Journal of Virology最新文献

{"title":"Evolution of BA.2.86 to JN.1 reveals that functional changes in non-structural viral proteins are required for fitness of SARS-CoV-2.","authors":"Shuhei Tsujino, Masumi Tsuda, Naganori Nao, Kaho Okumura, Lei Wang, Yoshitaka Oda, Yume Mimura, Jingshu Li, Rina Hashimoto, Yasufumi Matsumura, Rigel Suzuki, Saori Suzuki, Kumiko Yoshimatsu, Miki Nagao, Jumpei Ito, Kazuo Takayama, Kei Sato, Keita Matsuno, Tomokazu Tamura, Shinya Tanaka, Takasuke Fukuhara","doi":"10.1128/jvi.00908-25","DOIUrl":"https://doi.org/10.1128/jvi.00908-25","url":null,"abstract":"<p><p>Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), is still circulating among humans, leading to the continuous evolution. SARS-CoV-2 Omicron JN.1 evolved from a distinct SARS-CoV-2 lineage, BA.2.86, and spread rapidly worldwide. It is unclear why BA.2.86 did not become dominant and was quickly replaced by JN.1, which possesses one amino acid substitution in the spike protein (S:L455S) and two in the non-spike proteins NSP6 and ORF7b (NSP6:R252K and ORF7b:F19L) compared to BA.2.86. Here, we utilized recombinant viruses to elucidate the impact of these mutations on the virological characteristics of JN.1. We found that the mutation in the spike attenuated viral replication, while the non-spike mutations acted synergistically to enhance replication. This suggests that the mutations in the non-spike proteins compensate for the one in the spike, improving viral fitness, as the mutations in the spike contribute to further immune evasion. Our findings suggest that functional changes in both the spike and non-spike proteins are necessary for the evolution of SARS-CoV-2, enabling evasion of adaptive immunity within the human population while sustaining replication.</p><p><strong>Importance: </strong>Because the spike protein is strongly associated with certain virological properties of SARS-CoV-2, such as immune evasion and infectivity, most previous studies on SARS-CoV-2 variants have focused on spike protein mutations. However, the non-spike proteins also contribute to infectivity, as observed throughout the evolution of Omicron subvariants. In this study, we demonstrate a \"trade-off\" strategy in SARS-CoV-2 Omicron JN.1 in which the reduced infectivity caused by spike mutation is compensated by non-spike mutations. Our results provide insight into the evolutionary scenario of the emerging virus in the human population.</p>","PeriodicalId":17583,"journal":{"name":"Journal of Virology","volume":" ","pages":"e0090825"},"PeriodicalIF":3.8,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145125028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single self-cleaving mRNA vaccine expressing multiple viral structural proteins elicits robust immune responses and protects nursing piglets against PDCoV infection.","authors":"Ruiming Yu, Yingjie Bai, Liping Zhang, Peng Zhou, Zhongwang Zhang, Jun Yang, Yanzhen Lu, Dongsheng Wang, Yousheng Peng, Dan Li, Jian He, Yonglu Wang, Quanwei Zhang, Ligang Yuan, Huichen Guo, Li Pan, Xinsheng Liu","doi":"10.1128/jvi.00849-25","DOIUrl":"10.1128/jvi.00849-25","url":null,"abstract":"<p><p>As an emerging swine enteric coronavirus, porcine deltacoronavirus (PDCoV) poses a severe threat to the global swine industry and has demonstrated potential for cross-species transmission. Therefore, the development of safe and effective vaccines is a top priority for the future prevention and control of PDCoV. In this study, we first designed and prepared an mRNA vaccine, S2P-mRNA-LNP, that expresses the full-length S2P (E855P, V856P) protein of PDCoV. Animal experiments demonstrated that S2P-mRNA-LNP induced significantly stronger humoral and cellular immune responses in mice than did an inactivated vaccine. Then, we introduced the P2A self-cleaving peptide into the S2P-mRNA-LNP design, generating SMN-mRNA-LNP, an LNP-encapsulated mRNA vaccine that allows the simultaneous expression of three major structural proteins of PDCoV (S, M, and N) from a single mRNA. The immunization of piglets demonstrated that both S2P-mRNA-LNP and SMN-mRNA-LNP induced robust humoral immune responses. Notably, SMN-mRNA-LNP conferred significantly superior active immune protection in piglets (5/5) than did S2P-mRNA-LNP (4/5). Further immunization experiments in pregnant sows showed that piglets born to SMN-mRNA-LNP-vaccinated sows acquired high levels of IgG, IgA, and neutralizing antibodies through the ingestion of colostrum, conferring complete passive protection (5/5). The protective efficacy of SMN-mRNA-LNP was markedly superior to that of the inactivated vaccine. In conclusion, these findings demonstrate that SMN-mRNA-LNP is a novel and highly efficacious candidate vaccine against PDCoV. In addition, the design strategy of single mRNA-LNP simultaneously delivering multiple viral antigens in this study provides a new idea for the development of porcine intestinal coronavirus mRNA vaccine in the future.IMPORTANCEIn this study, we designed and developed a novel mRNA vaccine, SMN-mRNA-LNP, capable of expressing the three major structural proteins (S, M, and N) of PDCoV from a single mRNA. This vaccine conferred superior active immune protection on piglets to that conferred by S2P-mRNA-LNP expressing only the S protein. Furthermore, following the immunization of pregnant sows with SMN-mRNA-LNP, their colostrum showed remarkably high IgA antibody titers reaching 1∶10^5.4, representing a 25-fold increase over that in the inactivated vaccine group. By suckling, newborn piglets acquired significantly greater passive immunity, which ultimately conferred complete protection against PDCoV challenge.</p>","PeriodicalId":17583,"journal":{"name":"Journal of Virology","volume":" ","pages":"e0084925"},"PeriodicalIF":3.8,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12455934/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144789496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expression of spike and hemagglutinin-esterase proteins is necessary to recover infectious recombinant bovine coronavirus.","authors":"Yoshiro Sugiura, Tatsuki Takahashi, Shiori Ueno, Sodbayasgalan Amarbayasgalan, Kenta Shimizu, Makoto Ujike, Tohru Suzuki, Wataru Kamitani","doi":"10.1128/jvi.01027-25","DOIUrl":"10.1128/jvi.01027-25","url":null,"abstract":"<p><p>Bovine coronavirus (BCoV) is a significant pathogen in cattle, and its virological analysis has been hampered by the difficulty in isolating and culturing field isolates with high titers. Here, we successfully generated recombinant BCoV using an infectious bacterial artificial chromosome DNA clone co-expressing the BCoV spike (S) and hemagglutinin-esterase (HE) proteins. We also investigated the role of trypsin in BCoV culture using a recombinant virus expressing the ZsGreen reporter gene (Rec-BCoV-Kakegawa-ZsGreen). We found that an optimized concentration of 2.5 µg/mL significantly enhanced viral titers, reaching 2 × 10⁴ TCID₅₀/mL. To explore the functional significance of the ORF2 protein, we engineered a recombinant virus in which the ORF2 gene was replaced with ZsGreen. While Rec-BCoV-Kakegawa-ZsGreen exhibited growth kinetics comparable to those of the parental BCoV Kakegawa strain during early infection, peak titers were lower, suggesting a possible role for the ORF2 protein in the later stages of the viral replication cycle. Additionally, we determined the role of S and HE protein expression in the recovery of recombinant BCoV from infectious DNA using the ZsGreen virus. In HE or S protein alone, the signal of the reporter protein ZsGreen in transfected cells was stronger than that of infectious DNA alone, but no infectious virus particles were recovered in subsequent steps. However, infectious viral particles were successfully produced only when both HE and S were present. This indicates that the addition of S and HE is necessary to produce recombinant BCoV, and the present method provides important insights into the replication mechanism and pathogenicity of BCoV.IMPORTANCEIn this study, we generated a recombinant BCoV (Rec-BCoV-Kakegawa-WT) using an infectious bacterial artificial chromosome DNA clone and confirmed that the HE protein enhanced viral release. We also identified that an optimal trypsin concentration (2.5 µg/mL) improves viral titers. Additionally, we developed a reporter virus with a ZsGreen insertion, suggesting that the ORF2 protein may play a role in late-stage viral replication. This study contributes to the optimization of BCoV culture conditions and advances vaccine development.</p>","PeriodicalId":17583,"journal":{"name":"Journal of Virology","volume":" ","pages":"e0102725"},"PeriodicalIF":3.8,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12456148/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144817035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ARRDC1 inhibits the replication of Semliki Forest virus by regulating the ubiquitination and degradation of viral nsP4.","authors":"Qinyu Peng, Xiaoyi Yang, Cancan Chen, Junfang He, Yingan Liang, Xiaotong Luo, Changbai Huang, Wenbi Wu, Ping Zhang, Chao Liu","doi":"10.1128/jvi.00977-25","DOIUrl":"10.1128/jvi.00977-25","url":null,"abstract":"<p><p>Alphavirus infection can result in a spectrum of clinical manifestations in the host, including fever, rash, arthritis, and even symptoms of encephalitis, thereby posing a severe threat to global public health security. In this study, we explored the role of arrestin domain-containing protein 1 (ARRDC1) in the replication of Semliki Forest virus (SFV), an important member of alphaviruses, by siRNA-based knockdown or CRISPR/Cas9-mediated knockout techniques. SFV replication levels are significantly increased by knockdown or knockout of ARRDC1 in multiple cell lines and inhibited by trans-complementation with ARRDC1. Our data further revealed that ARRDC1 affects the early RNA replication stage of SFV. The antiviral effect of ARRDC1 is dependent on its cell plasma membrane localization and ubiquitin ligase binding motif. Mechanistically, ARRDC1 binds to viral nonstructural protein 4 (nsP4) and facilitates its degradation by the ubiquitination pathway, thereby blocking the replication of SFV. In summary, this work identifies ARRDC1 as a novel restriction factor of SFV, potentially advancing the development of novel strategies against alphavirus infection.IMPORTANCESemliki Forest virus (SFV) belongs to the <i>Alphavirus</i> genus in the <i>Togaviridae</i> family and can cause a spectrum of clinical manifestations in the host, including fever, rash, arthritis, and even symptoms of encephalitis. Here, we reveal that ARRDC1 is a novel restriction factor for SFV in multiple cell lines, which relies on its cell plasma membrane localization and ubiquitin ligase binding motif. Interestingly, we further provide evidence that upon interacting with SFV nsP4, ARRDC1 mediates the degradation of nsP4 via the ubiquitination pathway, thereby inhibiting viral replication. Our study elucidates a new antiviral mechanism of ARRDC1 by mediating the ubiquitination and degradation of viral protein, which is of great significance for further understanding the pathogenesis of alphaviruses and the development of potential antiviral strategies.</p>","PeriodicalId":17583,"journal":{"name":"Journal of Virology","volume":" ","pages":"e0097725"},"PeriodicalIF":3.8,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12455954/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144873771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ibrutinib inhibits the replication of multiple poxviruses by targeting the Bruton tyrosine kinase.","authors":"Kang Niu, Xiru Wang, Qiwei Jiang, Kai Liu, Shijie Xie, Baifen Song, Wenxue Wu, Xiao Li, Chen Peng","doi":"10.1128/jvi.00517-25","DOIUrl":"10.1128/jvi.00517-25","url":null,"abstract":"<p><p>The recent surge in global monkeypox (mpox) outbreaks highlights the critical need for developing antiviral agents targeting orthopoxvirus infections. Ibrutinib, a selective Bruton tyrosine kinase (BTK) inhibitor initially approved by the FDA in 2013 for treating chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL), has emerged as a potential antiviral candidate based on a high-throughput screening for its efficacy against vaccinia virus (VACV). This study evaluated the antiviral capability of ibrutinib against VACV, mpox virus (MPXV), and lumpy skin disease virus (LSDV), demonstrating its strong antiviral activity against multiple poxviruses. <i>In vitro</i> assays confirmed that ibrutinib significantly inhibited the replication of VACV, MPXV, and LSDV across multiple cell lines. <i>In vivo</i> studies using VACV-infected BALB/c mice revealed that ibrutinib treatment extended survival, mitigated weight loss and lesion formation, and reduced viral loads in infected mice. Mechanistic investigations indicated that ibrutinib inhibited viral early and late protein synthesis as well as DNA replication. Furthermore, BTK manipulation influenced viral replication, underscoring ibrutinib's antiviral action through a cellular target. Notably, BTK phosphorylation and nuclear translocation were observed during poxvirus infection, suggesting its role in viral replication. Overall, our findings suggest that ibrutinib is a promising candidate for treating poxvirus infections and that its cellular target, BTK, contributes to poxvirus replication.IMPORTANCEPoxviruses are important zoonotic pathogens affecting human and animal health. The recent outbreak of monkeypox virus (MPXV) highlights the persistent threat posed by poxviruses to public health. In addition, lumpy skin disease virus (LSDV) causes economic impact by affecting the cattle industry. Currently, there are no effective drugs to combat LSD, which poses a major challenge to livestock health and productivity. Therefore, there is an urgent need to develop antiviral drugs against multiple poxviruses. Through high-throughput screening of antiviral drugs targeting vaccinia virus (VACV), we identified ibrutinib as a candidate antiviral drug. In our study, ibrutinib effectively inhibited the replication of MPXV, VACV, and LSDV <i>in vitro</i> and <i>in vivo</i>. Knockdown of Bruton tyrosine kinase (BTK), the cellular target of ibrutinib, significantly inhibited virus replication, while overexpression of BTK enhanced virus replication, which displays its role as a pro-viral effector. Overall, ibrutinib is a promising anti-poxvirus agent that can combat various poxviruses by targeting BTK.</p>","PeriodicalId":17583,"journal":{"name":"Journal of Virology","volume":" ","pages":"e0051725"},"PeriodicalIF":3.8,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12456143/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144959089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"T-cell receptor/CD28-targeted immunotherapeutics selectively drive naive T-cell expansion to generate functional HIV-specific responses.","authors":"April L Mueller, Sara Lamcaj, Scott Garforth, Christopher Hiner, Darien Woodley, Kitt Paraiso, Tian Mi, Simon Low, Ben Youngblood, Steven C Almo, Harris Goldstein","doi":"10.1128/jvi.00188-25","DOIUrl":"10.1128/jvi.00188-25","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Adoptive cell transfer (ACT), a promising immunotherapeutic approach, treats viral infections or cancer by &lt;i&gt;ex vivo&lt;/i&gt; expansion and infusion of antigen-specific CD8+ T cells, respectively. However, its wider use is limited by logistical challenges associated with the conventional method of using patient-derived dendritic cells (DCs) loaded with peptides for &lt;i&gt;ex vivo&lt;/i&gt; antigen-specific CD8+ T cell expansion. To overcome these limitations, we developed Immuno-STAT (IST), a dimeric protein scaffold that delivers peptide-specific T cell receptor (TCR) activation with or without CD28 costimulatory signals to expand CD8+ T cells specific for defined viral or cancer epitopes. In this proof-of-concept study, we demonstrate that anti-CD28-IST can selectively activate and expand polyfunctional cytotoxic CD8+ T cells from the naive repertoire, targeting the HIV-associated SL9 or melanoma-associated MART-1 epitopes. Naive MART-1-specific CD8+ T cells were reliably expanded by both peptide-loaded DCs and IST. In contrast, naive SL9-specific CD8+ T cells were expanded only by SL9-specific IST and not by conventional DC-based approaches, underscoring a unique ability of IST to stimulate some naive HIV-specific T cell responses. IST-derived SL9-specific CD8+ T cells exhibited potent cytotoxicity, diverse TCR clonotypes, and memory-differentiated phenotypes, marking a significant advance in generating antigen-specific T cells against HIV. The modular IST platform provides a scalable modality to stimulate naive CD8+ T cells to potentially mobilize preemptive CD8+ T cell responses against predicted immune escape variants, as well as subdominant conserved HIV epitopes to empower the development of innovative ACT, vaccine, and other immune strategies to advance treatments for HIV, other persistent viral infections, and cancer.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Importance: &lt;/strong&gt;Adoptive transfer of &lt;i&gt;ex vivo&lt;/i&gt;-expanded T cells with potent and broad anti-HIV activity may control HIV replication in people with HIV in the absence of antiretroviral therapy. To selectively activate and expand naive CD8+ cells targeting defined viral or cancer epitopes, we developed a unique protein architecture, termed Immuno-STAT, which delivers cognate peptide-specific T cell receptor (TCR) activation alone or in combination with CD28 costimulation. We demonstrated that polyfunctional cytotoxic CD8+ T cells specific for the HIV-associated SL9 or melanoma-associated MART-1 epitopes were expanded by αCD28-Immuno-STAT delivering peptide-specific TCR and CD28 signals, but not peptide-specific TCR signals alone. αCD28-Immuno-STAT-generated SL9-specific CD8+ T cells exhibited diverse TCR clonotypes, polyfunctionality, and potent SL9-specific cytotoxicity. Adoptive transfer of αCD28-Immuno-STAT-generated CD8+ T cells specific for defined HIV epitopes may provide the broad yet targeted responses specific for conserved HIV epitopes and predicted immune escape variants required to control HIV rep","PeriodicalId":17583,"journal":{"name":"Journal of Virology","volume":" ","pages":"e0018825"},"PeriodicalIF":3.8,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12456003/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144784611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Essential function of the integrator complex in Kaposi's sarcoma-associated herpesvirus lytic replication.","authors":"Amy Nguyen, Tianqi Li, Conner Traugot, Kimberly Paulsen, Tiffany S Nelson, Mingyi Xie, Zhe Ma","doi":"10.1128/jvi.00266-25","DOIUrl":"10.1128/jvi.00266-25","url":null,"abstract":"<p><p>The integrator complex (INT) is an essential regulator of RNA biogenesis across evolution. Most current findings describe INT's function in states of equilibrium, presenting a research gap in INT's role in dynamic states, such as in infections and cancers. Viruses hijack cellular RNA machinery to transcribe their genes and produce viral progeny, presenting a unique condition to investigate INT-dependent RNA regulation under perturbation. Kaposi's sarcoma-associated herpesvirus (KSHV) is an oncogenic DNA virus that causes two deadly cancers, Kaposi's sarcoma and primary effusion lymphoma. KSHV undergoes a highly regulated and robust transcription of viral genes upon lytic reactivation, providing a complex and dynamic system to investigate integrator-mediated viral/host RNA regulation. We find that integrator subunit 11 (INTS11), the enzymatic core of INT, is essential for KSHV lytic replication triggered by reactivation or primary infection. Further RNA-seq analyses revealed a dynamic and unique signature of human transcriptomes during each lytic stage, respectively. Although the knockdown of INTS11 resulted in selective upregulation and downregulation of certain human gene transcription, INTS11's loss globally repressed the KSHV transcriptome throughout KSHV lytic replication. This inhibited viral lytic gene expression, viral genome replication, and virion production. Integrator subunits 9 and 6 are also important for KSHV lytic replication. Mechanistically, ChIP-seq analysis showed that INTS11 is increasingly recruited to the KSHV genome with some unique binding patterns as the lytic cycle progresses, suggesting that KSHV hijacks INTS11 during lytic gene transcriptions. In all, our findings reveal the essential roles of the Integrator complex in KSHV lytic replication.IMPORTANCEThe integrator complex (INT) is essential for RNA metabolism and is fundamental to all organisms, but its function and regulation during viral infection are not well described. Kaposi's sarcoma-associated herpesvirus (KSHV) infection establishes lifelong infection and causes two deadly cancers; however, no vaccine is available. Using KSHV as a model, we found that integrator subunit 11 (INTS11), the enzymatic core of INT, is recruited to the KSHV genome under lytic phases and plays an essential role in facilitating global KSHV lytic mRNA transcription and viral production. This reveals the critical role of INT in viral infection, a common and inevitable event in human life.</p>","PeriodicalId":17583,"journal":{"name":"Journal of Virology","volume":" ","pages":"e0026625"},"PeriodicalIF":3.8,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12455965/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144835484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Envelope-dimer epitope 1 (EDE1) antibody (C10) treatment significantly reduces Zika virus replication in the male and female reproductive tracts.","authors":"Nathaniel J Schramm, Martina Kovarova, Shajer Manzoor, Adam S Cockrell, Rae Ann Spagnuolo, Franck Amblard, Leda Bassit, Raymond F Schinazi, Ralph S Baric, Angela Wahl, J Victor Garcia","doi":"10.1128/jvi.01147-25","DOIUrl":"10.1128/jvi.01147-25","url":null,"abstract":"<p><p>No effective therapy or vaccine exists to protect against the next Zika virus (ZIKV) outbreak. ZIKV has been detected in multiple organs of infected people, including immune-privileged sites like the brain, eyes, and reproductive tract. ZIKV replication in the reproductive tract is of high concern; ZIKV can be transmitted sexually or to the developing fetus of pregnant women, resulting in severe congenital defects. Here, we show that ZIKV-infected immunocompetent mice rapidly controlled viremia with no viral rebound following T cell depletion. In contrast, mice genetically deficient in B and T cells (immunodeficient mice) supported sustained ZIKV replication in all tissues examined. Treatment of ZIKV-infected immunodeficient mice with the novel nucleoside analog 7-deaza-7-fluoro-2'-C-methyladenosine (DFMA) significantly reduced viremia and prolonged survival, validating immunodeficient mice for efficacy studies of ZIKV prevention and therapeutic approaches. Importantly, we demonstrate that treatment of ZIKV-infected animals with a dengue virus cross-neutralizing antibody (EDE1, C10) suppressed systemic ZIKV replication, including in the brain, eye, and male and female reproductive tracts.IMPORTANCESince 2007, Zika virus (ZIKV) infections have been documented in over 80 countries and territories, resulting in two major outbreaks thus far. ZIKV has been detected in multiple organs of infected people, including immune-privileged sites like the brain, eyes, and reproductive tract. ZIKV replication in the reproductive tract is of high concern as ZIKV can be transmitted sexually or to the developing fetus of pregnant women, resulting in severe congenital defects. Currently, no effective therapy or vaccine exists to protect against the next outbreak. Here, we developed a preclinical animal model for ZIKV infection that we used to evaluate the efficacy of a dengue virus cross-neutralizing antibody for prevention/treatment of ZIKV infection. The antibody suppressed virus replication in blood and tissues, including the reproductive tract, suggesting that passive administration of ZIKV neutralizing antibodies could be used during future ZIKV outbreaks in high-risk populations to prevent ZIKV transmission.</p>","PeriodicalId":17583,"journal":{"name":"Journal of Virology","volume":" ","pages":"e0114725"},"PeriodicalIF":3.8,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12456144/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144873774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Human cytomegalovirus promotes <i>de novo</i> PC synthesis during early virus replication.","authors":"Ian Kline, Rebekah L Mokry, Yuecheng Xi, Magí Passols Manzano, Sidnie Layesa, Nowroz Sohrab Ali, Melissa A Moy, Felicia D Goodrum, John G Purdy","doi":"10.1128/jvi.00579-25","DOIUrl":"10.1128/jvi.00579-25","url":null,"abstract":"<p><p>Human cytomegalovirus (HCMV) infection reprograms metabolism, including lipid synthesis. While several metabolite-related pathways exhibit altered activity in infected cells, the alteration of lipid-related pathways by HCMV has not been examined beyond fatty acid synthesis and elongation. In this study, we addressed this lack of understanding by focusing on phosphatidylcholine (PC), a class of lipids we previously showed is increased by HCMV infection in human foreskin fibroblasts. Here, we expand upon this finding by demonstrating that HCMV infection increases the abundance of PCs in several different fibroblasts and, similarly, in endothelial and epithelial cells. Additionally, HCMV elevates PC levels regardless of the level of confluency, type of growth medium, and presence of serum. Next, we investigated if HCMV alters the activity in the three PC synthesis pathways. We demonstrate that HCMV infection promotes the activity in the <i>de novo</i> PC synthesis pathway using a ¹³C-choline isotopic tracer and liquid chromatography high-resolution tandem mass spectrometry. Infection did not alter the activity in the other two pathways. Moreover, we examined the kinetics of PC remodeling by HCMV and found that PC synthesis was promoted and the PC lipidome shifted after 24 h post-infection. Furthermore, we found that PC remodeling occurred when DNA synthesis and subsequent steps of virus replication were inhibited by phosphonoacetic acid. Overall, this work suggests that the early steps of HCMV replication promote the reprogramming of host lipid metabolism to ensure the synthesis of a lipidome necessary to support HCMV infection.IMPORTANCEHuman cytomegalovirus (HCMV) is a common herpesvirus that establishes a lifelong and persistent infection in its human host. HCMV infection in most people does not cause overt disease. However, in immunocompromised individuals, severe CMV-associated disease can lead to permanent disabilities and even death. Additionally, congenital CMV is the leading infectious cause of birth defects. Viruses have evolved to hijack host metabolic pathways to facilitate their replication cycle. In this study, we determine that HCMV promotes the activity in the <i>de novo</i> pathway of phosphatidylcholine (PC) synthesis. We demonstrate that the activity in the other PC synthesis pathways, the phosphatidylethanolamine N-methyltransferase and Lands cycles, is unaltered by HCMV infection. Moreover, we found that HCMV infection alters metabolic activity to increase the PC lipidome before 48 h post-infection. Additionally, our results suggest that immediate-early and early gene expression promotes changes in PC lipids. Together, our findings demonstrate that infection promotes the <i>de novo</i> PC pathway to increase PC lipids during the early stages of virus replication.</p>","PeriodicalId":17583,"journal":{"name":"Journal of Virology","volume":" ","pages":"e0057925"},"PeriodicalIF":3.8,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12456142/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144873811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interaction of West Nile virus NS5 with orthoflavivirus SLA RNAs and their effects on viral replication and inhibition.","authors":"Mandi A Feinberg, My T Le, Kassandra L Carpio, Ekaterina Knyazhanskaya, Alan D T Barrett, Kyung H Choi","doi":"10.1128/jvi.02023-24","DOIUrl":"10.1128/jvi.02023-24","url":null,"abstract":"<p><p>West Nile virus (WNV) is a single-stranded, positive-sense RNA virus in the <i>Orthoflavivirus</i> genus, within <i>Flaviviridae</i>. The genus encompasses numerous pathogens of public health importance, including WNV, dengue virus (DENV), Zika virus (ZIKV), and Japanese encephalitis virus (JEV). Orthoflavivirus replication depends on the presence of the stem-loop A (SLA) structure in the 5' untranslated region of the genome. The viral polymerase, NS5, interacts with the SLA and initiates synthesis of the negative-strand RNA. The sequences and secondary structures of SLA and NS5 are highly conserved across orthoflaviviruses, suggesting that the viruses utilize a similar SLA-mediated replication mechanism. Here, we determined the molecular shapes of WNV and JEV SLAs and investigated WNV NS5 interaction with orthoflavivirus SLAs. Although WNV NS5 interacts with DENV, ZIKV, and JEV SLAs in binding assays, only DENV and ZIKV SLAs could replace WNV SLA for viral replication. Next, we found that the top and side loops of SLA are important regions for WNV NS5 interaction. Consequently, when these SLA mutations were introduced into a WNV replicon, genomic replication was greatly reduced. Finally, we tested whether the WNV SLA mimic could inhibit viral replication. The addition of exogenous SLA reduces replication of both WNV replicon and infectious virus, suggesting that exogenous SLA can outcompete the viral SLA for NS5 interaction. Next-generation sequencing data indicate that the presence of exogenous SLA during infection increased the genetic diversity of WNV.IMPORTANCEWest Nile virus (WNV) causes West Nile disease in humans. Approximately 1 in 150 cases develops serious neurological complications, such as meningitis or encephalitis. Currently, no vaccines or antiviral treatments are available. WNV relies on a conserved RNA element in the genome, known as stem-loop A (SLA), to recruit viral polymerase for replication. We found that WNV polymerase can bind the SLAs of other orthoflaviviruses, including dengue virus (DENV), Zika virus (ZIKV), and Japanese encephalitis virus (JEV). However, only the DENV and ZIKV SLAs supported replication when substituted into a WNV replicon. The failure of the JEV SLA to support WNV replication suggests that efficient replication requires additional virus-specific factors beyond the polymerase-SLA interaction. We then tested whether exogenous SLA could act as an RNA decoy to compete with genomic SLA and inhibit viral replication. The addition of SLA RNA in virus-infected cells significantly reduced viral replication and infection, highlighting the therapeutic potential of viral RNA mimic against WNV.</p>","PeriodicalId":17583,"journal":{"name":"Journal of Virology","volume":" ","pages":"e0202324"},"PeriodicalIF":3.8,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12455937/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144873852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}