A Cell-Adapted Live-Attenuated Vaccine Candidate Protects Pigs against the Homologous Strain VNUA-ASFV-05L1, a Representative Strain of the Contemporary Pandemic African Swine Fever Virus
Author:
Truong Quang Lam1, Wang Lihua2ORCID, Nguyen Tuan Anh1, Nguyen Hoa Thi1, Tran Son Danh1, Vu Anh Thi1, Le Anh Dao1, Nguyen Van Giap3ORCID, Hoang Phuong Thi1, Nguyen Yen Thi1, Le Thi Luyen1, Van Thang Nguyen1, Huynh Thi My Le3, Lai Huong Thi Lan1ORCID, Madera Rachel2, Li Yuzhen2, Shi Jishu2ORCID, Nguyen Lan Thi1
Affiliation:
1. Key Laboratory of Veterinary Biotechnology, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Gia Lam, Ha Noi 12406, Vietnam 2. Center on Vaccine Evaluation and Alternatives for Antimicrobials, Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA 3. Department of Veterinary Microbiology and Infectious Diseases, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Gia Lam, Ha Noi 12406, Vietnam
Abstract
African swine fever (ASF) is a lethal and highly contagious transboundary animal disease with the potential for rapid international spread. Currently, there is no ASF vaccine commercially available. All infected animals must be isolated and culled immediately upon the confirmation of the presence of the virus. Studies leading to the rational development of protective ASF vaccines are urgently needed. Here, we generated a safe and efficacious live-attenuated vaccine (LAV) VNUA-ASFV-LAVL2 by serially passaging a field isolate (VNUA-ASFV-05L1, genotype II) in porcine alveolar macrophages (PAMs, 65 passages) and an immortalized porcine alveolar macrophage cell line (3D4/21, 55 passages). VNUA-ASFV-LAVL2 can efficiently replicate in both PAMs and 3D4/21 cells. It provides 100% protection, even with the low dose of 102 HAD50, to the vaccinated pigs against the challenge of contemporary pandemic ASFV field isolate. Pigs vaccinated with this LAV in a dose range of 102 to 105 HAD50 remained clinically healthy during both the 28-day observation period of immunization and the 28-day observation period of challenge. VNUA-ASFV-LAVL2 was eliminated from blood by 28 days post-inoculation (DPI), and from feces or oral fluids by 17 DPI. Although the vaccine strain in serum remained a safe and attenuated phenotype after five passages in swine, a reversion-to-virulence study using blood or tissue homogenates at peak viremia will be conducted in the future. ASFV-specific IgG antibodies and significant cellular immunity were detected in vaccinated pigs before the ASFV challenge. These results indicate that the VNUA-ASFV-LAVL2 strain is a safe and efficacious LAV against the genotype II ASFV strain responsible for current ASF outbreaks in Asia.
Funder
Vietnam Ministry of Science and Technology National Bio and Agro-Defense Facility Transition Fund, the USDA National Institute of Food and Agriculture, Hatch-Multistate project USDA ARS Non-Assistance Cooperative Agreements USDA NIFA Award USDA NIFA Subaward National Pork Board Grant Department of Homeland Security
Subject
Virology,Infectious Diseases
Reference39 articles.
1. African swine fever epidemiology and control;Dixon;Annu. Rev. Anim. Biosci.,2020 2. Karger, A., Pérez-Núñez, D., Urquiza, J., Hinojar, P., Alonso, C., Freitas, F.B., Revilla, Y., Le Potier, M.F., and Montoya, M. (2019). An Update on African Swine Fever Virology. Viruses, 11. 3. Genetic characterization of African swine fever virus isolates from soft ticks at the wildlife/domestic interface in Mozambique and identification of a novel genotype;Quembo;Transbound. Emerg. Dis.,2018 4. African swine fever (ASF): Five years around Europe;Mur;Vet. Microbiol.,2013 5. Molecular characterization of African swine fever virus, China, 2018;Ge;Emerg. Infect. Dis.,2018
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