Thomas H C, Carman W F
Department of Medicine, St Mary's Hospital Medical School, Imperial College, London University, England.
Prog Liver Dis. 1992;10:239-51.
The appearance of replication-competent variants of HBV with mutations in the envelope and precore/core proteins emphasizes that these proteins are the focus of immune selection pressure in the human host. The sequence and speed of application of the multiple selection pressures (humoral and possibly cellular) will determine the virological and clinical outcome. When these variant viruses are passed to a new host, in the absence of the immune selection pressures or modified immune pressures which resulted in their selection, a clinical picture different from that seen in the original host may emerge. Although HBV would seem to be highly evolved, it still seems to have the capacity for further diversity. A number of the reported variations have an obvious clinical relevance, but others do not, and further study is required to elucidate their importance. Whether they represent independently transmissible strains of HBV or are all selected during the course of infection, only to be lost in favor of the original strain on infection of another host, also remains to be determined.
乙型肝炎病毒（HBV）包膜蛋白和前核心/核心蛋白发生突变的具有复制能力的变异体的出现，强调了这些蛋白是人类宿主中免疫选择压力的焦点。多种选择压力（体液免疫以及可能的细胞免疫）的施加顺序和速度将决定病毒学和临床结局。当这些变异病毒传播到新宿主时，由于缺乏导致其产生的免疫选择压力或经过改变的免疫压力，可能会出现与原始宿主不同的临床症状。尽管HBV似乎已经高度进化，但它似乎仍有进一步产生多样性的能力。一些已报道的变异具有明显的临床相关性，但其他变异则不然，需要进一步研究以阐明它们的重要性。它们是代表独立可传播的HBV毒株，还是在感染过程中均被选择，却在感染另一宿主时被原始毒株取代，这些都有待确定。
