摘要
人类疱疹病毒6型(Human herpesvirus 6,HHV-6)是双链DNA病毒,其原发感染引起婴幼儿急疹,潜伏感染后的再激活亦引起多种严重疾患。近来,该病毒特有的潜伏感染形式—病毒基因组的宿主染色体整合(包括机制及临床相关性)被不断报道。HHV-6基因组的末端区域含有端粒重复序列,病毒基因组通过该重复序列整合到宿主细胞染色体中建立潜伏感染。当宿主免疫力受到抑制时,整合于宿主染色体上的病毒基因组会再次活化,引起疾患。本文综述了HHV-6基因组染色体整合的主要机制及临床意义。
Primary infection by the double-stranded DNA virus human herpesvirus 6(HHV-6)causes exanthem subitum,after which it establishes lifelong latency in an unique form,integrating its viral genome into the host genome. Infective HHV-6 can be reactivated from the integrated viral genome and leads to some severe diseases. HHV-6 possesses telomeric repeats at the terminal regions of its genome,which facilitates the establishment of virus latency by site-specific integration in the telomere region of the host genome. Here,the mechanism of chromosomal integration and its clinical consequences are summarized.
引文
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