Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
Division of Genomics Research, Life Science Research Center, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
Viruses. 2022 May 11;14(5):1022. doi: 10.3390/v14051022.
Enzootic bovine leukosis (EBL) is a disease caused by bovine leukemia virus (BLV); only a small percentage of BLV-infected cattle develop EBL and present with B-cell lymphosarcoma. There is no vaccine against BLV, treatment for EBL, or method for predicting the possibility of EBL onset, thus making EBL control difficult. Herein, to explore biomarkers for EBL in milk, we examined the mRNA profiles of small extracellular vesicles (sEVs) in milk from four BLV-uninfected and four EBL cattle by microarray analysis. It was revealed that 14 mRNAs were encapsulated in significantly higher quantities, and these mRNAs were therefore selected as biomarker candidates. Primers for these mRNAs were designed, and nine primer sets were available for quantitative real-time PCR. Nine mRNAs were evaluated for their availability as biomarkers for EBL using sEVs from newly-collected milk of 7 uninfected and 10 EBL cattle. The quantities of eight mRNAs (, , , , , , , and were significantly higher in milk sEVs of EBL cattle than in those of uninfected cattle. Therefore, our findings indicate that these eight mRNAs in milk sEVs can be used as potential EBL biomarkers with combination use, although single mRNA use is not enough. Consequently, cattle at risk of EBL onset can be identified by monitoring the fluctuation in quantities of these mRNAs in milk before they develop EBL.
牛白血病（EBL）是由牛白血病病毒（BLV）引起的疾病；只有一小部分 BLV 感染的牛会发展为 EBL，并表现出 B 细胞淋巴肉瘤。目前尚无 BLV 疫苗、EBL 治疗方法或预测 EBL 发病可能性的方法，因此 EBL 控制较为困难。在此，为了探索乳中的 EBL 生物标志物，我们通过微阵列分析检查了来自 4 头 BLV 未感染和 4 头 EBL 牛的乳中小细胞外囊泡（sEV）的 mRNA 谱。结果显示，14 种 mRNA 以更高的量被包裹，因此这些 mRNA 被选为生物标志物候选物。为这些 mRNA 设计了引物，有 9 个引物对可用于定量实时 PCR。使用新收集的 7 头未感染和 10 头 EBL 牛的乳 sEV，评估了 9 个 mRNA 作为 EBL 生物标志物的可用性。在 EBL 牛的乳 sEV 中，8 种 mRNA（、、、、、、和的含量明显高于未感染牛。因此，我们的研究结果表明，这些 8 种在乳 sEV 中的 mRNA 可以作为潜在的 EBL 生物标志物与联合使用，尽管单独使用单个 mRNA 还不够。因此，可以通过监测这些 mRNA 在牛奶中的数量波动来识别有 EBL 发病风险的牛，然后再发生 EBL。
