Isolation and genomic characterization of a Chinese NADC34‐like PRRSV isolated from Jiangsu province

Abstract

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important causative agents to swine industry, which has been epidemic more than 30 years. The emergence and recombination of new virus strains bring great challenges to the prevention and control of PRRSV. In the present study, we reported and characterized a novel PRRSV strain, designated as JS2021NADC34, which was for the first time isolated from clinical samples in Jiangsu province, China. Phylogenetic analysis demonstrated that JS2021NADC34 belonging to sublineage 1.5 of PRRSV-2 and was highly related to NADC34-like strains. Genetically, JS2021NADC34 strain had a continuous 100 aa depletion in NSP2, as compared to VR-2332 strain, which was consistent with most reported NADC34-like strains. Moreover, there were several amino acid substitutions occurred in the antigenic regions of GP2-GP5. Similar to other reported NADC34-like PRRSV in China, JS2021NADC34 had no recombination with other domestic strains, which indicates this sublineage of PRRSV may be directly transported from the United States and have not undergone extensive mutation and recombination with local strains yet.

High Pathogenicity of a Chinese NADC34-like PRRSV on Pigs

“…JS2021NADC34 strain was previously isolated from the lung samples of disease pigs and purified by plaque assay for three rounds ( 8 ). Compared to other reported Chinese NADC34-like PRRSVs, the virus could replicate in porcine alveolar macrophages (PAMs) with apparent cytopathic effect (CPE) ( Fig.…”

“…To further explore the pathogenicity of Chinese NADC34-like PRRSV, we tested the pathogenicity of JS2021NADC34 PRRSV, a Chinese NADC34-like PRRSV isolated from Jiangsu province of China in 2021 ( 8 ). Similar to IA/2014/NADC34 and HLJDZD32-1901 PRRSVs, JS2021NADC34 strain has no recombination with other PRRSVs (data not shown).…”

“…MF326985 ) and therefore was designated NADC34-like PRRSV ( 3 , 4 ). Since then, dozens of NADC34-like PRRSVs have been reported ( 5 – 8 ). In these reports, sows suffer abortion with abortion rates between 10% and 30%, and piglets have increased mortality rates ranging from 10% to 80% ( 2 ).…”

“…In contrast, another Chinese NADC34-like PRRSV was reported to have high pathogenicity to pigs ( 9 ). In our previous study, we successfully isolated an NADC34-like PRRSV, designated JS2021NADC34, from a pig farm in Jiangsu province where sows suffered increased abortions and piglets had high mortality ( 8 ). Therefore, in this study, we tested the pathogenicity of this virus on pigs by experimental infection.…”

Genome-Wide Characterization of QYYZ-Like PRRSV During 2018–2021

“…At the same time, there was one amino acid substitution in T-cell epitope 2 (I 152 ), compared to PRRSV strains in other lineages ( 42 ). We then analyzed the functional domains in GP5 of QYYZ-like strains, including the signal peptide and transmembrane (TM) domain ( 43 ). Two residues (S 25 and I 26 ) resided within the signal peptide (aa 1-31).…”