摘要
目的评价融合蛋白基因质粒(pFP)联合在体电脉冲(EP)介导的HBVDNA疫苗(pS2.S)免疫HBV转基因(Tg)小鼠的治疗效果。方法HBVTg小鼠随机分成3组,每组5只,分别为pS2.S+pFP、pS2.S+pcDNA3.1免疫治疗和pcDNA3.1对照组,联合免疫质粒总剂量40μg/只,按1∶1比例混合接种。初次免疫后第4、8周分别进行第一、二次增强免疫,免疫前后分别检测血清学、组织学及HBV特异性免疫应答。结果HBVDNA血清定量检测结果,pS2.S+pFP组免疫第8周(13317±2539)拷贝/ml、第12周(6462±3359)拷贝/ml时分别较免疫前(36159±7769)拷贝/ml明显减低,差异具有统计学意义(P<0.01);pS2.S+pcDNA3.1组第4周(20618±9523)拷贝/ml及第8周(23818±5319)拷贝/ml时均较其免疫前水平(36090±4421)拷贝/ml明显降低(P<0.01),但不能持续到12周(27691±13071)拷贝/ml,并明显高于此时pS2.S+pFP组水平,差异有统计学意义(P<0.01);观察终点(12周)pS2.S+pFP组Tg小鼠个体血清HBVDNA及肝组织HBsAg表达水平降低的同时,伴随其血清ALT水平及HBsAg特异性IFN-γ分泌细胞数目的升高。结论Th1类细胞因子IL-2/IFN-γ融合蛋白基因表达质粒能够增强HBVDNA疫苗抑制Tg鼠HBVDNA复制和表达的治疗作用。
Objective To investigate the effect of interleukin-2 and interferon-γ fusion protein expressing plasmid （pFP） on therapeutic potency of in vivo electroporation （EP）-mediated HBV DNA vaccination （pS2.S） in HBV transgenic （Tg） mice. Methods 3 groups （5 Tg mice/group） of mice were immunized with （1） pS2.S＋pFP＋EP, （2） pS2.S＋pcDNA3.1＋EP, or （3） and pcDNA3.1＋EP, in a dose of total 40 μg of DNA/mouse, at a 1 ： 1 ratio for 3 times at week 0, 4, and 8. Serological, histological and HBsAg-specific immune responses analysis were performed to evaluate the efficacy. Results The therapeutic efficacy of a HBV DNA vaccine was enhanced by pFP in that we observed the persistent suppression of HBV DNA replication and expression in Tg mice until the endpoint of the study when the more profound suppressive effects were accompanied by favorable INF-γ T cell responses and serum ALT elevation. Conclusion The results suggest that IL-2 and IFN-γ as the Th1-type cytokines in the form of a fusion protein, can enhance the therapeutic efficacy of HBV DNA vaccine by persistently suppressing the HBV DNA replication and expression.
出处
《热带医学杂志》
CAS
2008年第5期408-411,435,F0004,共6页
Journal of Tropical Medicine
基金
国家863项目(No.2002AA2Z3317)
