VIRUS OF HEPATITIS B

乙肝病毒是引起肝病的重要原因，包括 男性患上了肝癌。它是一种病毒家族的成员，这种病毒具有 有趣的结构、复制方式和生物学特性。我们 建议通过综合分析研究乙肝病毒在肝癌中的作用 从两株病毒中克隆出带有侧翼细胞DNA的病毒DNA序列 肝细胞癌(HCC)，每个都有单一的整合部位。我们 还将进一步研究NIH 3T3细胞的转化情况 克隆了HBVdna二聚体和HBVdna的1850bpBamHI片段 肝细胞癌。我们还将研究肝再生对病毒的影响 整合与肝癌的形成。我们将进一步表征高分子结构 在血浆病毒粒子中发现重量HBVDNA形式(5kd和9kd)。决赛 目标是研究一种病毒疫苗策略，通过这种策略，相关的病毒 抗原由肠道细菌菌株表达，从而导致免疫 当活细菌通过口腔摄入时，会产生反应，但不会引起疾病。 尽管这种方法可能会为ENTERIC提供特殊优势 病原体，如轮状病毒，对局部肠道免疫很重要， 该方法对其他药物如乙肝病毒也同样有效。 只有系统免疫才是重要的。我们已经为人类引入了 乙肝表面抗原和核心抗原与轮状病毒VP7 转化到质粒表达载体中，实现了乙肝表面抗原和 轮状病毒VP7为融合蛋白，HBcAg为离散多肽。 Coli.我们建议优化这些抗原在大肠杆菌中的表达； 将杂交质粒导入伤寒沙门氏菌Ty 21a和S。 鼠伤寒沙门氏菌1479(毒力减弱的突变体，并成功使用 作为活的口服沙门氏菌疫苗)；并测试转化的沙门氏菌 病毒抗原在小鼠体内的表达和诱导免疫反应的能力。 长期目标是在人体内接种轮状病毒和乙肝病毒的口服活疫苗。

Hepatitis B virus (HBV) is an important cause of liver disease including liver cancer in man. It is a member of a family of viruses which have interesting structure, mode of replication and biological properties. We propose to study the role of HBV in liver cancer by analyzing integrated viral DNA sequences with flanking cellular DNA cloned from two hepatocellular carcinomas (HCC), each with single integration sites. We will also further investigate NIH 3T3 cell transformation observed with a cloned HBV DNA dimer, an 1850 bp BamHI fragment of HBV DNA and DNA from HCC. We will also investigate the effect of liver regeneration on viral integration and HCC formation. We will further characterize high molecular weight HBV DNA forms (5 and 9 kd) found in virions from plasma. A final goal is to investigate a viral vaccine strategy by which relevant viral antigens are expressed by enteric bacterial strains which result in immune responses but not disease when live bacteria are ingested by mouth. Although this approach might offer a particular advantage for enteric pathogens such as rotavirus for which local enteric immunity is important, the approach could be equally effective for other agents such as HBV for which only systemic immunity is important. We have introduced genes for hepatitis B surface (HBsAg) and core (HBcAg) antigens and rotavirus VP7 into plasmid expression vectors and have achieved expression of HBsAg and rotavirus VP7 as fusion proteins and HBcAg as a discrete polypeptide in E. coli. We propose to optimize expression of these antigens in E. coli; introduce the hybrid plasmids into Salmonella typhi strain Ty 21a and S. typhimurine 1479 (mutants with attenuated virulence and successfully used as live, oral Salmonella vaccines); and test the transformed Salmonella for viral antigen expression and ability to induce immune responses in mice. The long-term goal is live oral vaccines for rotavirus and HBV in man.