犬细小病毒CPV-SD03/19株的分离鉴定及遗传演化分析

Isolation, identification and phylogenetic analysis of canine parvovirus CPV-SD03/19

为了解山东地区犬细小病毒(canine parvovirus,CPV)的生物学特性,阐明其基因组与遗传演化等特征,采集疑似感染CPV死亡犬的小肠,经PCR鉴定为CPV阳性,无菌处理病料后接种F81细胞进行病毒分离鉴定,通过电镜形态学观察及理化特性、血清学、分子生物学等试验进行验证。结果:成功鉴定、分离出1株CPV,命名为CPV-SD03/19株;电镜观察病毒粒子形态符合细小病毒形态特征;血凝试验效价为2;对NS基因和VP2基因进行序列比对与遗传进化树分析,结果显示CPV-SD03/19株抗原型为CPV-2a型,与CPV-LZ1株对比,在VP2基因上共有3处氨基酸发生非同义替换,分别为aa267(苯丙氨酸→酪氨酸)、aa426(天冬酰胺→赖氨酸)、aa440(苏氨酸→丙氨酸)。本研究对分析山东地区犬细小病毒的进化特征具有一定的参考价值。

In order to understand the biological characteristics of canine parvovirus(CPV)in Shandong Province and to elucidate its genome and genetic evolution,intestinal tissue samples were collected from dogs suspected to be infected with CPV.PCR was used to identify positive CPV,and F81 cells were used to isolate the virus.,Then,morphological observation by electron microscopy,tests of physicochemical properties,serology,molecular biology as well as other experimental methods were performed or applied to identify CPV.The results showed that a CPV strain,named CPV-SD03/19,was successfully identified and isolated,of which the morphology of viral particles observed by electron microscopy and the physicochemical properties conformed to the characteristics of a parvovirus.Analysis of the genetic evolution tree of the NS and VP2 genes,and comparison with the amino acid sequence of the CPV-LZ1 strain showed that there were three amino acids having undergone nonsynonymous substitution in the VP2 gene:aa267(Phe→Tyr),aa426(Asn→Lys),and aa440(Thr→Ala).The present study provided valuable reference for identifying the evolutionary characteristics of canine parvovirus in the Shandong area.