Quérat G, Barban V, Sauze N, Filippi P, Vigne R, Russo P, Vitu C
J Virol. 1984 Nov;52(2):672-9. doi: 10.1128/JVI.52.2.672-679.1984.
Ovine and caprine lentiviruses share the capacity to induce slowly progressive and inflammatory diseases of the central nervous system (leukoencephalitis or visna), lungs (progressive pneumonia or maedi), and joints (arthritis) in their natural hosts. Studies on their replication indicated that ovine lentiviruses and caprine arthritis-encephalitis virus (CAEV) recently isolated in the United States establish persistent infection in ovine and caprine fibroblasts, whereas older prototype ovine lentiviruses such as Icelandic visna virus or American progressive pneumonia virus irreversibly lyse fibroblast cultures. Since all of the recent isolates were found to be persistent, Narayan et al. (J. Gen. Virol. 59:345-356, 1982) concluded that the highly lytic viruses were only tissue-culture-adapted strains. In the present report, we isolated new ovine lentiviruses from French sheep with naturally occurring progressive pneumonia which are either highly lytic (five isolates), as are the Icelandic strains of visna virus, or persistent (one isolate), as are CAEV or American persistent ovine lentiviruses. Protein and nucleic acid content analyses of these new highly lytic (type I) and persistent (type II) isolates indicated that type I and type II ovine lentiviruses were genetically distinct, type I and type II viruses being closely related to the Icelandic strains of visna virus and to CAEV, respectively. We conclude that (i) highly lytic ovine lentiviruses, such as the Icelandic prototype strains of visna virus and persistent lentiviruses more related to CAEV, are naturally present in the ovine species, and (ii) irreversible cell lysis induced by highly lytic viruses does not result from a tissue culture adaptation of field isolates that were originally persistent but is instead the consequence of a genetic content distinct from that of persistent viruses.
绵羊和山羊慢病毒能够在其自然宿主中引发中枢神经系统（白质脑炎或维斯纳病）、肺部（进行性肺炎或梅迪病）以及关节（关节炎）的缓慢进展性炎症疾病。对它们复制情况的研究表明，最近在美国分离出的绵羊慢病毒和山羊关节炎脑炎病毒（CAEV）能在绵羊和山羊成纤维细胞中建立持续性感染，而较老的原型绵羊慢病毒，如冰岛维斯纳病毒或美国进行性肺炎病毒，会不可逆地裂解成纤维细胞培养物。由于发现所有近期分离株都是持续性的，纳拉扬等人（《病毒学杂志》59:345 - 356, 1982）得出结论，高裂解性病毒只是组织培养适应株。在本报告中，我们从患有自然发生的进行性肺炎的法国绵羊中分离出了新的绵羊慢病毒，这些病毒要么像冰岛维斯纳病毒株一样具有高裂解性（五个分离株），要么像CAEV或美国持续性绵羊慢病毒一样具有持续性（一个分离株）。对这些新的高裂解性（I型）和持续性（II型）分离株的蛋白质和核酸含量分析表明，I型和II型绵羊慢病毒在基因上是不同的，I型和II型病毒分别与冰岛维斯纳病毒株和CAEV密切相关。我们得出结论：（i）高裂解性绵羊慢病毒，如冰岛原型维斯纳病毒株和与CAEV更相关的持续性慢病毒，天然存在于绵羊物种中；（ii）高裂解性病毒诱导的不可逆细胞裂解并非源于最初具有持续性的野外分离株的组织培养适应，而是源于与持续性病毒不同的基因组成。
