含CpG序列PRRSV ORF5基因真核质粒对猪体免疫作用研究  

Study on immunological responses to eukaryotic expression vector containing PRRSV ORF5 and CpG motifs

作　　者：温建新[1] 王金宝[2] 

机构地区：[1]青岛农业大学动物科技学院,青岛266109 [2]山东省农业科学院,济南250000

出　　处：《中国免疫学杂志》2008年第10期925-930,共6页Chinese Journal of Immunology

基　　金：山东省自然科学基金项目(NoZ2003D01)

摘　　要：目的:为了增强猪繁殖与呼吸综合征病毒(PRRSV)DNA疫苗免疫效力,以pVAX1为真核表达载体,以PRRSV ORF5基因为目的基因,构建了含有CpG和PRRSV ORF5的真核表达质粒CpG-pVAX1-ORF5,并在猪体进行了免疫试验。方法:检测猪PRRSV的特异性抗体滴度、IL-2水平以及淋巴细胞增殖反应(MTT法)水平,并做了攻毒保护试验。结果:试验结果表明本试验构建的含CpG基序真核重组表达质粒CpG-pVAX1-ORF5能诱导产生针对PRRSV的体液免疫与细胞免疫(显著的淋巴细胞增殖反应水平)。攻毒结果表明CpG-pVAX1-ORF5组能够有效地抵抗经鼻攻毒,可以保护猪轻微病毒血症,比对照组减少80%,也不表现临床症状,对肺的损害能提供部分保护。结论:CpG的加入可使免疫猪的病变减轻或消失。从而表明含有CpG-ODN能作为PRRSVDNA疫苗的有效佐剂。Objective：To enhance the immune efficiency of porcine reproductive and respiratory syndrome virus（PRRSV）DNA vaccine,the ORF5 genes were used as candidate genes to construct the recombinant plasmids CpG-pVAX1-ORF5 by pVAX1 as eukaryotic expression vector.The aim is to analyze the immune responses and the effects of CpG-ODN induced by GP5 recombinant plasmids of PRRSV.Methods：Piglets were immunized with recombinant DNA plasmids which expressed PRRSV GP5 for three inoculations.The PRRSV antibody in serum,the concentration of IL-2 and the lymphocyte proliferation test（MTT） in peripheral blood of vaccinated piglets were detected.The vaccinated pigs were challenged intranasally with PRRSV SD2.Results：GP5 DNA immunization with CpG resulted in the production of both PRRSV antibodies and cellular immune（a significant enhancement of a lymphoproliferative response ）.The CpG-pVAX1-ORF5 was showed significantly better protection from the PRRSV challenge compared with the control plasmid.This immune response was characterized by a significantly decreased frequency of viraemia with decrease of 80% compared with the control group.There were little clinical symptoms and protection in some extent from lung damage.Conclusion：The results indicate that CpG-ODN could be used as immune adjuvant of PRRSV DNA vaccine.

关 键 词：猪繁殖与呼吸综合征病毒 ORF5基因 CPG DNA免疫 

分 类 号：S828[农业科学—畜牧学]