Molecular Characterization of a Porcine Sapelovirus Strain Isolated in China

Abstract BackgroundPorcine sapelovirus (PSV) infections have been associated with a wide spectrum of symptoms ranging from asymptomatic infection to clinical signs including diarrhoea, pneumonia, reproductive disorders, and polioencephalomyelitis. Although it has a global distribution, studies on PSV in domestic have been relatively few so far which goes against for this pathogen’s research and disease prevention.MethodsIn this study, we isolated a PSV strain, SHCM2019, from the swine faecal specimens with PK-15 cells. To investigate its molecular characteristics and pathogenicity, the genomic sequence of the SHCM2019 strain was analysed, and further the clinical manifestations and pathological changes exhibited following inoculation of the neonatal piglets were observed.ResultsThe strain isolated with PK-15 cells, was identified as PSV by RT-PCR, IFA and TEM assays. Sequencing results showed that the full-length genome of the SHCM2019 strain was 7567 nucleotides including a 27-nucloetude poly (A) tail. Phylogenetic analysis demonstrated that the virus isolate belonged to PSV and was classified into the Chinese strain cluster. Virus recombination analysis indicated that there might be a recombination break point upstream of the 3D region in PSVs. Pathogenicity research demonstrated that the virus isolate could cause diarrhoea and pneumonia in piglets. ConclusionThis study presented the isolation of a recombinant PSV strain, SHCM2019, and demonstrated the isolate was pathogenic. Our results may provide a reference for future researches of the pathogenic mechanism and evolutionary characteristics of PSV.