4,264 results match your criteria Lymphocytic Choriomeningitis

Identification of a T-bet Quiescent Exhausted CD8 T Cell Subpopulation That Can Differentiate into TIM3CX3CR1 Effectors and Memory-like Cells.

J Immunol 2021 Jun 4. Epub 2021 Jun 4.

Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO;

Persistent Ag induces a dysfunctional CD8 T cell state known as "exhaustion" characterized by PD-1 expression. Nevertheless, exhausted CD8 T cells retain functionality through continued differentiation of progenitor into effector cells. However, it remains ill-defined how CD8 T cell effector responses are sustained in situ. Read More

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Serological Evidence of Multiple Zoonotic Viral Infections among Wild Rodents in Barbados.

Pathogens 2021 May 28;10(6). Epub 2021 May 28.

Faculty of Medical Sciences, University of the West Indies, Cave Hill, St. Michael BB11000, Barbados.

Background: Rodents are reservoirs for several zoonotic pathogens that can cause human infectious diseases, including orthohantaviruses, mammarenaviruses and orthopoxviruses. Evidence exists for these viruses circulating among rodents and causing human infections in the Americas, but much less evidence exists for their presence in wild rodents in the Caribbean.

Methods: Here, we conducted serological and molecular investigations of wild rodents in Barbados to determine the prevalence of orthohantavirus, mammarenavirus and orthopoxvirus infections, and the possible role of these rodent species as reservoirs of zoonotic pathogens. Read More

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Lymphocytic Choriomeningitis-Emerging Trends of a Neglected Virus: A Narrative Review.

Trop Med Infect Dis 2021 May 25;6(2). Epub 2021 May 25.

Department of Immunological and Molecular Diagnostics, University Hospital for Infectious Diseases "Dr Fran Mihaljevic", 10000 Zagreb, Croatia.

Lymphocytic choriomeningitis virus (LCMV) is a neglected rodent-borne zoonotic virus distributed worldwide. Since serologic assays are limited to several laboratories, the disease has been underreported, often making it difficult to determine incidence and seroprevalence rates. Although human clinical cases are rarely recorded, LCMV remains an important cause of meningitis in humans. Read More

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Activation of the STAT3 Signaling Pathway by the RNA-Dependent RNA Polymerase Protein of Arenavirus.

Viruses 2021 May 25;13(6). Epub 2021 May 25.

State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, Hubei, China.

Arenaviruses cause chronic and asymptomatic infections in their natural host, rodents, and several arenaviruses cause severe hemorrhagic fever that has a high mortality in infected humans, seriously threatening public health. There are currently no FDA-licensed drugs available against arenaviruses; therefore, it is important to develop novel antiviral strategies to combat them, which would be facilitated by a detailed understanding of the interactions between the viruses and their hosts. To this end, we performed a transcriptomic analysis on cells infected with arenavirus lymphocytic choriomeningitis virus (LCMV), a neglected human pathogen with clinical significance, and found that the signal transducer and activator of transcription 3 (STAT3) signaling pathway was activated. Read More

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Combination of highly antigenic nucleoproteins to inaugurate a cross-reactive next generation vaccine candidate against Arenaviridae family.

Heliyon 2021 May 19;7(5):e07022. Epub 2021 May 19.

Faculty of Biotechnology and Genetic Engineering, Sylhet Agricultural University, Sylhet 3100, Bangladesh.

Arenaviral infections often result lethal hemorrhagic fevers, affecting primarily in African and South American regions. To date, there is no FDA-approved licensed vaccine against arenaviruses and treatments have been limited to supportive therapy. Hence, the study was employed to design a highly immunogenic cross-reactive vaccine against Arenaviridae family using reverse vaccinology approach. Read More

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Suppressive neutrophils require PIM1 for metabolic fitness and survival during chronic viral infection.

Cell Rep 2021 May;35(8):109160

Versiti Blood Research Institute, 8727 West Watertown Plank Rd., Milwaukee, WI 53213, USA; Department of Microbiology and Immunology, Medical College of Wisconsin, 8701 West Watertown Plank Rd., Milwaukee, WI 53226, USA. Electronic address:

The immune response to a chronic viral infection is uniquely tailored to balance viral control and immunopathology. The role of myeloid cells in shaping the response to chronic viral infection, however, is poorly understood. We perform single-cell RNA sequencing of myeloid cells during acute and chronic lymphocytic choriomeningitis virus (LCMV) infection to address this question. Read More

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Lipid-nanoparticle-encapsulated mRNA vaccines induce protective memory CD8 T cells against a lethal viral infection.

Mol Ther 2021 May 14. Epub 2021 May 14.

Department of Microbiology and Immunology, Bluemle Life Science Building, Thomas Jefferson University, Philadelphia, PA 19107, USA. Electronic address:

It is well established that memory CD8 T cells protect susceptible strains of mice from mousepox, a lethal viral disease caused by ectromelia virus (ECTV), the murine counterpart to human variola virus. While mRNA vaccines induce protective antibody (Ab) responses, it is unknown whether they also induce protective memory CD8 T cells. We now show that immunization with different doses of unmodified or N(1)-methylpseudouridine-modified mRNA (modified mRNA) in lipid nanoparticles (LNP) encoding the ECTV gene EVM158 induced similarly strong CD8 T cell responses to the epitope TSYKFESV, albeit unmodified mRNA-LNP had adverse effects at the inoculation site. Read More

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Severe congenital chorioretinitis caused by congenital lymphocytic choriomeningitis virus infection.

Am J Ophthalmol Case Rep 2021 Jun 17;22:101094. Epub 2021 Apr 17.

Baylor College of Medicine, 1 Baylor Plaza, Houston, TX, 77030, USA.

Purpose: To describe a case of congenital lymphocytic choriomeningitis virus (LCMV), a potentially severe and under-diagnosed etiology of congenital chorioretinitis.

Observations: A 5-month old boy presented with esotropia. Examination revealed light perception vision in the right eye and normal fixation and following behavior in the left eye, and a 50PD esotropia with full versions. Read More

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Role of nuclear localization in the regulation and function of T-bet and Eomes in exhausted CD8 T cells.

Cell Rep 2021 May;35(6):109120

Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Institute for Immunology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Parker Institute for Cancer Immunotherapy, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. Electronic address:

The transcription factors T-bet and Eomesodermin (Eomes) regulate CD8 T cell exhaustion through undefined mechanisms. Here, we show that the subcellular localization of T-bet and Eomes dictate their regulatory activity in exhausted T cells (Ts). Ts had a higher ratio of nuclear Eomes:T-bet than memory T cells (Ts) during chronic lymphocytic choriomeningitis virus (LCMV) infection in preclinical cancer models and in human tumors. Read More

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Prevalence and Risk Factors for Lymphocytic Choriomeningitis Virus Infection in Continental Croatian Regions.

Trop Med Infect Dis 2021 Apr 29;6(2). Epub 2021 Apr 29.

Faculty of Medicine, Institute of Microbiology and Immunology, University of Ljubljana, 1000 Ljubljana, Slovenia.

Lymphocytic choriomeningitis virus (LCMV) is a neglected human pathogen associated with aseptic meningitis, severe systemic infections in immunocompromised persons, and congenital anomalies. Data on the prevalence of LCMV infections are scarce. We analyzed the seroprevalence of LCMV in continental Croatian regions. Read More

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Slow viral propagation during initial phase of infection leads to viral persistence in mice.

Commun Biol 2021 Apr 29;4(1):508. Epub 2021 Apr 29.

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

Immune evasion of pathogens can modify the course of infection and impact viral persistence and pathology. Here, using different strains of the lymphocytic choriomeningitis virus (LCMV) model system, we show that slower propagation results in limited type I interferon (IFN-I) production and viral persistence. Specifically, cells infected with LCMV-Docile exhibited reduced viral replication when compared to LCMV-WE and as a consequence, infection with LCMV-Docile resulted in reduced activation of bone marrow derived dendritic cells (BMDCs) and IFN-I production in vitro in comparison with LCMV-WE. Read More

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Special Issue "Arenaviruses 2020".

Viruses 2021 04 18;13(4). Epub 2021 Apr 18.

Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA.

Rodent-borne arenaviruses have been traditionally predominantly associated with certain muroid species from genera (African arenaviruses) or with species that belong to murid subfamily (New World arenaviruses) [... Read More

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A unified atlas of CD8 T cell dysfunctional states in cancer and infection.

Mol Cell 2021 06 22;81(11):2477-2493.e10. Epub 2021 Apr 22.

Computational and Systems Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA. Electronic address:

CD8 T cells play an essential role in defense against viral and bacterial infections and in tumor immunity. Deciphering T cell loss of functionality is complicated by the conspicuous heterogeneity of CD8 T cell states described across experimental and clinical settings. By carrying out a unified analysis of over 300 assay for transposase-accessible chromatin sequencing (ATAC-seq) and RNA sequencing (RNA-seq) experiments from 12 studies of CD8 T cells in cancer and infection, we defined a shared differentiation trajectory toward dysfunction and its underlying transcriptional drivers and revealed a universal early bifurcation of functional and dysfunctional T cell states across models. Read More

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UTX promotes CD8 T cell-mediated antiviral defenses but reduces T cell durability.

Cell Rep 2021 Apr;35(2):108966

Department of Genetics, UNC-Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Department of Microbiology & Immunology, UNC-Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, UNC-Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA. Electronic address:

Persistent virus infections can cause pathogenesis that is debilitating or lethal. During these infections, virus-specific T cells fail to protect due to weakened antiviral activity or failure to persist. These outcomes are governed by histone modifications, although it is unknown which enzymes contribute to T cell loss or impaired function over time. Read More

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The Janus Kinase Inhibitor Ruxolitinib Prevents Terminal Shock in a Mouse Model of Arenavirus Hemorrhagic Fever.

Microorganisms 2021 Mar 9;9(3). Epub 2021 Mar 9.

Department of Biomedicine-Haus Petersplatz, Division of Experimental Virology, University of Basel, 4009 Basel, Switzerland.

Arenaviruses such as Lassa virus cause arenavirus hemorrhagic fever (AVHF), but protective vaccines and effective antiviral therapy remain unmet medical needs. Our prior work has revealed that inducible nitric oxide synthase (iNOS) induction by IFN-γ represents a key pathway to microvascular leak and terminal shock in AVHF. Here we hypothesized that Ruxolitinib, an FDA-approved JAK inhibitor known to prevent IFN-γ signaling, could be repurposed for host-directed therapy in AVHF. Read More

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Heterologous arenavirus vector prime-boost overrules self-tolerance for efficient tumor-specific CD8 T cell attack.

Cell Rep Med 2021 Mar 3;2(3):100209. Epub 2021 Mar 3.

University of Basel, Department of Biomedicine, Basel, Switzerland.

Therapeutic vaccination regimens inducing clinically effective tumor-specific CD8 T lymphocyte (CTL) responses are an unmet medical need. We engineer two distantly related arenaviruses, Pichinde virus and lymphocytic choriomeningitis virus, for therapeutic cancer vaccination. In mice, life-replicating vector formats of these two viruses delivering a self-antigen in a heterologous prime-boost regimen induce tumor-specific CTL responses up to 50% of the circulating CD8 T cell pool. Read More

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Immunoproteasome Upregulation Is Not Required to Control Protein Homeostasis during Viral Infection.

J Immunol 2021 Apr 17;206(8):1697-1708. Epub 2021 Mar 17.

Division of Immunology, Department of Biology, University of Konstanz, 78457 Konstanz, Germany; and.

The prime function of proteasomes is the control of protein homeostasis in cells (i.e., the removal of proteins that are not properly folded, damaged by stress conditions like reactive oxygen species formation, or degraded on the basis of regular protein turnover). Read More

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Opposing effects of T cell receptor signal strength on CD4 T cells responding to acute versus chronic viral infection.

Elife 2021 Mar 8;10. Epub 2021 Mar 8.

Immune Cell Biology Laboratory, Department of Biomedicine, University of Basel, University Hospital Basel, Basel, Switzerland.

A hallmark of adaptive immunity is CD4 T cells' ability to differentiate into specialized effectors. A long-standing question is whether T cell receptor (TCR) signal strength can dominantly instruct the development of Th1 and T follicular helper (Tfh) cells across distinct infectious contexts. We characterized the differentiation of murine CD4 TCR transgenic T cells responding to altered peptide ligand lymphocytic choriomeningitis viruses (LCMV) derived from acute and chronic parental strains. Read More

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Identification of potential novel hosts and the risk of infection with lymphocytic choriomeningitis virus in humans in Gabon, Central Africa.

Int J Infect Dis 2021 Apr 2;105:452-459. Epub 2021 Mar 2.

Department of Emerging Infectious Diseases, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan; Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan; National Research Center for the Control and Prevention of Infectious Diseases (CCPID), Nagasaki University, Nagasaki, Japan. Electronic address:

Objectives: Lymphocytic choriomeningitis virus (LCMV), a human pathogenic arenavirus, is distributed worldwide. However, no human cases have been reported in Africa. This study aimed to investigate the current situation and potential risks of LCMV infection in Gabon, Central Africa. Read More

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Role of in the transmission of several pathogens in poultry farms.

Int J Parasitol Parasites Wildl 2021 Apr 27;14:130-136. Epub 2021 Jan 27.

Laboratorio de Ecología de Poblaciones, Departamento de Ecología, Genética y Evolución, Instituto IEGEBA (CONICET-UBA), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Ciudad Autónoma de Buenos Aires, Argentina.

This study aimed to analyze the role of as a host of spp., lymphocytic choriomeningitis virus (LCMV) and , in poultry farms of Buenos Aires province, Argentina, and to assess the potential risk of transmission to humans and domestic or breeding animals. Samplings were performed between 2009 and 2011 (S1) and during 2016 (S2). Read More

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converts endogenous neural stem cells to neurons with synaptic formation after spinal cord injury.

iScience 2021 Feb 20;24(2):102074. Epub 2021 Jan 20.

Department of Neurosurgery, Nagoya University School of Medicine, Nagoya, Japan.

The transcriptome analysis of injured tadpole and mice suggested that ., a basic-helix-loop-helix transcription factor, was the most promising transcription factor to exert neuroregeneration after spinal cord injury (SCI) in mammals. We generated a pseudotyped retroviral vector with the neurotropic lymphocytic choriomeningitis virus (LCMV) envelope to deliver murine to mice undergoing SCI. Read More

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February 2021

High levels of soluble CD25 in COVID-19 severity suggest a divergence between anti-viral and pro-inflammatory T-cell responses.

Clin Transl Immunology 2021 15;10(2):e1251. Epub 2021 Feb 15.

The University of Queensland Diamantina Institute Faculty of Medicine The University of Queensland Brisbane QLD Australia.

Objectives: We aimed to gain an understanding of the paradox of the immunity in COVID-19 patients with T cells showing both functional defects and hyperactivation and enhanced proliferation.

Methods: A total of 280 hospitalised patients with COVID-19 were evaluated for cytokine profiles and clinical features including viral shedding. A mouse model of acute infection by lymphocytic choriomeningitis virus (LCMV) was applied to dissect the relationship between immunological, virological and pathological features. Read More

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February 2021

BACH2 enforces the transcriptional and epigenetic programs of stem-like CD8 T cells.

Nat Immunol 2021 03 11;22(3):370-380. Epub 2021 Feb 11.

Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.

During chronic infection and cancer, a self-renewing CD8 T cell subset maintains long-term immunity and is critical to the effectiveness of immunotherapy. These stem-like CD8 T cells diverge from other CD8 subsets early after chronic viral infection. However, pathways guarding stem-like CD8 T cells against terminal exhaustion remain unclear. Read More

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Lassa Virus Vaccine Candidate ML29 Generates Truncated Viral RNAs Which Contribute to Interfering Activity and Attenuation.

Viruses 2021 01 30;13(2). Epub 2021 Jan 30.

Center for Predictive Medicine for Biodefense and Emerging Infectious diseases, University of Louisville, Louisville, KY 40202, USA.

Defective interfering particles (DIPs) are naturally occurring products during virus replication in infected cells. DIPs contain defective viral genomes (DVGs) and interfere with replication and propagation of their corresponding standard viral genomes by competing for viral and cellular resources, as well as promoting innate immune antiviral responses. Consequently, for many different viruses, including mammarenaviruses, DIPs play key roles in the outcome of infection. Read More

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January 2021

Non-neutralizing antibodies protect against chronic LCMV infection by promoting infection of inflammatory monocytes in mice.

Eur J Immunol 2021 Jun 19;51(6):1423-1435. Epub 2021 Feb 19.

Institute of Microbiology, ETH Zürich, Zurich, Switzerland.

Antibodies play an important role in host defense against microorganisms. Besides direct microbicidal activities, antibodies can also provide indirect protection via crosstalk to constituents of the adaptive immune system. Similar to many human chronic viral infections, persistence of Lymphocytic choriomeningitis virus (LCMV) is associated with compromised T- and B-cell responses. Read More

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Fibronectin fibers are highly tensed in healthy organs in contrast to tumors and virus-infected lymph nodes.

Matrix Biol Plus 2020 Nov 17;8:100046. Epub 2020 Jul 17.

Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department of Health Sciences and Technology, ETH Zurich, CH-8093 Zurich, Switzerland.

The extracellular matrix (ECM) acts as reservoir for a plethora of growth factors and cytokines some of which are hypothesized to be regulated by ECM fiber tension. Yet, ECM fiber tension has never been mapped in healthy versus diseased organs. Using our recently developed tension nanoprobe derived from the bacterial adhesin FnBPA5, which preferentially binds to structurally relaxed fibronectin fibers, we discovered here that fibronectin fibers are kept under high tension in selected healthy mouse organs. Read More

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November 2020

Screening of Botanical Drugs against Lassa Virus Entry.

J Virol 2021 Feb 3. Epub 2021 Feb 3.

State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan 430071, China

Lassa virus (LASV) belongs to the Old World genus (family ). At present, there are no approved drugs or vaccines specific for LASV. In this study, high-throughput screening of a botanical drug library was performed against LASV entry using a pseudotype virus bearing the LASV envelope glycoprotein complex (GPC). Read More

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February 2021

Th2 cells lacking T-bet suppress naive and memory T cell responses via IL-10.

Proc Natl Acad Sci U S A 2021 02;118(6)

Experimental Immunology and Osteoarthritis Research, Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany;

Exacerbated immune responses and loss of self-tolerance lead to the development of autoimmunity and immunopathology. Novel therapies to target autoreactive T cells are still needed. Here, we report that Th2-polarized T cells lacking the transcription factor T-bet harbor strong immunomodulatory potential and suppress antigen-specific CD8 T cells via IL-10. Read More

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February 2021

Recombinant lymphocytic choriomeningitis virus-based vaccine vector protects type I interferon receptor deficient mice from viral challenge.

Vaccine 2021 02 29;39(8):1257-1264. Epub 2021 Jan 29.

Institute of Immunobiology, Kantonsspital St.Gallen, Rorschacher Strasse 95, 9007 St.Gallen, Switzerland; Department of Dermatology, University Hospital Zurich, Gloriastrasse 31, 8091 Zurich, Switzerland; Department of Oncology and Hematology, Kantonsspital St.Gallen, Rorschacher Strasse 95, 9007 St.Gallen, Switzerland; Department of Dermatology, Kantonsspital St.Gallen, Rorschacher Strasse 95, 9007 St.Gallen, Switzerland. Electronic address:

Reverse genetically engineered recombinant lymphocytic choriomeningitis virus (rLCMV) is a novel vaccine vector platform. Here, we investigate the safety and efficacy of rLCMV in mice lacking a functional type I interferon system with high susceptibility to viral infections. Propagation-deficient rLCMV vector expressing ovalbumin as a model antigen is cleared from type I interferon receptor-deficient mice (Ifnar) within seven days post vaccination. Read More

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February 2021

The NF-κB regulator Bcl-3 restricts terminal differentiation and promotes memory cell formation of CD8+ T cells during viral infection.

PLoS Pathog 2021 01 28;17(1):e1009249. Epub 2021 Jan 28.

Immune Activation Section, Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America.

Bcl-3 is an atypical member of the IκB family that acts in the nucleus to modulate transcription of many NF-κB targets in a highly context-dependent manner. Accordingly, complete Bcl-3-/- mice have diverse defects in both innate and adaptive immune responses; however, direct effects of Bcl-3 action in individual immune cell types have not been clearly defined. Here, we document a cell-autonomous role for Bcl-3 in CD8+ T cell differentiation during the response to lymphocytic choriomeningitis virus infection. Read More

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January 2021