Dipartimento di Produzioni Animali, Epidemiologia, Ecologia, Facoltà di Medicina Veterinaria, Università degli Studi di Torino, Via Leonardo da Vinci 44, 10095 Grugliasco, TO, Italy.
Vet Microbiol. 2010 Jul 29;144(1-2):24-31. doi: 10.1016/j.vetmic.2009.12.020. Epub 2009 Dec 23.
The highly divergent SRLV genotype E has recently been characterized in Italy as a low pathogenic caprine lentivirus in the Roccaverano breed. The availability of a genotype specific diagnostic test based on a comparative assay, using a combination of genotype specific recombinant antigens allows a wide serosurvey in other goat populations. The island of Sardinia still has the highest small ruminant population of any Italian region and crossbreeding has been limited to goats, mainly with the Maltese breed. A serological survey was carried out on sheep flocks and goat herds, using individual sera as well as a bulk milk-adapted procedure. Genotype E was identified in more than 50% of goat herds and none of the sheep flocks thus supporting the idea that this genotype is specifically associated with the goat species. The full-length proviral sequence of a Sardinian isolate revealed and confirmed the deletion of dUTPase subunit and the absence of both vpr gene and the 71bp repeat of the LTR. Genetic similarity of this isolate with the prototype strain Roccaverano was not more than 84%, supporting the designation of two subtypes within genotype E. Nevertheless, in vitro properties of the Sardinian strain were different from those of the Roccaverano strain in terms of ability to infect synovial membrane and produce syncitia. Remarkable differences in the HV1 and HV2 of the env gene were recorded, with the Sardinian isolate displaying sequence motif more similar to arthritic strains. Data presented suggest diffusion of genotype E is wider than previously thought.
最近，意大利在罗卡维拉诺品种中发现了一种高度分化的 SRLV 基因型 E，它是一种低致病性的山羊慢病毒。由于基于比较分析的基因型特异性诊断测试的可用性，使用组合的基因型特异性重组抗原，可以在其他山羊群体中进行广泛的血清学调查。撒丁岛仍然是意大利任何地区小反刍动物数量最多的岛屿，杂交仅限于山羊，主要与马耳他品种杂交。对绵羊群和山羊群进行了血清学调查，使用个体血清和批量牛奶适应程序。在超过 50%的山羊群中发现了基因型 E，而绵羊群中没有发现，这支持了这种基因型与山羊物种密切相关的观点。对撒丁岛分离株的全长前病毒序列进行了鉴定和证实，该序列缺失了 dUTPase 亚基，并且 vpr 基因和 LTR 的 71bp 重复序列均不存在。该分离株与原型菌株罗卡维拉诺的遗传相似性不超过 84%，支持在基因型 E 内指定两种亚型。然而，该撒丁岛分离株的体外特性与罗卡维拉诺分离株不同，其感染滑膜和产生合胞体的能力不同。env 基因的 HV1 和 HV2 记录了显著的差异，撒丁岛分离株显示出与关节炎株更相似的序列基序。所提供的数据表明，基因型 E 的传播范围比以前想象的要广泛。
