Serum amyloid P component suppresses porcine epidemic diarrhea virus replication through TLR4-mediated IFN-β signaling pathway

IF 2.4 2区农林科学 Q3 MICROBIOLOGY

Veterinary microbiology Pub Date : 2025-03-08 DOI:10.1016/j.vetmic.2025.110459

Xinchang Lu , Huixin Zhu , Mingyu Liu , Yufan Xu , Zhen Yang , Juan Bai , Ping Jiang , Xianwei Wang

{"title":"Serum amyloid P component suppresses porcine epidemic diarrhea virus replication through TLR4-mediated IFN-β signaling pathway","authors":"Xinchang Lu , Huixin Zhu , Mingyu Liu , Yufan Xu , Zhen Yang , Juan Bai , Ping Jiang , Xianwei Wang","doi":"10.1016/j.vetmic.2025.110459","DOIUrl":null,"url":null,"abstract":"<div><div>Porcine epidemic diarrhea virus (PEDV) is a porcine enteropathogenic coronavirus that causes significant economic losses in many Asian and European countries. It is characterized by lethal watery diarrhea and high mortality rate in piglets. Serum amyloid P component (SAP), a member of acute response phase protein (APP) family, has been reported to play a crucial role in innate immune response against various microbial pathogens. However, its antiviral activities are little known. In this study, the antiviral activity of SAP during PEDV infection was investigated. In virus-infected IPEC cells, it was found that SAP expression was significantly upregulated. To study the role of SAP in PEDV replication, the expression of SAP was regulated in cells using eukaryotic expression plasmids expressing the SAP protein and sgRNA. PEDV replication was then assessed through real-time PCR, Western blotting, and TCID<sub>50</sub> assays. The result showed that PEDV replication was inhibited in cells overexpressing SAP and promoted in cells with SAP knocking out. To further investigate the mechanism by which SAP inhibits PEDV replication, Interferon Beta (IFN-β) and its related signaling pathway proteins were detected. The results demonstrated that SAP activates the promoter of (IFN-β) and IFN regulatory factor 3 (IRF3) mediated by Toll-Like Receptor 4 (TLR4) signaling. During PEDV infection, SAP enhances TLR4-mediated IFN-β signaling, leading to increased IFN-β expression, which subsequently suppresses PEDV replication. By using TBK1/IKBKE inhibitor MRT67307 in PEDV-infected cells, the antiviral activity of SAP was inhibited. This suggests that the antiviral effect of SAP may rely on the activation of the TBK1/IKBKE signaling pathway, which is critical for the induction of type I interferons and other antiviral responses. Moreover, the interaction between SAP and PEDV N protein and the functional domain of SAP were investigated. From the results of this study, it can be concluded that the interaction between SAP and PEDV N protein activates the TLR4-mediated IFN signaling pathway, thereby inhibiting PEDV replication.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"304 ","pages":"Article 110459"},"PeriodicalIF":2.4000,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Veterinary microbiology","FirstCategoryId":"97","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S037811352500094X","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MICROBIOLOGY","Score":null,"Total":0}

引用次数: 0

Abstract

Porcine epidemic diarrhea virus (PEDV) is a porcine enteropathogenic coronavirus that causes significant economic losses in many Asian and European countries. It is characterized by lethal watery diarrhea and high mortality rate in piglets. Serum amyloid P component (SAP), a member of acute response phase protein (APP) family, has been reported to play a crucial role in innate immune response against various microbial pathogens. However, its antiviral activities are little known. In this study, the antiviral activity of SAP during PEDV infection was investigated. In virus-infected IPEC cells, it was found that SAP expression was significantly upregulated. To study the role of SAP in PEDV replication, the expression of SAP was regulated in cells using eukaryotic expression plasmids expressing the SAP protein and sgRNA. PEDV replication was then assessed through real-time PCR, Western blotting, and TCID₅₀ assays. The result showed that PEDV replication was inhibited in cells overexpressing SAP and promoted in cells with SAP knocking out. To further investigate the mechanism by which SAP inhibits PEDV replication, Interferon Beta (IFN-β) and its related signaling pathway proteins were detected. The results demonstrated that SAP activates the promoter of (IFN-β) and IFN regulatory factor 3 (IRF3) mediated by Toll-Like Receptor 4 (TLR4) signaling. During PEDV infection, SAP enhances TLR4-mediated IFN-β signaling, leading to increased IFN-β expression, which subsequently suppresses PEDV replication. By using TBK1/IKBKE inhibitor MRT67307 in PEDV-infected cells, the antiviral activity of SAP was inhibited. This suggests that the antiviral effect of SAP may rely on the activation of the TBK1/IKBKE signaling pathway, which is critical for the induction of type I interferons and other antiviral responses. Moreover, the interaction between SAP and PEDV N protein and the functional domain of SAP were investigated. From the results of this study, it can be concluded that the interaction between SAP and PEDV N protein activates the TLR4-mediated IFN signaling pathway, thereby inhibiting PEDV replication.

查看原文本刊更多论文

求助全文

约1分钟内获得全文求助全文

来源期刊

Veterinary microbiology 农林科学-兽医学

CiteScore

5.90

自引率

6.10%

发文量

221

审稿时长

52 days

期刊介绍： Veterinary Microbiology is concerned with microbial (bacterial, fungal, viral) diseases of domesticated vertebrate animals (livestock, companion animals, fur-bearing animals, game, poultry, fish) that supply food, other useful products or companionship. In addition, Microbial diseases of wild animals living in captivity, or as members of the feral fauna will also be considered if the infections are of interest because of their interrelation with humans (zoonoses) and/or domestic animals. Studies of antimicrobial resistance are also included, provided that the results represent a substantial advance in knowledge. Authors are strongly encouraged to read - prior to submission - the Editorials (''Scope or cope'' and ''Scope or cope II'') published previously in the journal. The Editors reserve the right to suggest submission to another journal for those papers which they feel would be more appropriate for consideration by that journal. Original research papers of high quality and novelty on aspects of control, host response, molecular biology, pathogenesis, prevention, and treatment of microbial diseases of animals are published. Papers dealing primarily with immunology, epidemiology, molecular biology and antiviral or microbial agents will only be considered if they demonstrate a clear impact on a disease. Papers focusing solely on diagnostic techniques (such as another PCR protocol or ELISA) will not be published - focus should be on a microorganism and not on a particular technique. Papers only reporting microbial sequences, transcriptomics data, or proteomics data will not be considered unless the results represent a substantial advance in knowledge. Drug trial papers will be considered if they have general application or significance. Papers on the identification of microorganisms will also be considered, but detailed taxonomic studies do not fall within the scope of the journal. Case reports will not be published, unless they have general application or contain novel aspects. Papers of geographically limited interest, which repeat what had been established elsewhere will not be considered. The readership of the journal is global.