Xinheng Zhang1, Boliang Wu1, Yuanjia Liu2, Weiguo Chen3, Zhenkai Dai4, Yingzuo Bi1, Qingmei Xie5. 1. College of Animal Science, South China Agricultural University, Guangzhou 510642, PR China; Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, PR China. 2. Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, PR China; Key Laboratory of Animal Health Aquaculture and Environmental Control, Guangzhou 510642, PR China. 3. College of Animal Science, South China Agricultural University, Guangzhou 510642, PR China; Key Laboratory of Animal Health Aquaculture and Environmental Control, Guangzhou 510642, PR China; South China Collaborative Innovation Center for Poultry Disease Control and Product Safety, Guangzhou 510640, PR China. 4. College of Animal Science, South China Agricultural University, Guangzhou 510642, PR China; South China Collaborative Innovation Center for Poultry Disease Control and Product Safety, Guangzhou 510640, PR China. 5. College of Animal Science, South China Agricultural University, Guangzhou 510642, PR China; Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou 510642, PR China; Key Laboratory of Animal Health Aquaculture and Environmental Control, Guangzhou 510642, PR China; South China Collaborative Innovation Center for Poultry Disease Control and Product Safety, Guangzhou 510640, PR China. Electronic address: qmx@scau.edu.cn.
Abstract
BACKGROUND: Chicken anemia virus (CAV) is an immunosuppressive virus that causes chicken infectious anemia (CIA) which is a highly contagious avian disease. CAV causes major economic losses in the poultry industry worldwide. The current CAV vaccine is a live attenuated strain administered in the drinking water that risks horizontal infection of other chickens. The purpose of this study was to develop a novel vaccine against CAV that can be administered safely using a highly pathogenic isolate inactivated with β-propiolactone hydrolysis that would protect chicks from CAV. METHODS: Hens were vaccinated twice intramuscularly with a novel CAV GD-G-12 inactivated vaccine and the humoral immune responses of the hens and offspring were monitored by ELISA. A heterologous intramuscular challenge using the CAV strain GD-E-12 was conducted in the chicks hatched from vaccinated or unvaccinated hens. RESULTS: The vaccine strain, GD-G-12, was shown to be highly pathogenic prior to inactivation evidenced by thymic atrophy and bleeding, and weight loss. The inactivated vaccine was considered safe and showed no signs of pathogenicity. High titers of CAV specific antibodies were detected in the vaccinated hens and in their chicks, indicating vertical transfer of maternal antibodies. Furthermore, the chicks hatched from vaccinated hens were resistant to a heterologous CAV challenge and showed no signs of weight loss and thymic atrophy and bleeding. CONCLUSION: Our studies are proof of principle that inactivated GD-G-12 might be a novel vaccine candidate to prevent CAV infection, and highlight the utility of using an inactivated virus for this vaccine.
BACKGROUND:Chicken anemia virus (CAV) is an immunosuppressive virus that causes chickeninfectious anemia (CIA) which is a highly contagious avian disease. CAV causes major economic losses in the poultry industry worldwide. The current CAV vaccine is a live attenuated strain administered in the drinking water that risks horizontal infection of other chickens. The purpose of this study was to develop a novel vaccine against CAV that can be administered safely using a highly pathogenic isolate inactivated with β-propiolactone hydrolysis that would protect chicks from CAV. METHODS:Hens were vaccinated twice intramuscularly with a novel CAVGD-G-12 inactivated vaccine and the humoral immune responses of the hens and offspring were monitored by ELISA. A heterologous intramuscular challenge using the CAV strainGD-E-12 was conducted in the chicks hatched from vaccinated or unvaccinated hens. RESULTS: The vaccine strain, GD-G-12, was shown to be highly pathogenic prior to inactivation evidenced by thymic atrophy and bleeding, and weight loss. The inactivated vaccine was considered safe and showed no signs of pathogenicity. High titers of CAV specific antibodies were detected in the vaccinated hens and in their chicks, indicating vertical transfer of maternal antibodies. Furthermore, the chicks hatched from vaccinated hens were resistant to a heterologous CAV challenge and showed no signs of weight loss and thymic atrophy and bleeding. CONCLUSION: Our studies are proof of principle that inactivated GD-G-12 might be a novel vaccine candidate to prevent CAV infection, and highlight the utility of using an inactivated virus for this vaccine.
Authors: Abiodun Joseph Fatoba; Victoria T Adeleke; Leah Maharaj; Moses Okpeku; Adebayo A Adeniyi; Matthew A Adeleke Journal: Viruses Date: 2022-06-30 Impact factor: 5.818