Holland J J, Grabau E A, Jones C L, Semler B L
Cell. 1979 Mar;16(3):495-504. doi: 10.1016/0092-8674(79)90024-2.
Persistent infection of BHK21 cells was established with cloned vesicular somatitis virus plus purified Dl particles and maintained in vitro for over 5 years. After 1 year of persistence, the infectious virus RNA genome had evolved several oligonucleotide map changes, and numerous changes had accumulated by 3.5 years. Additional evolution occurred by the fourth year and continued until the fifth year. In contrast, repeated passage of virus in acute infections of several cell types in vitro or in vivo did not lead to detectable oligonucleotide map changes. The short Dl particle originally used to co-infect with infectious virus in establishing persistent infection has been displaced by an ever present and constantly changing population of other Dl particles of differing sizes and radically differing oligonucleotide maps. We conclude that the genomes of both infectious VSV and its Dl particles undergo continuous evolutionary change during years of persistence. In the infectious virus, these changes involve hundreds of mutations which are usually expressed as poorly replicating, temperature-sensitive, small plaque mutants. These are stable mutants which do not revert to wild-type when passaged repeatedly in acute infections at 37 or 33 degrees C. It appears that the sequestered intracellular environment of persistently infected cells favors rapid and continuous virus evolution.
用克隆的水疱性口炎病毒加纯化的缺陷病毒颗粒建立了BHK21细胞的持续感染，并在体外维持了5年多。持续感染1年后，感染性病毒RNA基因组发生了几个寡核苷酸图谱变化，到3.5年时积累了许多变化。到第四年又发生了进一步的进化，并持续到第五年。相比之下，病毒在体外或体内几种细胞类型的急性感染中反复传代并未导致可检测到的寡核苷酸图谱变化。最初用于在建立持续感染时与感染性病毒共同感染的短缺陷病毒颗粒已被一群不断存在且不断变化的其他缺陷病毒颗粒所取代，这些颗粒大小不同，寡核苷酸图谱也截然不同。我们得出结论，感染性水疱性口炎病毒及其缺陷病毒颗粒的基因组在多年的持续感染过程中都经历了持续的进化变化。在感染性病毒中，这些变化涉及数百个突变，这些突变通常表现为复制能力差、温度敏感、小蚀斑突变体。这些是稳定的突变体，当在37或33摄氏度的急性感染中反复传代时不会回复为野生型。看来持续感染细胞的隔离细胞内环境有利于病毒的快速和持续进化。
