表达H5N1亚型高致病性禽流感病毒HA基因的DNA疫苗可保护SPF鸡抵抗同型病毒的致死性攻击

The DNA Vaccine Encoding Hemagglutinin Protect SPF Chicken Against Lethal H5N1 Avian Influenza Virus Challenge

将高致病力禽流感病毒分离株Ａ／Ｇｏｏｓｅ／Ｇｕａｎｇｄｏｎｇ／１／９６（ＨＳＮ１）（ＧＤ／１／９６）的ＨＡ基因ｃＤＮＡ片段克隆于强启动子ＣＭＶ下游，构建了 ＤＮＡ疫苗质粒 ｐＣＩＨ５，对其免疫保护性进行了三批不同层次的动物保护试验。试验Ｉ分为两部分，第一部分为ｐＣＩＨ５一次免疫组（１０μｇ、４０μｇ、７０μｇ、１００μｇ、１５０μｇ）、油苗组及空白对照组，第二部分为 ｐＣＩＨ５两次免疫组（５μｇ、２０μｇ、３５μｇ、５０μｇ）及其对照组，ｐＣＩＨ５以２００μｌ腿肌两点注射，一次免疫组于免疫后３周以１０ＬＤ５０ＣＤ／１／９６攻毒，两次免疫组首免后３周加强免疫一次，二免后２周以５０ＬＤ５０ＣＤ／１／９６攻毒，免疫及攻毒前后均采血检测ＨＩ抗体和ＡＧＰ抗体，攻毒后７天采集泻殖腔棉拭子分离病毒。试验Ⅱ分为５０μｇ和 １００μｇ（１００μｌ）两次免疫组及对照组，攻毒剂量为 １０ＬＤ５０ＣＤ／１／９６。试验Ⅲ为试验Ⅱ的重复试验，但免疫注射体积为２００μｌ。结果，三批试验的所有对照鸡在攻毒后 ２－ ８天全部死亡；试验Ⅰ中 １０μｇ、４０μｇ、７０μｇ、１００μｇ和 １５０μｇ ｐＣＩＨ５一次免疫，但免疫保护率分别为１２．５％（１／８?

The HA cDNA from HPAIV A/Goose /Guangdong/1/96 (H5 N1 ) (CD/1/96) was cloned under a CMV promoter to generate vac- cine plasmid pCIH5 .The protective experiments in SPF chickens were separated into three portions. The experiment I include inactived oil-emulsion vaccine groups(vaccine once),groups(vaccine twice)and two control groups.The one- time -vaccine groups were challenged with 10 LD50 GD/1/96 3 weeks after vaccine.The two-time-vaccine groups were boosted 3 weeks after prim- ing and were ch...