{"title":"Characterization of a novel, virulent PRRSV-1 subtype 1 strain with intestinal tropism in China.","authors":"Keyi Liu, Kang Zhang, Xindong Wang, Zhiying Su, Wenbo Liu, Guochang Chen, Tongwei Ren, Jianguang Qin, Jiaqi Liu, Yanli Pang, Yeshi Yin, Yifeng Qin, Kang Ouyang, Ying Chen, Weijian Huang, Yingyi Wei, Zuzhang Wei","doi":"10.1016/j.micpath.2025.107951","DOIUrl":null,"url":null,"abstract":"<p><p>Porcine reproductive and respiratory syndrome virus (PRRSV) causes abortions in sows and abnormal respiratory symptoms in piglets. Recently, reports of PRRSV-1 infection in China are growing, however, data on the pathogenicity of PRRSV-1 subtype 1 are limited. In this study, a PRRSV strain, namely GXFS20220129, was isolated from the lung tissues of piglets exhibiting respiratory distress and diarrhea on a pig farm in southern China. Phylogenetic analysis revealed that the isolate belongs to lineage S1.1 within subtype 1 PRRSV-1, and is distinct from the major epidemic strains of PRRSV-1 in China. Sequence identity analysis showed that GXFS20220129 shares 77.4 %-90.1 % similarity with various PRRSV-1 subtypes, with the highest similarity (90.1 %) to the PRRSV-1 prototype strain LV. Compared to other subtype 1 PRRSV-1 strains, GXFS20220129 has 20 amino acid deletions (positions 274-293) and 18 amino acid deletions (positions 324-341) in the Nsp2 region. Piglets infected with GXFS20220129 exhibited transient fever, coughing, diarrhea, and weight loss, ultimately resulting in the death of 2 out of 4 piglets. Quantitative real-time PCR (qRT-PCR) showed comparable viral loads in the lung and intestinal tissues of infected piglets. Histopathological analyses revealed significant interstitial pneumonia and disruption of intestinal epithelial structures. Immunohistochemical analysis confirmed the presence of PRRSV N protein in both lung and intestinal tissues. These findings indicate that the GXFS20220129 strain is virulent and has a distinct intestinal tropism, causing severe clinical manifestations and mortality in piglets.</p>","PeriodicalId":18599,"journal":{"name":"Microbial pathogenesis","volume":" ","pages":"107951"},"PeriodicalIF":3.5000,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Microbial pathogenesis","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1016/j.micpath.2025.107951","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/8/8 0:00:00","PubModel":"Epub","JCR":"Q3","JCRName":"IMMUNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) causes abortions in sows and abnormal respiratory symptoms in piglets. Recently, reports of PRRSV-1 infection in China are growing, however, data on the pathogenicity of PRRSV-1 subtype 1 are limited. In this study, a PRRSV strain, namely GXFS20220129, was isolated from the lung tissues of piglets exhibiting respiratory distress and diarrhea on a pig farm in southern China. Phylogenetic analysis revealed that the isolate belongs to lineage S1.1 within subtype 1 PRRSV-1, and is distinct from the major epidemic strains of PRRSV-1 in China. Sequence identity analysis showed that GXFS20220129 shares 77.4 %-90.1 % similarity with various PRRSV-1 subtypes, with the highest similarity (90.1 %) to the PRRSV-1 prototype strain LV. Compared to other subtype 1 PRRSV-1 strains, GXFS20220129 has 20 amino acid deletions (positions 274-293) and 18 amino acid deletions (positions 324-341) in the Nsp2 region. Piglets infected with GXFS20220129 exhibited transient fever, coughing, diarrhea, and weight loss, ultimately resulting in the death of 2 out of 4 piglets. Quantitative real-time PCR (qRT-PCR) showed comparable viral loads in the lung and intestinal tissues of infected piglets. Histopathological analyses revealed significant interstitial pneumonia and disruption of intestinal epithelial structures. Immunohistochemical analysis confirmed the presence of PRRSV N protein in both lung and intestinal tissues. These findings indicate that the GXFS20220129 strain is virulent and has a distinct intestinal tropism, causing severe clinical manifestations and mortality in piglets.
期刊介绍:
Microbial Pathogenesis publishes original contributions and reviews about the molecular and cellular mechanisms of infectious diseases. It covers microbiology, host-pathogen interaction and immunology related to infectious agents, including bacteria, fungi, viruses and protozoa. It also accepts papers in the field of clinical microbiology, with the exception of case reports.
Research Areas Include:
-Pathogenesis
-Virulence factors
-Host susceptibility or resistance
-Immune mechanisms
-Identification, cloning and sequencing of relevant genes
-Genetic studies
-Viruses, prokaryotic organisms and protozoa
-Microbiota
-Systems biology related to infectious diseases
-Targets for vaccine design (pre-clinical studies)