Department of Veterinary Pathology, University of Agricultural Sciences and Veterinary Medicine, 3-5 Calea Manastur, 400372, Cluj-Napoca, Romania.
Laboratory of Genomics, Biodiversity, Animal Breeding and Molecular Pathology, Institute of Life Sciences, University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca, Romania.
BMC Vet Res. 2020 Aug 17;16(1):296. doi: 10.1186/s12917-020-02521-1.
Ovine pulmonary adenocarcinoma (OPA) is a neoplastic disease caused by exogenous Jaagsiekte Sheep Retrovirus (exJSRV). The prevalence of JSRV-related OPA in Eastern European countries, including Romania is unknown. We aimed to investigate: the prevalence and morphological features of OPA (classical and atypical forms) in the Transylvania region (Romania), the immunophenotype of the pulmonary tumors and their relationships with exJSRV infection. A total of 2693 adult ewes slaughtered between 2017 and 2019 in two private slaughterhouses from Transylvania region (Romania) was evaluated. Lung tumors were subsequently assessed by cytology, histology, immunocytochemistry, immunohistochemistry, electron microscopy and DNA testing.
Out of 2693 examined sheep, 34 had OPA (1.26% prevalence). The diaphragmatic lobes were the most affected. Grossly, the classical OPA was identified in 88.24% of investigated cases and the atypical OPA in 11.76% that included solitary myxomatous nodules. Histopathology results confirmed the presence of OPA in all suspected cases, which were classified into acinar and papillary types. Myxoid growths (MGs) were diagnosed in 6 classical OPA cases and in 2 cases of atypical form. Lung adenocarcinoma was positive for MCK and TTF-1, and MGs showed immunoreaction for Vimentin, Desmin and SMA; Ki67 expression of classical OPA was higher than atypical OPA and MGs. JSRV-MA was identified by IHC (94.11%) in both epithelial and mesenchymal cells of OPA. Immunocytochemistry and electron microscopy also confirmed the JSRV within the neoplastic cells. ExJSRV was identified by PCR in 97.05% of analyzed samples. Phylogenetic analysis revealed the presence of the exJSRV type 2 (MT809678.1) in Romanian sheep affected by lung cancer and showed a high similarity with the UK strain (AF105220.1).
In this study, we confirmed for the first time in Romania the presence of exJSRV in naturally occurring OPA in sheep. Additionally, we described the first report of atypical OPA in Romania, and to the best of our knowledge, in Eastern Europe. Finally, we showed that MGs have a myofibroblastic origin.
绵羊肺腺瘤病（OPA）是一种由外源性 Jaggsiekte 绵羊反转录病毒（exJSRV）引起的肿瘤性疾病。东欧国家（包括罗马尼亚）JSRV 相关 OPA 的流行情况尚不清楚。我们旨在研究：特兰西瓦尼亚地区（罗马尼亚）OPA（经典和非典型形式）的流行率和形态特征、肺肿瘤的免疫表型及其与 exJSRV 感染的关系。我们评估了 2017 年至 2019 年间在特兰西瓦尼亚地区（罗马尼亚）的两家私人屠宰场屠宰的 2693 只成年母羊。随后通过细胞学、组织学、免疫细胞化学、免疫组织化学、电子显微镜和 DNA 检测评估肺肿瘤。
在检查的 2693 只绵羊中，有 34 只患有 OPA（流行率为 1.26%）。膈叶是最常受影响的部位。大体上，在 88.24%的研究病例中发现了经典 OPA，在 11.76%的病例中发现了非典型 OPA，其中包括单发黏液瘤性结节。组织病理学结果证实所有疑似病例均存在 OPA，分为腺泡和乳头状类型。在 6 例经典 OPA 病例和 2 例非典型病例中诊断出黏液样生长物（MGs）。肺腺癌对 MCK 和 TTF-1 呈阳性，MGs 对波形蛋白、结蛋白和 SMA 呈免疫反应；经典 OPA 的 Ki67 表达高于非典型 OPA 和 MGs。OPA 的上皮和间充质细胞中均通过 IHC（94.11%）鉴定出 JSRV-MA。免疫细胞化学和电子显微镜也证实了肿瘤细胞内存在 JSRV。在分析的 97.05%样本中通过 PCR 鉴定出 exJSRV。系统发育分析显示，罗马尼亚患肺癌的绵羊中存在外源性 JSRV 2 型（MT809678.1），与英国株（AF105220.1）高度相似。
在这项研究中，我们首次在罗马尼亚确认了绵羊中存在外源性 JSRV 引起的 OPA。此外，我们描述了罗马尼亚首例非典型 OPA 的报告，据我们所知，这也是东欧首例。最后，我们表明 MGs 具有肌纤维母细胞起源。
