Abstract:
Newcastle disease (ND) is a significant infectious disease in poultry, causing substantial economic losses in developing countries. To control ND, chickens must be vaccinated multiple times a year. In order to develop an improved vaccine that provides long-term protection, the F gene from genotype VII NDV was inserted into the herpesvirus of turkey (HVT) vaccine virus using CRISPR/Cas9-mediated NHEJ repair and Cre/LoxP technology. The immunogenicity and protective efficacy of the resulting recombinant vaccines were evaluated through antibody assays and virus challenge experiments. Two recombinant vaccines, rHVT-005/006-F and rHVT-US2-F, were generated, both exhibiting growth rates comparable with those of HVT in vitro and consistently expressing the F protein. One-day-old specific pathogen-free (SPF) chickens immunized with 2000 PFU/bird of either rHVT-005/006-F or rHVT-US2-F developed robust humoral immunity and were completely protected against challenge with the NDV F48E8 strain at 4 weeks post-vaccination (wpv). Furthermore, a single dose of these vaccines provided sustained protection for at least 52 wpv. Our study identifies rHVT-005/006-F and rHVT-US2-F as promising ND vaccine candidates, offering long-term protection with a single administration. Moreover, HVT-005/006 demonstrates promise for accommodating additional foreign genes, facilitating the construction of multiplex vaccines.
摘要:
新城疫(ND)是一种重要的禽类传染病,给发展中国家造成了巨大的经济损失。要控制ND,鸡必须每年接种多次疫苗。为了开发一种提供长期保护的改进疫苗,使用CRISPR/Cas9介导的NHEJ修复和Cre/LoxP技术,将基因型VIINDV的F基因插入火鸡疱疹病毒(HVT)疫苗病毒中.通过抗体测定和病毒攻击实验评价所得重组疫苗的免疫原性和保护效力。两种重组疫苗,rHVT-005/006-F和rHVT-US2-F,产生了,两者都表现出与体外HVT相当的生长速率,并且一致表达F蛋白。用rHVT-005/006-F或rHVT-US2-F的2000PFU/鸟免疫的一天大的无特定病原体(SPF)鸡产生了强大的体液免疫,并完全免受NDVF48E8菌株的攻击在疫苗接种后4周(wpv)。此外,单剂量的这些疫苗提供了至少52wpv的持续保护。我们的研究确定rHVT-005/006-F和rHVT-US2-F为有希望的ND疫苗候选物,通过单一管理提供长期保护。此外,HVT-005/006展示了容纳额外外源基因的前景,促进多重疫苗的构建。