Bovine Viral Disease Unit, Division of Viral Disease and Epidemiology, National Institute of Animal Health, National Agriculture and Food Research Organization, 3-1-5 Kannondai, Tsukuba, Ibaraki, 305-0856, Japan.
Arch Virol. 2021 Mar;166(3):841-851. doi: 10.1007/s00705-020-04945-4. Epub 2021 Jan 24.
Enzootic bovine leukosis (EBL) is a malignant B-cell lymphoma of cattle caused by infection with bovine leukemia virus (BLV). It is defined by clonal and neoplastic expansion of BLV-infected B cells. Currently, multiple examinations are able to comprehensively diagnose this condition. Inverse polymerase chain reaction (PCR) is a useful method to determine retrovirus integration sites. Here, we established a simplified inverse PCR method, involving the evaluation of clonality and similarity of BLV integration sites, to clinically diagnose EBL, and we also assessed its reliability. We found that the novel BLV inverse PCR could detect clonal expansion of infected cells even if they constituted only 5% of the total number of cells, while not amplifying any fragments from BLV-uninfected cells, thus confirming its sufficient sensitivity and specificity for use in EBL diagnosis. Furthermore, 50 clinical cases of bovine leukemia were analyzed using BLV inverse PCR and other PCR-based methods, wherein our method most efficiently determined virus-dependent bovine leukemia, including unidentified clinical cases observed in a previous report. Following further clinical investigations to enhance its reliability, the proposed BLV inverse PCR method has the potential to be applied to EBL diagnosis.
牛传染性白血病（EBL）是一种由牛白血病病毒（BLV）感染引起的牛恶性 B 细胞淋巴瘤。它的特征是 BLV 感染的 B 细胞的克隆性和肿瘤性扩张。目前，多种检查能够全面诊断这种疾病。反转录聚合酶链反应（PCR）是一种确定逆转录病毒整合位点的有用方法。在这里，我们建立了一种简化的反转录 PCR 方法，用于评估 BLV 整合位点的克隆性和相似性，以临床诊断 EBL，并评估其可靠性。我们发现，新型 BLV 反转录 PCR 可以检测到受感染细胞的克隆性扩张，即使它们只占细胞总数的 5%，而不会扩增任何 BLV 未感染细胞的片段，从而证实其在 EBL 诊断中的足够灵敏度和特异性。此外，我们使用 BLV 反转 PCR 和其他基于 PCR 的方法分析了 50 例牛白血病临床病例，我们的方法最有效地确定了病毒依赖性牛白血病，包括之前报告中观察到的不明原因的临床病例。进一步的临床研究以提高其可靠性后，该 BLV 反转 PCR 方法具有应用于 EBL 诊断的潜力。
