Pub Date : 2024-07-31DOI: 10.1016/j.antiviral.2024.105975
Guofu Ye , Chengcong Chen , Yongjun Zhou , Libo Tang , Jianzhong Cai , Yiyan Huang , Jiayue Yang , Yaoting Feng , Liangxing Chen , Yuhao Wang , Yanchen Ma , Guanfeng Lin , Yingsong Wu , Xiaotao Jiang , Jinlin Hou , Yongyin Li
Background
Hepatitis B core antibody (anti-HBc) is commonly present in patients with chronic hepatitis B virus (HBV) infection and serves as a marker of humoral immunity. Herein, we aim to investigate the correlation between anti-HBc and antiviral immune response and its putative role in HBV control.
Methods
Quantitative anti-HBc and levels of anti-HBc subtypes were measured in chronic hepatitis B (CHB) patients. The effects of anti-HBc on immune cells and HBV replication were evaluated using the HBV mouse models and human hepatoma cell lines.
Results
Baseline levels of IgG1 and IgG3 anti-HBc were elevated in CHB patients with favorable treatment response, and correlated with the virological response observed at week 52. Additionally, increased levels of IgM and IgG1 anti-HBc were observed exclusively in CHB patients with liver inflammation. Notably, significant correlations were identified between quantitative levels of anti-HBc and the frequencies of HBcAg-specific CD8+ T cells. Intriguingly, HBcAg efficiently activates T cells aided by B cells in vitro experiments. Moreover, anti-HBc inhibits HBV replication either by a direct effect or through complement-mediated cytotoxicity in HBV-producing cell lines.
Conclusions
Anti-HBc reflects the activation of an HBV-specific CD8+ T cell immune response and may have anti-HBV activity.
{"title":"Anti-HBc mirrors the activation of HBV-specific CD8+ T cell immune response and exhibits a direct effect on HBV control","authors":"Guofu Ye , Chengcong Chen , Yongjun Zhou , Libo Tang , Jianzhong Cai , Yiyan Huang , Jiayue Yang , Yaoting Feng , Liangxing Chen , Yuhao Wang , Yanchen Ma , Guanfeng Lin , Yingsong Wu , Xiaotao Jiang , Jinlin Hou , Yongyin Li","doi":"10.1016/j.antiviral.2024.105975","DOIUrl":"10.1016/j.antiviral.2024.105975","url":null,"abstract":"<div><h3>Background</h3><p>Hepatitis B core antibody (anti-HBc) is commonly present in patients with chronic hepatitis B virus (HBV) infection and serves as a marker of humoral immunity. Herein, we aim to investigate the correlation between anti-HBc and antiviral immune response and its putative role in HBV control.</p></div><div><h3>Methods</h3><p>Quantitative anti-HBc and levels of anti-HBc subtypes were measured in chronic hepatitis B (CHB) patients. The effects of anti-HBc on immune cells and HBV replication were evaluated using the HBV mouse models and human hepatoma cell lines.</p></div><div><h3>Results</h3><p>Baseline levels of IgG1 and IgG3 anti-HBc were elevated in CHB patients with favorable treatment response, and correlated with the virological response observed at week 52. Additionally, increased levels of IgM and IgG1 anti-HBc were observed exclusively in CHB patients with liver inflammation. Notably, significant correlations were identified between quantitative levels of anti-HBc and the frequencies of HBcAg-specific CD8<sup>+</sup> T cells. Intriguingly, HBcAg efficiently activates T cells aided by B cells <em>in vitro</em> experiments. Moreover, anti-HBc inhibits HBV replication either by a direct effect or through complement-mediated cytotoxicity in HBV-producing cell lines.</p></div><div><h3>Conclusions</h3><p>Anti-HBc reflects the activation of an HBV-specific CD8<sup>+</sup> T cell immune response and may have anti-HBV activity.</p></div>","PeriodicalId":8259,"journal":{"name":"Antiviral research","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141874045","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}
Pub Date : 2024-07-31DOI: 10.1016/j.antiviral.2024.105977
Kei Konishi , Shinji Kusakabe , Nijiho Kawaguchi , Takao Shishido , Naoto Ito , Michiko Harada , Satoshi Inoue , Ken Maeda , William W. Hall , Yasuko Orba , Hirofumi Sawa , Michihito Sasaki , Akihiko Sato
Rabies is a fatal neurological disorder caused by rabies virus (RABV) infection. Approximately 60,000 patients die from rabies annually, and there are no effective treatments for this disease. Nucleoside analogs are employed as antiviral drugs based on their broad antiviral spectrum, and certain nucleoside analogs have been reported to exhibit anti-RABV activity. The nucleoside analog β-d-N4-hydroxycytidine (NHC) has antiviral effects against a range of RNA viruses. Molnupiravir (MPV), a prodrug of NHC, is clinically used as an oral antiviral drug for coronavirus infections. Despite its broad-spectrum activity, the antiviral activity of NHC against RABV remains unclear. In this study, we reveal that NHC exhibits comparable in vitro anti-RABV activity as ribavirin and favipiravir (also known as T-705) with a 90% effective concentration of 6 μM in mouse neuroblastoma cells. NHC reduced viral loads in neuronal and nonneuronal cells in a dose-dependent manner. Both laboratory and field RABVs (fixed and street strains, respectively) were susceptible to NHC. However, no increase in survival or reduction in viral titers in the brain was observed in RABV-infected mice treated prophylactically with MPV. These findings highlight the potential and challenges of NHC in the treatment of RABV infection.
{"title":"β-d-N4-hydroxycytidine, a metabolite of molnupiravir, exhibits in vitro antiviral activity against rabies virus","authors":"Kei Konishi , Shinji Kusakabe , Nijiho Kawaguchi , Takao Shishido , Naoto Ito , Michiko Harada , Satoshi Inoue , Ken Maeda , William W. Hall , Yasuko Orba , Hirofumi Sawa , Michihito Sasaki , Akihiko Sato","doi":"10.1016/j.antiviral.2024.105977","DOIUrl":"10.1016/j.antiviral.2024.105977","url":null,"abstract":"<div><p>Rabies is a fatal neurological disorder caused by rabies virus (RABV) infection. Approximately 60,000 patients die from rabies annually, and there are no effective treatments for this disease. Nucleoside analogs are employed as antiviral drugs based on their broad antiviral spectrum, and certain nucleoside analogs have been reported to exhibit anti-RABV activity. The nucleoside analog β-<span>d</span>-<em>N</em><sup>4</sup>-hydroxycytidine (NHC) has antiviral effects against a range of RNA viruses. Molnupiravir (MPV), a prodrug of NHC, is clinically used as an oral antiviral drug for coronavirus infections. Despite its broad-spectrum activity, the antiviral activity of NHC against RABV remains unclear. In this study, we reveal that NHC exhibits comparable <em>in vitro</em> anti-RABV activity as ribavirin and favipiravir (also known as T-705) with a 90% effective concentration of 6 μM in mouse neuroblastoma cells. NHC reduced viral loads in neuronal and nonneuronal cells in a dose-dependent manner. Both laboratory and field RABVs (fixed and street strains, respectively) were susceptible to NHC. However, no increase in survival or reduction in viral titers in the brain was observed in RABV-infected mice treated prophylactically with MPV. These findings highlight the potential and challenges of NHC in the treatment of RABV infection.</p></div>","PeriodicalId":8259,"journal":{"name":"Antiviral research","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141874046","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}
Pub Date : 2024-07-31DOI: 10.1016/j.antiviral.2024.105974
Entao Li , Qizan Gong , Jiachen Zhang , Xiaoping Guo , Wenyu Xie , Da Chen , Yanqiong Shen , Dongxiang Hong , Zhihao Li , Qianqian Wang , Chao Wang , Yucai Wang , Sandra Chiu
The outbreak of 2022 monkeypox virus (MPXV) infection in nonendemic regions is a global public health concern. A highly effective and safe MPXV vaccine that is available to the general public is urgently needed to control the mpox pandemic. Here, we developed a multivalent mRNA vaccine candidate, MPXV-1103, which expresses the full-length B6, A35, A29 and M1 proteins with three flexible linkers (G4S1)3 in a single sequence. Compared with the monovalent MPXV mRNA vaccine candidates or the quadrivalent mRNA vaccine from mixtures of the four monovalent MPXV mRNA vaccines, MPXV-1103 elicits a robust humoral response and an MPXV-specific T-cell response and protects mice from lethal vaccinia virus (VACV) challenge, with no live virus detected in the nasal or lungs even at dosages as low as 1 μg. Furthermore, analysis of complete blood counts and photomicrographs of tissue from the main organs of mice vaccinated with MPXV-1103 at doses of 5 μg and 20 μg revealed that two doses of MPXV-1103 did not cause any observable pathological changes in the mice. Collectively, our results suggest that MPXV-1103, with features of high efficacy, safety and a simplified manufacturing process, is a promising vaccine candidate for defending against MPXV infection.
{"title":"An mpox quadrivalent mRNA vaccine protects mice from lethal vaccinia virus challenge","authors":"Entao Li , Qizan Gong , Jiachen Zhang , Xiaoping Guo , Wenyu Xie , Da Chen , Yanqiong Shen , Dongxiang Hong , Zhihao Li , Qianqian Wang , Chao Wang , Yucai Wang , Sandra Chiu","doi":"10.1016/j.antiviral.2024.105974","DOIUrl":"10.1016/j.antiviral.2024.105974","url":null,"abstract":"<div><p>The outbreak of 2022 monkeypox virus (MPXV) infection in nonendemic regions is a global public health concern. A highly effective and safe MPXV vaccine that is available to the general public is urgently needed to control the mpox pandemic. Here, we developed a multivalent mRNA vaccine candidate, MPXV-1103, which expresses the full-length B6, A35, A29 and M1 proteins with three flexible linkers (G<sub>4</sub>S<sub>1</sub>)<sub>3</sub> in a single sequence. Compared with the monovalent MPXV mRNA vaccine candidates or the quadrivalent mRNA vaccine from mixtures of the four monovalent MPXV mRNA vaccines, MPXV-1103 elicits a robust humoral response and an MPXV-specific T-cell response and protects mice from lethal vaccinia virus (VACV) challenge, with no live virus detected in the nasal or lungs even at dosages as low as 1 μg. Furthermore, analysis of complete blood counts and photomicrographs of tissue from the main organs of mice vaccinated with MPXV-1103 at doses of 5 μg and 20 μg revealed that two doses of MPXV-1103 did not cause any observable pathological changes in the mice. Collectively, our results suggest that MPXV-1103, with features of high efficacy, safety and a simplified manufacturing process, is a promising vaccine candidate for defending against MPXV infection.</p></div>","PeriodicalId":8259,"journal":{"name":"Antiviral research","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0166354224001839/pdfft?md5=90da3a5580e4b41adbce16a24d727952&pid=1-s2.0-S0166354224001839-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141874044","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}
Pub Date : 2024-07-30DOI: 10.1016/j.antiviral.2024.105972
Zhe Xie , Ulrike Protzer
Bispecific antibodies (bsAbs) are engineered immunoglobulins that combine two different antigen-binding sites in one molecule. BsAbs can be divided into two molecular formats: IgG-like and non-IgG-like antibodies. Structural elements of each format have implications for engaging the immune system. T cell engager antibodies (TCEs) are bsAbs designed to engage T cells with target cells. TCEs can be applied not only in cancer but also in infectious disease therapy to activate T-cell responses. In this review, we focus on current literature on the design and use of bsAbs as an innovative strategy to enhance adaptive antiviral immune responses. We summarized the novel T cell-related immunotherapies with a focus on TCEs, that are developed for the treatment of chronic hepatitis B. Chronic infection with the hepatitis B virus (HBV) had a death toll of 1.1 million humans in 2022, mainly due to liver cirrhosis and hepatocellular carcinoma developing in the more than 250 million humans chronically infected. A curative treatment approach for chronic hepatitis B is lacking. Combining antiviral therapy with immune therapies activating T-cell responses is regarded as the most promising therapeutic approach to curing HBV and preventing the sequelae of chronic infection. Attracting functionally intact T cells that are not HBV-specific and, therefore, have not yet been exposed to regulatory mechanisms and activating those at the target site in the liver is a very interesting therapeutic approach that could be achieved by TCEs. Thus, TCEs redirecting T cells toward HBV-positive cells represent a promising strategy for treating chronic hepatitis B and HBV-associated hepatocellular carcinoma.
双特异性抗体(bsAbs)是在一个分子中结合了两个不同抗原结合位点的工程免疫球蛋白。双特异性抗体可分为两种分子形式:IgG 样抗体和非 IgG 样抗体。每种形式的结构元素都会影响免疫系统的参与。T 细胞吸引抗体(TCEs)是专为吸引 T 细胞与靶细胞而设计的 bsAbs。TCEs 不仅可用于癌症治疗,还可用于传染病治疗,以激活 T 细胞反应。在这篇综述中,我们重点讨论了目前有关设计和使用 bsAbs 作为增强适应性抗病毒免疫反应的创新策略的文献。2022 年,慢性乙型肝炎病毒(HBV)感染造成的死亡人数达 110 万,主要原因是超过 2.5 亿慢性感染者出现肝硬化和肝细胞癌。目前还缺乏治疗慢性乙型肝炎的方法。将抗病毒疗法与激活 T 细胞反应的免疫疗法相结合,被认为是治愈 HBV 和预防慢性感染后遗症的最有希望的治疗方法。吸引功能完好的非 HBV 特异性 T 细胞,并在肝脏靶点激活这些细胞,是一种非常有趣的治疗方法,TCEs 可以实现这一目标。因此,将 T 细胞重新定向到 HBV 阳性细胞的 TCE 是治疗慢性乙型肝炎和 HBV 相关肝细胞癌的一种很有前景的策略。
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Pub Date : 2024-07-27DOI: 10.1016/j.antiviral.2024.105971
Li He , Laura Hertel , Claire D. James , Iain M. Morgan , Aloysius J. Klingelhutz , Tong-Ming Fu , Lawrence M. Kauvar , Michael A. McVoy
Human cytomegalovirus (CMV) causes serious developmental disabilities in newborns infected in utero following oral acquisition by the mother. Thus, neutralizing antibodies in maternal saliva have potential to prevent maternal infection and, consequently, fetal transmission and disease. Based on standard cell culture models, CMV entry mediators (and hence neutralizing targets) are cell type-dependent: entry into fibroblasts requires glycoprotein B (gB) and a trimeric complex (TC) of glycoproteins H, L, and O, whereas endothelial and epithelial cell entry additionally requires a pentameric complex (PC) of glycoproteins H and L with UL128, UL130, and UL131A. However, as the mediators of mucosal cell entry and the potential impact of cellular differentiation remained unclear, the present studies utilized mutant viruses, neutralizing antibodies, and soluble TC-receptor to determine the entry mediators required for infection of mucocutaneus cell lines and primary tonsil epithelial cells. Entry into undifferentiated cells was largely PC-dependent, but PC-independent entry could be induced by differentiation. TC-independent entry was also observed and varied by cell line and differentiation. Infection of primary tonsil cells from some donors was entirely TC-independent. In contrast, an antibody to gB or disruption of virion attachment using heparin blocked entry into all cells. These findings indicate that CMV entry into the spectrum of cell types encountered in vivo is likely to be more complex than has been suggested by standard cell culture models and may be influenced by the relative abundance of virion envelope glycoprotein complexes as well as by cell type, tissue of origin, and state of differentiation.
人类巨细胞病毒(CMV)会导致宫内感染的新生儿在母亲经口感染后出现严重的发育障碍。因此,母体唾液中的中和抗体有可能预防母体感染,进而预防胎儿传播和疾病。根据标准的细胞培养模型,CMV 的进入介质(以及中和目标)是细胞类型依赖性的:进入成纤维细胞需要糖蛋白 B(gB)和由糖蛋白 H、L 和 O 组成的三聚体复合物(TC),而进入内皮细胞和上皮细胞则需要由糖蛋白 H 和 L 与 UL128、UL130 和 UL131A 组成的五聚体复合物(PC)。然而,由于粘膜细胞进入的介质和细胞分化的潜在影响仍不清楚,本研究利用突变病毒、中和抗体和可溶性 TC 受体来确定感染粘膜细胞系和原发性扁桃体上皮细胞所需的进入介质。进入未分化细胞主要依赖 PC,但分化可诱导 PC 依赖性进入。此外,还观察到依赖于 TC 的进入,并因细胞系和分化情况而异。一些供体的原代扁桃体细胞感染完全不依赖于 TC。相反,gB 抗体或使用肝素破坏病毒附着会阻止病毒进入所有细胞。这些研究结果表明,CMV 进入体内各种细胞可能比标准细胞培养模型所显示的更为复杂,可能受到病毒包膜糖蛋白复合物的相对丰度以及细胞类型、来源组织和分化状态的影响。
{"title":"Inhibition of human cytomegalovirus entry into mucosal epithelial cells","authors":"Li He , Laura Hertel , Claire D. James , Iain M. Morgan , Aloysius J. Klingelhutz , Tong-Ming Fu , Lawrence M. Kauvar , Michael A. McVoy","doi":"10.1016/j.antiviral.2024.105971","DOIUrl":"10.1016/j.antiviral.2024.105971","url":null,"abstract":"<div><p>Human cytomegalovirus (CMV) causes serious developmental disabilities in newborns infected <em>in utero</em> following oral acquisition by the mother. Thus, neutralizing antibodies in maternal saliva have potential to prevent maternal infection and, consequently, fetal transmission and disease. Based on standard cell culture models, CMV entry mediators (and hence neutralizing targets) are cell type-dependent: entry into fibroblasts requires glycoprotein B (gB) and a trimeric complex (TC) of glycoproteins H, L, and O, whereas endothelial and epithelial cell entry additionally requires a pentameric complex (PC) of glycoproteins H and L with UL128, UL130, and UL131A. However, as the mediators of mucosal cell entry and the potential impact of cellular differentiation remained unclear, the present studies utilized mutant viruses, neutralizing antibodies, and soluble TC-receptor to determine the entry mediators required for infection of mucocutaneus cell lines and primary tonsil epithelial cells. Entry into undifferentiated cells was largely PC-dependent, but PC-independent entry could be induced by differentiation. TC-independent entry was also observed and varied by cell line and differentiation. Infection of primary tonsil cells from some donors was entirely TC-independent. In contrast, an antibody to gB or disruption of virion attachment using heparin blocked entry into all cells. These findings indicate that CMV entry into the spectrum of cell types encountered <em>in vivo</em> is likely to be more complex than has been suggested by standard cell culture models and may be influenced by the relative abundance of virion envelope glycoprotein complexes as well as by cell type, tissue of origin, and state of differentiation.</p></div>","PeriodicalId":8259,"journal":{"name":"Antiviral research","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141791774","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}
Pub Date : 2024-07-25DOI: 10.1016/j.antiviral.2024.105970
Romel Rosales , Briana L. McGovern , M. Luis Rodriguez , Rocio Leiva-Rebollo , Randy Diaz-Tapia , Jared Benjamin , Devendra K. Rai , Rhonda D. Cardin , Annaliesa S. Anderson , Emilia Mia Sordillo , Harm van Bakel , Viviana Simon , Adolfo García-Sastre , Kris M. White
Variants of SARS-CoV-2 pose significant challenges in public health due to their increased transmissibility and ability to evade natural immunity, vaccine protection, and monoclonal antibody therapeutics. The emergence of the highly transmissible Omicron variant and subsequent subvariants, characterized by an extensive array of over 32 mutations within the spike protein, intensifies concerns regarding vaccine evasion. In response, multiple antiviral therapeutics have received FDA emergency use approval, targeting the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) and main protease (Mpro) regions, known to have relatively fewer mutations across novel variants. In this study, we evaluated the efficacy of nirmatrelvir (PF-07321332) and other clinically significant SARS-CoV-2 antivirals against a diverse panel of SARS-CoV-2 variants, encompassing the newly identified Omicron subvariants XBB1.5 and JN.1, using live-virus antiviral assays. Our findings demonstrate that while the last Omicron subvariants exhibited heightened pathogenicity in our animal model, nirmatrelvir and other clinically relevant antivirals consistently maintained their efficacy against all tested variants, including the XBB1.5 subvariant.
{"title":"Nirmatrelvir and molnupiravir maintain potent in vitro and in vivo antiviral activity against circulating SARS-CoV-2 omicron subvariants","authors":"Romel Rosales , Briana L. McGovern , M. Luis Rodriguez , Rocio Leiva-Rebollo , Randy Diaz-Tapia , Jared Benjamin , Devendra K. Rai , Rhonda D. Cardin , Annaliesa S. Anderson , Emilia Mia Sordillo , Harm van Bakel , Viviana Simon , Adolfo García-Sastre , Kris M. White","doi":"10.1016/j.antiviral.2024.105970","DOIUrl":"10.1016/j.antiviral.2024.105970","url":null,"abstract":"<div><p>Variants of SARS-CoV-2 pose significant challenges in public health due to their increased transmissibility and ability to evade natural immunity, vaccine protection, and monoclonal antibody therapeutics. The emergence of the highly transmissible Omicron variant and subsequent subvariants, characterized by an extensive array of over 32 mutations within the spike protein, intensifies concerns regarding vaccine evasion. In response, multiple antiviral therapeutics have received FDA emergency use approval, targeting the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) and main protease (Mpro) regions, known to have relatively fewer mutations across novel variants. In this study, we evaluated the efficacy of nirmatrelvir (PF-07321332) and other clinically significant SARS-CoV-2 antivirals against a diverse panel of SARS-CoV-2 variants, encompassing the newly identified Omicron subvariants XBB1.5 and JN.1, using live-virus antiviral assays. Our findings demonstrate that while the last Omicron subvariants exhibited heightened pathogenicity in our animal model, nirmatrelvir and other clinically relevant antivirals consistently maintained their efficacy against all tested variants, including the XBB1.5 subvariant.</p></div>","PeriodicalId":8259,"journal":{"name":"Antiviral research","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141787142","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}
Pub Date : 2024-07-23DOI: 10.1016/j.antiviral.2024.105969
Stefanie Rauch , Francesco Costacurta , Helge Schöppe , Ju-Yi Peng , David Bante , Ela Emilie Erisoez , Bernhard Sprenger , Xi He , Seyed Arad Moghadasi , Laura Krismer , Anna Sauerwein , Anne Heberle , Toni Rabensteiner , Dai Wang , Andreas Naschberger , Theresia Dunzendorfer-Matt , Teresa Kaserer , Dorothee von Laer , Emmanuel Heilmann
In the SARS-CoV-2 pandemic, the so far two most effective approved antivirals are the protease inhibitors nirmatrelvir, in combination with ritonavir (Paxlovid) and ensitrelvir (Xocova). However, antivirals and indeed all antimicrobial drugs are sooner or later challenged by resistance mutations. Studying such mutations is essential for treatment decisions and pandemic preparedness. At the same time, generating resistant viruses to assess mutants is controversial, especially with pathogens of pandemic potential like SARS-CoV-2. To circumvent gain-of-function research with non-attenuated SARS-CoV-2, a previously developed safe system based on a chimeric vesicular stomatitis virus dependent on the SARS-CoV-2 main protease (VSV-Mpro) was used to select mutations against ensitrelvir. Ensitrelvir is clinically especially relevant due to its single-substance formulation, avoiding drug-drug interactions by the co-formulated CYP3A4 inhibitor ritonavir in Paxlovid. By treating VSV-Mpro with ensitrelvir, highly-specific resistant mutants against this inhibitor were selected, while being still fully or largely susceptible to nirmatrelvir. We then confirmed several ensitrelvir-specific mutants in gold standard enzymatic assays and SARS-CoV-2 replicons. These findings indicate that the two inhibitors can have distinct viral resistance profiles, which could determine treatment decisions.
{"title":"Highly specific SARS-CoV-2 main protease (Mpro) mutations against the clinical antiviral ensitrelvir selected in a safe, VSV-based system","authors":"Stefanie Rauch , Francesco Costacurta , Helge Schöppe , Ju-Yi Peng , David Bante , Ela Emilie Erisoez , Bernhard Sprenger , Xi He , Seyed Arad Moghadasi , Laura Krismer , Anna Sauerwein , Anne Heberle , Toni Rabensteiner , Dai Wang , Andreas Naschberger , Theresia Dunzendorfer-Matt , Teresa Kaserer , Dorothee von Laer , Emmanuel Heilmann","doi":"10.1016/j.antiviral.2024.105969","DOIUrl":"10.1016/j.antiviral.2024.105969","url":null,"abstract":"<div><p>In the SARS-CoV-2 pandemic, the so far two most effective approved antivirals are the protease inhibitors nirmatrelvir, in combination with ritonavir (Paxlovid) and ensitrelvir (Xocova). However, antivirals and indeed all antimicrobial drugs are sooner or later challenged by resistance mutations. Studying such mutations is essential for treatment decisions and pandemic preparedness. At the same time, generating resistant viruses to assess mutants is controversial, especially with pathogens of pandemic potential like SARS-CoV-2. To circumvent gain-of-function research with non-attenuated SARS-CoV-2, a previously developed safe system based on a chimeric vesicular stomatitis virus dependent on the SARS-CoV-2 main protease (VSV-M<sup>pro</sup>) was used to select mutations against ensitrelvir. Ensitrelvir is clinically especially relevant due to its single-substance formulation, avoiding drug-drug interactions by the co-formulated CYP3A4 inhibitor ritonavir in Paxlovid. By treating VSV-M<sup>pro</sup> with ensitrelvir, highly-specific resistant mutants against this inhibitor were selected, while being still fully or largely susceptible to nirmatrelvir. We then confirmed several ensitrelvir-specific mutants in gold standard enzymatic assays and SARS-CoV-2 replicons. These findings indicate that the two inhibitors can have distinct viral resistance profiles, which could determine treatment decisions.</p></div>","PeriodicalId":8259,"journal":{"name":"Antiviral research","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0166354224001785/pdfft?md5=a8eb9488aa96706381e7d5e8ab142db9&pid=1-s2.0-S0166354224001785-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141756803","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}
Pub Date : 2024-07-14DOI: 10.1016/j.antiviral.2024.105968
Ernna H. Oliveira , Ana C. Monteleone-Cassiano , Lucas Tavares , Jadson C. Santos , Thais M. Lima , Giovanni F. Gomes , Pedro P. Tanaka , Cintia J. Monteiro , Matheus Munuera , Sabrina S. Batah , Alexandre T. Fabro , Vitor M. Faça , Ana P. Masson , Eduardo A. Donadi , Mariangela Dametto , Rodrigo Bonacin , Ronaldo B. Martins Jr. , Eurico Arruda Neto , Luis Lamberti P. daSilva , Thiago M. Cunha , Geraldo A. Passos
Since human angiotensin-converting enzyme 2 (ACE2) serves as a primary receptor for SARS-CoV-2, characterizing ACE2 regions that allow SARS-CoV-2 to enter human cells is essential for designing peptide-based antiviral blockers and elucidating the pathogenesis of the virus. We identified and synthesized a 25-mer mimetic peptide (encompassing positions 22–46 of the ACE2 alpha-helix α1) implicated in the S1 receptor-binding domain (RBD)-ACE2 interface. The mimetic (wild-type, WT) ACE2 peptide significantly inhibited SARS-CoV-2 infection of human pulmonary Calu-3 cells in vitro. In silico protein modeling predicted that residues F28, K31, F32, F40, and Y41 of the ACE2 alpha-helix α1 are critical for the original, Delta, and Omicron strains of SARS-CoV-2 to establish the Spike RBD-ACE2 interface. Substituting these residues with alanine (A) or aspartic acid (D) abrogated the antiviral protective effect of the peptides, indicating that these positions are critical for viral entry into pulmonary cells. WT ACE2 peptide, but not the A or D mutated peptides, exhibited significant interaction with the SARS-CoV-2 S1 RBD, as shown through molecular dynamics simulations. Through identifying the critical amino acid residues of the ACE2 alpha-helix α1, which is necessary for the Spike RBD-ACE2 interface and mobilized during the in vitro viral infection of cells, we demonstrated that the WT ACE2 peptide protects susceptible K18-hACE2 mice against in vivo SARS-CoV-2 infection and is effective for the treatment of COVID-19.
{"title":"A mimetic peptide of ACE2 protects against SARS-CoV-2 infection and decreases pulmonary inflammation related to COVID-19","authors":"Ernna H. Oliveira , Ana C. Monteleone-Cassiano , Lucas Tavares , Jadson C. Santos , Thais M. Lima , Giovanni F. Gomes , Pedro P. Tanaka , Cintia J. Monteiro , Matheus Munuera , Sabrina S. Batah , Alexandre T. Fabro , Vitor M. Faça , Ana P. Masson , Eduardo A. Donadi , Mariangela Dametto , Rodrigo Bonacin , Ronaldo B. Martins Jr. , Eurico Arruda Neto , Luis Lamberti P. daSilva , Thiago M. Cunha , Geraldo A. Passos","doi":"10.1016/j.antiviral.2024.105968","DOIUrl":"10.1016/j.antiviral.2024.105968","url":null,"abstract":"<div><p>Since human angiotensin-converting enzyme 2 (ACE2) serves as a primary receptor for SARS-CoV-2, characterizing ACE2 regions that allow SARS-CoV-2 to enter human cells is essential for designing peptide-based antiviral blockers and elucidating the pathogenesis of the virus. We identified and synthesized a 25-mer mimetic peptide (encompassing positions 22–46 of the ACE2 alpha-helix α1) implicated in the S1 receptor-binding domain (RBD)-ACE2 interface. The mimetic (wild-type, WT) ACE2 peptide significantly inhibited SARS-CoV-2 infection of human pulmonary Calu-3 cells <em>in vitro</em>. In silico protein modeling predicted that residues F28, K31, F32, F40, and Y41 of the ACE2 alpha-helix α1 are critical for the original, Delta, and Omicron strains of SARS-CoV-2 to establish the Spike RBD-ACE2 interface. Substituting these residues with alanine (A) or aspartic acid (D) abrogated the antiviral protective effect of the peptides, indicating that these positions are critical for viral entry into pulmonary cells. WT ACE2 peptide, but not the A or D mutated peptides, exhibited significant interaction with the SARS-CoV-2 S<sup>1</sup> RBD, as shown through molecular dynamics simulations. Through identifying the critical amino acid residues of the ACE2 alpha-helix α1, which is necessary for the Spike RBD-ACE2 interface and mobilized during the <em>in vitro</em> viral infection of cells, we demonstrated that the WT ACE2 peptide protects susceptible K18-hACE2 mice against <em>in vivo</em> SARS-CoV-2 infection and is effective for the treatment of COVID-19.</p></div>","PeriodicalId":8259,"journal":{"name":"Antiviral research","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141615833","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}
Pub Date : 2024-07-13DOI: 10.1016/j.antiviral.2024.105961
Dongdong Chen , Wen Su , Ka-Tim Choy , Yan Sing Chu , Chi Ho Lin , Hui-Ling Yen
Baloxavir acid (BXA) is a pan-influenza antiviral that targets the cap-dependent endonuclease of the polymerase acidic (PA) protein required for viral mRNA synthesis. To gain a comprehensive understanding on the molecular changes associated with reduced susceptibility to BXA and their fitness profile, we performed a deep mutational scanning at the PA endonuclease domain of an A (H1N1)pdm09 virus. The recombinant virus libraries were serially passaged in vitro under increasing concentrations of BXA followed by next-generation sequencing to monitor PA amino acid substitutions with increased detection frequencies. Enriched PA amino acid changes were each introduced into a recombinant A (H1N1)pdm09 virus to validate their effect on BXA susceptibility and viral replication fitness in vitro. The I38 T/M substitutions known to confer reduced susceptibility to BXA were invariably detected from recombinant virus libraries within 5 serial passages. In addition, we identified a novel L106R substitution that emerged in the third passage and conferred greater than 10-fold reduced susceptibility to BXA. PA-L106 is highly conserved among seasonal influenza A and B viruses. Compared to the wild-type virus, the L106R substitution resulted in reduced polymerase activity and a minor reduction of the peak viral load, suggesting the amino acid change may result in moderate fitness loss. Our results support the use of deep mutational scanning as a practical tool to elucidate genotype-phenotype relationships, including mapping amino acid substitutions with reduced susceptibility to antivirals.
{"title":"High throughput profiling identified PA-L106R amino acid substitution in A(H1N1)pdm09 influenza virus that confers reduced susceptibility to baloxavir in vitro","authors":"Dongdong Chen , Wen Su , Ka-Tim Choy , Yan Sing Chu , Chi Ho Lin , Hui-Ling Yen","doi":"10.1016/j.antiviral.2024.105961","DOIUrl":"10.1016/j.antiviral.2024.105961","url":null,"abstract":"<div><p>Baloxavir acid (BXA) is a pan-influenza antiviral that targets the cap-dependent endonuclease of the polymerase acidic (PA) protein required for viral mRNA synthesis. To gain a comprehensive understanding on the molecular changes associated with reduced susceptibility to BXA and their fitness profile, we performed a deep mutational scanning at the PA endonuclease domain of an A (H1N1)pdm09 virus. The recombinant virus libraries were serially passaged <em>in vitro</em> under increasing concentrations of BXA followed by next-generation sequencing to monitor PA amino acid substitutions with increased detection frequencies. Enriched PA amino acid changes were each introduced into a recombinant A (H1N1)pdm09 virus to validate their effect on BXA susceptibility and viral replication fitness <em>in vitro</em>. The I38 T/M substitutions known to confer reduced susceptibility to BXA were invariably detected from recombinant virus libraries within 5 serial passages. In addition, we identified a novel L106R substitution that emerged in the third passage and conferred greater than 10-fold reduced susceptibility to BXA. PA-L106 is highly conserved among seasonal influenza A and B viruses. Compared to the wild-type virus, the L106R substitution resulted in reduced polymerase activity and a minor reduction of the peak viral load, suggesting the amino acid change may result in moderate fitness loss. Our results support the use of deep mutational scanning as a practical tool to elucidate genotype-phenotype relationships, including mapping amino acid substitutions with reduced susceptibility to antivirals.</p></div>","PeriodicalId":8259,"journal":{"name":"Antiviral research","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0166354224001700/pdfft?md5=4cdda98322443d54d142f930c2a1c7d6&pid=1-s2.0-S0166354224001700-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141603236","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}
Pub Date : 2024-07-08DOI: 10.1016/j.antiviral.2024.105960
Respiratory syncytial virus is the major cause of respiratory viral infections, particularly in infants, immunocompromised populations, and the elderly (over 65 years old), the prevention of RSV infection has become a priority. In this study, we generated a chimeric influenza virus, termed LAIV/RSV/HA-3F, using reverse genetics technology which contained three repeats of the RSV fusion protein neutralizing epitope site II to the N terminal in the background of the hemagglutinin (HA) gene of cold adapted influenza vaccine A/California/7/2009 ca. LAIV/RSV/HA-3F exhibited cold-adapted (ca) and attenuated (att) phenotype. BALB/c mice immunized intranasally with LAIV/RSV/HA-3F showed robust immunogenicity, inducing viral-specific antibody responses against both influenza and RSV, eliciting RSV-specific humoral, cellular and mucosal immune responses. LAIV/RSV/HA-3F also conferred protection as indicated by reduced viral titers and improved lung histopathological alterations against live RSV virus challenge. Mechanismly, single-cell RNA sequencing (scRNA-seq) and single-cell T cell antigen receptor (TCR) sequencing were employed to characterize the immune responses triggered by chimeric RSV vaccine, displaying that LAIV/RSV/HA-3F provided protection mainly via interferon-γ (IFN-γ). Moreover, we found that LAIV/RSV/HA-3F significantly inhibited viral replication in the challenged lung and protected against subsequent RSV challenge in cotton rats without causing lung disease. Taken together, our findings demonstrated that LAIV/RSV/HA-3F has potential as a promising bivalent vaccine with dual purpose candidate for the prevention of influenza and RSV, and preclinical and clinical studies warrant further investigations.
{"title":"Cold-adapted influenza vaccine carrying three repeats of a respiratory syncytial virus (RSV) fusion glycoprotein epitope site protects BALB/c mice and cotton rats against RSV infection","authors":"","doi":"10.1016/j.antiviral.2024.105960","DOIUrl":"10.1016/j.antiviral.2024.105960","url":null,"abstract":"<div><p>Respiratory syncytial virus is the major cause of respiratory viral infections, particularly in infants, immunocompromised populations, and the elderly (over 65 years old), the prevention of RSV infection has become a priority. In this study, we generated a chimeric influenza virus, termed LAIV/RSV/HA-3F, using reverse genetics technology which contained three repeats of the RSV fusion protein neutralizing epitope site II to the N terminal in the background of the hemagglutinin (HA) gene of cold adapted influenza vaccine A/California/7/2009 ca. LAIV/RSV/HA-3F exhibited cold-adapted (<em>ca</em>) and attenuated (<em>att</em>) phenotype. BALB/c mice immunized intranasally with LAIV/RSV/HA-3F showed robust immunogenicity, inducing viral-specific antibody responses against both influenza and RSV, eliciting RSV-specific humoral, cellular and mucosal immune responses. LAIV/RSV/HA-3F also conferred protection as indicated by reduced viral titers and improved lung histopathological alterations against live RSV virus challenge. Mechanismly, single-cell RNA sequencing (scRNA-seq) and single-cell T cell antigen receptor (TCR) sequencing were employed to characterize the immune responses triggered by chimeric RSV vaccine, displaying that LAIV/RSV/HA-3F provided protection mainly via interferon-γ (IFN-γ). Moreover, we found that LAIV/RSV/HA-3F significantly inhibited viral replication in the challenged lung and protected against subsequent RSV challenge in cotton rats without causing lung disease. Taken together, our findings demonstrated that LAIV/RSV/HA-3F has potential as a promising bivalent vaccine with dual purpose candidate for the prevention of influenza and RSV, and preclinical and clinical studies warrant further investigations.</p></div>","PeriodicalId":8259,"journal":{"name":"Antiviral research","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141578816","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}