Zhang Xinheng, Wu Boliang, Liu Yuanjia, Chen Weiguo, Dai Zhenkai, Bi Yingzuo, Xie Qingmei
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 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.
Vaccine. 2015 Apr 15;33(16):1916-22. doi: 10.1016/j.vaccine.2015.02.066. Epub 2015 Mar 8.
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.
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.
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.
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.
鸡贫血病毒（CAV）是一种免疫抑制性病毒，可引起鸡传染性贫血（CIA），这是一种高度传染性的禽类疾病。CAV在全球家禽业中造成重大经济损失。目前的CAV疫苗是一种通过饮水给药的减毒活毒株，存在水平感染其他鸡的风险。本研究的目的是开发一种针对CAV的新型疫苗，该疫苗可使用经β-丙内酯水解灭活的高致病性分离株安全给药，从而保护雏鸡免受CAV感染。
母鸡肌肉注射新型CAV GD-G-12灭活疫苗两次，通过ELISA监测母鸡及其后代的体液免疫反应。对接种或未接种疫苗的母鸡所孵出的雏鸡进行使用CAV毒株GD-E-!2的异源肌肉注射攻毒。
疫苗毒株GD-G-12在灭活前表现出高致病性，表现为胸腺萎缩、出血和体重减轻。灭活疫苗被认为是安全的，未表现出致病性迹象。在接种疫苗的母鸡及其雏鸡中检测到高滴度的CAV特异性抗体，表明母源抗体的垂直传递。此外，接种疫苗的母鸡所孵出的雏鸡对异源CAV攻毒具有抗性，未表现出体重减轻、胸腺萎缩和出血的迹象。
我们的研究证明，灭活的GD-G-12可能是预防CAV感染的新型候选疫苗，并突出了使用灭活病毒制备该疫苗的实用性。
