免疫刺激复合物(ISCOM)介导的传染性法氏囊病病毒多聚蛋白基因免疫的研究  

Study on Immunogenicity of Plasmid DNA Encoding Polyprotein(VP2/VP4/VP3) of Infectious Bursal Disease Virus Formulated with ISCOM

作　　者：李建荣[1] 于涟[1] 黄耀伟[1] 梁雪芽[1] 孟松树[1] 谢荣辉[1] 

机构地区：[1]浙江大学动物预防医学研究所,浙江杭州310029

出　　处：《病毒学报》2001年第4期341-348,共8页Chinese Journal of Virology

基　　金：国家"8 6 3"高科技计划资助 ( 101-j99-0 2 )

摘　　要：将传染性法氏囊病病毒 (IBDV)ZJ2 0 0 0株的多聚蛋白 (VP2 /VP4/VP3)基因插入 pCI质粒的CMV启动子下游 ,构建了真核表达质粒pCI VP2 /VP4/VP3,在Lipofectin介导下转染Vero细胞进行了多聚蛋白的瞬时表达。以免疫刺激复合物 (ISCOM)为佐剂制备DNA疫苗 ,进行不同免疫剂量间、不同免疫途径间、一次免疫和二次免疫间的效果对比试验。结果表明 :以肌内和皮内联合免疫法效果最好 ,而口服和点眼等途径未能诱导足够的免疫反应 ;大于 2 0 0 μg的剂量DNA疫苗才能产生良好的免疫力 ;二次免疫的效果明显优于一次免疫。与常规的弱毒疫苗B87和D78相比 ,DNA疫苗产生中和抗体的潜伏期长、效价相对较低 ,对强毒攻击的保护率相当。本试验还证实 ,免疫刺激复合物具有明显提高DNA疫苗免疫效果的作用。DNA疫苗能诱导产生保护性反应 ,为今后IBD疫苗的研究开创了一条新的途径。The complete polyprotein(VP2/VP4/VP3)gene of an infectious bursal disease virus(IBDV-ZJ2000) was amplified by long and accurate PCR in a single step,then cloned,sequenced,and inserted into pCI.The recombinant plasmid was co-transfected the Vero cell mediated by lipofectin resulting in expressing the immuno-reactive polyprotein.An efficient method was developed to prepare DNA vaccine using immune stimulating complexes(ISCOM) as adjuvant.14-day-old SPF chickens were vaccinated with DNA vaccine by different dosages and delivery routes to examine their immunogenicity.The results showed that DNA vaccine delivered by joined intramuscular and intradermal routes elicited much higher protective response than those of oral and eyedrop routes.Most of chickens vaccinated with large dosage of DNA vaccine(>200μg) could protect from IBDV-BC6/85 challenge,however,those vaccinated with DNA under 100μg failed.The efficacy of secondary immunization was more optimal than that of primary immunization.Compared with traditional attenuated vaccines,B87 and D78,the neutralization antibody of DNA vaccine was much lower,but lasted longer.Low antibody titer induced protective immunity against virulent IBDV may contribute to the induction of cellular immune response as well as humoral immune response.We also proved that ISCOM could improve the antibody response of DNA vaccine.

关 键 词：传染性法氏囊病病毒 多聚蛋白 DNA疫苗 免疫原性 中和抗体 免疫刺激复合物 ISCOM 

分 类 号：S852.659.4[农业科学—基础兽医学] S858.315.3[农业科学—兽医学]