| | - Tien-Sheng Tseng
- Institute of Molecular Biology, National Chung Hsing University, Taichung, 40202, Taiwan.
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2
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Gao S, Zuo W, Kang C, Zou Z, Zhang K, Qiu J, Shang X, Li J, Zhang Y, Zuo Q, Zhao Y, Jin M. Saccharomyces cerevisiae oral immunization in mice using multi-antigen of the African swine fever virus elicits a robust immune response. Front Immunol 2024; 15:1373656. [PMID: 38742108 PMCID: PMC11089227 DOI: 10.3389/fimmu.2024.1373656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Accepted: 04/05/2024] [Indexed: 05/16/2024] Open
Abstract
African swine fever virus (ASFV) is one of the most complex viruses. ASFV is a serious threat to the global swine industry because no commercial vaccines against this virus are currently available except in Vietnam. Moreover, ASFV is highly stable in the environment and can survive in water, feed, and aerosols for a long time. ASFV is transmitted through the digestive and respiratory tract. Mucosal immunity is the first line of defense against ASFV. Saccharomyces cerevisiae (SC), which has been certified by the U.S. Food and Drug Administration and has a generally recognized as safe status in the food industry, was used for oral immunization in this study. ASFV antigens were effectively expressed in recombinant SC strains with high DNA copy numbers and stable growth though surface display technology and chromosome engineering (δ-integration). The recombinant SC strains containing eight ASFV antigens-KP177R, E183L, E199L, CP204L, E248R, EP402R, B602L, and B646L- induced strong humoral and mucosal immune responses in mice. There was no antigenic competition, and these antigens induced Th1 and Th2 cellular immune responses. Therefore, the oral immunization strategy using recombinant SC strains containing multiple ASFV antigens demonstrate potential for future testing in swine, including challenge studies to evaluate its efficacy as a vaccine against ASFV.
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Affiliation(s)
- Shuo Gao
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Wenfeng Zuo
- Research Institute of Wuhan Keqian Biology Co., Ltd, Wuhan, China
| | - Chao Kang
- Research Institute of Wuhan Keqian Biology Co., Ltd, Wuhan, China
| | - Zhong Zou
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Kaiqi Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China
| | - Jun Qiu
- College of Animal Sciences, Yangtze University, Jingzhou, Hubei, China
| | - Xiaomin Shang
- Research Institute of Wuhan Keqian Biology Co., Ltd, Wuhan, China
| | - Jingjing Li
- Research Institute of Wuhan Keqian Biology Co., Ltd, Wuhan, China
| | - Yuanfeng Zhang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
- Research Institute of Wuhan Keqian Biology Co., Ltd, Wuhan, China
| | - Qi Zuo
- Research Institute of Wuhan Keqian Biology Co., Ltd, Wuhan, China
| | - Ya Zhao
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Meilin Jin
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
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Sun L, Zhang J, Shi L, Peng Y, Feng X, Huang F, Yang F, Li J, Wang S, Niu J, Liu J, Li Y, Li S, Chen Z. Development and Immunological Evaluation of a Multiantigen Thermostable Nanovaccine Adjuvanted with T-Cell-Activating Scaffold for African Swine Fever. ACS APPLIED BIO MATERIALS 2024; 7:1547-1557. [PMID: 38346262 DOI: 10.1021/acsabm.3c01035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
African swine fever is an acute and highly contagious infectious disease with a mortality rate of up to 100%. The lack of commercial vaccines and drugs is a serious economic threat to the global pig industry. Cell-mediated immunity plays an essential role in protection against viral infection. We previously reported the rational design of a T-cell-activating thermostable scaffold (RPT) for antigen delivery and improved cellular immunity. We conjugated antigens P30, P54, P72, CD2 V, and CP312R to RPT, using a SpyCatcher/SpyTag covalent attachment strategy to construct nanovaccines (multiantigens-RPT). Multiantigens-RPT exhibited significantly higher thermal, storage, and freeze-thaw stability. The specific antibodies IgG and IgG2a of the multiantigen-RPT-immunized were higher than the antigens cocktail-immunized by approximately 10-100 times. ELISpot demonstrated that more IFN-γ-secreting cells were produced by the multiantigen-RPT-immunized than by the antigens cocktail-immunized. Delivery of the multiantigen nanovaccine by a T-cell-activating scaffold induced strong humoral and cellular immune responses in mice and pigs and is a potentially useful candidate vaccine for the African swine fever virus.
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Affiliation(s)
- Lidan Sun
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang, Liaoning 110866, China
- Department of Cell Engineering, Beijing Institute of Biotechnology, Beijing 100850, China
- Beijing Tonghe Litai Biotechnology Co., Ltd. Beijing 100080, China
| | - Jinsong Zhang
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Lijun Shi
- Beijing Tonghe Litai Biotechnology Co., Ltd. Beijing 100080, China
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yuanli Peng
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Xiangning Feng
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Fang Huang
- Department of Cell Engineering, Beijing Institute of Biotechnology, Beijing 100850, China
| | - Feixia Yang
- Beijing Tonghe Litai Biotechnology Co., Ltd. Beijing 100080, China
| | - Jinyu Li
- Beijing Tonghe Litai Biotechnology Co., Ltd. Beijing 100080, China
| | - Shuo Wang
- Beijing Tonghe Litai Biotechnology Co., Ltd. Beijing 100080, China
| | - Jingqi Niu
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang, Liaoning 110866, China
| | - Jinling Liu
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang, Liaoning 110866, China
| | - Yingjun Li
- Beijing Tonghe Litai Biotechnology Co., Ltd. Beijing 100080, China
| | - Shanhu Li
- Department of Cell Engineering, Beijing Institute of Biotechnology, Beijing 100850, China
| | - Zeliang Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang, Liaoning 110866, China
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
- Key Laboratory of Zoonose Prevention and Control at Universities of Inner Mongolia Autonomous Region, Medical College, Inner Mongolia Minzu University, Tongliao 028000, China
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4
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Vu HLX, McVey DS. Recent progress on gene-deleted live-attenuated African swine fever virus vaccines. NPJ Vaccines 2024; 9:60. [PMID: 38480758 PMCID: PMC10937926 DOI: 10.1038/s41541-024-00845-9] [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: 08/02/2023] [Accepted: 02/21/2024] [Indexed: 03/17/2024] Open
Abstract
African Swine Fever (ASF) is a highly lethal viral disease in swine, with mortality rates approaching 100%. The disease has spread to many swine-producing countries, leading to significant economic losses and adversely impacting global food security. Extensive efforts have been directed toward developing effective ASF vaccines. Among the vaccinology approaches tested to date, live-attenuated virus (LAV) vaccines produced by rational deleting virulence genes from virulent African Swine Fever Virus (ASFV) strains have demonstrated promising safety and efficacy in experimental and field conditions. Many gene-deleted LAV vaccine candidates have been generated in recent years. The virulence genes targeted for deletion from the genome of virulent ASFV strains can be categorized into four groups: Genes implicated in viral genome replication and transcription, genes from the multigene family located at both 5' and 3' termini, genes participating in mediating hemadsorption and putative cellular attachment factors, and novel genes with no known functions. Some promising LAV vaccine candidates are generated by deleting a single viral virulence gene, whereas others are generated by simultaneously deleting multiple genes. This article summarizes the recent progress in developing and characterizing gene-deleted LAV vaccine candidates.
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Affiliation(s)
- Hiep L X Vu
- Department of Animal Science, and Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - D Scott McVey
- School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE, USA.
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Chandana MS, Nair SS, Chaturvedi VK, Abhishek, Pal S, Charan MSS, Balaji S, Saini S, Vasavi K, Deepa P. Recent progress and major gaps in the vaccine development for African swine fever. Braz J Microbiol 2024; 55:997-1010. [PMID: 38311710 PMCID: PMC10920543 DOI: 10.1007/s42770-024-01264-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 11/16/2023] [Indexed: 02/06/2024] Open
Abstract
The swine industry across the globe is recently facing a devastating situation imparted by a highly contagious and deadly viral disease, African swine fever. The disease is caused by a DNA virus, the African swine fever virus (ASFV) of the genus Asfivirus. ASFV affects both wild boars and domestic pigs resulting in an acute form of hemorrhagic fever. Since the first report in 1921, the disease remains endemic in some of the African countries. However, the recent occurrence of ASF outbreaks in Asia led to a fresh and formidable challenge to the global swine production industry. Culling of the infected animals along with the implementation of strict sanitary measures remains the only options to control this devastating disease. Efforts to develop an effective and safe vaccine against ASF began as early as in the mid-1960s. Different approaches have been employed for the development of effective ASF vaccines including inactivated vaccines, subunit vaccines, DNA vaccines, virus-vectored vaccines, and live attenuated vaccines (LAVs). Inactivated vaccines are a non-feasible strategy against ASF due to their inability to generate a complete cellular immune response. However genetically engineered vaccines, such as subunit vaccines, DNA vaccines, and virus vector vaccines, represent tailored approaches with minimal adverse effects and enhanced safety profiles. As per the available data, gene deleted LAVs appear to be the most potential vaccine candidates. Currently, a gene deleted LAV (ASFV-G-∆I177L), developed in Vietnam, stands as the sole commercially available vaccine against ASF. The major barrier to the goal of developing an effective vaccine is the critical gaps in the knowledge of ASFV biology and the immune response induced by ASFV infection. The precise contribution of various hosts, vectors, and environmental factors in the virus transmission must also be investigated in depth to unravel the disease epidemiology. In this review, we mainly focus on the recent progress in vaccine development against ASF and the major gaps associated with it.
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Affiliation(s)
- M S Chandana
- Division of Biological Standardization, ICAR-Indian Veterinary Research Institute, Uttar Pradesh, Izatnagar, Bareilly, 243 122, India.
| | - Sonu S Nair
- Division of Bacteriology and Mycology, ICAR-Indian Veterinary Research Institute, Uttar Pradesh, Izatnagar, Bareilly, 243 122, India.
| | - V K Chaturvedi
- Division of Bacteriology and Mycology, ICAR-Indian Veterinary Research Institute, Uttar Pradesh, Izatnagar, Bareilly, 243 122, India
| | - Abhishek
- Division of Bacteriology and Mycology, ICAR-Indian Veterinary Research Institute, Uttar Pradesh, Izatnagar, Bareilly, 243 122, India
| | - Santanu Pal
- Division of Bacteriology and Mycology, ICAR-Indian Veterinary Research Institute, Uttar Pradesh, Izatnagar, Bareilly, 243 122, India
| | | | - Shilpa Balaji
- Division of Virology, ICAR-Indian Veterinary Research Institute, Muktheswhar 263138, Utharakand, India
| | - Shubham Saini
- Division of Veterinary Public Health and Epidemiology, ICAR-Indian Veterinary Research Institute, Uttar Pradesh, Izatnagar, Bareilly, 243 122, India
| | - Koppu Vasavi
- Division of Biological Standardization, ICAR-Indian Veterinary Research Institute, Uttar Pradesh, Izatnagar, Bareilly, 243 122, India
| | - Poloju Deepa
- Division of CADRAD, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India
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6
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Borca MV, Ramirez-Medina E, Espinoza N, Rai A, Spinard E, Velazquez-Salinas L, Valladares A, Silva E, Burton L, Meyers A, Clark J, Wu P, Gay CG, Gladue DP. Deletion of the EP402R Gene from the Genome of African Swine Fever Vaccine Strain ASFV-G-∆I177L Provides the Potential Capability of Differentiating between Infected and Vaccinated Animals. Viruses 2024; 16:376. [PMID: 38543742 PMCID: PMC10974803 DOI: 10.3390/v16030376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Revised: 02/19/2024] [Accepted: 02/20/2024] [Indexed: 05/23/2024] Open
Abstract
The African swine fever virus (ASFV) mutant ASFV-G-∆I177L is a safe and efficacious vaccine which induces protection against the challenge of its parental virus, the Georgia 2010 isolate. Although a genetic DIVA (differentiation between infected and vaccinated animals) assay has been developed for this vaccine, still there is not a serological DIVA test for differentiating between animals vaccinated with ASFV-G-∆I177L and those infected with wild-type viruses. In this report, we describe the development of the ASFV-G-∆I177L mutant having deleted the EP402R gene, which encodes for the viral protein responsible for mediating the hemadsorption of swine erythrocytes. The resulting virus, ASFV-G-∆I177L/∆EP402R, does not have a decreased ability to replicates in swine macrophages when compared with the parental ASFV-G-∆I177L. Domestic pigs intramuscularly (IM) inoculated with either 102 or 106 HAD50 of ASFV-G-∆I177L/∆EP402R remained clinically normal, when compared with a group of mock-vaccinated animals, indicating the absence of residual virulence. Interestingly, an infectious virus could not be detected in the blood samples of the ASFV-G-∆I177L/∆EP402R-inoculated animals in either group at any of the time points tested. Furthermore, while all of the mock-inoculated animals presented a quick and lethal clinical form of ASF after the intramuscular inoculation challenge with 102 HAD50 of highly virulent parental field isolate Georgia 2010 (ASFV-G), all of the ASFV-G-∆I177L/∆EP402R-inoculated animals were protected, remaining clinically normal until the end of the observational period. Most of the ASFV-G-∆I177L/∆EP402R-inoculated pigs developed strong virus-specific antibody responses against viral antigens, reaching maximum levels at 28 days post inoculation. Importantly, all of the sera collected at that time point in the ASFV-G-∆I177L/∆EP402R-inoculated pigs did not react in a direct ELISA coated with the recombinant EP402R protein. Conversely, the EP402R protein was readily recognized by the pool of sera from the animals immunized with recombinant live attenuated vaccine candidates ASFV-G-∆I177L, ASFV-G-∆MGF, or ASFV-G-∆9GL/∆UK. Therefore, ASFV-G-∆I177L/∆EP402R is a novel, safe and efficacious candidate with potential to be used as an antigenically DIVA vaccine.
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Affiliation(s)
- Manuel V. Borca
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, U.S. Department of Agriculture, Agricultural Research Service, Orient, NY 11957, USA; (E.R.-M.); (N.E.); (A.R.); (E.S.); (L.V.-S.); (A.V.); (A.M.)
- Foreign Animal Disease Research Unit, U.S. Department of Agriculture, Agricultural Research Service, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Elizabeth Ramirez-Medina
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, U.S. Department of Agriculture, Agricultural Research Service, Orient, NY 11957, USA; (E.R.-M.); (N.E.); (A.R.); (E.S.); (L.V.-S.); (A.V.); (A.M.)
- Foreign Animal Disease Research Unit, U.S. Department of Agriculture, Agricultural Research Service, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Nallely Espinoza
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, U.S. Department of Agriculture, Agricultural Research Service, Orient, NY 11957, USA; (E.R.-M.); (N.E.); (A.R.); (E.S.); (L.V.-S.); (A.V.); (A.M.)
- Foreign Animal Disease Research Unit, U.S. Department of Agriculture, Agricultural Research Service, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Ayushi Rai
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, U.S. Department of Agriculture, Agricultural Research Service, Orient, NY 11957, USA; (E.R.-M.); (N.E.); (A.R.); (E.S.); (L.V.-S.); (A.V.); (A.M.)
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Edward Spinard
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, U.S. Department of Agriculture, Agricultural Research Service, Orient, NY 11957, USA; (E.R.-M.); (N.E.); (A.R.); (E.S.); (L.V.-S.); (A.V.); (A.M.)
- Foreign Animal Disease Research Unit, U.S. Department of Agriculture, Agricultural Research Service, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Lauro Velazquez-Salinas
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, U.S. Department of Agriculture, Agricultural Research Service, Orient, NY 11957, USA; (E.R.-M.); (N.E.); (A.R.); (E.S.); (L.V.-S.); (A.V.); (A.M.)
- Foreign Animal Disease Research Unit, U.S. Department of Agriculture, Agricultural Research Service, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Alyssa Valladares
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, U.S. Department of Agriculture, Agricultural Research Service, Orient, NY 11957, USA; (E.R.-M.); (N.E.); (A.R.); (E.S.); (L.V.-S.); (A.V.); (A.M.)
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Ediane Silva
- Foreign Animal Disease Research Unit, U.S. Department of Agriculture, Agricultural Research Service, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Leeanna Burton
- Foreign Animal Disease Research Unit, U.S. Department of Agriculture, Agricultural Research Service, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Amanda Meyers
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, U.S. Department of Agriculture, Agricultural Research Service, Orient, NY 11957, USA; (E.R.-M.); (N.E.); (A.R.); (E.S.); (L.V.-S.); (A.V.); (A.M.)
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Jason Clark
- Foreign Animal Disease Research Unit, U.S. Department of Agriculture, Agricultural Research Service, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
| | - Ping Wu
- Plum Island Animal Disease Center, U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Orient, NY 11957, USA;
| | - Cyril G. Gay
- Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705, USA;
| | - Douglas P. Gladue
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, U.S. Department of Agriculture, Agricultural Research Service, Orient, NY 11957, USA; (E.R.-M.); (N.E.); (A.R.); (E.S.); (L.V.-S.); (A.V.); (A.M.)
- Foreign Animal Disease Research Unit, U.S. Department of Agriculture, Agricultural Research Service, National Bio and Agro-Defense Facility, Manhattan, KS 66502, USA; (E.S.); (L.B.); (J.C.)
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7
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Li Y, Wang Z, Qing J, Hu D, Vo HT, Thi KT, Wang X, Li X. Application of propidium monoazide quantitative PCR to discriminate of infectious African swine fever viruses. Front Microbiol 2024; 14:1290302. [PMID: 38268706 PMCID: PMC10805820 DOI: 10.3389/fmicb.2023.1290302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 12/18/2023] [Indexed: 01/26/2024] Open
Abstract
Introduction The detection of African swine fever virus (ASFV) is commonly performed using quantitative real-time PCR (qPCR), a widely used virological method known for its high sensitivity and specificity. However, qPCR has a limitation in distinguishing between infectious and inactivated virus, which can lead to an overestimation of viral targets. Methods To provide insights into ASFV infectivity, we evaluated the suitability of PMAxx, an improved version of propidium monoazide (PMA), as a means to differentiate between infectious and non-infectious ASFV. Pre-treatment with 50 μM PMAxx for 15 min significantly reduced the qPCR signal of ASFV in the live vaccine. Additionally, thermal treatment at 85°C for 5 min effectively inactivated the live ASFV in the vaccine. Based on a standard curve, the sensitivity of the PMAxx-qPCR assay was estimated to be approximately 10 copies/μL. Furthermore, we observed a strong agreement between the results obtained from PMAxx-qPCR and pig challenge experiments. Moreover, we utilized the PMAxx-qPCR assay to investigate the persistence of ASFV, revealing a close relationship between viral persistence and factors such as temperature and type of piggery materials. Conclusion The findings of this study suggest that pre-treating viruses with PMAxx prior to qPCR is a reliable method for distinguishing between infectious and non-infectious ASFV. Thus, integrating of PMAxx-qPCR into routine diagnostic protocols holds potential for improving the interpretation of positive ASFV results obtained through qPCR.
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Affiliation(s)
- Yang Li
- Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd., (Shandong Engineering Laboratory of Pig and Poultry Healthy Breeding and Disease Diagnosis Technology), Dezhou, China
| | - Zewei Wang
- Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd., (Shandong Engineering Laboratory of Pig and Poultry Healthy Breeding and Disease Diagnosis Technology), Dezhou, China
| | - Jie Qing
- Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd., (Shandong Engineering Laboratory of Pig and Poultry Healthy Breeding and Disease Diagnosis Technology), Dezhou, China
| | - Dajun Hu
- New Hope Binh Phuoc livestock Co., Ltd., Huyen Hon Quan, Vietnam
| | - Hong Trang Vo
- New Hope Binh Phuoc livestock Co., Ltd., Huyen Hon Quan, Vietnam
| | - Kim Thanh Thi
- New Hope Binh Phuoc livestock Co., Ltd., Huyen Hon Quan, Vietnam
| | - Xinglong Wang
- College of Veterinary Medicine, Northwest A&F University, Xianyang, Yangling, China
| | - Xiaowen Li
- Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd., (Shandong Engineering Laboratory of Pig and Poultry Healthy Breeding and Disease Diagnosis Technology), Dezhou, China
- New Hope Binh Phuoc livestock Co., Ltd., Huyen Hon Quan, Vietnam
- College of Veterinary Medicine, Northwest A&F University, Xianyang, Yangling, China
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8
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Desmet C, Coelho-Cruz B, Mehn D, Colpo P, Ruiz-Moreno A. ASFV epitope mapping by high density peptides microarrays. Virus Res 2024; 339:199287. [PMID: 38029799 PMCID: PMC10711508 DOI: 10.1016/j.virusres.2023.199287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 11/22/2023] [Accepted: 11/26/2023] [Indexed: 12/01/2023]
Abstract
African swine fever (ASF) is an acute, highly contagious and deadly infectious disease. It is a threat to animal health with major potential economic and societal impact. Despite decades of ASF vaccine research, still some gaps in knowledge are hindering the development of a functional vaccine. Worth mentioning are gaps in understanding the mechanism of ASF infection and immunity, as well as the fact that - in case of this disease - virus proteins, so-called protective antigens, responsible for inducing protective immune responses in pigs are not identified yet. In this paper we elaborate on a methodology to identify protective antigens based on epitope mapping by microarray technology. High density peptide microarrays, combined with fluorescence scanning, have been used to analyze the interaction of peptide sequences of African swine fever virus (ASFV) proteins with antibodies present in inactivated serum from infected and healthy animals. The study evidenced ASFV proteins already under the radar for vaccine development, such as p54, and identified specific sequences in those proteins that may become the focus for future vaccine candidates. Such methodology is amenable to automation and high-throughput and may help developing better targeting for next generation vaccines.
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Affiliation(s)
- Cloé Desmet
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | | | - Dora Mehn
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Pascal Colpo
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Ana Ruiz-Moreno
- European Commission, Joint Research Centre (JRC), Ispra, Italy.
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9
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Juszkiewicz M, Walczak M, Woźniakowski G, Podgórska K. African Swine Fever: Transmission, Spread, and Control through Biosecurity and Disinfection, Including Polish Trends. Viruses 2023; 15:2275. [PMID: 38005951 PMCID: PMC10674562 DOI: 10.3390/v15112275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/11/2023] [Accepted: 11/17/2023] [Indexed: 11/26/2023] Open
Abstract
African swine fever is a contagious disease, affecting pigs and wild boars, which poses a major threat to the pig industry worldwide and, therefore, to the agricultural economies of many countries. Despite intensive studies, an effective vaccine against the disease has not yet been developed. Since 2007, ASFV has been circulating in Eastern and Central Europe, covering an increasingly large area. As of 2018, the disease is additionally spreading at an unprecedented scale in Southeast Asia, nearly ruining China's pig-producing sector and generating economic losses of approximately USD 111.2 billion in 2019. ASFV's high resistance to environmental conditions, together with the lack of an approved vaccine, plays a key role in the spread of the disease. Therefore, the biosecurity and disinfection of pig farms are the only effective tools through which to prevent ASFV from entering the farms. The selection of a disinfectant, with research-proven efficacy and proper use, taking into account environmental conditions, exposure time, pH range, and temperature, plays a crucial role in the disinfection process. Despite the significant importance of ASF epizootics, little information is available on the effectiveness of different disinfectants against ASFV. In this review, we have compiled the current knowledge on the transmission, spread, and control of ASF using the principles of biosecurity, with particular attention to disinfection, including a perspective based on Polish experience with ASF control.
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Affiliation(s)
- Małgorzata Juszkiewicz
- Department of Swine Diseases, National Veterinary Research Institute, Partyzantów 57 Avenue, 24-100 Puławy, Poland; (M.W.); (K.P.)
| | - Marek Walczak
- Department of Swine Diseases, National Veterinary Research Institute, Partyzantów 57 Avenue, 24-100 Puławy, Poland; (M.W.); (K.P.)
| | - Grzegorz Woźniakowski
- Department of Diagnostics and Clinical Sciences, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Toruń, Lwowska 1 Street, 87-100 Toruń, Poland;
| | - Katarzyna Podgórska
- Department of Swine Diseases, National Veterinary Research Institute, Partyzantów 57 Avenue, 24-100 Puławy, Poland; (M.W.); (K.P.)
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10
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Sun L, Niu J, Zhang J, Peng Y, Feng X, Huang F, Liu J, Li S, Chen Z. Thermostable T Cell Multiepitope Nanoparticle Antigens Inducing Potent Immune Responses against the Swine Fever Virus. ACS Infect Dis 2023; 9:2358-2368. [PMID: 37861250 DOI: 10.1021/acsinfecdis.3c00506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
African swine fever (ASF) is caused by the African swine fever virus (ASFV) and is a highly contagious, acute, febrile disease that has high morbidity and mortality rates in domestic and wild swine. However, a safe and effective vaccine against ASF remains unavailable as single antigens fail to provide sufficient protection. Therefore, a combination of multiple antigens with an efficient delivery system might be an alternative strategy. Herein, a de novo-designed antigen with multiple T-cell epitopes (TEPs) of ASFV was conjugated for surface display on self-assembled nanoparticles (NPs) of Aquifex aeolicus lumazine synthase (AaLS) and Quasibacillus thermotolerans encapsulin (QT) through the SpyCatcher/SpyTag system to construct nanovaccines (TEP-Spy-NPs). TEP-Spy-NPs exhibited significantly more thermal, storage, and freeze-thaw stability in comparison to TEP monomers. TEP-Spy-NPs were highly immunogenic and induced strong polyclonal antibody responses in mice and pigs. The specific antibody titers against the TEP of the TEP-Spy-AaLS and TEP-Spy-QT groups were significantly higher than those of the TEP monomer immune group after the second booster immunization. The antibody titer against TEP of the TEP-Spy-QT group was approximately twice that of the TEP-Spy-AaLS group in mice. ELISpot analysis demonstrated that more IFN-γ- and IL-2-secreting splenic lymphocytes were produced by TEP-Spy-AaLS- and TEP-Spy-QT-immunized mice than by TEP monomer-immunized mice. TEP-Spy-NPs elicited stronger cellular immunity and in vivo immunity in immunized pigs than did TEP monomers. Thus, the TEP nanovaccine successfully induced strong humoral and cellular immune responses in mice and pigs, and TEP-Spy-NPs have the potential as candidate vaccines for ASFV.
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Affiliation(s)
- Lidan Sun
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang, Liaoning 110866, China
- Department of Cell Engineering, Beijing Institute of Biotechnology, Beijing 100850, China
| | - Jingqi Niu
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang, Liaoning 110866, China
| | - Jinsong Zhang
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Yuanli Peng
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Xiangning Feng
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Fang Huang
- Department of Cell Engineering, Beijing Institute of Biotechnology, Beijing 100850, China
| | - Jinling Liu
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang, Liaoning 110866, China
| | - Shanhu Li
- Department of Cell Engineering, Beijing Institute of Biotechnology, Beijing 100850, China
| | - Zeliang Chen
- Key Laboratory of Livestock Infectious Diseases in Northeast China, Ministry of Education, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, No. 120 Dongling Road, Shenhe District, Shenyang, Liaoning 110866, China
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
- Key Laboratory of Zoonose Prevention and Control at Universities of Inner Mongolia Autonomous Region, Medical College, Inner Mongolia Minzu University, Tongliao 028000, China
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11
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Lim JW, Vu TTH, Le VP, Yeom M, Song D, Jeong DG, Park SK. Advanced Strategies for Developing Vaccines and Diagnostic Tools for African Swine Fever. Viruses 2023; 15:2169. [PMID: 38005846 PMCID: PMC10674204 DOI: 10.3390/v15112169] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 11/26/2023] Open
Abstract
African swine fever (ASF) is one of the most lethal infectious diseases affecting domestic pigs and wild boars of all ages. Over a span of 100 years, ASF has continued to spread over continents and adversely affects the global pig industry. To date, no vaccine or treatment has been approved. The complex genome structure and diverse variants facilitate the immune evasion of the ASF virus (ASFV). Recently, advanced technologies have been used to design various potential vaccine candidates and effective diagnostic tools. This review updates vaccine platforms that are currently being used worldwide, with a focus on genetically modified live attenuated vaccines, including an understanding of their potential efficacy and limitations of safety and stability. Furthermore, advanced ASFV detection technologies are presented that discuss and incorporate the challenges that remain to be addressed for conventional detection methods. We also highlight a nano-bio-based system that enhances sensitivity and specificity. A combination of prophylactic vaccines and point-of-care diagnostics can help effectively control the spread of ASFV.
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Affiliation(s)
- Jong-Woo Lim
- Department of Veterinary Medicine Virology Laboratory, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea; (J.-W.L.); (M.Y.); (D.S.)
| | - Thi Thu Hang Vu
- College of Pharmacy, Korea University, Sejong 30019, Republic of Korea;
| | - Van Phan Le
- Department of Veterinary Microbiology and Infectious Diseases, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi 131000, Vietnam;
| | - Minjoo Yeom
- Department of Veterinary Medicine Virology Laboratory, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea; (J.-W.L.); (M.Y.); (D.S.)
| | - Daesub Song
- Department of Veterinary Medicine Virology Laboratory, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea; (J.-W.L.); (M.Y.); (D.S.)
| | - Dae Gwin Jeong
- Bionanotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141, Republic of Korea
- Bio-Analytical Science Division, University of Science and Technology, Daejeon 34113, Republic of Korea
| | - Song-Kyu Park
- College of Pharmacy, Korea University, Sejong 30019, Republic of Korea;
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12
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Tng PYL, Al-Adwani L, Pauletto E, Hui JYK, Netherton CL. Capsid-Specific Antibody Responses of Domestic Pigs Immunized with Low-Virulent African Swine Fever Virus. Vaccines (Basel) 2023; 11:1577. [PMID: 37896980 PMCID: PMC10611099 DOI: 10.3390/vaccines11101577] [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: 09/08/2023] [Revised: 10/03/2023] [Accepted: 10/09/2023] [Indexed: 10/29/2023] Open
Abstract
African swine fever (ASF) is a lethal disease in pigs that has grave socio-economic implications worldwide. For the development of vaccines against the African swine fever virus (ASFV), immunogenic antigens that generate protective immune responses need to be identified. There are over 150 viral proteins-many of which are uncharacterized-and humoral immunity to ASFV has not been closely examined. To profile antigen-specific antibody responses, we developed luciferase-linked antibody capture assays (LACAs) for a panel of ASFV capsid proteins and screened sera from inbred and outbred animals that were previously immunized with low-virulent ASFV before challenge with virulent ASFV. Antibodies to B646L/p72, D117L/p17, M1249L, and E120R/p14.5 were detected in this study; however, we were unable to detect B438L-specific antibodies. Anti-B646L/p72 and B602L antibodies were associated with recovery from disease after challenges with genotype I OUR T88/1 but not genotype II Georgia 2007/1. Antibody responses against M1249L and E120R/p14.5 were observed in animals with reduced clinical signs and viremia. Here, we present LACAs as a tool for the targeted profiling of antigen-specific antibody responses to inform vaccine development.
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Affiliation(s)
- Priscilla Y. L. Tng
- The Pirbright Institute, Ash Road, Pirbright, Woking GU24 0NF, UK; (L.A.-A.); (E.P.); (J.Y.K.H.)
| | - Laila Al-Adwani
- The Pirbright Institute, Ash Road, Pirbright, Woking GU24 0NF, UK; (L.A.-A.); (E.P.); (J.Y.K.H.)
| | - Egle Pauletto
- The Pirbright Institute, Ash Road, Pirbright, Woking GU24 0NF, UK; (L.A.-A.); (E.P.); (J.Y.K.H.)
- The Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - Joshua Y. K. Hui
- The Pirbright Institute, Ash Road, Pirbright, Woking GU24 0NF, UK; (L.A.-A.); (E.P.); (J.Y.K.H.)
| | - Christopher L. Netherton
- The Pirbright Institute, Ash Road, Pirbright, Woking GU24 0NF, UK; (L.A.-A.); (E.P.); (J.Y.K.H.)
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13
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Pakotiprapha D, Kuhaudomlarp S, Tinikul R, Chanarat S. Bridging the Gap: Can COVID-19 Research Help Combat African Swine Fever? Viruses 2023; 15:1925. [PMID: 37766331 PMCID: PMC10536364 DOI: 10.3390/v15091925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/12/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023] Open
Abstract
African swine fever (ASF) is a highly contagious and economically devastating disease affecting domestic pigs and wild boar, caused by African swine fever virus (ASFV). Despite being harmless to humans, ASF poses significant challenges to the swine industry, due to sudden losses and trade restrictions. The ongoing COVID-19 pandemic has spurred an unparalleled global research effort, yielding remarkable advancements across scientific disciplines. In this review, we explore the potential technological spillover from COVID-19 research into ASF. Specifically, we assess the applicability of the diagnostic tools, vaccine development strategies, and biosecurity measures developed for COVID-19 for combating ASF. Additionally, we discuss the lessons learned from the pandemic in terms of surveillance systems and their implications for managing ASF. By bridging the gap between COVID-19 and ASF research, we highlight the potential for interdisciplinary collaboration and technological spillovers in the battle against ASF.
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Affiliation(s)
| | | | | | - Sittinan Chanarat
- Department of Biochemistry and Center for Excellence in Protein and Enzyme Technology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
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Bru G, Martínez-Candela M, Romero P, Navarro A, Martínez-Murcia A. Internal Validation of the ASFV MONODOSE dtec-qPCR Kit for African Swine Fever Virus Detection under the UNE-EN ISO/IEC 17025:2005 Criteria. Vet Sci 2023; 10:564. [PMID: 37756086 PMCID: PMC10535882 DOI: 10.3390/vetsci10090564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 08/17/2023] [Accepted: 09/06/2023] [Indexed: 09/28/2023] Open
Abstract
African swine fever virus is considered an emerging virus that causes African swine fever, a disease characterised by high mortality and elevated transmission rates and that, as it is for most other viral diseases, cannot be treated with specific drugs. Effective and reliable detection of the virus is relevant to prevent uncontrolled contagion among boar populations and to reduce economic losses. Moreover, animal health laboratories are demanding standardisation, optimisation and quality assurance of the available diagnostic assays. In the present study, the ASFV MONODOSE dtec-qPCR kit was validated following the UNE-EN ISO/IEC 17025:2005 guidelines. Analytical validation terms include in silico and in vitro specificity, sensitivity, efficiency and reliability (repeatability/reproducibility). Diagnostic validation of the method was assessed through the analysis of a total of 181 porcine samples originating from six different matrix types doped with African swine fever virus DNA received from the European reference laboratory for African Swine Fever (INIA-CISA, Madrid, Spain): whole blood, blood serum, kidney, heart, liver and tonsil. Results agreed with those obtained from a reference detection method also based on real-time PCR, endorsed by WOAH, but the ASFV MONODOSE dtec-qPCR kit incorporates some technical innovations and improvements which may benefit end-users. This kit, available worldwide with full analytical and diagnostic validation, can recognise all known ASFV genotypes and brings additional benefits to the current qPCR technology.
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Affiliation(s)
- Gema Bru
- Genetic PCR Solutions™, 03300 Orihuela, Spain
| | | | | | | | - Antonio Martínez-Murcia
- Genetic PCR Solutions™, 03300 Orihuela, Spain
- Department of Microbiology, University Miguel Hernández, 03312 Orihuela, Spain
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15
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Li D, Peng J, Wu J, Yi J, Wu P, Qi X, Ren J, Peng G, Duan X, Ru Y, Liu H, Tian H, Zheng H. African swine fever virus MGF-360-10L is a novel and crucial virulence factor that mediates ubiquitination and degradation of JAK1 by recruiting the E3 ubiquitin ligase HERC5. mBio 2023; 14:e0060623. [PMID: 37417777 PMCID: PMC10470787 DOI: 10.1128/mbio.00606-23] [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: 03/09/2023] [Accepted: 05/16/2023] [Indexed: 07/08/2023] Open
Abstract
African swine fever virus (ASFV) causes acute hemorrhagic infectious disease in pigs. The ASFV genome encodes various proteins that enable the virus to escape innate immunity; however, the underlying mechanisms are poorly understood. The present study found that ASFV MGF-360-10L significantly inhibits interferon (IFN)-β-triggered STAT1/2 promoter activation and the production of downstream IFN-stimulated genes (ISGs). ASFV MGF-360-10L deletion (ASFV-Δ10L) replication was impaired compared with the parental ASFV CN/GS/2018 strain, and more ISGs were induced by the ASFV-Δ10L in porcine alveolar macrophages in vitro. We found that MGF-360-10L mainly targets JAK1 and mediates its degradation in a dose-dependent manner. Meanwhile, MGF-360-10L also mediates the K48-linked ubiquitination of JAK1 at lysine residues 245 and 269 by recruiting the E3 ubiquitin ligase HERC5 (HECT and RLD domain-containing E3 ubiquitin protein ligase 5). The virulence of ASFV-Δ10L was significantly lower than that of the parental strain in vivo, which indicates that MGF-360-10L is a novel virulence factor of ASFV. Our findings elaborate the novel mechanism of MGF-360-10L on the STAT1/2 signaling pathway, expanding our understanding of the inhibition of host innate immunity by ASFV-encoded proteins and providing novel insights that could contribute to the development of African swine fever vaccines. IMPORTANCE African swine fever outbreaks remain a concern in some areas. There is no effective drug or commercial vaccine to prevent African swine fever virus (ASFV) infection. In the present study, we found that overexpression of MGF-360-10L strongly inhibited the interferon (IFN)-β-induced STAT1/2 signaling pathway and the production of IFN-stimulated genes (ISGs). Furthermore, we demonstrated that MGF-360-10L mediates the degradation and K48-linked ubiquitination of JAK1 by recruiting the E3 ubiquitin ligase HERC5. The virulence of ASFV with MGF-360-10L deletion was significantly less than parental ASFV CN/GS/2018. Our study identified a new virulence factor and revealed a novel mechanism by which MGF-360-10L inhibits the immune response, thus providing new insights into the vaccination strategies against ASFV.
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Affiliation(s)
- Dan Li
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Jiangling Peng
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Junhuang Wu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Jiamin Yi
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Panxue Wu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xiaolan Qi
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Jingjing Ren
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Gaochuang Peng
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xianghan Duan
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Yi Ru
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Huanan Liu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Hong Tian
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Haixue Zheng
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
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Shi K, Zhao K, Wei H, Zhou Q, Shi Y, Mo S, Long F, Hu L, Feng S, Mo M. Triplex Crystal Digital PCR for the Detection and Differentiation of the Wild-Type Strain and the MGF505-2R and I177L Gene-Deleted Strain of African Swine Fever Virus. Pathogens 2023; 12:1092. [PMID: 37764900 PMCID: PMC10534775 DOI: 10.3390/pathogens12091092] [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: 06/29/2023] [Revised: 08/24/2023] [Accepted: 08/25/2023] [Indexed: 09/29/2023] Open
Abstract
African swine fever (ASF) is a severe and highly contagious viral disease that affects domestic pigs and wild boars, characterized by a high fever and internal bleeding. The disease is caused by African swine fever virus (ASFV), which is prevalent worldwide and has led to significant economic losses in the global pig industry. In this study, three pairs of specific primers and TaqMan probes were designed for the ASFV B646L, MGF505-2R and I177L genes. After optimizing the reaction conditions of the annealing temperature, primer concentration and probe concentration, triplex crystal digital PCR (cdPCR) and triplex real-time quantitative PCR (qPCR) were developed for the detection and differentiation of the wild-type ASFV strain and the MGF505-2R and/or I177L gene-deleted ASFV strains. The results indicate that both triplex cdPCR and triplex qPCR were highly specific, sensitive and repeatable. The assays could detect only the B646L, MGF505-2R and I177L genes, without cross-reaction with other swine viruses (i.e., PRRSV, CSFV, PCV2, PCV3, PEDV, PDCoV and PRV). The limit of detection (LOD) of triplex cdPCR was 12 copies/reaction, and the LOD of triplex qPCR was 500 copies/reaction. The intra-assay and inter-assay coefficients of variation (CVs) for repeatability and reproducibility were less than 2.7% for triplex cdPCR and less than 1.8% for triplex qPCR. A total of 1510 clinical tissue samples were tested with both methods, and the positivity rates of ASFV were 14.17% (214/1510) with triplex cdPCR and 12.98% (196/1510) with triplex qPCR, with a coincidence rate of 98.81% between the two methods. The positivity rate for the MGF505-2R gene-deleted ASFV strains was 0.33% (5/1510), and no I177L gene-deleted ASFV strain was found. The results indicate that triplex cdPCR and triplex qPCR developed in this study can provide rapid, sensitive and accurate methods for the detection and differentiation of the ASFV B646L, MGF505-2R and I177L genes.
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Affiliation(s)
- Kaichuang Shi
- College of Animal Science and Technology, Guangxi University, Nanning 530005, China; (K.Z.); (Y.S.)
- Guangxi Center for Animal Disease Control and Prevention, Nanning 530001, China; (H.W.); (Q.Z.); (S.M.); (F.L.); (L.H.); (S.F.)
| | - Kang Zhao
- College of Animal Science and Technology, Guangxi University, Nanning 530005, China; (K.Z.); (Y.S.)
| | - Haina Wei
- Guangxi Center for Animal Disease Control and Prevention, Nanning 530001, China; (H.W.); (Q.Z.); (S.M.); (F.L.); (L.H.); (S.F.)
| | - Qingan Zhou
- Guangxi Center for Animal Disease Control and Prevention, Nanning 530001, China; (H.W.); (Q.Z.); (S.M.); (F.L.); (L.H.); (S.F.)
| | - Yuwen Shi
- College of Animal Science and Technology, Guangxi University, Nanning 530005, China; (K.Z.); (Y.S.)
| | - Shenglan Mo
- Guangxi Center for Animal Disease Control and Prevention, Nanning 530001, China; (H.W.); (Q.Z.); (S.M.); (F.L.); (L.H.); (S.F.)
| | - Feng Long
- Guangxi Center for Animal Disease Control and Prevention, Nanning 530001, China; (H.W.); (Q.Z.); (S.M.); (F.L.); (L.H.); (S.F.)
| | - Liping Hu
- Guangxi Center for Animal Disease Control and Prevention, Nanning 530001, China; (H.W.); (Q.Z.); (S.M.); (F.L.); (L.H.); (S.F.)
| | - Shuping Feng
- Guangxi Center for Animal Disease Control and Prevention, Nanning 530001, China; (H.W.); (Q.Z.); (S.M.); (F.L.); (L.H.); (S.F.)
| | - Meilan Mo
- College of Animal Science and Technology, Guangxi University, Nanning 530005, China; (K.Z.); (Y.S.)
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17
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Spinard E, Rai A, Osei-Bonsu J, O’Donnell V, Ababio PT, Tawiah-Yingar D, Arthur D, Baah D, Ramirez-Medina E, Espinoza N, Valladares A, Faburay B, Ambagala A, Odoom T, Borca MV, Gladue DP. The 2022 Outbreaks of African Swine Fever Virus Demonstrate the First Report of Genotype II in Ghana. Viruses 2023; 15:1722. [PMID: 37632064 PMCID: PMC10459280 DOI: 10.3390/v15081722] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/02/2023] [Accepted: 08/05/2023] [Indexed: 08/27/2023] Open
Abstract
African swine fever (ASF) is a lethal disease of domestic pigs that has been causing outbreaks for over a century in Africa ever since its first discovery in 1921. Since 1957, there have been sporadic outbreaks outside of Africa; however, no outbreak has been as devastating and as far-reaching as the current pandemic that originated from a 2007 outbreak in the Republic of Georgia. Derivatives with a high degree of similarity to the progenitor strain, ASFV-Georgia/2007, have been sequenced from various countries in Europe and Asia. However, the current strains circulating in Africa are largely unknown, and 24 different genotypes have been implicated in different outbreaks. In this study, ASF isolates were collected from samples from swine suspected of dying from ASF on farms in Ghana in early 2022. While previous studies determined that the circulating strains in Ghana were p72 Genotype I, we demonstrate here that the strains circulating in 2022 were derivatives of the p72 Genotype II pandemic strain. Therefore, this study demonstrates for the first time the emergence of Genotype II ASFV in Ghana.
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Affiliation(s)
- Edward Spinard
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.S.); (E.R.-M.); (N.E.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Unit Name, Manhattan, KS 66502, USA
- Center of Excellence for African Swine Fever Genomics, Guilford, CT 06437, USA (A.A.); (T.O.)
| | - Ayushi Rai
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.S.); (E.R.-M.); (N.E.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Unit Name, Manhattan, KS 66502, USA
| | - Jehadi Osei-Bonsu
- Accra Veterinary Laboratory of Veterinary Services Directorate, Accra P.O. Box GA184, Ghana (P.T.A.); (D.T.-Y.); (D.A.); (D.B.)
- Animal and Plant Inspection Service, USDA, Greenport, NY 11944, USA
| | - Vivian O’Donnell
- Departmenr of Libral Arts & Sciences, University of Illinois at Urbana-Champaign, Champaign, IL 61820, USA;
| | - Patrick T. Ababio
- Accra Veterinary Laboratory of Veterinary Services Directorate, Accra P.O. Box GA184, Ghana (P.T.A.); (D.T.-Y.); (D.A.); (D.B.)
| | - Daniel Tawiah-Yingar
- Accra Veterinary Laboratory of Veterinary Services Directorate, Accra P.O. Box GA184, Ghana (P.T.A.); (D.T.-Y.); (D.A.); (D.B.)
| | - Daniel Arthur
- Accra Veterinary Laboratory of Veterinary Services Directorate, Accra P.O. Box GA184, Ghana (P.T.A.); (D.T.-Y.); (D.A.); (D.B.)
| | - Daniel Baah
- Accra Veterinary Laboratory of Veterinary Services Directorate, Accra P.O. Box GA184, Ghana (P.T.A.); (D.T.-Y.); (D.A.); (D.B.)
| | - Elizabeth Ramirez-Medina
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.S.); (E.R.-M.); (N.E.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Unit Name, Manhattan, KS 66502, USA
| | - Nallely Espinoza
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.S.); (E.R.-M.); (N.E.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Unit Name, Manhattan, KS 66502, USA
| | - Alyssa Valladares
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.S.); (E.R.-M.); (N.E.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Unit Name, Manhattan, KS 66502, USA
| | - Bonto Faburay
- Center of Excellence for African Swine Fever Genomics, Guilford, CT 06437, USA (A.A.); (T.O.)
- Animal and Plant Inspection Service, USDA, Greenport, NY 11944, USA
| | - Aruna Ambagala
- Center of Excellence for African Swine Fever Genomics, Guilford, CT 06437, USA (A.A.); (T.O.)
- Animal and Plant Inspection Service, USDA, Greenport, NY 11944, USA
| | - Theophlius Odoom
- Center of Excellence for African Swine Fever Genomics, Guilford, CT 06437, USA (A.A.); (T.O.)
- Departmenr of Libral Arts & Sciences, University of Illinois at Urbana-Champaign, Champaign, IL 61820, USA;
| | - Manuel V. Borca
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.S.); (E.R.-M.); (N.E.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Unit Name, Manhattan, KS 66502, USA
- Center of Excellence for African Swine Fever Genomics, Guilford, CT 06437, USA (A.A.); (T.O.)
| | - Douglas P. Gladue
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Orient, NY 11957, USA; (E.S.); (E.R.-M.); (N.E.)
- U.S. Department of Agriculture, Agricultural Research Service, Foreign Animal Disease Research Unit, National Bio and Agro-Defense Facility, Unit Name, Manhattan, KS 66502, USA
- Center of Excellence for African Swine Fever Genomics, Guilford, CT 06437, USA (A.A.); (T.O.)
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18
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Gladue DP, Gomez-Lucas L, Largo E, Velazquez-Salinas L, Ramirez-Medina E, Torralba J, Queralt M, Alcaraz A, Nieva JL, Borca MV. African Swine Fever Virus Gene B117L Encodes a Small Protein Endowed with Low-pH-Dependent Membrane Permeabilizing Activity. J Virol 2023; 97:e0035023. [PMID: 37212688 PMCID: PMC10308923 DOI: 10.1128/jvi.00350-23] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 04/16/2023] [Indexed: 05/23/2023] Open
Abstract
African swine fever virus (ASFV) is causing a devastating pandemic in domestic and wild swine in Central Europe to East Asia, resulting in economic losses for the swine industry. The virus contains a large double-stranded DNA genome that contains more than 150 genes, most with no experimentally characterized function. In this study, we evaluate the potential function of the product of ASFV gene B117L, a 115-amino-acid integral membrane protein transcribed at late times during the virus replication cycle and showing no homology to any previously published protein. Hydrophobicity distribution along B117L confirmed the presence of a single transmembrane helix, which, in combination with flanking amphipathic sequences, composes a potential membrane-associated C-terminal domain of ca. 50 amino acids. Ectopic transient cell expression of the B117L gene as a green fluorescent protein (GFP) fusion protein revealed the colocalization with markers of the endoplasmic reticulum (ER). Intracellular localization of various B117L constructs also displayed a pattern for the formation of organized smooth ER (OSER) structures compatible with the presence of a single transmembrane helix with a cytoplasmic carboxy terminus. Using partially overlapping peptides, we further demonstrated that the B117L transmembrane helix has the capacity to establish spores and ion channels in membranes at low pH. Furthermore, our evolutionary analysis showed the high conservation of the transmembrane domain during the evolution of the B117L gene, indicating that the integrity of this domain is preserved by the action of the purifying selection. Collectively our data support a viroporin-like assistant role for the B117L gene-encoded product in ASFV entry. IMPORTANCE ASFV is responsible for an extensively distributed pandemic causing important economic losses in the pork industry in Eurasia. The development of countermeasures is partially limited by the insufficient knowledge regarding the function of the majority of the more than 150 genes present on the virus genome. Here, we provide data regarding the functional experimental evaluation of a previously uncharacterized ASFV gene, B117L. Our data suggest that the B117L gene encodes a small membrane protein that assists in the permeabilization of the ER-derived envelope during ASFV infection.
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Affiliation(s)
- Douglas P. Gladue
- Plum Island Animal Disease Center, ARS, USDA, Greenport, New York, USA
| | - Lidia Gomez-Lucas
- Instituto Biofisika (CSIC-UPV/EHU) and Department of Biochemistry and Molecular Biology, University of the Basque Country, Bilbao, Spain
| | - Eneko Largo
- Instituto Biofisika (CSIC-UPV/EHU) and Department of Biochemistry and Molecular Biology, University of the Basque Country, Bilbao, Spain
- Department of Immunology, Microbiology and Parasitology, Faculty of Pharmacy, University of the Basque Country UPV/EHU, Vitoria-Gasteiz, Spain
| | | | | | - Johana Torralba
- Instituto Biofisika (CSIC-UPV/EHU) and Department of Biochemistry and Molecular Biology, University of the Basque Country, Bilbao, Spain
| | - Maria Queralt
- Laboratory of Molecular Biophysics. Department of Physics. University Jaume I, Castellón, Spain
| | - Antonio Alcaraz
- Laboratory of Molecular Biophysics. Department of Physics. University Jaume I, Castellón, Spain
| | - Jose L. Nieva
- Instituto Biofisika (CSIC-UPV/EHU) and Department of Biochemistry and Molecular Biology, University of the Basque Country, Bilbao, Spain
| | - Manuel V. Borca
- Plum Island Animal Disease Center, ARS, USDA, Greenport, New York, USA
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19
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Ramirez-Medina E, Rai A, Espinoza N, Valladares A, Silva E, Velazquez-Salinas L, Borca MV, Gladue DP. Deletion of the H240R Gene in African Swine Fever Virus Partially Reduces Virus Virulence in Swine. Viruses 2023; 15:1477. [PMID: 37515164 PMCID: PMC10384018 DOI: 10.3390/v15071477] [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: 05/15/2023] [Revised: 06/14/2023] [Accepted: 06/24/2023] [Indexed: 07/30/2023] Open
Abstract
African swine fever (ASF) is a highly contagious disease that affects wild and domestic swine. Currently, the disease is present as a pandemic affecting pork production in Eurasia and the Caribbean region. The etiological agent of ASF is a large, highly complex structural virus (ASFV) harboring a double-stranded genome encoding for more than 160 proteins whose functions, in most cases, have not been experimentally characterized. We show here that deletion of the ASFV gene H240R from the genome of the highly virulent ASFV-Georgia2010 (ASFV-G) isolate partially decreases virus virulence when experimentally inoculated in domestic swine. ASFV-G-∆H240R, a recombinant virus harboring the deletion of the H240R gene, was produced to evaluate the function of the gene in the development of disease in pigs. While all animals intramuscularly inoculated with 102 HAD50 of ASFV-G developed a fatal form of the disease, forty percent of pigs receiving a similar dose of ASFV-G-∆H240R survived the infection, remaining healthy during the 28-day observational period, and the remaining sixty percent developed a protracted but fatal form of the disease compared to that induced by ASFV-G. Additionally, all animals inoculated with ASFV-G-∆H240R presented protracted viremias with reduced virus titers when compared with those found in animals inoculated with ASFV-G. Animals surviving infection with ASFV-G-∆H240R developed a strong virus-specific antibody response and were protected against the challenge of the virulent parental ASFV-G.
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Affiliation(s)
| | - Ayushi Rai
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
- Oak Ridge Institute for Science and Education, Oak Ridge, TN 37830, USA
| | - Nallely Espinoza
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - Alyssa Valladares
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
- Oak Ridge Institute for Science and Education, Oak Ridge, TN 37830, USA
| | - Ediane Silva
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | | | - Manuel V Borca
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - Douglas P Gladue
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
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20
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Borca MV, Ramirez-Medina E, Silva E, Rai A, Espinoza N, Velazquez-Salinas L, Gladue DP. ASF Vaccine Candidate ASFV-G-∆I177L Does Not Exhibit Residual Virulence in Long-Term Clinical Studies. Pathogens 2023; 12:805. [PMID: 37375495 DOI: 10.3390/pathogens12060805] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/02/2023] [Accepted: 06/04/2023] [Indexed: 06/29/2023] Open
Abstract
African swine fever (ASF) is an important disease in swine currently producing a pandemic affecting pig production worldwide. Except in Vietnam, where two vaccines were recently approved for controlled use in the field, no vaccine is commercially available for disease control. Up to now, the most effective vaccines developed are based on the use of live-attenuated viruses. Most of these promising vaccine candidates were developed by deleting virus genes involved in the process of viral pathogenesis and disease production. Therefore, these vaccine candidates were developed via the genomic modification of parental virus field strains, producing recombinant viruses and reducing or eliminating their residual virulence. In this scenario, it is critical to confirm the absence of any residual virulence in the vaccine candidate. This report describes the assessment of the presence of residual virulence in the ASFV vaccine candidate ASFV-G-∆I177L in clinical studies conducted under high virus loads and long-term observation periods. The results demonstrated that domestic pigs intramuscularly inoculated with 106 HAD50 of ASFV-G-∆I177L did not show the presence of any clinical sign associated with ASF when observed daily either 90 or 180 days after vaccination. In addition, necropsies conducted at the end of the experiment confirmed the absence of macroscopic internal lesions associated with the disease. These results corroborate the safety of using ASFV-G-∆I177L as a vaccine candidate.
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Affiliation(s)
- Manuel V Borca
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | | | - Ediane Silva
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - Ayushi Rai
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Nallely Espinoza
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | | | - Douglas P Gladue
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
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Qi X, Feng T, Ma Z, Zheng L, Liu H, Shi Z, Shen C, Li P, Wu P, Ru Y, Li D, Zhu Z, Tian H, Wu S, Zheng H. Deletion of DP148R, DP71L, and DP96R Attenuates African Swine Fever Virus, and the Mutant Strain Confers Complete Protection against Homologous Challenges in Pigs. J Virol 2023; 97:e0024723. [PMID: 37017515 PMCID: PMC10134827 DOI: 10.1128/jvi.00247-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 03/10/2023] [Indexed: 04/06/2023] Open
Abstract
The African swine fever virus (ASFV) has caused a devastating pandemic in domestic and wild swine, causing economic losses to the global swine industry. Recombinant live attenuated vaccines are an attractive option for ASFV treatment. However, safe and effective vaccines against ASFV are still scarce, and more high-quality experimental vaccine strains need to be developed. In this study, we revealed that deletion of the ASFV genes DP148R, DP71L, and DP96R from the highly virulent isolate ASFV CN/GS/2018 (ASFV-GS) substantially attenuated virulence in swine. Pigs infected with 104 50% hemadsorbing doses of the virus with these gene deletions remained healthy during the 19-day observation period. No ASFV infection was detected in contact pigs under the experimental conditions. Importantly, the inoculated pigs were protected against homologous challenges. Additionally, RNA sequence analysis showed that deletion of these viral genes induced significant upregulation of the host histone H3.1 gene (H3.1) and downregulation of the ASFV MGF110-7L gene. Knocking down the expression of H3.1 resulted in high levels of ASFV replication in primary porcine macrophages in vitro. These findings indicate that the deletion mutant virus ASFV-GS-Δ18R/NL/UK is a novel potential live attenuated vaccine candidate and one of the few experimental vaccine strains reported to induce full protection against the highly virulent ASFV-GS virus strain. IMPORTANCE Ongoing outbreaks of African swine fever (ASF) have considerably damaged the pig industry in affected countries. Thus, a safe and effective vaccine is important to control African swine fever spread. Here, an ASFV strain with three gene deletions was developed by knocking out the viral genes DP148R (MGF360-18R), NL (DP71L), and UK (DP96R). The results showed that the recombinant virus was completely attenuated in pigs and provided strong protection against parental virus challenge. Additionally, no viral genomes were detected in the sera of pigs housed with animals infected with the deletion mutant. Furthermore, transcriptome sequencing (RNA-seq) analysis revealed significant upregulation of histone H3.1 in virus-infected macrophage cultures and downregulation of the ASFV MGF110-7L gene after viral DP148R, UK, and NL deletion. Our study provides a valuable live attenuated vaccine candidate and potential gene targets for developing strategies for anti-ASFV treatment.
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Affiliation(s)
- Xiaolan Qi
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Tao Feng
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Zhao Ma
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Linlin Zheng
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Huanan Liu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Zhengwang Shi
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Chaochao Shen
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Pan Li
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Panxue Wu
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Yi Ru
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Dan Li
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Zixiang Zhu
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Hong Tian
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Sen Wu
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Haixue Zheng
- State Key Laboratory for Animal Disease Control and Prevention, College of Veterinary Medicine, Lanzhou University, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
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22
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Zhou X, Fan J, Zhang Y, Yang J, Zhu R, Yue H, Qi Y, Li Q, Wang Y, Chen T, Zhang S, Hu R. Evaluation of African Swine Fever Virus E111R Gene on Viral Replication and Porcine Virulence. Viruses 2023; 15:v15040890. [PMID: 37112870 PMCID: PMC10143872 DOI: 10.3390/v15040890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 03/13/2023] [Accepted: 03/28/2023] [Indexed: 03/31/2023] Open
Abstract
African swine fever (ASF) is an acute infectious disease of domestic pigs and wild boars caused by the African swine fever virus (ASFV), with up to a 100% case fatality rate. The development of a vaccine for ASFV is hampered by the fact that the function of many genes in the ASFV genome still needs to be discovered. In this study, the previously unreported E111R gene was analyzed and identified as an early-expressed gene that is highly conserved across the different genotypes of ASFV. To further explore the function of the E111R gene, a recombinant strain, SY18ΔE111R, was constructed by deleting the E111R gene of the lethal ASFV SY18 strain. In vitro, the replication kinetics of SY18ΔE111R with deletion of the E111R gene were consistent with those of the parental strain. In vivo, high-dose SY18ΔE111R (105.0 TCID50), administered intramuscularly to pigs, caused the same clinical signs and viremia as the parental strain (102.0 TCID50), with all pigs dying on days 8–11. After being infected with a low dose of SY18ΔE111R (102.0 TCID50) intramuscularly, pigs showed a later onset of disease and 60% mortality, changing from acute to subacute infection. In summary, deletion of the E111R gene has a negligible effect on the lethality of ASFV and does not affect the viruses’ ability to replicate, suggesting that E111R could not be the priority target of ASFV live-attenuated vaccine candidates.
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23
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Zheng N, Li C, Hou H, Chen Y, Zhang A, Han S, Wan B, Wu Y, He H, Wang N, Du Y. A Novel Linear B-Cell Epitope on the P54 Protein of African Swine Fever Virus Identified Using Monoclonal Antibodies. Viruses 2023; 15:v15040867. [PMID: 37112846 PMCID: PMC10142506 DOI: 10.3390/v15040867] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 03/30/2023] Open
Abstract
The African swine fever virus (ASFV) is a highly infectious viral pathogen that presents a major threat to the global pig industry. No effective vaccine is available for the virus. The p54 protein, a major structural component of ASFV, is involved in virus adsorption and entry to target cells and also plays a key role in ASFV vaccine development and disease prevention. Here, we generated species-specific monoclonal antibodies (mAbs), namely 7G10A7F7, 6E8G8E1, 6C3A6D12, and 8D10C12C8 (subtype IgG1/kappa type), against the ASFV p54 protein and characterized the specificity of these mAbs. Peptide scanning techniques were used to determine the epitopes that are recognized by the mAbs, which defined a new B-cell epitope, TMSAIENLR. Amino acid sequence comparison showed that this epitope is conserved among all reference ASFV strains from different regions of China, including the widely prevalent, highly pathogenic strain Georgia 2007/1 (NC_044959.2). This study reveals important signposts for the design and development of ASFV vaccines and also provides critical information for the functional studies of the p54 protein via deletion analysis.
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24
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Zhou X, Fan J, Guo X, Chen T, Yang J, Zhang Y, Mi L, Zhang F, Miao F, Li M, Hu R. Comparison of Genotype II African Swine Fever Virus Strain SY18 Challenge Models. Viruses 2023; 15:v15040858. [PMID: 37112838 PMCID: PMC10142125 DOI: 10.3390/v15040858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/23/2023] [Accepted: 03/27/2023] [Indexed: 03/30/2023] Open
Abstract
African swine fever (ASF) is a viral haemorrhagic disease found in domestic and wild boars caused by the African swine fever virus (ASFV). A highly virulent strain was used to evaluate the efficacy of newly developed vaccine candidates. The ASFV strain SY18 was isolated from the first ASF case in China and is virulent in pigs of all ages. To evaluate the pathogenesis of ASFV SY18 following intraoral (IO) and intranasal (IN) infections, a challenge trial was conducted in landrace pigs, with intramuscular (IM) injection as a control. The results showed that the incubation period of IN administration with 40–1000 50 % tissue culture infective dose (TCID50) was 5–8 days, which was not significantly different from that of IM inoculation with 200 TCID50. A significantly longer incubation period, 11–15 days, was observed in IO administration with 40–5000 TCID50. Clinical features were similar among all infected animals. Symptoms, including high fever (≥40.5 °C), anorexia, depression, and recumbency, were observed. No significant differences were detected in the duration of viral shedding during fever. There was no significant difference in disease outcome, and all animals succumbed to death. This trial showed that IN and IO infections could be used for the efficacy evaluation of an ASF vaccine. The IO infection model, similar to that of natural infection, is highly recommended, especially for the primary screening of candidate vaccine strains or vaccines with relatively weak immune efficacy, such as live vector vaccines and subunit vaccines.
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Affiliation(s)
- Xintao Zhou
- College of Life Sciences, Ningxia University, Yinchuan 750021, China
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Changchun 130122, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China
| | - Jiaqi Fan
- College of Life Sciences, Ningxia University, Yinchuan 750021, China
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Changchun 130122, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China
| | - Xiaopan Guo
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Changchun 130122, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China
| | - Teng Chen
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Changchun 130122, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China
| | - Jinjin Yang
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Changchun 130122, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China
| | - Yanyan Zhang
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Changchun 130122, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China
| | - Lijuan Mi
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Changchun 130122, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China
| | - Fei Zhang
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Changchun 130122, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China
| | - Faming Miao
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Changchun 130122, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China
| | - Min Li
- College of Life Sciences, Ningxia University, Yinchuan 750021, China
- Correspondence: (M.L.); (R.H.)
| | - Rongliang Hu
- College of Life Sciences, Ningxia University, Yinchuan 750021, China
- Key Laboratory of Prevention & Control for African Swine Fever and Other Major Pig Diseases, Ministry of Agriculture and Rural Affairs, Changchun 130122, China
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China
- Correspondence: (M.L.); (R.H.)
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25
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Li Y, Sun R, Li S, Tan Z, Li Z, Liu Y, Guo Y, Huang J. ASFV proteins presented at the surface of T7 phages induce strong antibody responses in mice. J Virol Methods 2023; 316:114725. [PMID: 36965632 DOI: 10.1016/j.jviromet.2023.114725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 03/27/2023]
Abstract
African swine fever virus (ASFV) infection causes substantial economic losses to the swine industry worldwide, and there are still no safe and effective vaccines or therapeutics available. The granulated virus antigen improves the antigen present process and elicits high antibody reaction than the subunit antigen. In this study, the SpyTag peptide-p10 fusion protein was altered and displayed on the surface of the T7 phage to construct an engineered phage (T7-ST). At the same time, ASFV antigen-Spycatcher C-terminal-fused protein (antigen-SC) was expressed and purified by an E. coli prokaryotic expression system. Five virus-like particles (VLPs) displaying the main ASFV antigenic proteins P30, P54, P72, CD2v, and K145R were reconstructed by the isopeptide bond between SpyTag and antigen-SC proteins. The stability of five ASFV VLPs in high temperature and extreme pH conditions was evaluated by transmission electron microscopy (TEM) and plaque analysis. All ASFV VLPs induced a high titer antigen-specific antibody response in mice. Our results showed that the granulated antigen displaying ASFV protein on the surface of the T7 phage provides a robust potential vaccine and diagnostic tool to address the challenge of the ASFV pandemic.
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Affiliation(s)
- Yuanfang Li
- School of Life Sciences, Tianjin University, Tianjin, China, 300072
| | - Ruiqi Sun
- School of Life Sciences, Tianjin University, Tianjin, China, 300072
| | - Shujun Li
- School of Life Sciences, Tianjin University, Tianjin, China, 300072
| | - Zheng Tan
- School of Life Sciences, Tianjin University, Tianjin, China, 300072
| | - Zexing Li
- School of Life Sciences, Tianjin University, Tianjin, China, 300072
| | - Yebin Liu
- China Institute of Veterinary Drug Control, Beijing, China, 100081
| | - Yanyu Guo
- School of Life Sciences, Tianjin University, Tianjin, China, 300072.
| | - Jinhai Huang
- School of Life Sciences, Tianjin University, Tianjin, China, 300072.
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Ramirez-Medina E, Vuono EA, Rai A, Espinoza N, Valladares A, Spinard E, Velazquez-Salinas L, Gladue DP, Borca MV. Evaluation of the Function of ASFV Gene E66L in the Process of Virus Replication and Virulence in Swine. Viruses 2023; 15:v15020566. [PMID: 36851779 PMCID: PMC9965554 DOI: 10.3390/v15020566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 02/12/2023] [Accepted: 02/13/2023] [Indexed: 02/22/2023] Open
Abstract
African swine fever virus (ASFV) is the etiological agent of an economically important disease of swine currently affecting large areas of Africa, Eurasia and the Caribbean. ASFV has a complex structure harboring a large dsDNA genome which encodes for more than 160 proteins. One of the proteins, E66L, has recently been involved in arresting gene transcription in the infected host cell. Here, we investigate the role of E66L in the processes of virus replication in swine macrophages and disease production in domestic swine. A recombinant ASFV was developed (ASFV-G-∆E66L), from the virulent parental Georgia 2010 isolate (ASFV-G), harboring the deletion of the E66L gene as a tool to assess the role of the gene. ASFV-G-∆E66L showed that the E66L gene is non-essential for ASFV replication in primary swine macrophages when compared with the parental highly virulent field isolate ASFV-G. Additionally, domestic pigs infected with ASFV-G-∆E66L developed a clinical disease undistinguishable from that produced by ASFV-G. Therefore, E66L is not involved in virus replication or virulence in domestic pigs.
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Affiliation(s)
- Elizabeth Ramirez-Medina
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA
| | - Elizabeth A. Vuono
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA
| | - Ayushi Rai
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Nallely Espinoza
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA
| | - Alyssa Valladares
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Edward Spinard
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA
| | - Lauro Velazquez-Salinas
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA
| | - Douglas P. Gladue
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA
- Correspondence: (D.P.G.); (M.V.B.)
| | - Manuel V. Borca
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA
- Correspondence: (D.P.G.); (M.V.B.)
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27
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Zhang H, Zhao S, Zhang H, Qin Z, Shan H, Cai X. Vaccines for African swine fever: an update. Front Microbiol 2023; 14:1139494. [PMID: 37180260 PMCID: PMC10173882 DOI: 10.3389/fmicb.2023.1139494] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 04/05/2023] [Indexed: 05/16/2023] Open
Abstract
African swine fever (ASF) is a fatal infectious disease of swine caused by the African swine fever virus (ASFV). Currently, the disease is listed as a legally notifiable disease that must be reported to the World Organization for Animal Health (WOAH). The economic losses to the global pig industry have been insurmountable since the outbreak of ASF. Control and eradication of ASF are very critical during the current pandemic. Vaccination is the optimal strategy to prevent and control the ASF epidemic, but since inactivated ASFV vaccines have poor immune protection and there aren't enough cell lines for efficient in vitro ASFV replication, an ASF vaccine with high immunoprotective potential still remains to be explored. Knowledge of the course of disease evolution, the way of virus transmission, and the breakthrough point of vaccine design will facilitate the development of an ASF vaccine. In this review, the paper aims to highlight the recent advances and breakthroughs in the epidemic and transmission of ASF, virus mutation, and the development of vaccines in recent years, focusing on future directions and trends.
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Affiliation(s)
- Hongliang Zhang
- Shandong Collaborative Innovation Center for Development of Veterinary Pharmaceuticals, College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, China
| | - Saisai Zhao
- Shandong Collaborative Innovation Center for Development of Veterinary Pharmaceuticals, College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, China
- College of Animal Science and Technology, Shandong Agricultural University, Tai’an, China
| | - Haojie Zhang
- Shandong Collaborative Innovation Center for Development of Veterinary Pharmaceuticals, College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, China
| | - Zhihua Qin
- Shandong Collaborative Innovation Center for Development of Veterinary Pharmaceuticals, College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, China
| | - Hu Shan
- Shandong Collaborative Innovation Center for Development of Veterinary Pharmaceuticals, College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, China
- *Correspondence: Hu Shan,
| | - Xiulei Cai
- Shandong Collaborative Innovation Center for Development of Veterinary Pharmaceuticals, College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, China
- Xiulei Cai,
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28
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Lv T, Xie X, Song N, Zhang S, Ding Y, Liu K, Diao L, Chen X, Jiang S, Li T, Zhang W, Cao Y. Expounding the role of tick in Africa swine fever virus transmission and seeking effective prevention measures: A review. Front Immunol 2022; 13:1093599. [PMID: 36591310 PMCID: PMC9800779 DOI: 10.3389/fimmu.2022.1093599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
African swine fever (ASF), a highly contagious, deadly infectious disease, has caused huge economic losses to animal husbandry with a 100% mortality rate of the most acute and acute infection, which is listed as a legally reported animal disease by the World Organization for Animal Health (OIE). African swine fever virus (ASFV) is the causative agent of ASF, which is the only member of the Asfarviridae family. Ornithodoros soft ticks play an important role in ASFV transmission by active biological or mechanical transmission or by passive transport or ingestion, particularly in Africa, Europe, and the United States. First, this review summarized recent reports on (1) tick species capable of transmitting ASFV, (2) the importance of ticks in the transmission and epidemiological cycle of ASFV, and (3) the ASFV strains of tick transmission, to provide a detailed description of tick-borne ASFV. Second, the dynamics of tick infection with ASFV and the tick-induced immune suppression were further elaborated to explain how ticks spread ASFV. Third, the development of the anti-tick vaccine was summarized, and the prospect of the anti-tick vaccine was recapitulated. Then, the marked attenuated vaccine, ASFV-G-ΔI177L, was compared with those of the anti-tick vaccine to represent potential therapeutic or strategies to combat ASF.
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Affiliation(s)
- Tianbao Lv
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xufeng Xie
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Ning Song
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Shilei Zhang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Yue Ding
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Kun Liu
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Luteng Diao
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Xi Chen
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Shuang Jiang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Tiger Li
- Portsmouth Abbey School, Portsmouth, RI, United States
| | - Wenlong Zhang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China,Key Laboratory for Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China,*Correspondence: Yongguo Cao, ; Wenlong Zhang,
| | - Yongguo Cao
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, China,Key Laboratory for Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China,*Correspondence: Yongguo Cao, ; Wenlong Zhang,
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29
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McDowell CD, Bold D, Trujillo JD, Meekins DA, Keating C, Cool K, Kwon T, Madden DW, Artiaga BL, Balaraman V, Ankhanbaatar U, Zayat B, Retallick J, Dodd K, Chung CJ, Morozov I, Gaudreault NN, Souza-Neto JA, Richt JA. Experimental Infection of Domestic Pigs with African Swine Fever Virus Isolated in 2019 in Mongolia. Viruses 2022; 14:v14122698. [PMID: 36560702 PMCID: PMC9781604 DOI: 10.3390/v14122698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/23/2022] [Accepted: 11/24/2022] [Indexed: 12/03/2022] Open
Abstract
African swine fever (ASF) is an infectious viral disease caused by African swine fever virus (ASFV), that causes high mortality in domestic swine and wild boar (Sus scrofa). Currently, outbreaks are mitigated through strict quarantine measures and the culling of affected herds, resulting in massive economic losses to the global pork industry. In 2019, an ASFV outbreak was reported in Mongolia, describing a rapidly progressing clinical disease and gross lesions consistent with the acute form of ASF; the virus was identified as a genotype II virus. Due to the limited information on clinical disease and viral dynamics within hosts available from field observations of the Mongolian isolates, we conducted the present study to further evaluate the progression of clinical disease, virulence, and pathology of an ASFV Mongolia/2019 field isolate (ASFV-MNG19), by experimental infection of domestic pigs. Intramuscular inoculation of domestic pigs with ASFV-MNG19 resulted in clinical signs and viremia at 3 days post challenge (DPC). Clinical disease rapidly progressed, resulting in the humane euthanasia of all pigs by 7 DPC. ASFV-MNG19 infected pigs had viremic titers of 108 TCID50/mL by 5 DPC and shed virus in oral secretions late in disease, as determined from oropharyngeal swabs. Whole-genome sequencing confirmed that the ASFV-MNG19 strain used in this study was a genotype II strain highly similar to other regional strains. In conclusion, we demonstrate that ASFV-MNG19 is a virulent genotype II ASFV strain that causes acute ASF in domestic swine.
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Affiliation(s)
- Chester D. McDowell
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Dashzeveg Bold
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Jessie D. Trujillo
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - David A. Meekins
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Cassidy Keating
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Konner Cool
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Taeyong Kwon
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Daniel W. Madden
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Bianca L. Artiaga
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Velmurugan Balaraman
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | | | - Batsukh Zayat
- Institute of Veterinary Medicine, Mongolian University of Life Science, Ulaanbaatar 17024, Mongolia
| | - Jamie Retallick
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Kimberly Dodd
- Veterinary Diagnostic Laboratory, College of Veterinary Medicine, Michigan State University, Lansing, MI 48824, USA
| | - Chungwon J. Chung
- Proficiency and Validation Service Section, Foreign Animal Disease Diagnostic Laboratory, Animal and Plant Health Inspection Services, United States Department of Agriculture, Plum Island Animal Disease Center, Greenport, NY 11944, USA
| | - Igor Morozov
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Natasha N. Gaudreault
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Jayme A. Souza-Neto
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Jürgen A. Richt
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
- Correspondence:
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30
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Attreed SE, Silva C, Abbott S, Ramirez-Medina E, Espinoza N, Borca MV, Gladue DP, Diaz-San Segundo F. A Highly Effective African Swine Fever Virus Vaccine Elicits a Memory T Cell Response in Vaccinated Swine. Pathogens 2022; 11:pathogens11121438. [PMID: 36558773 PMCID: PMC9783822 DOI: 10.3390/pathogens11121438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 11/17/2022] [Accepted: 11/24/2022] [Indexed: 12/03/2022] Open
Abstract
African Swine Fever Virus (ASFV) is the causative agent of a highly contagious and lethal vector-borne disease in suids. Recently, a live attenuated virus strain, developed using the currently circulating, virulent Georgia strain (ASFV-G) with a single gene deletion (ASFV-G-ΔI177L), resulted in an effective vaccine. Nevertheless, protective immune response mechanisms induced by this candidate are poorly understood. In this study, Yorkshire crossbred swine intramuscularly vaccinated with 106 50% hemadsorption dose (HAD50) of ASFV-G-ΔI177L or a vehicle control were challenged at 28 days post-inoculation (dpi) with 102 HAD50 of ASFV-G. Analysis of purified peripheral blood mononuclear cells following inoculation and challenge revealed that CD4+, CD8+ and CD4+CD8+ central memory T cells (CD44+CD25-CD27-CD62L+CCR7+, Tcm) decreased significantly by 28 dpi in ASFV-G-ΔI177L-vaccinated swine compared to baseline and time-matched controls. Conversely, CD4+, CD8+ and CD4+CD8+ effector memory T cells (CD44+CD25-CD27-CD62-CCR7-, Tem) increased significantly among ASFV-G-ΔI177L-vaccined swine by 28 dpi compared to baseline and time-matched controls. Additionally, the percentage of natural killer (NK), CD4+ and CD4+CD8+ Tem and CD8+ Tcm and Tem positive for IFNγ increased significantly following inoculation, surpassing that of controls by 28 dpi or earlier. These results suggest that NK and memory T cells play a role in protective immunity and suggest that studying these cell populations may be a surrogate immunity marker in ASF vaccination.
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Affiliation(s)
- Sarah E. Attreed
- U.S. Department of Agriculture, Agricultural Research Service, Plum Island Animal Disease Center, Greenport, New York, NY 11944, USA
- PIADC Research Participation Program, Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Christina Silva
- U.S. Department of Agriculture, Agricultural Research Service, Plum Island Animal Disease Center, Greenport, New York, NY 11944, USA
| | - Sophia Abbott
- U.S. Department of Agriculture, Agricultural Research Service, Plum Island Animal Disease Center, Greenport, New York, NY 11944, USA
| | - Elizabeth Ramirez-Medina
- U.S. Department of Agriculture, Agricultural Research Service, Plum Island Animal Disease Center, Greenport, New York, NY 11944, USA
| | - Nallely Espinoza
- U.S. Department of Agriculture, Agricultural Research Service, Plum Island Animal Disease Center, Greenport, New York, NY 11944, USA
| | - Manuel V. Borca
- U.S. Department of Agriculture, Agricultural Research Service, Plum Island Animal Disease Center, Greenport, New York, NY 11944, USA
- Correspondence: (M.V.B.); (D.P.G.); (F.D.-S.S.); Tel.: +1-(631)-323-3131 (M.V.B.); +1-(631)-323-3035 (D.P.G.); +1-(631)-323-3012 (F.D.-S.S.)
| | - Douglas P. Gladue
- U.S. Department of Agriculture, Agricultural Research Service, Plum Island Animal Disease Center, Greenport, New York, NY 11944, USA
- Correspondence: (M.V.B.); (D.P.G.); (F.D.-S.S.); Tel.: +1-(631)-323-3131 (M.V.B.); +1-(631)-323-3035 (D.P.G.); +1-(631)-323-3012 (F.D.-S.S.)
| | - Fayna Diaz-San Segundo
- U.S. Department of Agriculture, Agricultural Research Service, Plum Island Animal Disease Center, Greenport, New York, NY 11944, USA
- Correspondence: (M.V.B.); (D.P.G.); (F.D.-S.S.); Tel.: +1-(631)-323-3131 (M.V.B.); +1-(631)-323-3035 (D.P.G.); +1-(631)-323-3012 (F.D.-S.S.)
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31
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Brake DA. African Swine Fever Modified Live Vaccine Candidates: Transitioning from Discovery to Product Development through Harmonized Standards and Guidelines. Viruses 2022; 14:2619. [PMID: 36560623 PMCID: PMC9788307 DOI: 10.3390/v14122619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/20/2022] [Accepted: 11/21/2022] [Indexed: 11/25/2022] Open
Abstract
The recent centennial anniversary of R.E. Montgomery's seminal published description of "a form of swine fever" disease transmitted from wild African pigs to European domestic pigs is a call to action to accelerate African Swine Fever (ASF) vaccine research and development. ASF modified live virus (MLV) first-generation gene deleted vaccine candidates currently offer the most promise to meet international and national guidelines and regulatory requirements for veterinary product licensure and market authorization. A major, rate-limiting impediment to the acceleration of current as well as future vaccine candidates into regulatory development is the absence of internationally harmonized standards for assessing vaccine purity, potency, safety, and efficacy. This review summarizes the asymmetrical landscape of peer-reviewed published literature on ASF MLV vaccine approaches and lead candidates, primarily studied to date in the research laboratory in proof-of-concept or early feasibility clinical safety and efficacy studies. Initial recommendations are offered toward eventual consensus of international harmonized guidelines and standards for ASF MLV vaccine purity, potency, safety, and efficacy. To help ensure the successful regulatory development and approval of ASF MLV first generation vaccines by national regulatory associated government agencies, the World Organisation for Animal Health (WOAH) establishment and publication of harmonized international guidelines is paramount.
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Affiliation(s)
- David A Brake
- BioQuest Associates, LLC, P.O. Box 787, Stowe, VT 05672, USA
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32
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Deletion of an African Swine Fever Virus ATP-Dependent RNA Helicase QP509L from the Highly Virulent Georgia 2010 Strain Does Not Affect Replication or Virulence. Viruses 2022; 14:v14112548. [PMID: 36423157 PMCID: PMC9694930 DOI: 10.3390/v14112548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 10/31/2022] [Accepted: 11/08/2022] [Indexed: 11/19/2022] Open
Abstract
African swine fever virus (ASFV) produces a lethal disease (ASF) in domestic pigs, which is currently causing a pandemic deteriorating pig production across Eurasia. ASFV is a large and structurally complex virus with a large genome harboring more than 150 genes. ASFV gene QP509L has been shown to encode for an ATP-dependent RNA helicase, which appears to be important for efficient virus replication. Here, we report the development of a recombinant virus, ASFV-G-∆QP509L, having deleted the QP509L gene in the highly virulent field isolate ASFV Georgia 2010 (ASFV-G). It is shown that ASFV-G-∆QP509L replicates in primary swine macrophage cultures as efficiently as the parental virus ASFV-G. In addition, the experimental inoculation of pigs with 102 HAD50 by the intramuscular route produced a slightly protracted but lethal clinical disease when compared to that of animals inoculated with virulent parental ASFV-G. Viremia titers in animals infected with ASFV-G-∆QP509L also had slightly protracted kinetics of presentation. Therefore, ASFV gene QP509L is not critical for the processes of virus replication in swine macrophages, nor is it clearly involved in virus replication and virulence in domestic pigs.
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33
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Silva EB, Krug PW, Ramirez-Medina E, Valladares A, Rai A, Espinoza N, Gladue DP, Borca MV. The Presence of Virus Neutralizing Antibodies Is Highly Associated with Protection against Virulent Challenge in Domestic Pigs Immunized with ASFV live Attenuated Vaccine Candidates. Pathogens 2022; 11:1311. [PMID: 36365062 PMCID: PMC9694691 DOI: 10.3390/pathogens11111311] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 11/03/2022] [Accepted: 11/05/2022] [Indexed: 10/29/2023] Open
Abstract
African swine fever virus (ASFV) is currently producing a pandemic affecting a large area of Eurasia, and more recently, the Dominican Republic in the Western Hemisphere. ASFV is a large and structurally complex virus with a large dsDNA genome encoding for more than 150 genes. Live attenuated virus strains can induce protection in domestic swine against disease produced by homologous virulent parental viruses. The roles of the different immune mechanisms induced by the attenuated strains in protection still need to be understood. In particular, the role of ASFV neutralizing antibody in protection still is an important controversial issue to be elucidated. Here we present the development of a novel methodology to detect virus neutralizing antibodies based on the reduction of virus infectivity in a Vero cell adapted ASFV strain. The described method was used to assess levels of virus neutralizing antibodies in domestic swine inoculated with live attenuated ASFV. Results demonstrated a high association between the presence of virus neutralizing antibodies and protection in 84 animals immunized with the recombinant vaccine candidates ASFV-G-Δ9GL/ΔUK or ASFV-G-ΔI177L. To our knowledge, this is the first report demonstrating an association between virus neutralizing antibodies and protection against virulent challenge in such a large number of experimental individuals.
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Affiliation(s)
- Ediane B. Silva
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - Peter W. Krug
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | | | - Alyssa Valladares
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
- College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Ayushi Rai
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Nallely Espinoza
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - Douglas P. Gladue
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - Manuel V. Borca
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
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34
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Ruiz-Saenz J, Diaz A, Bonilla-Aldana DK, Rodríguez-Morales AJ, Martinez-Gutierrez M, Aguilar PV. African swine fever virus: A re-emerging threat to the swine industry and food security in the Americas. Front Microbiol 2022; 13:1011891. [PMID: 36274746 PMCID: PMC9581234 DOI: 10.3389/fmicb.2022.1011891] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 09/16/2022] [Indexed: 12/15/2022] Open
Affiliation(s)
- Julian Ruiz-Saenz
- Grupo de Investigación en Ciencias Animales—GRICA, Universidad Cooperativa de Colombia, Bucaramanga, Colombia,*Correspondence: Julian Ruiz-Saenz ;
| | - Andres Diaz
- PIC—Pig Improvement Company, Querétaro, Mexico
| | - D. Katterine Bonilla-Aldana
- Grupo de Investigación Biomedicina, Faculty of Medicine, Fundación Universitaria Autónoma de las Américas, Pereira, Colombia
| | - Alfonso J. Rodríguez-Morales
- Grupo de Investigación Biomedicina, Faculty of Medicine, Fundación Universitaria Autónoma de las Américas, Pereira, Colombia,Faculty of Health Sciences, Universidad Cientifica del Sur, Lima, Peru
| | - Marlen Martinez-Gutierrez
- Grupo de Investigación en Microbiología Veterinaria, Escuela de Microbiología, Universidad de Antioquia, Medellín, Colombia
| | - Patricia V. Aguilar
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, United States,Center for Tropical Diseases, Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, TX, United States
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35
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Li X, Li Y, Fan M, Fan S, Gao W, Ren J, Liu Q, Li J, Wu W, Li J, Yu Q, Wang X, Yan Z. Inguinal lymph node sample collected by minimally invasive sampler helps to accurately diagnose ASF in dead pigs without necropsy. Front Vet Sci 2022; 9:1000969. [PMID: 36246330 PMCID: PMC9554536 DOI: 10.3389/fvets.2022.1000969] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 08/30/2022] [Indexed: 11/13/2022] Open
Abstract
African swine fever (ASF) is a highly contagious hemorrhagic and transboundary animal disease, and it threatens global food security. A full necropsy to harvest the sample matrices for diagnosis in the farm may lead to contamination of the premises and directly threaten to the herds. In the present study, we compared the ASFV loads of the common samples that can be collected without necropsy. The unmatched nasal, throat, rectal samples were randomly taken using cotton swabs, and inguinal lymph node samples were collected by the minimally invasive samplers from the dead pigs of an ASF field outbreak farm. The ASFV loads of the samples were detected by qPCR and the results suggested that the overall ASFV nucleic acids levels of inguinal lymph node samples were higher than the swabs. What's more, sets of matched nasal swabs, rectal swabs, throat swabs, inguinal lymph nodes, serums, spleens and lungs samples were collected from 15 dead ASFV naturally infected pigs. Similarly, the results showed that inguinal lymph node samples, together with serum, spleen and lungs samples, contained more ASFV nucleic acids than the swabs. Our findings demonstrated that the inguinal lymph node collected by minimally invasive sampler is an ideal tissue for diagnosing ASFV infection in dead pigs without necropsy.
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Affiliation(s)
- Xiaowen Li
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd., (NHLH Academy Swine Research), Dezhou, China
- Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd., Dezhou, China
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Yang Li
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd., (NHLH Academy Swine Research), Dezhou, China
- New Hope Liuhe Co., Ltd., Chengdu, China
| | - Mingyu Fan
- Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd., Dezhou, China
| | - Shiran Fan
- New Hope Liuhe Co., Ltd., Chengdu, China
| | - Wenchao Gao
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd., (NHLH Academy Swine Research), Dezhou, China
| | - Jing Ren
- Swine Health Data and Intelligent Monitoring Project Laboratory, Dezhou University, Dezhou, China
| | - Qingyuan Liu
- Shandong New Hope Liuhe Agriculture and Animal Husbandry Technology Co., Ltd., (NHLH Academy Swine Research), Dezhou, China
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Jingtao Li
- New Hope Liuhe Co., Ltd., Chengdu, China
| | | | - Junxian Li
- New Hope Liuhe Co., Ltd., Chengdu, China
| | - Qiannan Yu
- Xiajin New Hope Liuhe Agriculture and Animal Husbandry Co., Ltd., Dezhou, China
| | - Xinglong Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
- *Correspondence: Xinglong Wang
| | - Zhichun Yan
- New Hope Liuhe Co., Ltd., Chengdu, China
- Zhichun Yan
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Taking a Promising Vaccine Candidate Further: Efficacy of ASFV-G-ΔMGF after Intramuscular Vaccination of Domestic Pigs and Oral Vaccination of Wild Boar. Pathogens 2022; 11:pathogens11090996. [PMID: 36145428 PMCID: PMC9504512 DOI: 10.3390/pathogens11090996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/29/2022] [Accepted: 08/29/2022] [Indexed: 11/17/2022] Open
Abstract
African swine fever (ASF) is a pandemic threat to the global pig industry and wild suids. A safe and efficacious vaccine could monumentally assist in disease eradication. In the past years, promising live attenuated vaccine candidates emerged in proof-of-concept experiments, among which was “ASFV-G-∆MGF”. In our study, we tested the vaccine candidate in three animal experiments intramuscularly in domestic pigs and orally in wild boar. Further, a macrophage-grown vaccine virus and a virus grown on permanent cells could be employed. Irrespective of the production system of the vaccine virus, a two-dose intramuscular immunization could induce close-to-sterile immunity with full clinical protection against challenge infection. After oral immunization, 50% of the vaccinees seroconverted and all responders were completely protected against subsequent challenge. All nonresponders developed ASF upon challenge with two acute lethal infections and two mild and transient courses. The latter results show a lower efficiency after oral administration that would have to be taken into consideration when designing vaccination-based control measures. Overall, our findings confirm that “ASFV-G-∆MGF” is a most promising vaccine candidate that could find its way into well-organized and controlled immunization campaigns. Further research is needed to characterize safety aspects and define possible improvements of oral efficiency.
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Cao G, Qiu Y, Long K, Xiong Y, MeimeiShi, JunYang, Li Y, Nie F, Huo D, Hou C. Carbon nanodots combined with loop-mediated isothermal amplification (LAMP) for detection of African swine fever virus (ASFV). Mikrochim Acta 2022; 189:342. [PMID: 35997837 PMCID: PMC9396581 DOI: 10.1007/s00604-022-05390-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 06/19/2022] [Indexed: 12/03/2022]
Abstract
The spread of African swine fever virus (ASFV) caused huge economic costs, so early detection is particularly important. Here, we established a fluorescence biosensor based on carbon nanodots (CNDs) and loop-mediated isothermal amplification (LAMP) to ultra-sensitively detect ASFV. LAMP with high efficiency produced a large amount of pyro phosphoric acid and caused pH change in a short time. CNDs with strong light stability had a large fluorescence response at the emission wavelength of 585.5 nm to small pH change by the excitation wavelength of 550 nm. The biosensor realized “turn-off–on” mode for ASFV detection with the detection limit as low as 15.21 copies μL−1. In addition, the biosensor had high accuracy in the actual sample assay. Therefore, the biosensor achieved rapid, sensitive, low-cost, and simple detection for ASFV. Moreover, the biosensor broadened the detection pathway of LAMP as a tool with great development prospect.
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Affiliation(s)
- Gaihua Cao
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China
| | - Yue Qiu
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China
| | - Keyi Long
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China
| | - Yifan Xiong
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China
| | - MeimeiShi
- State Key Laboratory of Cattle Diseases Detection (Chongqing), Chongqing Customs, Chongqing Customs Technology Center, Chongqing, 400020, People's Republic of China
| | - JunYang
- State Key Laboratory of Cattle Diseases Detection (Chongqing), Chongqing Customs, Chongqing Customs Technology Center, Chongqing, 400020, People's Republic of China
| | - Yingguo Li
- State Key Laboratory of Cattle Diseases Detection (Chongqing), Chongqing Customs, Chongqing Customs Technology Center, Chongqing, 400020, People's Republic of China
| | - Fuping Nie
- State Key Laboratory of Cattle Diseases Detection (Chongqing), Chongqing Customs, Chongqing Customs Technology Center, Chongqing, 400020, People's Republic of China.
| | - Danqun Huo
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China. .,Chongqing Key Laboratory of Bio-Perception & Intelligent Information Processing, School of Microelectronics and Communication Engineering, Chongqing University, Chongqing, 400044, People's Republic of China.
| | - Changjun Hou
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, Chongqing, 400044, People's Republic of China.
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Ramirez-Medina E, Vuono E, Pruitt S, Rai A, Espinoza N, Valladares A, Spinard E, Silva E, Velazquez-Salinas L, Gladue DP, Borca MV. ASFV Gene A151R Is Involved in the Process of Virulence in Domestic Swine. Viruses 2022; 14:v14081834. [PMID: 36016456 PMCID: PMC9413758 DOI: 10.3390/v14081834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/10/2022] [Accepted: 08/15/2022] [Indexed: 11/16/2022] Open
Abstract
African swine fever virus (ASFV) is the etiological agent of a swine pandemic affecting a large geographical area extending from Central Europe to Asia. The viral disease was also recently identified in the Dominican Republic and Haiti. ASFV is a structurally complex virus with a large dsDNA genome that encodes for more than 150 genes. Most of these genes have not been experimentally characterized. One of these genes, A151R, encodes for a nonstructural protein and has been reported to be required for the replication of a Vero-cell-adapted ASFV strain. Here, we evaluated the role of the A151R gene in the context of the highly virulent field isolate Georgia 2010 (ASFV-G) during virus replication in swine macrophage cell cultures and during experimental infection in swine. We show that the recombinant virus ASFV-G-∆A151R, harboring a deletion of the A151R gene, replicated in swine macrophage cultures as efficiently as the parental virus ASFV-G, indicating that the A151R gene is not required for ASFV replication in swine macrophages. Interestingly, experimental infection of domestic pigs demonstrated that ASFV-G-∆A151R had a decreased replication rate and produced a drastic reduction in virus virulence. Animals were intramuscularly inoculated with 102 HAD50 of ASFV-G-∆A151R and compared with pigs receiving a similar dose of virulent ASFV-G. All ASFV-G-infected pigs developed an acute lethal form of the disease, while those inoculated with ASFV-G-∆A151R remained healthy during the 28-day observational period, with the exception of only one showing a protracted, but fatal, form of the disease. All ASFV-G-∆A151R surviving animals presented protracted viremias with lower virus titers than those detected in ASFV-G-infected animals. In addition, three out of the four animals surviving the infection with ASFV-G-∆A151R were protected against the challenge with the virulent parental virus ASFV-G. This is the first report indicating that the ASFV A151R gene is involved in virus virulence in domestic swine, suggesting that its deletion may be used to increase the safety profile of currently experimental vaccines.
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Affiliation(s)
| | - Elizabeth Vuono
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
- Department of Pathobiology and Population Medicine, Mississippi State University, P.O. Box 6100, Starkville, MS 39762, USA
| | - Sarah Pruitt
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - Ayushi Rai
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Nallely Espinoza
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - Alyssa Valladares
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Edward Spinard
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | - Ediane Silva
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
| | | | - Douglas P. Gladue
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
- Correspondence: (D.P.G.); (M.V.B.)
| | - Manuel V. Borca
- Plum Island Animal Disease Center, ARS, USDA, Greenport, NY 11944, USA
- Correspondence: (D.P.G.); (M.V.B.)
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Li Z, Chen W, Qiu Z, Li Y, Fan J, Wu K, Li X, Zhao M, Ding H, Fan S, Chen J. African Swine Fever Virus: A Review. LIFE (BASEL, SWITZERLAND) 2022; 12:life12081255. [PMID: 36013434 PMCID: PMC9409812 DOI: 10.3390/life12081255] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 07/29/2022] [Accepted: 07/29/2022] [Indexed: 11/16/2022]
Abstract
African swine fever (ASF) is a viral disease with a high fatality rate in both domestic pigs and wild boars. ASF has greatly challenged pig-raising countries and also negatively impacted regional and national trade of pork products. To date, ASF has spread throughout Africa, Europe, and Asia. The development of safe and effective ASF vaccines is urgently required for the control of ASF outbreaks. The ASF virus (ASFV), the causative agent of ASF, has a large genome and a complex structure. The functions of nearly half of its viral genes still remain to be explored. Knowledge on the structure and function of ASFV proteins, the mechanism underlying ASFV infection and immunity, and the identification of major immunogenicity genes will contribute to the development of an ASF vaccine. In this context, this paper reviews the available knowledge on the structure, replication, protein function, virulence genes, immune evasion, inactivation, vaccines, control, and diagnosis of ASFV.
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Affiliation(s)
- Zhaoyao Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Wenxian Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Zilong Qiu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Yuwan Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Jindai Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Keke Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Xiaowen Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Mingqiu Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Hongxing Ding
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Shuangqi Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Correspondence: (S.F.); (J.C.); Fax: +86-20-8528-0245 (J.C.)
| | - Jinding Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Correspondence: (S.F.); (J.C.); Fax: +86-20-8528-0245 (J.C.)
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40
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Abstract
African swine fever (ASF) is a lethal and highly contagious viral disease of domestic and wild pigs, listed as a notifiable disease reported to the World Organization for Animal Health (OIE). Despite its limited host range and absent zoonotic potential, the socio-economic and environmental impact of ASF is very high, representing a serious threat to the global swine industry and the many stakeholders involved. Currently, only control and eradication measures based mainly on early detection and strict stamping-out policies are available, however, the rapid spread of the disease in new countries, and in new regions in countries already affected, show these strategies to be lacking. In this review, we discuss approaches to ASF vaccinology, with emphasis on the advances made over the last decade, including the development of virulence-associated gene deleted strains such as the very promising ASFV-G-ΔI177L/ΔLVR, that replicates efficiently in a stable porcine epithelial cell line, and the cross-protecting BA71ΔCD2 capable of stably growing in the commercial COS-1 cell line, or the naturally attenuated Lv17/WB/Rie1 which shows solid protection in wild boar. We also consider the key constraints involved in the scale-up and commercialization of promising live attenuated and virus-vectored vaccine candidates, namely cross-protection, safety, lack of suitable animal models, compatibility with wildlife immunization, availability of established and licensed cell lines, and differentiating infected from vaccinated animals (DIVA) strategy.
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Affiliation(s)
- Ana Catarina Urbano
- CIISA - Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon.,Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS)
| | - Fernando Ferreira
- CIISA - Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon.,Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS)
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Deletion of the EP296R Gene from the Genome of Highly Virulent African Swine Fever Virus Georgia 2010 Does Not Affect Virus Replication or Virulence in Domestic Pigs. Viruses 2022; 14:v14081682. [PMID: 36016304 PMCID: PMC9415450 DOI: 10.3390/v14081682] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 07/22/2022] [Accepted: 07/22/2022] [Indexed: 11/29/2022] Open
Abstract
African swine fever virus (ASFV) causes a lethal disease (ASF) in domestic pigs, African swine fever (ASF). ASF is currently producing a pandemic affecting pig production across Eurasia, leading to a shortage of food accessibility. ASFV is structurally complex, harboring a large genome encoding over 150 genes. One of them, EP296R, has been shown to encode for an endonuclease that is necessary for the efficient replication of the virus in swine macrophages, the natural ASFV target cell. Here, we report the development of a recombinant virus, ASFV-G-∆EP296R, harboring the deletion of the EP296R gene from the genome of the highly virulent field isolate ASFV Georgia 2010 (ASFV-G). The recombinant ASFV-G-∆EP296R replicates in primary swine macrophages with similar kinetics as the parental virus ASFV-G. Pigs experimentally infected by the intramuscular route with 102 HAD50 show a slightly protracted, although lethal, presentation of the disease when compared to that of animals inoculated with parental ASFV-G. Viremia titers in the ASFV-G-∆EP296R-infected animals closely followed the kinetics of presentation of clinical disease. Results presented here demonstrate that ASFV-G-∆EP296R is not essential for the processes of ASFV replication in swine macrophages, nor is it radically involved in the process of virus replication or disease production in domestic pigs.
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Evaluation of the Deletion of MGF110-5L-6L on Swine Virulence from the Pandemic Strain of African Swine Fever Virus and Use as a DIVA Marker in Vaccine Candidate ASFV-G-ΔI177L. J Virol 2022; 96:e0059722. [PMID: 35862688 PMCID: PMC9327674 DOI: 10.1128/jvi.00597-22] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
African swine fever virus (ASFV) is responsible for an ongoing pandemic that is affecting central Europe, Asia, and recently the Dominican Republic, the first report of the disease in the Western Hemisphere in over 40 years. ASFV is a large, complex virus with a double-stranded DNA (dsDNA) genome that carries more than 150 genes, most of which have not been studied. Here, we assessed the role of the MGF110-5L-6L gene during virus replication in cell cultures and experimental infection in swine. A recombinant virus with MGF110-5L-6L deleted (ASFV-G-ΔMGF110-5L-6L) was developed using the highly virulent ASFV Georgia (ASFV-G) isolate as a template. ASFV-G-ΔMGF110-5L-6L replicates in swine macrophage cultures as efficiently as the parental virus ASFV-G, indicating that the MGF110-5L-6L gene is nonessential for virus replication. Similarly, domestic pigs inoculated with ASFV-G-ΔMGF110-5L-6L presented with a clinical disease undistinguishable from that caused by the parental ASFV-G, confirming that the MGF110-5L-6L gene is not involved in producing disease in swine. Sera from animals inoculated with an efficacious vaccine candidate, ASFV-G-ΔMGF, strongly recognized the protein encoded by the MGF110-5L-6L gene as a potential target for the development of an antigenic marker differentiation of infected from vaccinated animals (DIVA) vaccine. To test this hypothesis, the MGF110-5L-6L gene was deleted from the highly efficacious ASFV vaccine candidate ASFV-G-ΔI177L, generating the recombinant ASFV-G-ΔI177L/ΔMGF110-5L-6L. Animals inoculated with ASFV-G-ΔI177L/ΔMGF110-5L-6L developed an ASFV-specific antibody response detected by enzyme-linked immunosorbent assay (ELISA). The sera strongly recognized ASFV p30 expressed in eukaryotic cells but did not recognize ASFV MGF110-5L-6L protein, demonstrating that deletion of the MGF110-5L-6L gene can enable DIVA capabilities in preexisting vaccine candidates. IMPORTANCE Currently, there are no African swine fever (ASF) commercial vaccines that can be used to prevent or control the spread of ASF. The only effective experimental vaccines against ASF are live-attenuated vaccines. However, these experimental vaccines, which rely on a deletion of a specific gene of the current circulating strain of ASF, make it hard to tell the difference between a vaccinated and an infected animal. In our search for a serological marker, we identified that the virus protein encoded by the MGF110-5L-6L gene induced an immune response, making a virus lacking this gene a vaccine candidate that allows the differentiation of infected from vaccinated animals (DIVA). Here, we show that deletion of MGF110-5L-6L does not affect virulence or virus replication. However, when the deletion of MGF110-5L-6L was added to vaccine candidate ASFV-G-ΔI177L, a reduction in the effectiveness of the vaccine occurred.
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The Development of a Multiplex Real-Time Quantitative PCR Assay for the Differential Detection of the Wild-Type Strain and the MGF505-2R, EP402R and I177L Gene-Deleted Strain of the African Swine Fever Virus. Animals (Basel) 2022; 12:ani12141754. [PMID: 35883301 PMCID: PMC9311895 DOI: 10.3390/ani12141754] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/04/2022] [Accepted: 07/05/2022] [Indexed: 11/17/2022] Open
Abstract
Simple Summary African swine fever (ASF) was first reported in August 2018 in China, and the naturally gene-deleted ASFV strain was first identified in 2020 in this country. The vaccine candidates that deleted some virulent genes from the virulent parental strains have also been reported in many countries. To differentiate the wild-type and gene-deleted ASFV strains, four pairs of specific primers and TaqMan probes targeting the ASFV B646L (p72), I177L, MGF505-2R and EP402R (CD2v) genes were designed. After optimizing the reaction conditions, a multiplex real-time qPCR assay for the differential detection of the wild-type and gene-deleted ASFV strains was developed. The assay was further used to test 4239 clinical samples, and 534 samples were positive for ASFV, of which 30 samples lacked B646L, I177L, MGF505-2R and/or EP402R genes. The assay showed high specificity, sensitivity and repeatability, and it provided a reliable method for evaluating ASFV in clinical samples. Abstract African swine fever virus (ASFV) causes African swine fever (ASF), a devastating hemorrhagic disease of domestic pigs and wild boars. Currently, the MGF505R, EP402R (CD2v) and I177L gene-deleted ASFV strains were confirmed to be the ideal vaccine candidate strains. To develop an assay for differentiating the wild-type and gene-deleted ASFV strains, four pairs of specific primers and TaqMan probes targeting the ASFV B646L (p72), I177L, MGF505-2R and EP402R (CD2v) genes were designed. A multiplex real-time qPCR assay for the differential detection of the wild-type and gene-deleted ASFV strains was developed after optimizing the reaction conditions, including the annealing temperature, primer concentration and probe concentration. The results showed that the multiplex real-time qPCR assay can specifically test the ASFV B646L (p72), I177L, MGF505-2R and EP402R (CD2v) genes with a limit of detection (LOD) of 32.1 copies/μL for the B646L (p72) gene, and 3.21 copies/μL for the I177L, MGF505-2R and EP402R (CD2v) genes. However, the assay cannot test for the classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine epidemic diarrhea virus (PEDV), porcine deltacoronavirus (PDCoV), porcine circovirus type 2 (PCV2), PCV3 and pseudorabies virus (PRV). The assay demonstrated good repeatability and reproducibility with coefficients of variation (CV) less than 1.56% for both the intra- and inter-assay. The assay was used to test 4239 clinical samples, and the results showed that 12.60% (534/4239) samples were positive for ASFV, of which 10 samples lacked the EP402R gene, 6 samples lacked the MGF505-2R gene and 14 samples lacked the EP402R and MGF505-2R genes. The results indicated that the multiplex real-time qPCR developed in this study can provide a rapid, sensitive and specific diagnostic tool for the differential detection of the ASFV B646L, I177L, MGF505-2R and EP402R genes.
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Deletion of the H108R Gene Reduces Virulence of the Pandemic Eurasia Strain of African Swine Fever Virus with Surviving Animals Being Protected against Virulent Challenge. J Virol 2022; 96:e0054522. [DOI: 10.1128/jvi.00545-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Currently, there is no commercial vaccine available to prevent ASF. ASFV-Georgia2007 (ASFV-G) and its field isolate derivatives are producing a large pandemic which is drastically affecting pork production in Eurasia.
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45
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Vuono EA, Ramirez-Medina E, Pruitt S, Rai A, Espinoza N, Silva E, Velazquez-Salinas L, Gladue DP, Borca MV. Deletion of the ASFV dUTPase Gene E165R from the Genome of Highly Virulent African Swine Fever Virus Georgia 2010 Does Not Affect Virus Replication or Virulence in Domestic Pigs. Viruses 2022; 14:v14071409. [PMID: 35891389 PMCID: PMC9320246 DOI: 10.3390/v14071409] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/21/2022] [Accepted: 06/24/2022] [Indexed: 02/05/2023] Open
Abstract
African swine fever (ASF) is a frequently lethal disease of domestic and wild swine currently producing a pandemic affecting pig production in Eurasia. The causative agent, ASF virus (ASFV) is a structurally complex virus with a large genome harboring over 150 genes. One of them, E165R, encodes for a protein belonging to the dUTPase family. The fine structure of the purified protein has been recently analyzed and its dUTPase activity tested. In addition, it has been reported that a BA71 mutant virus, adapted to growth in Vero cells, lacking the E165R gene presented a drastic decreased replication in swine macrophages, its natural target cell. Herein, we report the development of a recombinant virus, ASFV-G-∆E165R, harboring the deletion of the E165R gene from the genome of the highly virulent field isolate ASFV Georgia 2010 (ASFV-G). Interestingly, ASFV-G-∆E165R replicates in primary swine macrophage cultures as efficiently as the parental virus ASFV-G. In addition, ASFV-G-∆E165R also replicates in experimentally inoculated domestic pigs with equal efficacy as ASFV-G and produced a lethal disease almost indistinguishable from that induced by the parental virus. Therefore, results presented here clearly demonstrated that E165R gene is not essential or important for ASFV replication in swine macrophages nor disease production in domestic pigs.
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Affiliation(s)
- Elizabeth A. Vuono
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA; (E.A.V.); (E.R.-M.); (S.P.); (A.R.); (N.E.); (E.S.); (L.V.-S.)
- Department of Pathobiology and Population Medicine, Mississippi State University, Starkville, MS 39762, USA
| | - Elizabeth Ramirez-Medina
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA; (E.A.V.); (E.R.-M.); (S.P.); (A.R.); (N.E.); (E.S.); (L.V.-S.)
| | - Sarah Pruitt
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA; (E.A.V.); (E.R.-M.); (S.P.); (A.R.); (N.E.); (E.S.); (L.V.-S.)
| | - Ayushi Rai
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA; (E.A.V.); (E.R.-M.); (S.P.); (A.R.); (N.E.); (E.S.); (L.V.-S.)
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Nallely Espinoza
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA; (E.A.V.); (E.R.-M.); (S.P.); (A.R.); (N.E.); (E.S.); (L.V.-S.)
| | - Ediane Silva
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA; (E.A.V.); (E.R.-M.); (S.P.); (A.R.); (N.E.); (E.S.); (L.V.-S.)
| | - Lauro Velazquez-Salinas
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA; (E.A.V.); (E.R.-M.); (S.P.); (A.R.); (N.E.); (E.S.); (L.V.-S.)
| | - Douglas P. Gladue
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA; (E.A.V.); (E.R.-M.); (S.P.); (A.R.); (N.E.); (E.S.); (L.V.-S.)
- Correspondence: (D.P.G.); (M.V.B.)
| | - Manuel V. Borca
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Greenport, NY 11944, USA; (E.A.V.); (E.R.-M.); (S.P.); (A.R.); (N.E.); (E.S.); (L.V.-S.)
- Correspondence: (D.P.G.); (M.V.B.)
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Huang Z, Xu Z, Cao H, Zeng F, Wang H, Gong L, Zhang S, Cao S, Zhang G, Zheng Z. A Triplex PCR Method for Distinguishing the Wild-Type African Swine Fever Virus From the Deletion Strains by Detecting the Gene Insertion. Front Vet Sci 2022; 9:921907. [PMID: 35836498 PMCID: PMC9274085 DOI: 10.3389/fvets.2022.921907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 06/03/2022] [Indexed: 11/23/2022] Open
Abstract
To date, there is no effective vaccine or antiviral therapy available to prevent or treat African swine fever virus (ASFV) infections. ASFV gene deletion strains have been proposed as promising anti-ASFV vaccine candidates. In recent years, most ASFV gene deletion strains worldwide have been recombinant strains expressing EGFP or mCherry as markers. Therefore, in this study, a new triplex real-time PCR (RT-PCR) method was established for the broad and accurate differentiation of ASFV wild-type vs. gene deletion strains. We designed three pairs of primers and probes to target B646L, EGFP, and mCherry, and RT-PCR was used to detect these three genes simultaneously. The detection method prevented non-specific amplification of porcine reproductive and respiratory syndrome virus, porcine epidemic diarrhea virus, circovirus type 2, pseudorabies virus, and classical swine fever virus genes. The minimum copy number of standard plasmid DNA detected using triplex RT-PCR was 9.49, 15.60, and 9.60 copies for B646L, EGFP, and mCherry, respectively. Importantly, of the 1646 samples analyzed in this study, 67 were positive for ASFV, all corresponding to the wild-type virus. Overall, our data show that the triplex RT-PCR method established in this study can specifically identify both ASFV wild-type and gene deletion strains.
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Affiliation(s)
- Zhao Huang
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- African Swine Fever Regional Laboratory of China, Guangzhou, China
| | - Zhiying Xu
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- African Swine Fever Regional Laboratory of China, Guangzhou, China
| | - Haoxuan Cao
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- African Swine Fever Regional Laboratory of China, Guangzhou, China
| | - Fanliang Zeng
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- African Swine Fever Regional Laboratory of China, Guangzhou, China
| | - Heng Wang
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- African Swine Fever Regional Laboratory of China, Guangzhou, China
- Research Center for African Swine Fever Prevention and Control, South China Agricultural University, Guangzhou, China
| | - Lang Gong
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- African Swine Fever Regional Laboratory of China, Guangzhou, China
| | | | - Sen Cao
- Haifeng Animal Disease Prevention and Control Center, Shanwei, China
| | - Guihong Zhang
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Research Center for African Swine Fever Prevention and Control, South China Agricultural University, Guangzhou, China
- Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, China
- Key Laboratory of Animal Vaccine Development, Ministry of Agriculture and Rural Affairs, Guangzhou, China
- Guihong Zhang
| | - Zezhong Zheng
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China
- Research Center for African Swine Fever Prevention and Control, South China Agricultural University, Guangzhou, China
- *Correspondence: Zezhong Zheng
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47
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Canter JA, Aponte T, Ramirez-Medina E, Pruitt S, Gladue DP, Borca MV, Zhu JJ. Serum Neutralizing and Enhancing Effects on African Swine Fever Virus Infectivity in Adherent Pig PBMC. Viruses 2022; 14:v14061249. [PMID: 35746720 PMCID: PMC9229155 DOI: 10.3390/v14061249] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/03/2022] [Accepted: 06/07/2022] [Indexed: 12/28/2022] Open
Abstract
African swine fever virus (ASFV) causes hemorrhagic fever with mortality rates of up to 100% in domestic pigs. Currently, there are no commercial vaccines for the disease. Only some live-attenuated viruses have been able to protect pigs from ASFV infection. The immune mechanisms involved in the protection are unclear. Immune sera can neutralize ASFV but incompletely. The mechanisms involved are not fully understood. Currently, there is no standardized protocol for ASFV neutralization assays. In this study, a flow cytometry-based ASFV neutralization assay was developed and tested in pig adherent PBMC using a virulent ASFV containing a fluorescent protein gene as a substrate for neutralization. As with previous studies, the percentage of infected macrophages was approximately five time higher than that of infected monocytes, and nearly all infected cells displayed no staining with anti-CD16 antibodies. Sera from naïve pigs and pigs immunized with a live-attenuated ASFV and fully protected against parental virus were used in the assay. The sera displayed incomplete neutralization with MOI-dependent neutralizing efficacies. Extracellular, but not intracellular, virions suspended in naïve serum were more infectious than those in the culture medium, as reported for some enveloped viruses, suggesting a novel mechanism of ASFV infection in macrophages. Both the intracellular and extracellular virions could not be completely neutralized.
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Affiliation(s)
- Jessica A. Canter
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Orient, NY 11957, USA; (J.A.C.); (T.A.); (E.R.-M.); (S.P.)
- Plum Island Animal Disease Center, Oak Ridge Institute for Science and Education, Oak Ridge, TN 37830, USA
| | - Theresa Aponte
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Orient, NY 11957, USA; (J.A.C.); (T.A.); (E.R.-M.); (S.P.)
- Plum Island Animal Disease Center, Oak Ridge Institute for Science and Education, Oak Ridge, TN 37830, USA
| | - Elizabeth Ramirez-Medina
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Orient, NY 11957, USA; (J.A.C.); (T.A.); (E.R.-M.); (S.P.)
| | - Sarah Pruitt
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Orient, NY 11957, USA; (J.A.C.); (T.A.); (E.R.-M.); (S.P.)
| | - Douglas P. Gladue
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Orient, NY 11957, USA; (J.A.C.); (T.A.); (E.R.-M.); (S.P.)
- Correspondence: (D.P.G.); (M.V.B.); (J.J.Z.); Tel.: +1-631-323-3131 (D.P.G.); +1-631-323-3035 (M.V.B.); +1-631-323-3186 (J.J.Z.)
| | - Manuel V. Borca
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Orient, NY 11957, USA; (J.A.C.); (T.A.); (E.R.-M.); (S.P.)
- Correspondence: (D.P.G.); (M.V.B.); (J.J.Z.); Tel.: +1-631-323-3131 (D.P.G.); +1-631-323-3035 (M.V.B.); +1-631-323-3186 (J.J.Z.)
| | - James J. Zhu
- Foreign Animal Disease Research Unit, Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Orient, NY 11957, USA; (J.A.C.); (T.A.); (E.R.-M.); (S.P.)
- Correspondence: (D.P.G.); (M.V.B.); (J.J.Z.); Tel.: +1-631-323-3131 (D.P.G.); +1-631-323-3035 (M.V.B.); +1-631-323-3186 (J.J.Z.)
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48
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Ramirez-Medina E, Vuono EA, Pruitt S, Rai A, Espinoza N, Valladares A, Silva E, Velazquez-Salinas L, Borca MV, Gladue DP. Deletion of African Swine Fever Virus Histone-like Protein, A104R from the Georgia Isolate Drastically Reduces Virus Virulence in Domestic Pigs. Viruses 2022; 14:v14051112. [PMID: 35632853 PMCID: PMC9146580 DOI: 10.3390/v14051112] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/10/2022] [Accepted: 05/17/2022] [Indexed: 02/06/2023] Open
Abstract
African swine fever virus (ASFV) is the etiological agent of a frequently lethal disease, ASF, affecting domestic and wild swine. Currently, ASF is causing a pandemic affecting pig production in Eurasia. There are no vaccines available, and therefore control of the disease is based on culling infected animals. We report here that deletion of the ASFV gene A104R, a virus histone-like protein, from the genome of the highly virulent ASFV-Georgia2010 (ASFV-G) strain induces a clear decrease in virus virulence when experimentally inoculated in domestic swine. A recombinant virus lacking the A104R gene, ASFV-G-∆A104R, was developed to assess the role of the A104R gene in disease production in swine. Domestic pigs were intramuscularly inoculated with 102 HAD50 of ASFV-G-∆A104R, and compared with animals that received a similar dose of virulent ASFV-G. While all ASFV-G inoculated animals developed a fatal form of the disease, animals receiving ASFV-G-∆A104R survived the challenge, remaining healthy during the 28-day observational period, with the exception of only one showing a protracted but fatal form of the disease. ASFV-G-∆A104R surviving animals presented protracted viremias with reduced virus titers when compared with those found in animals inoculated with ASFV-G, and all of them developed a strong virus-specific antibody response. This is the first report demonstrating that the A104R gene is involved in ASFV virulence in domestic swine, suggesting that A104R deletion may be used to increase the safety profile of currently experimental vaccines.
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Affiliation(s)
- Elizabeth Ramirez-Medina
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA; (E.R.-M.); (E.A.V.); (S.P.); (A.R.); (N.E.); (A.V.); (E.S.); (L.V.-S.)
| | - Elizabeth A. Vuono
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA; (E.R.-M.); (E.A.V.); (S.P.); (A.R.); (N.E.); (A.V.); (E.S.); (L.V.-S.)
- Department of Pathobiology and Population Medicine, Mississippi State University, P.O. Box 6100, Starkville, MS 39762, USA
| | - Sarah Pruitt
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA; (E.R.-M.); (E.A.V.); (S.P.); (A.R.); (N.E.); (A.V.); (E.S.); (L.V.-S.)
| | - Ayushi Rai
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA; (E.R.-M.); (E.A.V.); (S.P.); (A.R.); (N.E.); (A.V.); (E.S.); (L.V.-S.)
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN 37830, USA
| | - Nallely Espinoza
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA; (E.R.-M.); (E.A.V.); (S.P.); (A.R.); (N.E.); (A.V.); (E.S.); (L.V.-S.)
| | - Alyssa Valladares
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA; (E.R.-M.); (E.A.V.); (S.P.); (A.R.); (N.E.); (A.V.); (E.S.); (L.V.-S.)
- College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
| | - Ediane Silva
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA; (E.R.-M.); (E.A.V.); (S.P.); (A.R.); (N.E.); (A.V.); (E.S.); (L.V.-S.)
| | - Lauro Velazquez-Salinas
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA; (E.R.-M.); (E.A.V.); (S.P.); (A.R.); (N.E.); (A.V.); (E.S.); (L.V.-S.)
| | - Manuel V. Borca
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA; (E.R.-M.); (E.A.V.); (S.P.); (A.R.); (N.E.); (A.V.); (E.S.); (L.V.-S.)
- Correspondence: (M.V.B.); (D.P.G.)
| | - Douglas P. Gladue
- Plum Island Animal Disease Center, Agricultural Research Service, United States Department of Agriculture Greenport, Greenport, NY 11944, USA; (E.R.-M.); (E.A.V.); (S.P.); (A.R.); (N.E.); (A.V.); (E.S.); (L.V.-S.)
- Correspondence: (M.V.B.); (D.P.G.)
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49
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Ramirez-Medina E, O’Donnell V, Silva E, Espinoza N, Velazquez-Salinas L, Moran K, Daite DA, Barrette R, Faburay B, Holland R, Gladue DP, Borca MV. Experimental Infection of Domestic Pigs with an African Swine Fever Virus Field Strain Isolated in 2021 from the Dominican Republic. Viruses 2022; 14:v14051090. [PMID: 35632831 PMCID: PMC9145207 DOI: 10.3390/v14051090] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 05/10/2022] [Accepted: 05/12/2022] [Indexed: 12/16/2022] Open
Abstract
African swine fever virus (ASFV) is the etiological agent of African swine fever (ASF), a disease of domestic and wild swine that has spread throughout a large geographical area including Central Europe, East and Southeast Asia, and Southern Africa. Typically, the clinical presentation of the disease in affected swine heavily depends on the virulence of the ASFV strain. Very recently, ASFV was detected in the Dominican Republic (DR) and Haiti, constituting the first diagnosis of ASFV in more than 40 years in the Western hemisphere. In this report, the clinical presentation of the disease in domestic pigs inoculated with an ASFV field strain isolated from samples collected in the DR (ASFV-DR21) was observed. Two groups of domestic pigs were inoculated either intramuscularly (IM) or oronasally (ON) with ASFV-DR21 (104 hemadsorbing dose-50% (HAD50)). A group of naïve pigs (designated as the contact group) was co-housed with the ASFV-DR21 IM-inoculated animals to evaluate ASFV transmission and disease manifestation. Animals inoculated IM with ASFV-DR21 developed an acute disease leading to humane euthanasia at approximately day 7 post-inoculation (pi). Interestingly, animals inoculated via the ON route with ASFV-DR21 developed a heterogeneous pattern of disease kinetics. One animal developed an acute form of the disease and was euthanized on day 7 pi, another animal experienced a protracted presentation of the disease with euthanasia by day 16 pi, and the remaining two animals presented a milder form of the disease, surviving through the 28-day observational period. The contact animals also presented with a heterogenous presentation of the disease. Three of the animals presented protracted but severe forms of the disease being euthanized at days 14, 15 and 21 pi. The other two animals presented with a milder form of the disease, surviving the entire observational period. In general, virus titers in the blood of animals in all study groups closely followed the clinical presentation of the disease, both in length and extent. Importantly, all animals presenting with a prolonged form of the disease, as well as those surviving throughout the observational period, developed a strong ASFV-specific antibody response. These results suggest that ASFV-DR21, unless inoculated parenterally, produces a spectrum of clinical disease, with some animals experiencing an acute fatal form while others presented with a mild transient disease accompanied by the induction of a strong antibody response. At the time of publication, this is the first report characterizing the virulent phenotype of an ASFV field strain isolated from samples collected in the DR during the 2021 outbreak and provides information that may be used in developing epidemiological management measures to control ASF on the island of Hispaniola.
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Affiliation(s)
- Elizabeth Ramirez-Medina
- Plum Island Animal Disease Center, Agricultural Research Service, USDA, Greenport, NY 11944, USA; (E.R.-M.); (E.S.); (N.E.); (L.V.-S.)
| | - Vivian O’Donnell
- Plum Island Animal Disease Center, Animal and Plant Health Inspection Service, USDA, Greenport, NY 11944, USA; (V.O.); (K.M.); (D.A.D.); (R.B.); (B.F.); (R.H.)
| | - Ediane Silva
- Plum Island Animal Disease Center, Agricultural Research Service, USDA, Greenport, NY 11944, USA; (E.R.-M.); (E.S.); (N.E.); (L.V.-S.)
| | - Nallely Espinoza
- Plum Island Animal Disease Center, Agricultural Research Service, USDA, Greenport, NY 11944, USA; (E.R.-M.); (E.S.); (N.E.); (L.V.-S.)
| | - Lauro Velazquez-Salinas
- Plum Island Animal Disease Center, Agricultural Research Service, USDA, Greenport, NY 11944, USA; (E.R.-M.); (E.S.); (N.E.); (L.V.-S.)
| | - Karen Moran
- Plum Island Animal Disease Center, Animal and Plant Health Inspection Service, USDA, Greenport, NY 11944, USA; (V.O.); (K.M.); (D.A.D.); (R.B.); (B.F.); (R.H.)
| | - Dee Ann Daite
- Plum Island Animal Disease Center, Animal and Plant Health Inspection Service, USDA, Greenport, NY 11944, USA; (V.O.); (K.M.); (D.A.D.); (R.B.); (B.F.); (R.H.)
| | - Roger Barrette
- Plum Island Animal Disease Center, Animal and Plant Health Inspection Service, USDA, Greenport, NY 11944, USA; (V.O.); (K.M.); (D.A.D.); (R.B.); (B.F.); (R.H.)
| | - Bonto Faburay
- Plum Island Animal Disease Center, Animal and Plant Health Inspection Service, USDA, Greenport, NY 11944, USA; (V.O.); (K.M.); (D.A.D.); (R.B.); (B.F.); (R.H.)
| | - Robin Holland
- Plum Island Animal Disease Center, Animal and Plant Health Inspection Service, USDA, Greenport, NY 11944, USA; (V.O.); (K.M.); (D.A.D.); (R.B.); (B.F.); (R.H.)
| | - Douglas P. Gladue
- Plum Island Animal Disease Center, Agricultural Research Service, USDA, Greenport, NY 11944, USA; (E.R.-M.); (E.S.); (N.E.); (L.V.-S.)
- Correspondence: (D.P.G.); (M.V.B.)
| | - Manuel V. Borca
- Plum Island Animal Disease Center, Agricultural Research Service, USDA, Greenport, NY 11944, USA; (E.R.-M.); (E.S.); (N.E.); (L.V.-S.)
- Correspondence: (D.P.G.); (M.V.B.)
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50
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Tran XH, Phuong LTT, Huy NQ, Thuy DT, Nguyen VD, Quang PH, Ngôn QV, Rai A, Gay CG, Gladue DP, Borca MV. Evaluation of the Safety Profile of the ASFV Vaccine Candidate ASFV-G-ΔI177L. Viruses 2022; 14:v14050896. [PMID: 35632638 PMCID: PMC9147362 DOI: 10.3390/v14050896] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 04/20/2022] [Accepted: 04/20/2022] [Indexed: 01/09/2023] Open
Abstract
African swine fever (ASF) is the cause of a recent pandemic that is posing a threat to much of the world swine production. The etiological agent, ASF virus (ASFV), infects domestic and wild swine, producing a variety of clinical presentations depending on the virus strain and the genetic background of the pigs infected. No commercial vaccine is currently available, although recombinant live attenuated vaccine candidates have been shown to be efficacious. In addition to determining efficacy, it is paramount to evaluate the safety profile of a live attenuated vaccine. The presence of residual virulence and the possibility of reversion to virulence are two of the concerns that must be evaluated in the development of live attenuated vaccines. Here we evaluate the safety profile of an efficacious live attenuated vaccine candidate, ASFV-G-ΔI177L. Results from safety studies showed that ASFV-G-ΔI177L remains genetically stable and phenotypically attenuated during a five-passage reversion to virulence study in domestic swine. In addition, large-scale experiments to detect virus shedding and transmission confirmed that even under varying conditions, ASFV-G-ΔI177L is a safe live attenuated vaccine.
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Affiliation(s)
- Xuan Hanh Tran
- National Veterinary Joint Stock Company (NAVETCO), Ho Chi Minh City 70000, Vietnam; (L.T.T.P.); (N.Q.H.); (D.T.T.); (N.V.D.); (P.H.Q.); (Q.V.N.)
- Correspondence: (X.H.T.); (D.P.G.); (M.V.B.)
| | - Le Thi Thu Phuong
- National Veterinary Joint Stock Company (NAVETCO), Ho Chi Minh City 70000, Vietnam; (L.T.T.P.); (N.Q.H.); (D.T.T.); (N.V.D.); (P.H.Q.); (Q.V.N.)
| | - Nguyen Quang Huy
- National Veterinary Joint Stock Company (NAVETCO), Ho Chi Minh City 70000, Vietnam; (L.T.T.P.); (N.Q.H.); (D.T.T.); (N.V.D.); (P.H.Q.); (Q.V.N.)
| | - Do Thanh Thuy
- National Veterinary Joint Stock Company (NAVETCO), Ho Chi Minh City 70000, Vietnam; (L.T.T.P.); (N.Q.H.); (D.T.T.); (N.V.D.); (P.H.Q.); (Q.V.N.)
| | - Van Dung Nguyen
- National Veterinary Joint Stock Company (NAVETCO), Ho Chi Minh City 70000, Vietnam; (L.T.T.P.); (N.Q.H.); (D.T.T.); (N.V.D.); (P.H.Q.); (Q.V.N.)
| | - Pham Hào Quang
- National Veterinary Joint Stock Company (NAVETCO), Ho Chi Minh City 70000, Vietnam; (L.T.T.P.); (N.Q.H.); (D.T.T.); (N.V.D.); (P.H.Q.); (Q.V.N.)
| | - Quách Võ Ngôn
- National Veterinary Joint Stock Company (NAVETCO), Ho Chi Minh City 70000, Vietnam; (L.T.T.P.); (N.Q.H.); (D.T.T.); (N.V.D.); (P.H.Q.); (Q.V.N.)
| | - Ayushi Rai
- Plum Island Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Greenport, NY 11944, USA;
| | - Cyril G. Gay
- Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705, USA;
| | - Douglas Paul Gladue
- Plum Island Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Greenport, NY 11944, USA;
- Correspondence: (X.H.T.); (D.P.G.); (M.V.B.)
| | - Manuel Victor Borca
- Plum Island Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Greenport, NY 11944, USA;
- Correspondence: (X.H.T.); (D.P.G.); (M.V.B.)
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