H7亚型禽流感病毒血凝素基因重组鸡痘病毒活载体疫苗免疫原性评估  

Evaluation of the vaccine efficacy of a recombinant fowlpox virus expressing the hemagglutinin gene of H7 subtype avian influenza virus

作　　者：马文军[1] 陈化兰[1] 于康震[1] 张建林[1] 田国彬[1] 唐秀英[1] 

机构地区：[1]中国农业科学院哈尔滨兽医研究所农业部动物流感重点开放实验室

出　　处：《中国预防兽医学报》2004年第1期7-9,共3页Chinese Journal of Preventive Veterinary Medicine

基　　金：国家973项目(G1999011905)资助~~

摘　　要：本研究以细胞感染＿转染技术构建了一株表达H7亚型禽流感病毒(AIV)血凝素(HA)基因的重组鸡痘病毒rFPV＿HA。以5×105PFU的rFPV＿HA经翅下刺种免疫8周龄SPF鸡,免疫后第3周用100CID50的HA基因同源AIVA/ArfiStar/Eng＿Q/983/79(H7N1)进行人工感染,1周后采集泄殖腔棉拭子进行病毒分离。免疫后第三周及攻毒后第1、2周对所有动物进行静脉采血,检测血凝抑制(HI)抗体和免疫沉淀(AGP)抗体。结果,攻毒前部分rFPV＿HA免疫鸡可检测到HI抗体,但检测不到AGP抗体,野生型病毒(F017)接种组和空白对照组HI抗体和AGP抗体均为阴性。攻毒后rFPV＿HA免疫组的HI抗体上升速度明显高于野生型病毒接种组和空白对照组。rFPV＿HA免疫组有6/8的鸡为流感病毒分离阴性,野生型病毒接种组和空白对照组的试验鸡病毒分离全部为阳性。结果表明rFPV＿HA可诱导鸡产生有效的免疫保护反应,阻止或降低消化道病毒排泄。rFPV＿HA的成功构建为研制开发H7亚型禽流感活载体疫苗奠定了良好的基础。A recombinant fowlpox virus, rPFV-H7HA, has been generated to express an HA gene of a low pathogenic H7 subtype avian influenza virus. Two groups of SPF chickens were inoculated with 5×10~5 PFU recombinant virus and the parent fowlpox virus, respectively, through the wing puncture. The third group was left as unvaccinated control. Chickens were challenged with 100XCID50 of the HA gene donor virus three weeks after vaccination. Sera were collected the day before challenge, and 1 week and 2 weeks after challenge, respectively. Cloaca swabs were collected one week after challenge for virus shedding detection. Results showed that only 25 % chickens in the recombinant virus vaccinated group produced detectable HI antibody before challenge, and one week after challenge, the HI antibody titers of the recombinant virus vaccinated group increased very quickly. HI antibody was not detected from any chickens in the other two groups before challenge, but low titers were detected one week after challenge, and the titers increased to about 500 2 weeks after vaccination. Virus shedding was detected from 25 % chickens in the recombinant virus vaccinated group and 100 % chickens of the other two groups. Antibodies against the AIV nucleoprotein were positive in all of the chickens after challenge. These results indicated that the recombinant fowlpox virus vaccine could induce detectable HI antibody. rPFV-H7HA cannot totally prevent the replication of the challenged virus, but it coul1d partially prevent virus shedding through the cloaca.

关 键 词：禽流感病毒 H7亚型 血凝素基因 重组鸡痘病毒 疫苗 免疫原性评估 免疫保护反应 

分 类 号：S852.659.5[农业科学—基础兽医学] Q784[农业科学—兽医学]