Veterinary microbiology最新文献

{"title":"Fusobacterium necrophorum mediates the inflammatory response in the interdigital skin and fibroblasts of dairy cows via the TNF-α/TNFR1/NF-κB pathway","authors":"Yang Yue,&nbsp;Anchi Zhang,&nbsp;Meng Liu,&nbsp;Yansong Ge,&nbsp;Enshuang Xu,&nbsp;Jiasan Zheng","doi":"10.1016/j.vetmic.2025.110483","DOIUrl":"10.1016/j.vetmic.2025.110483","url":null,"abstract":"<div><div>Foot rot is a contagious disease caused by <em>F.necrophorum</em>. It is responsible for economic losses in dairy farming. Studies on foot rot in dairy cows are focused on the isolation and identification of pathogens and treatment methods. Few studies have reported inflammatory changes in tissues and regulatory mechanisms following infection. Here, the effects of <em>F.necrophorum</em> infection on the skin explants and skin fibroblasts between the toes of cattle were analyzed using histopathology and other techniques. <em>F.necrophorum</em> infection increased the epidermal thickness and number of hair follicles and sebaceous glands. Other skin appendages exhibited varying degrees of necrosis, and a significant infiltration of inflammatory cells was noted in the interdigital skin explants. The expressions of pro-inflammatory cytokines (IL-1β and TNF-α) and key genes in the inflammatory signalling pathway (TNFR1 and NF-κB p65) were elevated. Treatment with the TNFR1 inhibitor CAY10500 reduced inflammatory cell infiltration and alleviated TNFR1 and p65 expression. An inflammatory cell model was established using different proportions of <em>F.necrophorum</em> to infect BDF cells. <em>F.necrophorum</em> infection significantly inhibited the proliferation and viability of BDF cells and enhanced the expression of TRADD, TRAF2, TNF-α, and IL-18. CAY10500 reduced the <em>F.necrophorum</em> infection–induced inflammatory response and induced inflammatory responses in interdigital skin explants and BDF cells by inhibiting the TNF-α/TNFR1/NF-κB signaling pathway. In summary, these findings provide new insights into the mechanism of inflammatory responses in dairy cows with foot rot.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"304 ","pages":"Article 110483"},"PeriodicalIF":2.4,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic characterization of Streptococcus suis serotype 31 isolated from one human and 17 clinically asymptomatic pigs in Thailand","authors":"Parichart Boueroy ,&nbsp;Nattamol Phetburom ,&nbsp;Rapeephan Duangjanchot ,&nbsp;Thidathip Wongsurawat ,&nbsp;Piroon Jenjaroenpun ,&nbsp;Peechanika Chopjitt ,&nbsp;Rujirat Hatrongjit ,&nbsp;Han Zheng ,&nbsp;Jinquan Li ,&nbsp;Anusak Kerdsin","doi":"10.1016/j.vetmic.2025.110482","DOIUrl":"10.1016/j.vetmic.2025.110482","url":null,"abstract":"<div><div><em>Streptococcus suis</em> is a zoonotic pathogen capable of causing severe diseases in humans and pigs. Frequently, <em>S. suis</em> serotype 31 strains have been isolated from pigs. The first human case of <em>S. suis</em> was reported in Thailand in 2015. In total, 18 strains from one human and 17 clinically asymptomatic pigs in Thailand were analyzed to characterize <em>S. suis</em> serotype 31. In total, 11 different STs were identified, with the major ST being ST2767 (38.89 %; 7/18). The minimum core-genome (MCG) classification revealed that almost all of the serotype 31 strains belonged to MCG7 (94.44 %; 17/18). Genomic analysis revealed that the serotype 31 isolates were major clusters with the porcine-healthy strains from China, Viet Nam, and Thailand. The human serotype 31 ST221 isolate was closely related to <em>S. suis</em> serotype 5 and 24 strains (CC221/234) isolated from Thailand. All serotype 31 strains were multidrug resistant with resistance to azithromycin (100 %; 18/18) and tetracycline (100 %; 18/18). Notably, 10 (55.56 %) of the serotype 31 strains were resistant to penicillin, while 8 strains (44.44 %) showed intermediate resistance to this agent. High substitutions were observed in three penicillin-binding proteins (1 A, 2B, and 2X) of these serotype 31 strains. The most prevalent antimicrobial resistance genes were <em>erm(B)</em> (100 %; 18/18) and <em>tet(O)</em> (66.67 %; 12/18). Overall, 7 strains carried integrative conjugative elements (ICEs) that harbored antimicrobial resistance genes, such as <em>erm(B), tet(O),</em> and <em>tet(W)</em>. This study contribute to understanding the genomic diversity and provide valuable information for public health awareness of multidrug-resistant <em>S. suis</em> serotype 31.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"304 ","pages":"Article 110482"},"PeriodicalIF":2.4,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Construction and evaluation of recombinant rabies virus encoding three copies codon-optimized G genes as inactivated rabies vaccine in dogs and cats.","authors":"Ying Wu, Haoqi Li, Zongmei Wang, Tao Pei, Qinghua Shang, Jianqing Zhao, Ming Zhou, Zhen F Fu, Chengguang Zhang, Ling Zhao","doi":"10.1016/j.vetmic.2025.110481","DOIUrl":"https://doi.org/10.1016/j.vetmic.2025.110481","url":null,"abstract":"<p><p>Rabies is a fatal zoonotic disease affecting various warm-blooded animals. The number of dogs and cats in China has surpassed 120 million, yet no domestic universal rabies vaccine for them. The glycoprotein (G) of the rabies virus (RABV) serves as the principal antigen for inducing virus-neutralizing antibodies (VNA). In this study, we constructed a recombinant RABV strain (designated SAD-tOG) carrying three copies of the codon-optimized G gene using reverse genetics. The SAD-tOG strain exhibited comparable growth kinetics to the parent strain in cell culture while demonstrating enhanced G protein expression. Mouse challenge experiments revealed significantly reduced pathogenicity and elevated immunogenicity in the recombinant strain. Subsequently, a safe and efficient water-based adjuvant was selected to prepare an inactivated rabies vaccine. In another experiment, the VNA titers of dogs and cats after vaccination were both greater than the WHO-recommended protective antibody titer of 0.5 IU/ml for 360 days. Comparative analysis showed these titers were higher than those induced by commercial vaccines currently used in China. These findings collectively indicate that the SAD-tOG strain represents a safer and more effective vaccine candidate for dog and cat rabies prevention.</p>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"304 ","pages":"110481"},"PeriodicalIF":2.4,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143671141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DNMT3B inhibits PCV2 replication via targeting TMEM37 to regulate Ca2 + influx in PK15 cells","authors":"Xiaomei Du ,&nbsp;Qi Xiao ,&nbsp;Li Yang ,&nbsp;Yiyi Shan ,&nbsp;Yueqing Hu ,&nbsp;Wenbin Bao ,&nbsp;Shenglong Wu ,&nbsp;Zhengchang Wu","doi":"10.1016/j.vetmic.2025.110480","DOIUrl":"10.1016/j.vetmic.2025.110480","url":null,"abstract":"<div><div>Porcine circovirus type 2 (PCV2) is the main pathogen causing postweaning multisystemic wasting syndrome, which leads to enormous losses for porcine industry. However, the regulatory mechanism of PCV2 replication in host cells remains not been clarified. Here, pig <em>DNMT3B</em> was identified as be a host regulator associated with PCV2 infection via RNA-seq analysis. We demonstrated that upregulation of <em>DNMT3B</em> expression can effectively inhibit PCV2 replication in PK15 cells. Besides, <em>TMEM37</em> acts as a key downstream target of <em>DNMT3B</em> in PCV2-infected PK15 cells. <em>TMEM37</em> knockdown significantly slowed Ca²⁺ influx, and thus inhibited PCV2 replication. Taken together, DNMT3B is required for the PCV2-based infection regulation in host cells. Our findings indicated that DNMT3B inhibits PCV2 replication via targeting <em>TMEM37</em> to regulate Ca²⁺ influx in PK15 cells, which offering a theoretical foundation for the use of this gene as a key biomarker for breeding strategies seeking to improve porcine disease resistance.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"304 ","pages":"Article 110480"},"PeriodicalIF":2.4,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mouse models of Tembusu virus infection for differentiating between cluster 2.1 and 2.2 isolates","authors":"Chonglun Feng,&nbsp;Qiong Li,&nbsp;Dongying Miao,&nbsp;Xiaoyang Hu,&nbsp;Jingjing Huang,&nbsp;Duo Peng,&nbsp;Yinuo Song,&nbsp;Dabing Zhang","doi":"10.1016/j.vetmic.2025.110474","DOIUrl":"10.1016/j.vetmic.2025.110474","url":null,"abstract":"<div><div>Tembusu virus (TMUV) cluster 2.1 and 2.2 strains are known to produce lethal neurological disease in mice inoculated by intracerebral (ic) route. Here, we report the comparative clinicopathological findings following experimental infections of 3-week-old BALB/c and Kunming mice with cluster 2.1 isolate H and cluster 2.2 isolate Y. When infected by the subcutaneous (sc) route, both isolates failed to induce disease in mice. When infected by the ic route, both isolates caused lethal neurological disease in mice, with isolate H presenting markedly higher neurovirulence than isolate Y. Further studies with the Kunming mouse model showed that following sc inoculation, both H and Y isolates failed to replicate in brain and spleen, and that following ic inoculation, isolate H replicated to higher levels in brain and spleen than isolate Y. The findings may help to explain non-neuroinvasive property of clusters 2.1 and 2.2 and suggest that enhanced neurovirulence of cluster 2.1 relative to cluster 2.2 is associated with more efficient replication in the central nervous system and in the periphery. Moreover, isolate H induced significantly higher levels of IFN-β, IL-1β, IL-6, TNF-α, <em>Ifit1</em>, and <em>Ifit2</em> expression relative to isolate Y, indicating a positive correlation between TMUV neurovirulence and magnitude of antiviral innate immune response. The present work demonstrates that the mouse models allow to differentiate between cluster 2.1 and 2.2 isolates and provides mechanistic insights into TMUV-induced disease.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"304 ","pages":"Article 110474"},"PeriodicalIF":2.4,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of phylogroup, sequence type, resistome and virulome in Escherichia coli resulting in feline bacterial cystitis and subclinical bacteriuria","authors":"Annelies van Bohemen ,&nbsp;Dieter Bulach ,&nbsp;Siân-Marie Frosini ,&nbsp;Thurid Johnstone ,&nbsp;Rosanne E. Jepson","doi":"10.1016/j.vetmic.2025.110477","DOIUrl":"10.1016/j.vetmic.2025.110477","url":null,"abstract":"<div><div>There is limited information on <em>E. coli</em> from feline urine and whether associated virulence and antimicrobial resistance patterns contribute to disease manifestations. This study aimed to characterise <em>E. coli</em> isolates, sequence types (ST), antimicrobial resistance (ARG) and virulence associated genes (VAG) from cats in primary care with subclinical bacteriuria (SBU) or lower urinary tract infection (LUTI).</div><div>Whole genome sequencing (WGS) was performed on <em>E. coli</em> isolates that had been stored from a longitudinal health monitoring programme. Clinical records were reviewed to determine underlying disease conditions, phenotypic susceptibility and SBU and LUTI status. Descriptive review of phylogroup and ST was assessed together with evaluation of ARG and VAG by ST and based on SBU or LUTI status.</div><div>WGS data was available for 152 <em>E. coli</em> isolates from cats (n = 26 with LUTI, n = 126 with SBU). The most common phylogroup was B2 with ST73, ST80, ST83 and ST127 predominating and ST80 being associated with clinical LUTI. Evaluating all isolates, there was no difference in prevalence of MDR status, total VAG or ARG count from cats with SBU or LUTI. Exploring individual VAG, <em>ibe</em>A, an invasin, and <em>kps</em>T, part of the group 2 polysaccharide capsule, were associated with LUTI whilst P-fimbrial genes (<em>pap</em>) were associated with SBU.</div><div>Based on this study, evidence is limited that expression of LUTI is directly related to ST or virulome and there is no evidence for increased resistome with SBU. However, low prevalence of cats with clinical LUTI may have precluded identification of associations.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"304 ","pages":"Article 110477"},"PeriodicalIF":2.4,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of cross-resistance gene optrA-carrying Campylobacter coli","authors":"Jin Kang ,&nbsp;Shuigen Wan ,&nbsp;Wenbo Zhao ,&nbsp;Shihong Li ,&nbsp;Wenjun Li ,&nbsp;Hao Li ,&nbsp;Yong Liu ,&nbsp;Hexiang Huang ,&nbsp;Chunyan Xu ,&nbsp;Xiang-Dang Du ,&nbsp;Hong Yao","doi":"10.1016/j.vetmic.2025.110476","DOIUrl":"10.1016/j.vetmic.2025.110476","url":null,"abstract":"<div><div><em>Campylobacter</em> is a significant foodborne pathogen causing human campylobacteriosis. The <em>optrA</em> gene, which encodes an ABC-F protein, confers cross-resistance to oxazolidinones and phenicols, and recent studies have identified the emergence of <em>optrA</em> in <em>Campylobacter.</em> However, detailed information of <em>optrA</em>- carrying <em>C. coli</em> from food-producing animals and various other sources globally, as analyzed by Whole Genome Sequencing (WGS), remains unknown. In this study, our objective was to explore the distribution and genotypic characteristics of <em>optrA</em>-positive <em>C. coli</em> isolates while also analyzing the genetic environment and constructing a phylogenetic tree for <em>optrA</em> using WGS data collected. Altogether, 80 <em>C. coli</em> isolates in the GenBank database along with four <em>C. coli</em> isolates from this study harboring <em>optrA</em> were obtained and used for further analyses. The results revealed that <em>optrA</em>-harboring <em>C. coli</em> were geographically distributed in China and Vietnam, deriving from food-producing animals, food and human. MLST analysis showed that 25 known STs were involved in spread of <em>optrA</em>, with ST854 being the dominant ST. Whole-genome multilocus sequence typing (Wg-MLST) analysis further illustrated a close relationship between <em>optrA</em>-positive <em>C. coli</em> isolates. Furthermore, 19 different types of genetic environments surrounding <em>optrA</em> were identified with insertion sequences IS<em>1216E</em> and IS<em>Chh1-</em>like as the mainly flanking genes, which may accelerate dissemination of <em>optrA</em>. In conclusion, this study supplies a comprehensive perspective on the distribution of the <em>optrA</em> resistance gene, elucidating its horizontal transferability and regional clonal spread patterns. The close relationship between <em>optrA</em>-positive <em>C. coli</em> isolates recovered from food-producing animals and humans emphasizes the potential for zoonotic transmission, which needs further surveillance.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"304 ","pages":"Article 110476"},"PeriodicalIF":2.4,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143628146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metaviromic and metagenomic study of the pathogens in unexplained pneumonia cases in goats","authors":"Zihan Xia,&nbsp;Gan Luo,&nbsp;Lanmu-yi Gou,&nbsp;Wentao Zhang,&nbsp;Eke-gu Ji,&nbsp;Shenglin Li,&nbsp;Taichun Gao,&nbsp;Keha-mo Abi,&nbsp;Falong Yang","doi":"10.1016/j.vetmic.2025.110469","DOIUrl":"10.1016/j.vetmic.2025.110469","url":null,"abstract":"<div><div>Goats are an economically important livestock species in China. However, the high mortality rate due to pneumonia represents a significant challenge to the development of intensive goat farms. 10 goat lung tissue samples were collected in this study, and all samples exhibited pneumonia of different severity as determined by lung lesion scoring and histopathological examination. Subsequently, this study employed qRT-PCR to measure the relative expression level of pro-inflammatory cytokines in lung tissue, and conducted metaviromic and metagenomic analyses to elucidate the structure and composition of the pulmonary microbiota, the correlation between the abundance of specific microbes and inflammatory factors, and between microbial abundance and the expression of virulence genes. Metaviromic results indicated that Ungulate tetraparvovirus 4 (83.3 %) had the highest relative abundance in the viral composition. Metagenomic data showed that <em>Mycoplasma</em> (28.2 %) and <em>Streptococcus</em> (24.8 %) are the primary dominant genus in goat pneumonia. Notably, a total of 8 pathogens associated with pneumonia in humans or animals were identified across all samples, including <em>Mycoplasma ovipneumoniae</em>, <em>Streptococcus agalactiae</em>, <em>Streptococcus pneumoniae</em>, <em>Escherichia coli, Bordetella hinzii</em>, <em>Bibersteinia trehalosi</em>, <em>Bordetella pertussis</em>, and <em>Pasteurella multocida</em>, with mixed infections with multiple pathogens are very common in this study. Correlation analysis indicates a significant association between the degree of pathogen co-infection and the severity of pulmonary lesions. Furthermore, <em>Pasteurella multocida</em> showed a significant positive correlation with the expression of IL-6 (<em>P&lt;</em> 0.01). The pneumonia samples also revealed a multitude of virulence factors associated with bacterial pathogenicity including those related to biofilm formation, endotoxin production, bacterial invasion and evasion of host immunity. In conclusion, the present study can provide a reference for clinical pathogen diagnosis of unexplained pneumonia in goats.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"304 ","pages":"Article 110469"},"PeriodicalIF":2.4,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to \"Construction with recombinant epitope-expressing baculovirus enhances protective effects of inactivated H9N2 vaccine against heterologous virus\" [Vet. Microbiol. 300 (2025) 110337].","authors":"Zimin Xie, Yingyi Chen, Jun Xie, Shanyao Du, Rongmao Chen, Yuqin Zheng, Bowen You, Min Feng, Ming Liao, Manman Dai","doi":"10.1016/j.vetmic.2025.110457","DOIUrl":"https://doi.org/10.1016/j.vetmic.2025.110457","url":null,"abstract":"","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":" ","pages":"110457"},"PeriodicalIF":2.4,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143587296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Serum amyloid P component suppresses porcine epidemic diarrhea virus replication through TLR4-mediated IFN-β signaling pathway","authors":"Xinchang Lu ,&nbsp;Huixin Zhu ,&nbsp;Mingyu Liu ,&nbsp;Yufan Xu ,&nbsp;Zhen Yang ,&nbsp;Juan Bai ,&nbsp;Ping Jiang ,&nbsp;Xianwei Wang","doi":"10.1016/j.vetmic.2025.110459","DOIUrl":"10.1016/j.vetmic.2025.110459","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 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.</div></div>","PeriodicalId":23551,"journal":{"name":"Veterinary microbiology","volume":"304 ","pages":"Article 110459"},"PeriodicalIF":2.4,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143609913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}