4,371 results match your criteria Lymphocytic Choriomeningitis

Identification of potent inhibitors of arenavirus and SARS-CoV-2 exoribonucleases by fluorescence polarization assay.

Antiviral Res 2022 Jun 16;204:105364. Epub 2022 Jun 16.

Université Aix-Marseille, Architecture et Fonction des Macromolécules Biologiques (AFMB) - UMR7257 CNRS - Case 932, 163 avenue de Luminy, Marseille CEDEX 09, 13288, France. Electronic address:

Viral exoribonucleases are uncommon in the world of RNA viruses. To date, they have only been identified in the Arenaviridae and the Coronaviridae families. The exoribonucleases of these viruses play a crucial role in the pathogenicity and interplay with host innate immune response. Read More

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Phase I study of VSV-GP (BI 1831169) as monotherapy or combined with ezabenlimab in advanced and refractory solid tumors.

Future Oncol 2022 Jun 14. Epub 2022 Jun 14.

Department of Internal Medicine VIII, Medical Oncology & Pneumology, University Hospital Tübingen, Germany.

Patients with advanced, recurrent or metastatic cancer have poor prognosis despite treatment advancements. Vesicular stomatitis virus (VSV)-GP (BI 1831169) is a chimeric VSV with its neurotropic glycoprotein G replaced by the non-neurotropic glycoprotein (GP) of the lymphocytic choriomeningitis virus. This live, recombinant oncolytic virus has demonstrated preclinical efficacy as a viral-based immunotherapy due to its interferon-dependent tumor specificity, potent oncolysis and stimulation of antitumor immune activity. Read More

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Congenital lymphocytic choriomeningitis virus: A review.

Prenat Diagn 2022 Jun 13. Epub 2022 Jun 13.

Service de Gynécologie-Obstétrique, Hôpital Louis Mourier, APHP, Université de Paris, Colombes, France.

Introduction: Lymphocytic choriomeningitis virus (LCMV) uses rodents such as mice and hamsters as its principal reservoir. When women acquire LCMV during pregnancy because of contact with rodents, it can lead to congenital LCMV infection, which is associated with high mortality and morbidity. Although the number of cases reported in the literature is increasing, LCMV is rarely mentioned because a history of exposure to rodents is uncommon and mostly unknown. Read More

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Leukocyte cell-derived chemotaxin 2 is an antiviral regulator acting through the proto-oncogene MET.

Nat Commun 2022 Jun 8;13(1):3176. Epub 2022 Jun 8.

Department of Clinical Laboratory Medicine, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.

Retinoic acid-inducible gene (RIG)-I is an essential innate immune sensor that recognises pathogen RNAs and induces interferon (IFN) production. However, little is known about how host proteins regulate RIG-I activation. Here, we show that leukocyte cell-derived chemotaxin 2 (LECT2), a hepatokine and ligand of the MET receptor tyrosine kinase is an antiviral regulator that promotes the RIG-I-mediated innate immune response. Read More

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Viral coinfection promotes tuberculosis immunopathogenesis by type I IFN signaling-dependent impediment of Th1 cell pulmonary influx.

Nat Commun 2022 Jun 7;13(1):3155. Epub 2022 Jun 7.

Department of Microbiology, Graduate School of Medical Science, Brain Korea 21 Project, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is often exacerbated upon coinfection, but the underlying immunological mechanisms remain unclear. Here, to elucidate these mechanisms, we use an Mtb and lymphocytic choriomeningitis virus coinfection model. Viral coinfection significantly suppresses Mtb-specific IFN-γ production, with elevated bacterial loads and hyperinflammation in the lungs. Read More

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Extrafollicular Plasmablasts Present in the Acute Phase of Infections Express High Levels of PD-L1 and Are Able to Limit T Cell Response.

Front Immunol 2022 16;13:828734. Epub 2022 May 16.

Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina.

During infections with protozoan parasites or some viruses, T cell immunosuppression is generated simultaneously with a high B cell activation. It has been described that, as well as producing antibodies, plasmablasts, the differentiation product of activated B cells, can condition the development of protective immunity in infections. Here, we show that, in infection, all the plasmablasts detected during the acute phase of the infection had higher surface expression of PD-L1 than other mononuclear cells. Read More

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[Co-circulation of Junín virus and other mammarenaviruses in a geographical area without confirmed cases of Argentine Hemorrhagic Fever].

Medicina (B Aires) 2022 ;82(3):344-350

Instituto Nacional de Enfermedades Virales Humanas Dr. Julio I. Maiztegui, ANLIS, Pergamino, Buenos Aires, Argentina.

Since the identification of Junin virus in the 1950s, many studies were carried out in wild rodents within the endemic area of the Argentine Hemorrhagic Fever (AHF) that recorded also the activity of the lymphocytic choriomeningitis virus (LCMV) and the Latino virus (LATV). The absence of confirmed cases of AHF since the 1990s in the department of Rio Cuarto, Córdoba province, promoted ecoepidemiological surveillance of infection of Calomys musculinus (Junin virus reservoir) and the search of reservoirs of the other mammarenaviruses. During two years of seasonal sampling, with a capture, mark and release system, 857 rodents were captured, corresponding 57. Read More

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CD4 T-cell epitope-based heterologous prime-boost vaccination potentiates anti-tumor immunity and PD-1/PD-L1 immunotherapy.

J Immunother Cancer 2022 05;10(5)

Institute of Immunology, Third Military Medical University, Chongqing, China

Background: Antitumor therapeutic vaccines are generally based on antigenic epitopes presented by major histocompatibility complex (MHC-I) molecules to induce tumor-specific CD8 T cells. Paradoxically, continuous T cell receptor (TCR) stimulation from tumor-derived CD8 T-cell epitopes can drive the functional exhaustion of tumor-specific CD8 T cells. Tumor-specific type-I helper CD4 T (T1) cells play an important role in the population maintenance and cytotoxic function of exhausted tumor-specific CD8 T cells in the tumor microenvironment. Read More

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Genome-Wide Knockout Screen Identifies Human Sialomucin CD164 as an Essential Entry Factor for Lymphocytic Choriomeningitis Virus.

mBio 2022 May 3:e0020522. Epub 2022 May 3.

Department of Biochemistry and Biophysics, University of California, San Franciscogrid.266102.1, San Francisco, California, USA.

Lymphocytic choriomeningitis virus (LCMV) is a well-studied mammarenavirus that can be fatal in congenital infections. However, our understanding of LCMV and its interactions with human host factors remains incomplete. Here, host determinants affecting LCMV infection were investigated through a genome-wide CRISPR knockout screen in A549 cells, a human lung adenocarcinoma line. Read More

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Chemokine redundancy versus specificity in the context of CXCR3 and its ligands.

Immunol Cell Biol 2022 Apr 25. Epub 2022 Apr 25.

Wellcome Centre for Cell-Matrix Research, Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK.

In a recent article published in Immunology & Cell Biology, Dalit et al. describe how correcting mutations in the C57BL/6 mouse strain can restore production of the chemokine CXCL11, although surprisingly, this expression of CXCL11 had little effect on B and T cells and the innate immune response to infection with lymphocytic choriomeningitis virus or influenza virus. Read More

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High precision-cut liver slice model to study cell-autonomous antiviral defense of hepatocytes within their microenvironment.

JHEP Rep 2022 May 6;4(5):100465. Epub 2022 Mar 6.

Institute of Molecular Immunology and Experimental Oncology, School of Medicine, Technical University of Munich, Germany.

Background & Aims: Increased sensitivity towards tumor necrosis factor (TNF)-induced cell death in virus-infected hepatocytes has revealed a so far unrecognized hepatocyte-intrinsic antiviral immune surveillance mechanism, for which no or model is available. We aimed to establish precision-cut liver slices (PCLS) as a model system to study hepatocyte-intrinsic regulation of apoptosis.

Methods: Preparation of PCLS from mouse and human liver tissue was optimized for minimal procedure-associated apoptosis. Read More

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Cavβ1 regulates T cell expansion and apoptosis independently of voltage-gated Ca channel function.

Nat Commun 2022 04 19;13(1):2033. Epub 2022 Apr 19.

Department of Pathology, NYU Grossman School of Medicine, New York, NY, USA.

TCR stimulation triggers Ca signals that are critical for T cell function and immunity. Several pore-forming α and auxiliary β subunits of voltage-gated Ca channels (VGCC) were reported in T cells, but their mechanism of activation remains elusive and their contribution to Ca signaling in T cells is controversial. We here identify Caβ1, encoded by Cacnb1, as a regulator of T cell function. Read More

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Tissue-resident memory CD8 T cells cooperate with CD4 T cells to drive compartmentalized immunopathology in the CNS.

Sci Transl Med 2022 04 13;14(640):eabl6058. Epub 2022 Apr 13.

Department of Pathology and Immunology, University of Geneva, 1211 Geneva, Switzerland.

In chronic inflammatory diseases of the central nervous system (CNS), immune cells persisting behind the blood-brain barrier are supposed to promulgate local tissue destruction. The drivers of such compartmentalized inflammation remain unclear, but tissue-resident memory T cells (T) represent a potentially important cellular player in this process. Here, we investigated whether resting CD8 T persisting after cleared infection with attenuated lymphocytic choriomeningitis virus (LCMV) can initiate immune responses directed against cognate self-antigen in the CNS. Read More

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Persistence of Virus-Specific Antibody after Depletion of Memory B Cells.

J Virol 2022 05 11;96(9):e0002622. Epub 2022 Apr 11.

Emory Vaccine Center, Emory University School of Medicinegrid.471395.d, Atlanta, Georgia, USA.

Humoral immunity is a major component of the adaptive immune response against viruses and other pathogens with pathogen-specific antibody acting as the first line of defense against infection. Virus-specific antibody levels are maintained by continual secretion of antibody by plasma cells residing in the bone marrow. This raises the important question of how the virus-specific plasma cell population is stably maintained and whether memory B cells are required to replenish plasma cells, balancing their loss arising from their intrinsic death rate. Read More

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Genome Sequences of Five Arenaviruses from Pygmy Mice (Mus minutoides) in Sierra Leone.

Microbiol Resour Announc 2022 May 7;11(5):e0009522. Epub 2022 Apr 7.

MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom.

The genome sequences of five strains of a mammarenavirus were assembled from metagenomic data from pygmy mice (Mus minutoides) captured in Sierra Leone. The nearest fully sequenced relatives of this virus, which was named Seli virus, are lymphocytic choriomeningitis virus, Lunk virus, and Ryukyu virus. Read More

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Promyelocytic leukemia protein is a restriction factor for Junín virus independently of Z matrix protein.

Biochem Biophys Res Commun 2022 05 17;606:168-173. Epub 2022 Mar 17.

Laboratorio de Estrategias Antivirales, Instituto de Química Biológica, Facultad de Ciencias Exactas y Naturales, IQUIBICEN, UBA-CONICET, Buenos Aires, Argentina. Electronic address:

The New World (NW) mammarenavirus Junín (JUNV) is the etiological agent of Argentine hemorrhagic fever, a human endemic disease of Argentina. Promyelocytic leukemia protein (PML) has been reported as a restriction factor for several viruses although the mechanism/s behind PML-mediated antiviral effect may be diverse and are a matter of debate. Previous studies have reported a nuclear to cytoplasm translocation of PML during the murine Old World mammarenavirus lymphocytic choriomeningitis virus (LCMV) infection. Read More

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A case report of human infection with lymphocytic choriomeningitis virus in Israel.

J Med Virol 2022 Aug 12;94(8):4012-4014. Epub 2022 Apr 12.

Infectious Diseases and Control Unit, Samson Assuta Ashdod University Hospital, Ashdod, Israel and Ben Gurion University of the Negev, Beer Sheva, Israel.

Lymphocytic choriomeningitis virus (LCMV) is an often-overlooked cause for viral meningitis but can have severe consequences in certain clinical situations. We present the first documented infection by LCMV in Israel. The epidemiology of LCMV is evolving with a potential for a worldwide endemicity due to the widespread presence of the natural host. Read More

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LCMV induced downregulation of HVEM on antiviral T cells is critical for an efficient effector response.

Eur J Immunol 2022 Jun 18;52(6):924-935. Epub 2022 Apr 18.

Molecular Biomedicine, Institute of Molecular Health Sciences, Department of Biology, ETH Zurich, Zurich, 8093, Switzerland.

T-cell responses against tumors and pathogens are critically shaped by cosignaling molecules providing a second signal. Interaction of herpes virus entry mediator (HVEM, CD270, TNFRSF14) with multiple ligands has been proposed to promote or inhibit T-cell responses and inflammation, dependent on the context. In this study, we show that absence of HVEM did neither affect generation of effector nor maintenance of memory antiviral T cells and accordingly viral clearance upon acute and chronic lymphocytic choriomeningitis virus (LCMV) infection, due to potent HVEM downregulation during infection. Read More

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Echoencephalography of encephalopathy due to congenital lymphocytic choriomeningitis virus.

J Neuroimaging 2022 05 17;32(3):412-419. Epub 2022 Mar 17.

Department of Neurology, Child Neurology Division, University of South Alabama, Mobile, Alabama, USA.

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Replication-Deficient Lymphocytic Choriomeningitis Virus-Vectored Vaccine Candidate for the Induction of T Cell Immunity against .

Int J Mol Sci 2022 Feb 28;23(5). Epub 2022 Feb 28.

Department of Pathology and Immunology, University of Geneva, 1211 Geneva 4, Switzerland.

() represents a major burden to global health, and refined vaccines are needed. Replication-deficient lymphocytic choriomeningitis virus (rLCMV)-based vaccine vectors against cytomegalovirus have proven safe for human use and elicited robust T cell responses in a large proportion of vaccine recipients. Here, we developed an rLCMV vaccine expressing the antigens TB10. Read More

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February 2022

CD164 is a host factor for lymphocytic choriomeningitis virus entry.

Proc Natl Acad Sci U S A 2022 03 2;119(10):e2119676119. Epub 2022 Mar 2.

Department of Microbiology, Harvard Medical School, Boston, MA 02115.

Significance Lymphocytic choriomeningitis virus (LCMV) is the prototypic arenavirus and has been utilized for decades as a model to understand the host immune response against viral infection. LCMV infection can lead to fatal meningitis in immunocompromised people and can lead to congenital birth defects and spontaneous abortion if acquired during pregnancy. Using a genetic screen, we uncover host factors involved in LCMV entry that were previously unknown and are candidate therapeutic targets to combat LCMV infection. Read More

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Arenaviral infection causes bleeding in mice due to reduced serotonin release from platelets.

Sci Signal 2022 02 22;15(722):eabb0384. Epub 2022 Feb 22.

Department of Molecular Medicine, MERU-Roon Research Center for Vascular Biology, Scripps Research, La Jolla, CA 92037, USA.

Bleeding correlates with disease severity in viral hemorrhagic fevers. We found that the increase in type I interferon (IFN-I) in mice caused by infection with the Armstrong strain of lymphocytic choriomeningitis virus (LCMV; an arenavirus) reduced the megakaryocytic expression of genes encoding enzymes involved in lipid biosynthesis ( and ) and a thrombopoietic transcription factor (). The decreased expression of these genes was associated with reduced numbers of circulating platelets and defects in the arachidonic acid synthetic pathway, thereby suppressing serotonin release from δ-granules in platelets. Read More

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February 2022

Clonally Expanded Virus-Specific CD8 T Cells Acquire Diverse Transcriptional Phenotypes During Acute, Chronic, and Latent Infections.

Front Immunol 2022 2;13:782441. Epub 2022 Feb 2.

Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland.

CD8+ T cells play a crucial role in the control and resolution of viral infections and can adopt a wide range of phenotypes and effector functions depending on the inflammatory context and the duration and extent of antigen exposure. Similarly, viral infections can exert diverse selective pressures on populations of clonally related T cells. Technical limitations have nevertheless made it challenging to investigate the relationship between clonal selection and transcriptional phenotypes of virus-specific T cells. Read More

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Single MHC-I Expression Promotes Virus-Induced Liver Immunopathology.

Hepatol Commun 2022 Jul 14;6(7):1620-1633. Epub 2022 Feb 14.

Department of Molecular Medicine II, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany.

Major histocompatibility complex I (MHC-I) molecules present epitopes on the cellular surface of antigen-presenting cells to prime cytotoxic clusters of differentiation 8 (CD8) T cells (CTLs), which then identify and eliminate other cells such as virus-infected cells bearing the antigen. Human hepatitis virus cohort studies have previously identified MHC-I molecules as promising predictors of viral clearance. However, the underlying functional significance of these predictions is not fully understood. Read More

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DExD/H-box helicase 9 intrinsically controls CD8 T cell-mediated antiviral response through noncanonical mechanisms.

Sci Adv 2022 02 9;8(6):eabk2691. Epub 2022 Feb 9.

Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences, Xi'an Jiaotong University, Xi'an, Shaanxi, China.

Upon virus infection, CD8 T cell accumulation is tightly controlled by simultaneous proliferation and apoptosis. However, it remains unclear how TCR signal coordinates these events to achieve expansion and effector cell differentiation. We found that T cell-specific deletion of nuclear helicase Dhx9 led to impaired CD8 T cell survival, effector differentiation, and viral clearance. Read More

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February 2022

Antibody bivalency improves antiviral efficacy by inhibiting virion release independently of Fc gamma receptors.

Cell Rep 2022 02;38(5):110303

Department of Biomedicine - Haus Petersplatz, Division of Experimental Virology, University of Basel, 4009 Basel, Switzerland; Department of Pathology and Immunology, University of Geneva, 1211 Geneva, Switzerland. Electronic address:

Across the animal kingdom, multivalency discriminates antibodies from all other immunoglobulin superfamily members. The evolutionary forces conserving multivalency above other structural hallmarks of antibodies remain, however, incompletely defined. Here, we engineer monovalent either Fc-competent or -deficient antibody formats to investigate mechanisms of protection of neutralizing antibodies (nAbs) and non-neutralizing antibodies (nnAbs) in virus-infected mice. Read More

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February 2022

Development of Tbet- and CD11c-expressing B cells in a viral infection requires T follicular helper cells outside of germinal centers.

Immunity 2022 02 31;55(2):290-307.e5. Epub 2022 Jan 31.

Center for Immunity and Inflammation, Rutgers New Jersey Medical School, Newark, NJ, USA. Electronic address:

TbetCD11c B cells arise during type 1 pathogen challenge, aging, and autoimmunity in mice and humans. Here, we examined the developmental requirements of this B cell subset. In acute infection, T follicular helper (Tfh) cells, but not Th1 cells, drove TbetCD11c B cell generation through proximal delivery of help. Read More

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February 2022

LCVM infection generates tumor antigen-specific immunity and inhibits growth of nonviral tumors.

Oncoimmunology 2022 21;11(1):2029083. Epub 2022 Jan 21.

Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.

Antibodies and T cells specific for tumor-associated antigens (TAA) are found in individuals without cancer but with a history of infections and are associated with lowered cancer risk. We hypothesized that those immune responses were generated to transiently abnormally expressed self-antigens on infected cells (disease-associated antigens, DAA) and later on tumor cells as TAA. We tested this hypothesis in mice with a history of infection with lymphocytic choriomeningitis virus (LCMV) Armstrong strain (Arm) that causes acute infection when injected intraperitoneally or CL-13 strain that establishes chronic infection when injected intravenously. Read More

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Induction of thymic atrophy and loss of thymic output by type-I interferons during chronic viral infection.

Virology 2022 02 24;567:77-86. Epub 2021 Dec 24.

Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, WA, 98101, USA; Department of Pediatrics, Division of Hematology and Oncology, University of Washington, Seattle, WA, 98195, USA. Electronic address:

Type-I interferon (IFN-I) signals exert a critical role in disease progression during viral infections. However, the immunomodulatory mechanisms by which IFN-I dictates disease outcomes remain to be fully defined. Here we report that IFN-I signals mediate thymic atrophy in viral infections, with more severe and prolonged loss of thymic output and unique kinetics and subtypes of IFN-α/β expression in chronic infection compared to acute infection. Read More

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February 2022

A small stem-loop-forming region within the 3'-UTR of a nonpolyadenylated LCMV mRNA promotes translation.

J Biol Chem 2022 02 10;298(2):101576. Epub 2022 Jan 10.

Laboratory of Emerging Viral Diseases, International Research Center for Infectious Diseases, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan; Center for Infectious Disease Education and Research (CiDER), Osaka University, Suita, Osaka, Japan. Electronic address:

Mammalian arenavirus (mammarenavirus) mRNAs are characterized by 5'-capped and 3'-nonpolyadenylated untranslated regions (UTRs). We previously reported that the nonpolyadenylated 3'-UTR of viral mRNA (vmRNA), which is derived from the noncoding intergenic region (IGR), regulates viral protein levels at the posttranscriptional level. This finding provided the basis for the development of novel live-attenuated vaccines (LAVs) against human pathogenic mammarenaviruses. Read More

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February 2022