College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China.
College of Animal & Veterinary Sciences, Southwest Minzu University, Chengdu, China.
Vet Microbiol. 2022 Jul;270:109473. doi: 10.1016/j.vetmic.2022.109473. Epub 2022 May 26.
In this study, 192 diarrheal fecal samples were collected from 2019 to 2021 for monitoring the molecular prevalence of canine parvovirus 2 (CPV-2) among dogs in Southwest China, and 113 samples were detected as Carnivore protoparvovirus 1-positive. Surprisingly, 28/113 (24.8%) strains were identified as feline parvovirus (FPV)-like viruses based on the key amino acid (aa) residues in VP2. Further, 6 FPV-like strains were successfully isolated and genome sequenced, and phylogenetic trees based on the genome, VP2 and NS1 sequences showed that the 6 FPV-like strains were most genetically related with FPV instead of CPV-2. Interestingly, the VP2 proteins of the FPV-like virus contained all key aa residues typical for FPV and can be 100% identical to that of FPV, but the VP1 intron and NS1 aa sequences exhibited some unique molecular characteristics. The FPV-like isolate could hemagglutinate swine erythrocyte at pH values between 6 and 8, and replicated efficiently in MDCK cell line; moreover, the virus could cause canine systemic infection via oral administration. Further analysis based on VP2 sequences of FPV and CPV-2 in GenBank revealed that the FPV-like virus had already existed among dogs in 4 Asian countries, and have circulated widely in China. This study first confirmed that the FPV-like isolates could efficiently infect dogs, and has been prevalent among dogs in China. Moreover, this study first reported the genome characteristics of the FPV-like virus in dogs, which may represent a novel evolution pattern involving in the cross-species transmission of the virus from cats to dogs.
在这项研究中，从 2019 年到 2021 年，收集了 192 份腹泻粪便样本，用于监测中国西南地区犬细小病毒 2（CPV-2）的分子流行率，其中 113 份样本检测为 Carnivore protoparvovirus 1 阳性。令人惊讶的是，根据 VP2 中的关键氨基酸（aa）残基，28/113（24.8%）株被鉴定为猫细小病毒（FPV）样病毒。进一步地，成功分离并测序了 6 株 FPV 样病毒，基于基因组、VP2 和 NS1 序列构建的系统进化树显示，这 6 株 FPV 样病毒与 FPV 而不是 CPV-2 的亲缘关系最密切。有趣的是，FPV 样病毒的 VP2 蛋白包含所有典型的 FPV 关键 aa 残基，并且可以与 FPV 的 VP2 蛋白 100%相同，但 VP1 内含子和 NS1 aa 序列表现出一些独特的分子特征。FPV 样分离株能够在 pH 值为 6 到 8 之间凝集猪红细胞，并且在 MDCK 细胞系中高效复制；此外，该病毒可以通过口服途径引起犬全身感染。基于 GenBank 中 FPV 和 CPV-2 的 VP2 序列进一步分析表明，FPV 样病毒已经存在于亚洲 4 个国家的犬中，并在中国广泛传播。本研究首次证实 FPV 样分离株能够有效地感染犬，并在中国犬中流行。此外，本研究首次报道了犬 FPV 样病毒的基因组特征，这可能代表了一种新型的进化模式，涉及病毒从猫到犬的跨种传播。
