犬细小病毒荆州株的分离鉴定及VP2基因序列分析

Isolation and identification of Jingzhou strain of canine parvovirus and analysis of VP2 gene sequence

研究旨在了解荆州地区犬细小病毒(canine parvovirus,CPV)的流行变异情况。试验对CPV进行分离鉴定,并对该毒株进行病毒滴度测定、病毒VP2基因测序鉴定及VP2基因序列分析。结果显示,成功分离到1株CPV,将其命名为CPV-JZ2020,且该分离株可使F81细胞出现明显的细胞病变。第5代病毒在F81细胞上的TCID50为105.0/mL。通过PCR扩增出1755 bp的VP2基因;将CPV-JZ2020株VP2基因(VP2-JZ1)与国内外CPV毒株VP2基因比对,核苷酸同源性为98.39%~99.83%,氨基酸同源性为97.56%~100.00%,申请GenBank登录号为MW495851。研究表明,VP2-JZ1属于CPV-2c型,是目前国内较为多见的一种基因型,但与传统疫苗株的亲缘性较低,可能是造成目前临床上出现免疫失败的原因之一。

The purpose of the study was to understand the prevalence and variation of canine parvovirus(CPV)in Jingzhou.The CPV was isolated and identified in the test,and the virus titer was determined,the virus VP2 gene was identified by sequencing,and the VP2 gene sequence was analyzed.The results showed that a CPV strain was successfully isolated,named CPV-JZ2020,and it could cause obvious cytopathic changes in F81 cells.The TCID50 of the fifth generation virus on F81 cells was 105.0/mL.The VP2 gene with the size of 1755 bp was amplified by PCR.Compared with the VP2 gene of CPV strains(VP2-JZ1)at home and abroad,the nucleotide homology was 98.39%~99.83%,and the amino acid homology was 97.56%~100.00%.The application GenBank accession number was MW495851.The study indicates that VP2-JZ1 is CPV-2c type,which is a more common genotype in China,but its genetic relationship with traditional vaccine strains is low,which may be one of the reasons for the current clinical immune failure.