摘要
目的评价以乙型肝炎病毒核心区为载体的HBsAg“a”决定簇编码基因的基因免疫效果。方法分别使用将编码截短型乙肝病毒核心抗原的主要免疫显性区替换为表面抗原“a”决定簇嵌合基因的真核表达质粒；编码表面抗原“a”决定簇部分的质粒和空载体为免疫原，免疫4～6周龄的BALB／c小鼠，定期采血检测体液免疫应答情况并取免疫后小鼠脾细胞进行淋巴细胞增殖试验。结果嵌合质粒免疫组针对HBsAg的体液应答水平低于非嵌合质粒免疫组，且未引起较强的HBcAb体液免疫应答，但获得了较强的HBcAg和HBsAg特异性的细胞应答。结论该嵌合质粒作为基因疫苗可以引起较强的HBcAg和HBsAg特异性的细胞应答并诱导小鼠产生HBsAb。HBcAg在一定程度上可以增强对插入抗原的免疫应答，是一种有效的病毒样颗粒载体；该嵌合基因有望成为一种新的慢性HBV感染的治疗性基因疫苗。
Objective To evaluate the immunologic effect of the chimeric plasmid encoding HBsAg ＂a＂ determinant region with truncated HBV core gene as vector. Methods Using the chimeric plasmid encoding truncated HBV core protein and HBsAg ＂a＂ determinant, nonchimeric plasmid and pcDNA3 vector as immunogen to inoculate BAL B/c mice of 4 - 6 weeks old separately. After with a injection of cardiotoxin in legs of mice 7 days before, 100 7g plasmid was inoculated to each mouse. HBsAb and HBcAb were measured with indirect enzyme linked immunosorbent assay （ELISA） at different time points and performed lymphocyte proliferation test with spleen ceils. Results The protective humoral response to HBsAg of chimeric plasmid immunized group was weaker than nonchimeric group; the anti-HBc response was very weak. But the specific lymphocyte proliferation activity was considerable strong when use HBsAg or HBcAg as stimulator in chimeric plasmid immunized mice. Conclusion As a kind of genetic vaccine, this chimeric plasmid induces effective HBsAb response but no significaut HBcAb response, on the other hand it clicits stronger HBcAg and HBsAg specific T lymphocyte response in inoculated mice. HBcAg is an kind of effective virus-like particle vector as it can enhance the immune response to the expressed antigen. The chimeric plasmid could hopeful be a therapeutic vaccine candidate for chronic HBV infection.
出处
《肝脏》
2007年第4期257-260,共4页
Chinese Hepatology
基金
973计划资助项目(2001CB510008)
关键词
乙型肝炎病毒
基因免疫
刺激指数
病毒样颗粒
hepatitis B virus
genetic immunization
stimulating index
virus-like particles
