Li Chengjun, Ping Jihui, Jing Bo, Deng Guohua, Jiang Yongping, Li Yanbing, Tian Guobin, Yu Kangzhen, Bu Zhigao, Chen Hualan
Harbin Veterinary Research Institute, CAAS, 427 Maduan Street, Harbin, Heilongjiang 150001, People's Republic of China.
Biochem Biophys Res Commun. 2008 Jul 25;372(2):293-7. doi: 10.1016/j.bbrc.2008.05.057. Epub 2008 May 22.
Using plasmid-based reverse genetics, we generated a molecularly altered virus, H5N1/PR8-5B19, containing modified HA and NA genes from A/Goose/Guangdong/1/96 (GS/GD/1/96). In the H5N1/PR8-5B19 virus, the HA cleavage site was modified to resemble that of low-pathogenic avian strains and a portion of the NA stalk region was replaced by the immunodominant 5B19 epitope of the S2 glycoprotein of murine hepatitis virus (MHV). H5N1/PR8-5B19 is not lethal to embryonated eggs or chickens. Chickens immunized with the H5N1/PR8-5B19 inactivated vaccine produced high levels of HI antibody and a measurable antibody response against the MHV 5B19 epitope, and were fully protected against subsequent challenge with different highly pathogenic H5N1 avian influenza viruses. H5N1/PR8-5B19 is therefore an attractive marker vaccine candidate, eliciting a strong, protective antibody response and enabling serological discrimination between vaccinated and wild-type virus-infected chickens.
利用基于质粒的反向遗传学技术，我们构建了一种分子改造病毒，即H5N1/PR8 - 5B19，它含有来自A/Goose/Guangdong/1/96（GS/GD/1/96）的修饰过的血凝素（HA）和神经氨酸酶（NA）基因。在H5N1/PR8 - 5B19病毒中，HA裂解位点被改造得类似于低致病性禽流感毒株的裂解位点，并且NA茎区的一部分被鼠肝炎病毒（MHV）S2糖蛋白的免疫显性5B19表位所取代。H5N1/PR8 - 5B19对鸡胚或鸡不具有致死性。用H5N1/PR8 - 5B19灭活疫苗免疫的鸡产生了高水平的血凝抑制（HI）抗体以及针对MHV 5B19表位的可检测抗体反应，并且对随后不同高致病性H5N1禽流感病毒的攻击具有完全的保护作用。因此，H5N1/PR8 - 5B19是一种有吸引力的标记疫苗候选物，能引发强烈的保护性抗体反应，并能够在接种疫苗的鸡和野生型病毒感染的鸡之间进行血清学区分。
