McGarvey Michael Joseph, Iqbal Mohammed, Nastos Theodoros, Karayiannis Peter
Department of Medicine, Imperial College, Faculty of Medicine, St. Mary's Campus, London, United Kingdom.
Virus Res. 2008 Jul;135(1):181-6. doi: 10.1016/j.virusres.2008.03.013. Epub 2008 May 1.
The extent of genetic variability following acute infection of tamarins with GB virus B (GBV-B) is not known. In this study we attempted to define the quasispecies variation of GBV-B 17 days post-infection, by PCR amplification of GBV-B RNA extracted from serum and liver. Cloning followed by sequencing revealed a small number of changes in the three regions studied, namely the 5' untranslated region, E2 and NS3. Moreover, there was no region of high amino acid variability in E2, akin to hypervariable region 1 of hepatitis C virus. This was further confirmed by analysing sequences from two additional animals obtained at a similar time point post-infection. Nevertheless, it was apparent that different variants with one or two amino acid substitutions in the region studied had been selected when comparing the sequences from the three animals. This restricted sequence variation of GBV-B during acute hepatitis may explain the infrequent progression of the infection to a chronic stage.
绢毛猴急性感染GB病毒B（GBV - B）后的基因变异性程度尚不清楚。在本研究中，我们试图通过对感染后17天从血清和肝脏中提取的GBV - B RNA进行PCR扩增，来确定GBV - B的准种变异情况。克隆后测序显示，在所研究的三个区域，即5'非翻译区、E2和NS3中，有少量变化。此外，E2区不存在类似于丙型肝炎病毒高变区1那样的高氨基酸变异性区域。对感染后相似时间点获得的另外两只动物的序列进行分析，进一步证实了这一点。然而，比较三只动物的序列时明显发现，在所研究区域中存在具有一两个氨基酸替换的不同变体。GBV - B在急性肝炎期间这种有限的序列变异可能解释了该感染很少进展到慢性阶段的原因。
