Institute of Special Wild Economic Animal and Plant Science, Chinese Academy of Agricultural Sciences, Changchun, China.
Key Lab of Zoonosis Research, Ministry of Education Institute of Zoonosis, Jilin University, Changchun, China.
Virol J. 2017 Sep 29;14(1):187. doi: 10.1186/s12985-017-0858-6.
The Nucleoprotein (NP) is the most abundant and highly immunogenic protein in canine distemper virus (CDV), playing an important role in CDV viral replication and assembly.
In this study, a specific monoclonal antibody, named C8, was produced against the NP protein C terminal (amino acids 401-523). A linear N protein epitope was identified by subjecting a series of partially overlapping synthesized peptides to enzyme-linked immunosorbent assay (ELISA) analysis.The results indicated that GDKYPIHFNDER was the minimal linear epitope that could be recognized by mAb C8. Sequence alignments demonstrated that this linear epitope is less conserved among three CDV genotypes. We next analyzed the level of conservation of the defined epitope in19 Chinese CDV clinical isolates, and it has one site variation in amino acid among these CDV isolations. 2 isolates have the amino acid mutations F451L, while one has P448Ssubstitution.Phylogenetic analysis showed the two isolates with F451Lsubstitution had a closer relationship in a virulent strain ZJ-7, so the epitope may be a significant tag associated with virus virulence.
This collection of mAb along with defined linear epitope may provide useful reagents for investigations of NP protein function and the development of CDV specific diagnostics.
核蛋白（NP）是犬瘟热病毒（CDV）中含量最丰富、免疫原性最强的蛋白，在 CDV 病毒复制和组装中发挥重要作用。
本研究针对 NP 蛋白 C 末端（氨基酸 401-523）产生了一种特异性单克隆抗体，命名为 C8。通过对一系列部分重叠合成肽进行酶联免疫吸附试验（ELISA）分析，确定了一个线性 N 蛋白表位。结果表明，GDKYPIHFNDER 是可被 mAb C8 识别的最小线性表位。序列比对表明，该线性表位在三种 CDV 基因型之间的保守性较低。我们随后分析了 19 株中国 CDV 临床分离株中定义表位的保守程度，发现这些 CDV 分离株中有一个氨基酸位点变异。2 株分离株存在 F451L 氨基酸突变，而 1 株存在 P448S 取代。系统进化分析显示，具有 F451L 取代的两个分离株与强毒力株 ZJ-7 的关系更为密切，因此该表位可能是与病毒毒力相关的重要标记。
本研究收集的单克隆抗体和定义的线性表位可能为 NP 蛋白功能研究和 CDV 特异性诊断试剂的开发提供有用的试剂。
