重组禽流感病毒二价灭活疫苗对H5N1亚型7.2分支病毒的攻毒保护性研究  

Protection efficacy of avian influenza ressortant virus bivalent inactivated vaccines against the H5N1 clade 7.2 virus

作　　者：曾显营[1] 刘丽玲[1] 张盼涛[1] 杨婧[1] 刘景利[2] 徐佳[2] 田国彬[1] 陈化兰[1] 

机构地区：[1]中国农业科学院哈尔滨兽医研究所、兽医生物技术国家重点实验室/农业部动物流感重点开放实验室,黑龙江哈尔滨150001 [2]哈尔滨维科生物技术开发公司,黑龙江哈尔滨150069

出　　处：《中国预防兽医学报》2012年第12期988-992,共5页Chinese Journal of Preventive Veterinary Medicine

基　　金：现代农业产业技术体系建设专项资金(CARS-42-G08);黑龙江省杰出青年科学基金(JC201119)

摘　　要：为有效防控2006年以来出现的H5亚型7.2分支禽流感病毒(AIV)引起的免疫鸡群高致病性禽流感(HPAI)的流行,我们构建了重组AIV Re-4疫苗株,研制出含有重组AIV Re-4株的H5亚型二价系列灭活疫苗,并在我国北方地区使用,有效地控制了其流行。2012年我国北方地区再次出现7.2分支病毒引起的HPAI疫情。为评估现有H5亚型二价系列灭活疫苗对该分支病毒的免疫保护效力,本研究首先通过SPF鸡进行免疫攻毒试验评估。结果表明,分别以每羽份(0.3 mL/只)的Re-5+Re-4株和Re-6+Re-4株重组AIV H5二价油乳剂灭活疫苗免疫SPF鸡,免疫3周后针对重组AIV Re-4株的HI抗体均达到8 log2以上;经鼻腔接种7.2分支AIV CK/NX/2/12株(100 LD50)攻毒后,免疫鸡均获得完全保护,即无任何临床症状和排毒现象,而对照组SPF鸡全部发病死亡。此外,以哈尔滨当地养殖场中免疫H5亚型AIV灭活疫苗的48只商品蛋鸡进行攻毒试验,结果显示,商品蛋鸡血清中针对重组AIV Re-4株HI抗体平均滴度为8.3 log2,采用相同方式攻毒后也获得完全保护。本研究结果表明,Re-5+Re-4株和Re-6+Re-4株重组AIV H5二价灭活疫苗均能够对H5亚型7.2分支病毒的攻击提供良好的免疫保护效果。The clade 7.2 H5N1 subtype avian influenza virus （A1V） emerged in 2006 and caused the outbreaks in vaccinated chicken flocks. We then developed a H5 subtype reassortant AIV of Re-4 vaccine strain as a critical portion of A1V combination inactivated vaccine, which had efficiently controlled the prevalence of clade 7.2 virus in North of China. However, the clade 7.2 virus re-emerged in 2012. It is necessary to evaluate the H5 bivalent inactivated vaccines of Re-5＋Re-4 and Re-6＋Re-4 against the clade 7.2 virus. In the present study, two groups of SPF chickens were vaccinated with 1 dose of either Re-5＋Re-4 or Re-6＋Re-4 inactivated vaccine and challenged intranasally with 100 LD50 of clade 7.2 virus （CK/NX/2/12） at 3-weeks post immunization. The results showed that the mean HI antibody titers to the antigen of Re-4 strain were all above 8log2 before challenge and all vaccinated birds survived without virus shedding and clinical signs during the two weeks observation period. On the contrary, all the birds in the control group died within 5 days post challenge. Furthermore, a total of 48 commercial layers vaccinated with the Re-5＋Re-4 bivalent inactivated vaccine were collected fi＇om chicken farms in Harbin for challenging test. The results showed that the mean HI antibody titers to Re-4 were 8.31og2, and all the birds were completely protected when challenged with the same dose of CK/NX/2/12. Our data indicated that both the H5 bivalent inactivated vaccines of Re-5＋Re-4 and Re-6＋Re-4 were able to provide effective protection in chickens against the clade 7,2 virus current prevalence in Northern China.

关 键 词：禽流感 二价灭活疫苗 H5亚型 7 2分支 免疫保护 

分 类 号：S852.65[农业科学—基础兽医学]