摘要
目的 利用DHBV感染鸭模型 ,研究鸭IFN γ真核表达质粒作为免疫佐剂对DNA疫苗诱导免疫应答的影响和预防DHBV感染的作用。方法 用DuIFN γ真核表达质粒与DHBpreS SDNA疫苗共免疫 ,或用DHBpreS SDNA疫苗单独免疫正常幼鸭 ,检测经免疫前后鸭PBMC表达DuIFN γ的mRNA水平 (半定量竞争性RT PCR)、诱生的抗体水平 (ELISA)、病毒攻击免疫鸭后血清和肝脏中的病毒DNA变化 (斑点和Southern印迹核酸杂交 )。结果 IFN γ表达质粒作为免疫佐剂 ,可以增强DNA疫苗诱导的鸭PBMCIFN γ的mRNA表达水平。用大剂量病毒攻击免疫鸭的结果显示 ,用DuIFN γ表达质粒和DHBpreS SDNA疫苗共免疫鸭清除DHBV的速度 ,明显比仅用DHBpreS SDNA疫苗免疫鸭清除病毒的速度快 ,肝脏中DHBV总DNA和共价闭环DNA(cccDNA)的量也低于DHBpreS SDNA单独免疫组。结论 IFN γ真核表达质粒作为免疫调节佐剂在DNA免疫中具有潜在的应用价值。
Objective DHBV (duck hepatitis B virus)-infected duck is an animal model for the investigation of molecular mechanism of host defense against HBV infection. In the present study, we used the animal model to observe the effects of duck IFN-γ (DuIFN-γ) eukaryotic expression plasmid on the immune responses induced by DNA vaccines and protection of duck from DHBV challenge. Methods Ducks were co-immunized with DHBpreS/S DNA vaccine and DuIFN-γ plasmid or the DNA vaccine alone. DuIFN-γ mRNA in PBMC from immunized ducks was detected by semi-quantitative competitive RT-PCR. The anti-preS/S was titrated by ELISA. DHBV DNA in sera and in the liver were detected by dot or Southern blot hybridization after challenge with high dose of DHBV. Results The results showed that in the ducks co-immunized with DuIFN-γ plasmid as an adjuvant, expression of DuIFN-γ mRNA was higher than those being immunized with DHBpreS/S DNA alone. After high dose of DHBV challenged, in the ducks co-immunized with DNA vaccine an DuIFN-γ plasmid, clearance of DHBV from sera was faster, total DNA and cccDNA were much less in the liver than in those with DHBpreS/S DNA immunization alone. Conclusion DuIFN-γ will be useful to improve the efficacy of DNA vaccine against DHBV infection.
出处
《中华微生物学和免疫学杂志》
CAS
CSCD
北大核心
2003年第7期529-533,共5页
Chinese Journal of Microbiology and Immunology
基金
国家 973资助项目 (G19990 5 410 5 )
国家自然科学基金资助项目 ( 3 0 0 70 693 )
