华中地区犬瘟热病毒分离鉴定及其H基因遗传进化分析

Isolation and identification of canine distemper virus strain in Central China and sequence analysis of its H gene

为了解华中地区犬源CDV所属谱系、流行及遗传变异情况,本试验通过RT-PCR方法对华中地区2020年9月~2022年1月收集的418份犬源病料进行了检测,其中83份样品为CDV阳性,阳性率为19.9%。将阳性样品接种Vero细胞,并通过间接免疫荧光方法鉴定,成功获得13株CDV分离株。对13株CDV分离株H基因进行测序,并与32株CDV参考毒株进行同源性分析、遗传进化分析以及H蛋白潜在N糖基化位点预测分析。结果表明,分离到的13株野毒株与参考毒株相比,核苷酸同源性为87.1%~99.8%,氨基酸同源性为82.2%~100%;其中8株分离株在基因型上归属于Asia-1型,5株归属于America-1型;H基因抗原性预测分析表明,分离到的13株野毒株具有6~9个潜在的N糖基化位点。本研究为本土流行性CDV毒株的研究奠定了基础。

To analyze the lineage,prevalence and genetic evolutionary relationship of canine distemper virus strains in Central China,the study detected 418 canine samples by CDV RT-PCR which collected during September 2020 and January 2022,83 samples were confirmed to be positive.The rate of positive samples was 19.9%.The 13 CDV positive samples was successfully detected by indirect immunofluorescence and reverse transcription polymerase chain reaction.The sequence of 13 CDV strains were compared with other 32 typical CDV strains for amino acid homology analysis,phylogenetic analysis and H protein potential asparagine glycosylation sites analysis.The nucleotide and amino acid homologies of the 13 sequenced strains were 87.1%-99.8% and 82.2%-100% with the wild strain.All the CDV strains but five(were genotyped as America-1) were characterized as Asia-1 genotype.The result of predictive analysis of antigenicity of H gene showed that the 13 strains had 6—9 potential asparagine glycosylation sites.The study set the foundation for the study of local epidemic CDV strains.