College of Animal Science, Yangtze University, No.88, Jingmi Road, Jingzhou 434025, China.
Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, No. 678, Haping Road, Harbin, China.
Vet Immunol Immunopathol. 2020 Dec;230:110143. doi: 10.1016/j.vetimm.2020.110143. Epub 2020 Oct 20.
During the past two decades, avian leukosis virus (ALV) caused tremendous economic losses to poultry industry in China. ALV-K as a newly found subgroup in recent years, which made the control and eradication of ALV more difficult as they were originated from the recombination of different subgroups. To date, specific rapid detection methods refer to ALV-K are still missing. Gp85 is the main structural protein of the virus, which mediates the invasion of host cells by the virus and determinates the classification of subgroups. In this study, we prepared a monoclonal antibody (Mab) named Km3 against Gp85 of ALV-K. Immunofluorescence assay showed that Km3 specifically recognized the strains of ALV-K rather than the strains of ALV-A or ALV-J. To explain the subgroups specificity of Km3, the epitope cognized by the Mab was identified by Western blotting using 15 overlapping fragments spanning the Gp85. Finally, the peptide AFGPRSIDTLSDWSRPQ was identified as the minimal linear epitope recognized by Km3. Alignment of Gp85 from different subgroups showed that the epitope was highly conserved among ALV-K strains, which was quite different from that of the strains from ALV -A, -B and -J. In conclusion, the Mab Km3 may serve as a useful reagent for ALV-K detection and diagnosis in the future.
在过去的二十年中，禽白血病病毒（ALV）给中国的家禽业造成了巨大的经济损失。ALV-K 是近年来新发现的亚群，由于它们起源于不同亚群的重组，使得 ALV 的控制和根除更加困难。迄今为止，针对 ALV-K 的特定快速检测方法仍然缺失。gp85 是病毒的主要结构蛋白，它介导病毒入侵宿主细胞，并决定亚群的分类。在本研究中，我们制备了一种针对 ALV-K 的 gp85 的单克隆抗体（Mab），命名为 Km3。免疫荧光分析表明，Km3 特异性识别 ALV-K 株，而不识别 ALV-A 或 ALV-J 株。为了解释 Km3 的亚群特异性，我们通过 Western blot 用 15 个跨越 gp85 的重叠片段鉴定了 Mab 识别的表位。最后，鉴定出最小线性表位为 AFGPRSIDTLSDWSRPQ。不同亚群的 gp85 序列比对表明，该表位在 ALV-K 株中高度保守，与 ALV-A、-B 和 -J 株的表位有很大的不同。综上所述，Mab Km3 可能成为未来 ALV-K 检测和诊断的有用试剂。
