Hepatocarcinogenesis in transgenic mice carrying hepatitis C virus cDNA

1转基因小鼠的表达分析我们分析了5株携带丙型肝炎病毒（HCV）全基因组的转基因小鼠，A44、A39和A48受小鼠白蛋白增强子/启动子控制，S2和S5受SR_α启动子控制。17只A44中，1只12月龄时肝脏有HCVmRNA表达，12只21月龄时肝脏有HCVmRNA表达。A39和A48小鼠的肝脏中均表达HCV转基因，但S2和S5小鼠均不表达。实时荧光定量PCR结果显示，每1 μg总RNA中可表达50 ~ 4000个拷贝的HCV RNA。HCVmRNA表达定位于肝组织。在肝脏中检测到低于HCV核心蛋白的检测限（5 pg/mg蛋白）。这些转基因小鼠A39、A44和A48表现出与慢性丙型肝炎患者相似的HCV表达水平，这与其他高水平表达HCV的转基因小鼠不同。 ...更多信息 转基因小鼠肝脏离子A39、A44和A48转基因小鼠肝脏可见炎性细胞浸润和点状坏死。在21月龄时，A39和A44中点状坏死灶的数量显著高于非转基因小鼠。转基因组与非转基因组肝脏脂肪变性不明显。至21月龄才出现肝纤维化和肿瘤性病变。3转基因小鼠肝脏的分子发病机制实时荧光定量RT-PCR检测结果显示，在转基因小鼠肝脏中，干扰素诱导基因、细胞周期相关基因等mRNA表达上调，与HCV感染患者的情况相同，与弱毒肝炎患者相似。然而，小鼠的抗病毒免疫应答远远低于患者，这表明在这些HCV转基因小鼠中引入抗病毒免疫系统应该是建立肝癌模型所必需的。少

1 Expression analysis of transgenic miceWe analyzed 5 lines of transgenic mice carrying the whole genome of hepatitis C virus (HCV); A44, A39 and A48 were controlled under the mouse albumin enhancer/ promoter; S2 and S5 were under the SR_α promoter. The HCV mRNA was expressed in the liver of one of 17 A44 at the age of 12 months and 12 of 17 A44 at the age of 21 months. All mice of A39 and A48 expressed the HCV transgene in the liver, but both S2 and S5 did not. The mRNA was 9.4 kb in length, and the real-time PCR revealed that 50 to 4000 copies of HCV RNA were expressed in 1 μg of total RNA. The expression of HCV mRNA seemed to be localized in the liver tissue. Less than the detection limit of HCV core protein (5 pg/mg protein) was detected in the liver. These transgenic mice A39, A44 and A48 showed the similar level of HCV expression to that of patients with chronic hepatitis C, that is different from other transgenic mice with the high level of HCV expression.2 Histological examinat … More ion of transgenic mouse liverInflammatory cell infiltration and spotty necrosis were observed in transgenic mouse liver of A39, A44 and A48. The number of spotty necrosis foci was significantly higher in A39 and A44 than non-transgenic mice at the age of 21 months. The fatty change of liver was not significant between transgenics and non-transgenics. Liver fibrosis and tumorous lesion were not observed until 21 months old. HCV antibodies were not detected in serum of the mice.3 Molecular pathogenesis of transgenic mouse liverReal-time RT-PCR of mRNA revealed that mRNAs such as interferon-inducible genes and cell cycle-related genes were up-regulated in transgenic mouse liver, that is observed in patients with HCV infection.Thus, these transgenic mice were similar to patients with weak hepatitis. Anti-viral immune response of the mice, however, was so much less than that of patients, suggesting that the introduction of anti-viral immune system to these HCV transgenic mice should be required for establishing a model of hepatocarcinogenesis. Less