scholarly journals Farnesoid X Receptor in Mice Prevents Severe Liver Immunopathology During Lymphocytic Choriomeningitis Virus Infection

2017 ◽  
Vol 41 (1) ◽  
pp. 323-338 ◽  
Author(s):  
Nadine Honke ◽  
Namir Shaabani ◽  
Cornelia Hardt ◽  
Caroline Krings ◽  
Dieter Häussinger ◽  
...  
Keyword(s):  
T Cell ◽  
Lymphocytic Choriomeningitis ◽  
Lymphocytic Choriomeningitis Virus ◽  
Farnesoid X Receptor ◽  
Toxic Effects ◽  
Type I ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Lymphocytic Choriomeningitis Virus Infection

Background: Bile acids (BAs) are steroid molecules that are synthesized in the liver. In addition to their important role as a surfactant in solubilizing lipids and promoting the absorption of lipids in the gastrointestinal tract, they act as inflammagens. The role of BAs and their receptor farnesoid X receptor (FXR) during viral infection has not been studied in detail. Methods: By using FXR-deficient mice, we investigated the role of bile acid receptor FXR during infection with lymphocytic choriomeningitis virus (LCMV). The importance of FXR in inducing IFN-I and monocytes proliferation were investigated and viral titers and T cell exhaustion were analyzed at different time points. Results: This study shows that controlled levels of BAs activate FXR in hepatocytes and FXR in response upregulates the production of type I interferon. In turn, FXR maintains BAs within a balanced range to inhibit their toxic effects. The absence of FXR results in high levels of BAs, which inhibit the proliferation of monocytes and result in a defect in viral elimination, consequently leading to T cell exhaustion. Conclusion: We found that FXR contributes to IFN-I production in hepatocytes and balances BA levels to inhibit their toxic effects on monocytes.

scholarly journals Critical Role for Alpha/Beta and Gamma Interferons in Persistence of Lymphocytic Choriomeningitis Virus by Clonal Exhaustion of Cytotoxic T Cells

2001 ◽  
Vol 75 (18) ◽  
pp. 8407-8423 ◽  
Author(s):  
Rong Ou ◽  
Shenghua Zhou ◽  
Lei Huang ◽  
Demetrius Moskophidis
Keyword(s):  
T Cells ◽  
T Cell ◽  
Critical Role ◽  
Lymphocytic Choriomeningitis ◽  
Lymphocytic Choriomeningitis Virus ◽  
Interferon Response ◽  
Type I ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Alpha Beta

ABSTRACT Under conditions of high antigenic load during infection with invasive lymphocytic choriomeningitis virus (LCMV) strains, virus can persist by selective clonal exhaustion of antigen-specific CD8+ T cells. In this work we studied the down-regulation of the virus-specific CD8+-T-cell response during a persistent infection of adult mice, with particular emphasis on the contribution of the interferon response in promoting host defense. Studies were conducted by infecting mice deficient in receptors for type I (alpha/beta interferon [IFN-α/β]), type II (IFN-γ), and both type I and II IFNs with LCMV isolates that vary in their capacity to induce T-cell exhaustion. The main conclusions of this study are as follows. (i) IFNs play a critical role in LCMV infection by reducing viral loads in the initial stages of infection and thus modifying both the extent of CD8+-T-cell exhaustion and the course of infection. The importance of IFNs in this context varies with the biological properties of the LCMV strain. (ii) An inverse correlation exists between antigen persistence and responsiveness of virus-specific CD8+ T cells. This results in distinct programs of activation or tolerance (functional unresponsiveness and/or physical elimination of antigen-specific cells) during acute and chronic virus infections, respectively. (iii) A successful immune response associated with definitive viral clearance requires an appropriate balance between cellular and humoral components of the immune system. We discuss the role of IFNs in influencing virus-specific T cells that determine the outcome of persistent infections.

scholarly journals IRF9 Prevents CD8+ T Cell Exhaustion in an Extrinsic Manner during Acute Lymphocytic Choriomeningitis Virus Infection

2017 ◽  
Vol 91 (22) ◽  
Author(s):  
Magdalena Huber ◽  
Tamara Suprunenko ◽  
Thomas Ashhurst ◽  
Felix Marbach ◽  
Hartmann Raifer ◽  
...  
Keyword(s):  
Transcription Factor ◽  
T Cell ◽  
Viral Infection ◽  
Chronic Infection ◽  
Acute Infection ◽  
Lymphocytic Choriomeningitis ◽  
Type I ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Deficient Mice

ABSTRACT Effective CD8+ T cell responses play an important role in determining the course of a viral infection. Overwhelming antigen exposure can result in suboptimal CD8+ T cell responses, leading to chronic infection. This altered CD8+ T cell differentiation state, termed exhaustion, is characterized by reduced effector function, upregulation of inhibitory receptors, and altered expression of transcription factors. Prevention of overwhelming antigen exposure to limit CD8+ T cell exhaustion is of significant interest for the control of chronic infection. The transcription factor interferon regulatory factor 9 (IRF9) is a component of type I interferon (IFN-I) signaling downstream of the IFN-I receptor (IFNAR). Using acute infection of mice with lymphocytic choriomeningitis virus (LCMV) strain Armstrong, we show here that IRF9 limited early LCMV replication by regulating expression of interferon-stimulated genes and IFN-I and by controlling levels of IRF7, a transcription factor essential for IFN-I production. Infection of IRF9- or IFNAR-deficient mice led to a loss of early restriction of viral replication and impaired antiviral responses in dendritic cells, resulting in CD8+ T cell exhaustion and chronic infection. Differences in the antiviral activities of IRF9- and IFNAR-deficient mice and dendritic cells provided further evidence of IRF9-independent IFN-I signaling. Thus, our findings illustrate a CD8+ T cell-extrinsic function for IRF9, as a signaling factor downstream of IFNAR, in preventing overwhelming antigen exposure resulting in CD8+ T cell exhaustion and, ultimately, chronic infection. IMPORTANCE During early viral infection, overwhelming antigen exposure can cause functional exhaustion of CD8+ T cells and lead to chronic infection. Here we show that the transcription factor interferon regulatory factor 9 (IRF9) plays a decisive role in preventing CD8+ T cell exhaustion. Using acute infection of mice with LCMV strain Armstrong, we found that IRF9 limited early LCMV replication by regulating expression of interferon-stimulated genes and Irf7, encoding a transcription factor crucial for type I interferon (IFN-I) production, as well as by controlling the levels of IFN-I. Infection of IRF9-deficient mice led to a chronic infection that was accompanied by CD8+ T cell exhaustion due to defects extrinsic to T cells. Our findings illustrate an essential role for IRF9, as a mediator downstream of IFNAR, in preventing overwhelming antigen exposure causing CD8+ T cell exhaustion and leading to chronic viral infection.

scholarly journals Immune Exhaustion: Past Lessons and New Insights from Lymphocytic Choriomeningitis Virus

Viruses ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 156 ◽  
Author(s):  
Shannon Kahan ◽  
Allan Zajac
Keyword(s):  
T Cells ◽  
T Cell ◽  
Experimental System ◽  
Lymphocytic Choriomeningitis ◽  
Lymphocytic Choriomeningitis Virus ◽  
T Cell Exhaustion ◽  
Chronic Infections ◽  
Cell Exhaustion ◽  
Adult Mice ◽  
Track Record

Lymphocytic choriomeningitis virus (LCMV) is a paradigm-forming experimental system with a remarkable track record of contributing to the discovery of many of the fundamental concepts of modern immunology. The ability of LCMV to establish a chronic infection in immunocompetent adult mice was instrumental for identifying T cell exhaustion and this system has been invaluable for uncovering the complexity, regulators, and consequences of this state. These findings have been directly relevant for understanding why ineffective T cell responses commonly arise during many chronic infections including HIV and HCV, as well as during tumor outgrowth. The principal feature of exhausted T cells is the inability to elaborate the array of effector functions necessary to contain the underlying infection or tumor. Using LCMV to determine how to prevent and reverse T cell exhaustion has highlighted the potential of checkpoint blockade therapies, most notably PD-1 inhibition strategies, for improving cellular immunity under conditions of antigen persistence. Here, we discuss the discovery, properties, and regulators of exhausted T cells and highlight how LCMV has been at the forefront of advancing our understanding of these ineffective responses.

scholarly journals Lymphocytic choriomeningitis virus Clone 13 infection causes either persistence or acute death dependent on IFN-1, cytotoxic T lymphocytes (CTLs), and host genetics

2018 ◽  
Vol 115 (33) ◽  
pp. E7814-E7823 ◽  
Author(s):  
Michael B. A. Oldstone ◽  
Brian C. Ware ◽  
Lucy E. Horton ◽  
Megan J. Welch ◽  
Roberto Aiolfi ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Function ◽  
Lymphocytic Choriomeningitis ◽  
Lymphocytic Choriomeningitis Virus ◽  
T Cell Response ◽  
T Cell Exhaustion ◽  
Injury Death ◽  
Cell Exhaustion ◽  
Permeability Pulmonary Edema

Understanding of T cell exhaustion and successful therapy to restore T cell function was first described using Clone (Cl) 13 variant selected from the lymphocytic choriomeningitis virus (LCMV) Armstrong (ARM) 53b parental strain. T cell exhaustion plays a pivotal role in both persistent infections and cancers of mice and humans. C57BL/6, BALB, SWR/J, A/J, 129, C3H, and all but one collaborative cross (CC) mouse strain following Cl 13 infection have immunosuppressed T cell responses, high PD-1, and viral titers leading to persistent infection and normal life spans. In contrast, the profile of FVB/N, NZB, PL/J, SL/J, and CC NZO mice challenged with Cl 13 is a robust T cell response, high titers of virus, PD-1, and Lag3 markers on T cells. These mice all die 7 to 9 d after Cl 13 infection. Death is due to enhanced pulmonary endothelial vascular permeability, pulmonary edema, collapse of alveolar air spaces, and respiratory failure. Pathogenesis involves abundant levels of Cl 13 receptor alpha-dystroglycan on endothelial cells, with high viral replication in such cells leading to immunopathologic injury. Death is aborted by blockade of interferon-1 (IFN-1) signaling or deletion of CD8 T cells.

scholarly journals DHX37 Impacts Prognosis of Hepatocellular Carcinoma and Lung Adenocarcinoma through Immune Infiltration

2020 ◽  
Vol 2020 ◽  
pp. 1-20
Author(s):  
Yanni Xu ◽  
Qiongchao Jiang ◽  
Hejun Liu ◽  
Xiaoyun Xiao ◽  
Dinghong Yang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
T Cell ◽  
Lung Adenocarcinoma ◽  
Immune Tolerance ◽  
Prognostic Value ◽  
Complex Function ◽  
T Cell Exhaustion ◽  
Rna Helicases ◽  
Cell Exhaustion

Background. RNA helicases have various essential functions in basically all aspects of RNA metabolism, not only unwinding RNA but also disturbing the interaction of RNA with proteins. Recently, RNA helicases have been considered potential targets in cancers. So far, there has been no detailed investigation of the biological functions of RNA helicase DHX37 in cancers. Objective. We aim to identify the prognostic value of DHX37 associated with tumor microenvironments in cancers. Methods. DHX37 expression was examined via the Oncomine database and Tumor Immune Estimation Resource (TIMER). We explored the prognostic role of DHX37 in cancers across various databases. Coexpression genes, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), and fundamental regulators were performed via LinkedOmics. Confirming the prognostic value of DHX37 in liver hepatocellular carcinoma (LIHC) and lung adenocarcinoma (LUAD), we explored the role of DHX37 in infiltrated lymphocytes in cancers using the Gene Expression Profiling Interactive Analysis (GEPIA) and TIMER databases. Results. Through GO and KEGG analyses, expression of DHX37 was also correlated with complex function-specific networks involving the ribosome and RNA metabolic signaling pathways. In LIHC and LUAD, DHX37 expression showed significant positive correlations with markers of Tregs, myeloid-derived suppressor cells (MDSCs), and T cell exhaustion, contributing to immune tolerance. Conclusion. These results indicate that DHX37 can serve as a prognostic biomarker in LIHC and LUAD while having an important role in immune tolerance by activating the function of Tregs, MDSC, and T cell exhaustion.

scholarly journals VitaminD3 Regulates T Cell Immune Responses in Allergen and Rhinovirus Induced Asthma

2021 ◽  
Author(s):  
Susetta Finotto ◽  
Patricia Haag ◽  
Darja Andreev ◽  
Nina Li ◽  
Alexander Kiefer ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Murine Model ◽  
Peripheral Blood ◽  
Serum Levels ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Asthmatic Children ◽  
Rhinovirus Infection

Abstract Background: Serum 25(OH)-Vitamin D3 (VitD3) deficiency during infancy has been associated with asthma. The potential therapeutic role of VitD3 given in the airways and its interference with the allergen and Rhinovirus was the objective of this study. Methods: In two cohorts of children with and without asthma, serum levels of the C-reactive protein (CRP) were correlated to Serum VitD3 and in peripheral blood T cell inhibitor marker Programmed cell death protein 1 (PD1) mRNA was analyzed. In a murine model, VitD3 was given intranasally in vivo and in vitro to lung cells with allergen and Rhinovirus. Results: In the cohorts of pre-school age children without (control) asthma, CRP and VitD3 levels inversely correlated. In preschool asthmatic children that did not receive VitD3 supplementation as infant had more episode of asthma exacerbation associated with high CRP serum level. In peripheral blood cells from control but not asthmatic children with higher serum levels of VitD3 had lower PD1 mRNA levels. In murine model, OVA intranasal challenge induced Innate Lymphoid Cells type 2 (ILC2)-associated markers and Eosinophils in BALF and VitD3 inhibited lung inflammation and ILC2 markers. Furthermore, VitD3 given intranasally, induced CD4+T cells and reduced PD1, T regulatory cells in the lung. Similarly, VitD3 had a suppressive role on CD4+PD1+ T cells involved in T cell exhaustion in the airways in the absence of ST2 after Rhinovirus infection. Conclusion: These data support an inhibitory role of VitD3 on T cell exhaustion after allergen and rhinovirus infection that is relevant for pediatric asthma.

O032 Timing and magnitude of Type I interferon responses by distinct viral sensors impact CD8 T cell exhaustion and chronic infection

Cytokine ◽  
2012 ◽  
Vol 59 (3) ◽  
pp. 512
Author(s):  
Y. Wang ◽  
M. Swiecki ◽  
M. Cella ◽  
G. Alber ◽  
R.D. Schreiber ◽  
...  
Keyword(s):  
T Cell ◽  
Chronic Infection ◽  
Type I Interferon ◽  
Cd8 T Cell ◽  
Type I ◽  
T Cell Exhaustion ◽  
Cell Exhaustion ◽  
Interferon Responses
Sign in / Sign up

Export Citation Format

Share Document