不同宿主来源犬瘟热病毒的分离及致病相关基因序列分析

The isolation and related pathogenic gene sequence analysis of canine distemper virus from different hosts

利用Vero-DST细胞从死亡犬、狐狸肺、脾内分离到4株犬瘟热病毒-CDV-TM-CC、CDV-Dog-SCh、CDV-Fox-SY、CDV-Fox-WF,在Vero-DST细胞上传5代没有细胞病变,5代细胞培养物经电镜、间接免疫荧光及PCR鉴定为阳性。与本实验室保存的CDV-Monkey-BJ进行基因测序,并对与致病相关的F蛋白、V蛋白进行分析,F蛋白分析5株毒具有6个潜在N-末端糖基化位点,与强毒株同源性在92%～99.7%,与疫苗株不高于93.3%,在F1亚基内有7个特有氨基酸位点,这可能与其对灵长类致病有关。V蛋白分析表明,其与强毒株同源性在94%～99.7%之间,而与疫苗株不高于93.3%,CDV-Monkey-BJ C272R突变使其Zn结合能力丧失。试验结果显示,所有分离株均为强毒株,不同宿主毒株序列存在差异,值得进一步研究。

A new canine distemper virus was isolated from dead canine and fox lung and spleen using Vero-DST , which was designated as strain CDV-TM-CC, CDV-Dog-SCh, CDV-Fox-SY, CDV-Fox-WF. There were no cytopathic effect on Vero-DST through five passages. The cell cultures confirmed the results from CDV- positive by electron microscopy, indirect immunofluoreseence and PCR. These genomes were sequenced, F protein has six potential N-glycosylation sites, 92.3%-99.7% homology with the virulent strain, only at most 93.3% with the vaccine strain, seven special amino acid sites are located in F1 subunit, which may be related to primate pathogenicity. The V protein analysis indicated that the homology with the virulent strain is between 93.8% and 99.1%, only at most 93.3% with the vaccine strain. The mutation of C272R made CDV-Monkey-BJ lose the ability of zinc combination.