Seifer M, Heermann K H, Gerlich W H
Department of Medical Microbiology, University of Göttingen, Federal Republic of Germany.
Virology. 1990 Nov;179(1):300-11. doi: 10.1016/0042-6822(90)90298-6.
Permanent murine fibroblasts (LTK-) were transfected with a dimer of hepatitis B virus (HBV) DNA and a neomycin resistance gene which were both linked to the simian virus 40 (SV40) early promoter/enhancer. One of the stably transfected clones, LTK4/36, which secreted HBsAg, HBeAg, and HBV DNA was further analyzed. It contained eight to nine copies of integrated HBV DNA per haploid genome and low amounts of episomal HBV DNA. The secreted viral DNA was covalently linked to protein and was associated with particles which had the characteristic density of natural virions from serum of human viremic carriers. The particles contained an endogenous DNA polymerase, small and middle surface proteins, but in contrast to natural virions very little core protein and large surface protein. Instead of core protein, they contained incompletely processed HBe protein which is colinear to core protein. The fibroblast-derived virions were less stable than virions from human carriers or from transfected hepatoma cells. After several days of storage, their DNA was only partially protected against DNase. Obviously, nonhepatic cells can express HBV-like particles, even if liver-dependent gene products like large surface protein and core protein are missing.
将乙肝病毒（HBV）DNA二聚体和新霉素抗性基因转染到永久性鼠成纤维细胞（LTK-）中，二者均与猿猴病毒40（SV40）早期启动子/增强子相连。对其中一个稳定转染的克隆LTK4/36进行了进一步分析，该克隆分泌乙肝表面抗原（HBsAg）、乙肝e抗原（HBeAg）和HBV DNA。每个单倍体基因组含有8至9个整合的HBV DNA拷贝以及少量的游离型HBV DNA。分泌的病毒DNA与蛋白质共价连接，并与具有人类病毒血症携带者血清中天然病毒粒子特征密度的颗粒相关联。这些颗粒含有内源性DNA聚合酶、小分子和中分子表面蛋白，但与天然病毒粒子相比，核心蛋白和大分子表面蛋白很少。它们含有的不是核心蛋白，而是与核心蛋白共线性的未完全加工的HBe蛋白。成纤维细胞衍生的病毒粒子比来自人类携带者或转染肝癌细胞的病毒粒子稳定性差。储存几天后，其DNA仅受到部分保护，免受DNA酶的作用。显然，即使缺少如大分子表面蛋白和核心蛋白等肝脏依赖性基因产物，非肝细胞也能表达类似HBV的颗粒。
