Ou-Yang Pu, Hwang Lih-Hwa, Tao Mi-Hua, Chiang Bor-Luen, Chen Ding-Shinn
Graduate Institute of Immunology, College of Medicine, National Taiwan University, Taipei, Taiwan.
J Med Virol. 2002 Mar;66(3):320-8. doi: 10.1002/jmv.2148.
Hepatitis C virus (HCV) infection has become a critical public health problem worldwide. In Taiwan, it has been estimated that more than 300,000 people, 2% of the general population, have HCV infection. It has been well documented that direct delivery of gene intramuscularly can generate both humoral and cellular immunity, which more closely simulates the conditions of infection. In this study, female Balb/c mice immunized with HCV core plasmid DNA with or without adjuvant GM-CSF cytokine gene could induce both cellular immune response and HCV core-specific antibody titers after injection. Furthermore, the mice immunized with HCV core plus GM-CSF genes showed higher antibody titer and cytotoxic T cell activity compared to those of mice immunized with HCV core gene only (P < 0.05). To explore the effect of GM-CSF gene, the mice were immunized with reporter gene and cytokine gene plasmid. Increased levels of reporter protein and infiltrating cells around muscle tissue were noted. Moreover, the protein could be detected in inguinal node 24 hr after injection, especially in mice immunized with HCV/core plasmid plus GM-CSF gene. It was also observed that reporter protein expressing CD11c(+) dendritic cells could be seen in the inguinal node. These data suggest that the GM-CSF gene did enhance HCV core specific immune response when co-immunized with HCV core DNA plasmid. Although more studies are needed, dendritic cells that appeared around the naked DNA injection area and that local lymph nodes might play a critical role in the immune response induced by naked DNA immunization.
丙型肝炎病毒（HCV）感染已成为全球一个关键的公共卫生问题。在台湾，据估计超过30万人（占总人口的2%）感染了HCV。已有充分文献证明，基因肌内直接递送可产生体液免疫和细胞免疫，这更接近感染情况。在本研究中，用含或不含佐剂GM-CSF细胞因子基因的HCV核心质粒DNA免疫的雌性Balb/c小鼠在注射后可诱导细胞免疫反应和HCV核心特异性抗体滴度。此外，与仅用HCV核心基因免疫的小鼠相比，用HCV核心加GM-CSF基因免疫的小鼠显示出更高的抗体滴度和细胞毒性T细胞活性（P<0.05）。为了探究GM-CSF基因的作用，用报告基因和细胞因子基因质粒免疫小鼠。观察到肌肉组织周围报告蛋白水平和浸润细胞增加。此外，注射后24小时可在腹股沟淋巴结中检测到该蛋白，尤其是在用HCV/核心质粒加GM-CSF基因免疫的小鼠中。还观察到在腹股沟淋巴结中可见表达报告蛋白的CD11c(+)树突状细胞。这些数据表明，GM-CSF基因与HCV核心DNA质粒共同免疫时确实增强了HCV核心特异性免疫反应。尽管还需要更多研究，但出现在裸DNA注射区域周围的树突状细胞以及局部淋巴结可能在裸DNA免疫诱导的免疫反应中起关键作用。
