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Biomedicine & Pharmacotherapy =... Oct 2023Mammarenaviruses are enveloped RNA viruses that can be associated with rodent-transmitted diseases in humans. Their virions are composed of a nucleocapsid surrounded by... (Review)
Review
Mammarenaviruses are enveloped RNA viruses that can be associated with rodent-transmitted diseases in humans. Their virions are composed of a nucleocapsid surrounded by a lipid bilayer with glycoprotein (GP) spikes interacting with receptors on target cells. Both the GP and receptors are highly glycosylated, with glycosylation patterns being crucial for virus binding and cell entry, viral tropism, immune responses, or therapy strategies. These effects have been previously described for several different viruses. In case of arenaviruses, they remain insufficiently understood. Thus, it is important to determine the mechanisms of glycosylation of viral proteins and receptors responsible for infection, in order to fully understand the biology of arenaviruses. In this article, we have summarized and critically evaluated the available literature data on the glycosylation of mammarenavirus-associated proteins to facilitate further research in this field.
Topics: Humans; Glycosylation; Virus Internalization; Receptors, Cell Surface; Arenaviridae Infections; Glycoproteins
PubMed: 37586116
DOI: 10.1016/j.biopha.2023.115196 -
Nature Communications Sep 2023Lassa virus is a member of the Arenaviridae family, which causes human infections ranging from asymptomatic to severe hemorrhagic disease with a high case fatality rate....
Lassa virus is a member of the Arenaviridae family, which causes human infections ranging from asymptomatic to severe hemorrhagic disease with a high case fatality rate. We have designed and generated lipid nanoparticle encapsulated, modified mRNA vaccines that encode for the wild-type Lassa virus strain Josiah glycoprotein complex or the prefusion stabilized conformation of the Lassa virus glycoprotein complex. Hartley guinea pigs were vaccinated with two 10 µg doses, 28 days apart, of either construct. Vaccination induced strong binding antibody responses, specific to the prefusion conformation of glycoprotein complex, which were significantly higher in the prefusion stabilized glycoprotein complex construct group and displayed strong Fc-mediated effects. However, Lassa virus-neutralizing antibody activity was detected in some but not all animals. Following the challenge with a lethal dose of the Lassa virus, all vaccinated animals were protected from death and severe disease. Although the definitive mechanism of protection is still unknown, and assessment of the cell-mediated immune response was not investigated in this study, these data demonstrate the promise of mRNA as a vaccine platform against the Lassa virus and that protection against Lassa virus can be achieved in the absence of virus-neutralizing antibodies.
Topics: Humans; Guinea Pigs; Animals; Lassa virus; Antibodies, Neutralizing; Arenaviridae; mRNA Vaccines; Glycoproteins
PubMed: 37699929
DOI: 10.1038/s41467-023-41376-6 -
Nature Microbiology Mar 2024Infection with Lassa virus (LASV) can cause Lassa fever, a haemorrhagic illness with an estimated fatality rate of 29.7%, but causes no or mild symptoms in many...
Infection with Lassa virus (LASV) can cause Lassa fever, a haemorrhagic illness with an estimated fatality rate of 29.7%, but causes no or mild symptoms in many individuals. Here, to investigate whether human genetic variation underlies the heterogeneity of LASV infection, we carried out genome-wide association studies (GWAS) as well as seroprevalence surveys, human leukocyte antigen typing and high-throughput variant functional characterization assays. We analysed Lassa fever susceptibility and fatal outcomes in 533 cases of Lassa fever and 1,986 population controls recruited over a 7 year period in Nigeria and Sierra Leone. We detected genome-wide significant variant associations with Lassa fever fatal outcomes near GRM7 and LIF in the Nigerian cohort. We also show that a haplotype bearing signatures of positive selection and overlapping LARGE1, a required LASV entry factor, is associated with decreased risk of Lassa fever in the Nigerian cohort but not in the Sierra Leone cohort. Overall, we identified variants and genes that may impact the risk of severe Lassa fever, demonstrating how GWAS can provide insight into viral pathogenesis.
Topics: Humans; Lassa Fever; Genome-Wide Association Study; Seroepidemiologic Studies; Lassa virus; Fever; Human Genetics
PubMed: 38326571
DOI: 10.1038/s41564-023-01589-3 -
Journal of Medical Virology Nov 2023The emerging viruses SARS-CoV-2 and arenaviruses cause severe respiratory and hemorrhagic diseases, respectively. The production of infectious particles of both viruses...
The emerging viruses SARS-CoV-2 and arenaviruses cause severe respiratory and hemorrhagic diseases, respectively. The production of infectious particles of both viruses and virus spread in tissues requires cleavage of surface glycoproteins (GPs) by host proprotein convertases (PCs). SARS-CoV-2 and arenaviruses rely on GP cleavage by PCs furin and subtilisin kexin isozyme-1/site-1 protease (SKI-1/S1P), respectively. We report improved luciferase-based reporter cell lines, named luminescent inducible proprotein convertase reporter cells that we employ to monitor PC activity in its authentic subcellular compartment. Using these sensor lines we screened a small compound library in high-throughput manner. We identified 23 FDA-approved small molecules, among them monensin which displayed broad activity against furin and SKI-1/S1P. Monensin inhibited arenaviruses and SARS-CoV-2 in a dose-dependent manner. We observed a strong reduction in infectious particle release upon monensin treatment with little effect on released genome copies. This was reflected by inhibition of SARS-CoV-2 spike processing suggesting the release of immature particles. In a proof of concept experiment using human precision cut lung slices, monensin potently inhibited SARS-CoV-2 infection, evidenced by reduced infectious particle release. We propose that our PC sensor pipeline is a suitable tool to identify broad-spectrum antivirals with therapeutic potential to combat current and future emerging viruses.
Topics: Humans; Furin; Viral Envelope Proteins; Monensin; Arenavirus; Antiviral Agents
PubMed: 37975336
DOI: 10.1002/jmv.29211 -
Molecular Therapy : the Journal of the... Feb 2024Harnessing the immune system to eradicate tumors requires identification and targeting of tumor antigens, including tumor-specific neoantigens and tumor-associated...
Harnessing the immune system to eradicate tumors requires identification and targeting of tumor antigens, including tumor-specific neoantigens and tumor-associated self-antigens. Tumor-associated antigens are subject to existing immune tolerance, which must be overcome by immunotherapies. Despite many novel immunotherapies reaching clinical trials, inducing self-antigen-specific immune responses remains challenging. Here, we systematically investigate viral-vector-based cancer vaccines encoding a tumor-associated self-antigen (TRP2) for the treatment of established melanomas in preclinical mouse models, alone or in combination with adoptive T cell therapy. We reveal that, unlike foreign antigens, tumor-associated antigens require replication of lymphocytic choriomeningitis virus (LCMV)-based vectors to break tolerance and induce effective antigen-specific CD8 T cell responses. Immunization with a replicating LCMV vector leads to complete tumor rejection when combined with adoptive TRP2-specific T cell transfer. Importantly, immunization with replicating vectors leads to extended antigen persistence in secondary lymphoid organs, resulting in efficient T cell priming, which renders previously "cold" tumors open to immune infiltration and reprograms the tumor microenvironment to "hot." Our findings have important implications for the design of next-generation immunotherapies targeting solid cancers utilizing viral vectors and adoptive cell transfer.
Topics: Mice; Animals; Lymphocytic choriomeningitis virus; CD8-Positive T-Lymphocytes; Neoplasms; Antigens, Neoplasm; Cancer Vaccines; Autoantigens; Tumor Microenvironment
PubMed: 38058126
DOI: 10.1016/j.ymthe.2023.11.026 -
The Journal of General Virology Aug 2023In April 2023, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum was amended and emended....
In April 2023, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum was amended and emended. The phylum was expanded by one new family, 14 new genera, and 140 new species. Two genera and 538 species were renamed. One species was moved, and four were abolished. This article presents the updated taxonomy of as now accepted by the ICTV.
Topics: Negative-Sense RNA Viruses; RNA Viruses; RNA-Dependent RNA Polymerase
PubMed: 37622664
DOI: 10.1099/jgv.0.001864 -
Optimal reference genes for RNA tissue analysis in small animal models of hemorrhagic fever viruses.Scientific Reports Nov 2023Reverse-transcription quantitative polymerase chain reaction assays are frequently used to evaluate gene expression in animal model studies. Data analyses depend on...
Reverse-transcription quantitative polymerase chain reaction assays are frequently used to evaluate gene expression in animal model studies. Data analyses depend on normalization using a suitable reference gene (RG) to minimize effects of variation due to sample collection, sample processing, or experimental set-up. Here, we investigated the suitability of nine potential RGs in laboratory animals commonly used to study viral hemorrhagic fever infection. Using tissues (liver, spleen, gonad [ovary or testis], kidney, heart, lung, eye, brain, and blood) collected from naïve animals and those infected with Crimean-Congo hemorrhagic fever (mice), Nipah (hamsters), or Lassa (guinea pigs) viruses, optimal species-specific RGs were identified based on five web-based algorithms to assess RG stability. Notably, the Ppia RG demonstrated stability across all rodent tissues tested. Optimal RG pairs that include Ppia were determined for each rodent species (Ppia and Gusb for mice; Ppia and Hrpt for hamsters; and Ppia and Gapdh for guinea pigs). These RG pair assays were multiplexed with viral targets to improve assay turnaround time and economize sample usage. Finally, a pan-rodent Ppia assay capable of detecting Ppia across multiple rodent species was developed and successfully used in ecological investigations of field-caught rodents, further supporting its pan-species utility.
Topics: Cricetinae; Female; Male; Guinea Pigs; Animals; Mice; Hemorrhagic Fever Virus, Crimean-Congo; Dengue Virus; Models, Animal; Arenaviruses, New World; Cyclophilin A; RNA
PubMed: 37938597
DOI: 10.1038/s41598-023-45740-w -
Journal of Infection and Public Health Dec 2023Multiplex real-time PCR is a quick and cost effective method for detection of various gene simultaneously. HFSV (Hemorrhagic Fever Syndrome Virus) is a newly emerging...
BACKGROUND
Multiplex real-time PCR is a quick and cost effective method for detection of various gene simultaneously. HFSV (Hemorrhagic Fever Syndrome Virus) is a newly emerging infectious disease because of globalization and climate change. We tried to develop a molecular diagnostic technique for various causative viruses and evaluate its usefulness for improving public health.
METHODS
Molecular diagnostic test method that qualitatively detects viruses causing viral hemorrhagic fevers hired Taq-Man Real-time RT-PCR technique. The Ct value was experimentally observed three or more times at the RNA concentration before and after the detection limit. After designing a multiplex real-time RT-PCR test for target gene of selected 17 viruses, the detection limit for each target and the presence or absence of cross-reaction and interference reaction were evaluated to determine its availability.
RESULTS
Six kinds of viruses, including Crimean-Congo hemorrhagic fever virus, Omsk hemorrhagic fever virus, Sabia virus, Chapare virus, Yellow fever virus, and Variola virus (A4L gene, B12R gene), were able to confirm the detection limit of 0.5 copies/μl, and other Ebola virus, Marburg virus, Rift Valley fever virus, Kyasanur Forest disease virus, Junin virus, Guanarito virus, Machupo virus, Chikungunya virus, Hantavirus, Dengue virus types 1-4, and Lassa virus (L gene, GPC gene), and 11 kinds of viruses, the detection limit was confirmed at 5 copies/μl. No cross-reaction or interference between detected genes was observed.
CONCLUSION
The virus test method developed through this study using multiplex is expected to be used for public health and quarantine as a test method that can be used when a hemorrhagic fever virus of unknown cause is introduced.
Topics: Animals; Humans; Hemorrhagic Fever Virus, Crimean-Congo; Dengue Virus; Viruses; Arenaviruses, New World; Orthohantavirus; Polymerase Chain Reaction
PubMed: 37866271
DOI: 10.1016/j.jiph.2023.10.012 -
The Journal of Allergy and Clinical... Jan 2024Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory disorder characterized by a life-threatening cytokine storm and immunopathology. Familial HLH type 3...
BACKGROUND
Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory disorder characterized by a life-threatening cytokine storm and immunopathology. Familial HLH type 3 (FHL3) accounts for approximately 30% of all inborn HLH cases worldwide. It is caused by mutations in the UNC13D gene that result in impaired degranulation of cytotoxic vesicles and hence compromised T-cell- and natural killer-cell-mediated killing. Current treatment protocols, including allogeneic hematopoietic stem cell (HSC) transplantation, still show high mortality.
OBJECTIVE
We sought to develop and evaluate a curative genome editing strategy in the preclinical FHL3 Jinx mouse model. Jinx mice harbor a cryptic splice donor site in Unc13d intron 26 and develop clinical symptoms of human FHL3 upon infection with lymphocytic choriomeningitis virus (LCMV).
METHODS
We employed clustered regularly interspaced short palindromic repeats (CRISPR)-Cas technology to delete the disease-causing mutation in HSCs and transplanted Unc13d-edited stem cells into busulfan-conditioned Jinx recipient mice. Safety studies included extensive genotyping and chromosomal aberrations analysis by single targeted linker-mediated PCR sequencing (CAST-Seq)-based off-target analyses. Cure from HLH predisposition was assessed by LCMV infection.
RESULTS
Hematopoietic cells isolated from transplanted mice revealed efficient gene editing (>95%), polyclonality of the T-cell receptor repertoire, and neither signs of off-target effects nor leukemogenesis. Unc13d transcription levels of edited and wild-type cells were comparable. While LCMV challenge resulted in acute HLH in Jinx mice transplanted with mock-edited HSCs, Jinx mice grafted with Unc13d-edited cells showed rapid virus clearance and protection from HLH.
CONCLUSIONS
Our study demonstrates that transplantation of CRISPR-Cas edited HSCs supports the development of a functional polyclonal T-cell response in the absence of genotoxicity-associated clonal outgrowth.
Topics: Humans; Mice; Animals; Lymphohistiocytosis, Hemophagocytic; T-Lymphocytes; Gene Editing; Mutation; Lymphocytic choriomeningitis virus; Hematopoietic Stem Cells; Membrane Proteins
PubMed: 37595758
DOI: 10.1016/j.jaci.2023.08.003 -
Methods in Molecular Biology (Clifton,... 2024Several mammarenaviruses cause hemorrhagic fever (HF) disease in humans and pose a significant public health problem in their endemic regions. The Old World (OW)...
Several mammarenaviruses cause hemorrhagic fever (HF) disease in humans and pose a significant public health problem in their endemic regions. The Old World (OW) mammarenavirus Lassa virus (LASV) is estimated to infect several hundred thousand people yearly in West Africa, resulting in high numbers of Lassa fever (LF) cases, a disease associated with high morbidity and mortality. No licensed vaccines are available to combat LASV infection, and anti-LASV drug therapy is limited to the off-label use of ribavirin whose efficacy remains controversial. The development of reverse genetics approaches has provided investigators with a powerful approach for the investigation of the molecular, cell biology and pathogenesis of mammarenaviruses. The use of cell-based minigenome systems has allowed examining the cis- and trans-acting factors involved in viral genome replication and gene transcription, assembly, and budding, which has facilitated the identification of several anti-mammarenavirus candidate drugs. Likewise, it is possible now to rescue infectious recombinant mammarenaviruses from cloned cDNAs containing predetermined mutations in their genomes to investigate virus-host interactions and mechanisms of viral pathogenesis. Reverse genetics have also allowed the generation of mammarenaviruses expressing foreign genes to facilitate virus detection, to identify antiviral drugs, and to generate live-attenuated vaccine (LAV) candidates. Likewise, reverse genetics techniques have allowed the generation of single-cycle infectious, reporter-expressing mammarenaviruses to study some aspects of the biology of HF-causing human mammarenavirus without the need of high security biocontainment laboratories. In this chapter, we describe the experimental procedures to generate recombinant (r)LASV using state-of-the-art plasmid-based reverse genetics.
Topics: Humans; Lassa virus; Reverse Genetics; Arenaviridae; Lassa Fever; Hemorrhagic Fevers, Viral; Plasmids
PubMed: 38064030
DOI: 10.1007/978-1-0716-3533-9_8