scholarly journals HIV Blocks Interferon Induction in Human Dendritic Cells and Macrophages by Dysregulation of TBK1

2015 ◽  
Vol 89 (13) ◽  
pp. 6575-6584 ◽  
Author(s):  
Andrew N. Harman ◽  
Najla Nasr ◽  
Alexandra Feetham ◽  
Ani Galoyan ◽  
Abdullateef A. Alshehri ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Signaling Pathway ◽  
Sendai Virus ◽  
Type I Interferons ◽  
Target Cells ◽  
Type I ◽  
Accessory Proteins ◽  
Principal Mechanism ◽  
Interferon Induction ◽  
Hiv 1

ABSTRACTDendritic cells (DCs) and macrophages are present in the tissues of the anogenital tract, where HIV-1 transmission occurs in almost all cases. These cells are both target cells for HIV-1 and represent the first opportunity for the virus to interfere with innate recognition. Previously we have shown that both cell types fail to produce type I interferons (IFNs) in response to HIV-1 but that, unlike T cells, the virus does not block IFN induction by targeting IFN regulatory factor 3 (IRF3) for cellular degradation. Thus, either HIV-1 inhibits IFN induction by an alternate mechanism or, less likely, these cells fail to sense HIV-1. Here we show that HIV-1 (but not herpes simplex virus 2 [HSV-2] or Sendai virus)-exposed DCs and macrophages fail to induce the expression of all known type I and III IFN genes. These cells do sense the virus, and pattern recognition receptor (PRR)-induced signaling pathways are triggered. The precise stage in the IFN-inducing signaling pathway that HIV-1 targets to block IFN induction was identified; phosphorylation but not K63 polyubiquitination of TANK-binding kinase 1 (TBK1) was completely inhibited. Two HIV-1 accessory proteins, Vpr and Vif, were shown to bind to TBK1, and their individual deletion partly restored IFN-β expression. Thus, the inhibition of TBK1 autophosphorylation by binding of these proteins appears to be the principal mechanism by which HIV-1 blocks type I and III IFN induction in myeloid cells.IMPORTANCEDendritic cells (DCs) and macrophages are key HIV target cells. Therefore, definition of how HIV impairs innate immune responses to initially establish infection is essential to design preventative interventions, especially by restoring initial interferon production. Here we demonstrate how HIV-1 blocks interferon induction by inhibiting the function of a key kinase in the interferon signaling pathway, TBK1, via two different viral accessory proteins. Other viral proteins have been shown to target the general effects of TBK1, but this precise targeting between ubiquitination and phosphorylation of TBK1 is novel.

PLASMACYTOID DENDRITIC CELLS FUNCTION IN HIV INFECTION

2008 ◽  
Vol 31 (4) ◽  
pp. 13
Author(s):  
Martin Hyrcza ◽  
Mario Ostrowski ◽  
Sandy Der
Keyword(s):  
Dendritic Cells ◽  
Influenza Virus ◽  
Hiv Infection ◽  
Gene Transcription ◽  
Sendai Virus ◽  
Plasmacytoid Dendritic Cells ◽  
Type I Interferons ◽  
Interferon Response ◽  
Type I ◽  
Type I Ifn

Plasmacytoid dendritic cells (pDCs) are innate immune cells able to produce large quantities of type I interferons (IFN) when activated. Human immunodeficiency virus (HIV)-infected patients show generalized immune dysfunction characterized in part by chronic interferon response. In this study we investigated the role of dendritic cells inactivating and maintaining this response. Specifically we compared the IFN geneactivity in pDCs in response to several viruses and TLR agonists. We hypothesized that 1) the pattern of IFN gene transcription would differ in pDCs treated with HIV than with other agents, and 2) that pDCs from patients from different stages of disease would respond differently to the stimulations. To test these hypotheses, we obtained pDCs from 15 HIV-infected and uninfected individuals and treated freshly isolated pDCs with either HIV (BAL strain), influenza virus (A/PR/8/34), Sendai virus (Cantell strain), TLR7 agonist(imiquimod), or TLR9 agonist (CpG-ODN) for 6h. Type I IFN gene transcription was monitored by real time qPCRfor IFNA1, A2, A5, A6, A8,A17, B1, and E1, and cytokine levels were assayed by Cytometric Bead Arrays forTNF?, IL6, IL8, IL10, IL1?, and IL12p70. pDC function as determined by these two assays showed no difference between HIV-infected and uninfected patients or between patients with early or chronic infection. Specifically, HIV did notinduce type I IFN gene expression, whereas influenza virus, Sendai virus and imiquimod did. Similarly, HIV failed to induce any cytokine release from pDCs in contrast to influenza virus, Sendai virus and imiquimod, which stimulatedrelease of TNF?, IL6, or IL8. Together these results suggest that the reaction of pDCs to HIV virus is quantitatively different from the response to agents such as virus, Sendai virus, and imiquimod. In addition, pDCs from HIV-infected persons have responses similar to pDCs from uninfected donors, suggesting, that the DC function may not be affected by HIV infection.

scholarly journals cGAS/STING/TBK1/IRF3 Signaling Pathway Activates BMDCs Maturation Following Mycobacterium bovis Infection

2019 ◽  
Vol 20 (4) ◽  
pp. 895 ◽  
Author(s):  
Qiang Li ◽  
Chunfa Liu ◽  
Ruichao Yue ◽  
Saeed El-Ashram ◽  
Jie Wang ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Signaling Pathway ◽  
Mycobacterium Bovis ◽  
New Drugs ◽  
Type I Interferons ◽  
Type I ◽  
Type I Ifn ◽  
Innate Immune Responses ◽  
Dependent Signal

Cyclic GMP-AMP synthase (cGAS) is an important cytosolic DNA sensor that plays a crucial role in triggering STING-dependent signal and inducing type I interferons (IFNs). cGAS is important for intracellular bacterial recognition and innate immune responses. However, the regulating effect of the cGAS pathway for bone marrow-derived dendritic cells (BMDCs) during Mycobacterium bovis (M. bovis) infection is still unknown. We hypothesized that the maturation and activation of BMDCs were modulated by the cGAS/STING/TBK1/IRF3 signaling pathway. In this study, we found that M. bovis promoted phenotypic maturation and functional activation of BMDCs via the cGAS signaling pathway, with the type I IFN and its receptor (IFNAR) contributing. Additionally, we showed that the type I IFN pathway promoted CD4+ T cells’ proliferation with BMDC during M. bovis infection. Meanwhile, the related cytokines increased the expression involved in this signaling pathway. These data highlight the mechanism of the cGAS and type I IFN pathway in regulating the maturation and activation of BMDCs, emphasizing the important role of this signaling pathway and BMDCs against M. bovis. This study provides new insight into the interaction between cGAS and dendritic cells (DCs), which could be considered in the development of new drugs and vaccines against tuberculosis.

scholarly journals HIV-1 infection of human macrophages directly induces viperin which inhibits viral production

Blood ◽  
2012 ◽  
Vol 120 (4) ◽  
pp. 778-788 ◽  
Author(s):  
Najla Nasr ◽  
Susan Maddocks ◽  
Stuart G. Turville ◽  
Andrew N. Harman ◽  
Natalie Woolger ◽  
...  
Keyword(s):  
T Cells ◽  
Nuclear Translocation ◽  
Target Cells ◽  
Type I ◽  
Viral Production ◽  
Protein Prenylation ◽  
Interferon Stimulated Genes ◽  
Interferon Induction ◽  
Adenosyl Methionine ◽  
Hiv 1

AbstractMacrophages are key target cells for HIV-1. HIV-1BaL induced a subset of interferon-stimulated genes in monocyte-derived macrophages (MDMs), which differed from that in monocyte-derived dendritic cells and CD4 T cells, without inducing any interferons. Inhibition of type I interferon induction was mediated by HIV-1 inhibition of interferon-regulated factor (IRF3) nuclear translocation. In MDMs, viperin was the most up-regulated interferon-stimulated genes, and it significantly inhibited HIV-1 production. HIV-1 infection disrupted lipid rafts via viperin induction and redistributed viperin to CD81 compartments, the site of HIV-1 egress by budding in MDMs. Exogenous farnesol, which enhances membrane protein prenylation, reversed viperin-mediated inhibition of HIV-1 production. Mutagenesis analysis in transfected cell lines showed that the internal S-adenosyl methionine domains of viperin were essential for its antiviral activity. Thus viperin may contribute to persistent noncytopathic HIV-1 infection of macrophages and possibly to biologic differences with HIV-1–infected T cells.

scholarly journals HIV-1 Vpr Degrades TET2 to Suppress IRF7 and Interferon Expression in Plasmacytoid Dendritic Cells

2019 ◽  
Author(s):  
Qi Wang ◽  
Li-Chung Tsao ◽  
Lei Lv ◽  
Yanping Xu ◽  
Liang Cheng ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Viral Infections ◽  
Constitutive Expression ◽  
Plasmacytoid Dendritic Cells ◽  
Type I Interferons ◽  
Type I ◽  
Restriction Factors ◽  
Host Restriction ◽  
Host Restriction Factors ◽  
Hiv 1

AbstractPlasmacytoid dendritic cells (pDCs) are the major source of type I interferons (IFN-I) in rapid response to viral infections, with constitutive expression of interferon regulatory factor 7 (IRF7). HIV-1 expresses several accessory proteins to counteract specific IFN-induced host restriction factors. As one abundant virion-associated protein, HIV-1 Vpr remains enigmatic in enhancing HIV-1 infection via unclear mechanisms. Here we report that Vpr impaired IFN-I induction in pDCs to enhance HIV-1 replication in CD4+ T cells. Blockade of IFN-I signaling abrogated the effect of Vpr on HIV-1 replication. Virion-associated Vpr suppressed IFN-I induction in pDC by TLR7 agonists. Modulation of IFN-I induction by Vpr was genetically dependent on its activity of TET2 degradation. We further demonstrate that Vpr-mediated TET2 degradation reduced expression of IRF7 in pDCs. Finally, degradation of TET2 in pDCs by Vpr reduced the demethylation level of the IRF7 promoter via CXXC5-dependent recruitment. We conclude that HIV-1 Vpr functions to promote HIV-1 replication by suppressing TET2-dependent IRF7 expression and IFN-I induction in pDCs. The Vpr-TET2-IRF7 axis provides a novel therapeutic target to control HIV-1 infection.

Differential expression of type I interferon genes in plasmacytoid dendritic cells from HIV-infected patientss

2007 ◽  
Vol 30 (4) ◽  
pp. 84
Author(s):  
Martin D. Hyrcza ◽  
Sandy S. Der ◽  
Mario Ostrowski
Keyword(s):  
Dendritic Cells ◽  
Sendai Virus ◽  
Plasmacytoid Dendritic Cells ◽  
Type I Interferons ◽  
Interferon Response ◽  
Type I ◽  
Cpg Dna ◽  
Ifn Alpha ◽  
Hiv Virus ◽  
Peripheral T Cells

Background: Plasmacytoid dendritic cells (pDCs) are the most potent producers of type I interferons (IFN). Human genome contains thirteen IFN alpha genes and one IFN beta gene. Research in mice suggests that different IFNs are induced by different stimuli, but whether this is true in human cells is unknown. Patients with HIV-1 infection show chronic interferon response in peripheral T cells, which caused us to analyze the induction of the IFN alpha genes in their dendritic cells. Methods: Uninfected, acutely infected and long-term non-progressive donors were leukopheresed, following which pDCs were isolated by negative depletion. The dendritic cells were then treated for with one of the following: influenza virus, sendai virus, HIV virus, CpG DNA, imiquimod, or media alone, and the cells’ RNA was analysed by real time qPCR for changes in the RNA levels of four IFN alpha genes: α1, α2, α7, α8, as well as IFN beta. Results: Final results were not available at the time of abstract deposition.

scholarly journals Human plasmacytoid dendritic cells are equipped with antigen-presenting and tumoricidal capacities

Blood ◽  
2012 ◽  
Vol 120 (19) ◽  
pp. 3936-3944 ◽  
Author(s):  
Jurjen Tel ◽  
Evelien L. Smits ◽  
Sébastien Anguille ◽  
Rubin N. Joshi ◽  
Carl G. Figdor ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Viral Infections ◽  
Cell Subset ◽  
Plasmacytoid Dendritic Cells ◽  
Type I Interferons ◽  
Human Interferon ◽  
Target Cells ◽  
Type I ◽  
Dendritic Cell Subset ◽  
Antigen Presenting

Abstract Human plasmacytoid dendritic cells (pDCs) represent a highly specialized naturally occurring dendritic-cell subset and are the main producers of type I interferons (IFNs) in response to viral infections. We show that human pDCs activated by the preventive vaccine FSME specifically up-regulate CD56 on their surface, a marker that was thought to be specific for NK cells and associated with cytolytic effector functions. We observed that FSME-activated pDCs specifically lysed NK target cells and expressed cytotoxic molecules, such as tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and granzyme B. Elevated levels of these molecules coincided with the expression of CD56, indicative for skewing human pDCs toward an interferon-producing killer DC subset. Detailed phenotypical and functional analysis revealed that pDCs attained a mature phenotype, secreted proinflammatory cytokines, and had the capacity to present antigens and stimulate T cells. Here, we report on the generation of CD56+ human interferon producing killer pDCs with the capacity to present antigens. These findings aid in deciphering the role for pDCs in antitumor immunity and present a promising prospect of developing antitumor therapy using pDCs.

scholarly journals Type I Interferon Induction and Exhaustion during Viral Infection: Plasmacytoid Dendritic Cells and Emerging COVID-19 Findings

Viruses ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1839
Author(s):  
Trever T. Greene ◽  
Elina I. Zuniga
Keyword(s):  
Dendritic Cells ◽  
Viral Infection ◽  
Opportunistic Infections ◽  
Type I Interferon ◽  
Type I Interferons ◽  
Type I ◽  
Interferon Induction ◽  
Infection Models ◽  
Ongoing Infection ◽  
Increased Susceptibility

Type I Interferons (IFN-I) are a family of potent antiviral cytokines that act through the direct restriction of viral replication and by enhancing antiviral immunity. However, these powerful cytokines are a caged lion, as excessive and sustained IFN-I production can drive immunopathology during infection, and aberrant IFN-I production is a feature of several types of autoimmunity. As specialized producers of IFN-I plasmacytoid (p), dendritic cells (DCs) can secrete superb quantities and a wide breadth of IFN-I isoforms immediately after infection or stimulation, and are the focus of this review. Notably, a few days after viral infection pDCs tune down their capacity for IFN-I production, producing less cytokines in response to both the ongoing infection and unrelated secondary stimulations. This process, hereby referred to as “pDC exhaustion”, favors viral persistence and associates with reduced innate responses and increased susceptibility to secondary opportunistic infections. On the other hand, pDC exhaustion may be a compromise to avoid IFN-I driven immunopathology. In this review we reflect on the mechanisms that initially induce IFN-I and subsequently silence their production by pDCs during a viral infection. While these processes have been long studied across numerous viral infection models, the 2019 coronavirus disease (COVID-19) pandemic has brought their discussion back to the fore, and so we also discuss emerging results related to pDC-IFN-I production in the context of COVID-19.

scholarly journals TRIM22. A Multitasking Antiviral Factor

Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1864
Author(s):  
Isabel Pagani ◽  
Guido Poli ◽  
Elisa Vicenzi
Keyword(s):  
Protein Interactions ◽  
Influenza A ◽  
Direct Interaction ◽  
Type I Interferons ◽  
Viral Gene ◽  
Target Cells ◽  
Type I ◽  
Protein Protein Interactions ◽  
Viral Genomes ◽  
Dna And Rna

Viral invasion of target cells triggers an immediate intracellular host defense system aimed at preventing further propagation of the virus. Viral genomes or early products of viral replication are sensed by a number of pattern recognition receptors, leading to the synthesis and production of type I interferons (IFNs) that, in turn, activate a cascade of IFN-stimulated genes (ISGs) with antiviral functions. Among these, several members of the tripartite motif (TRIM) family are antiviral executors. This article will focus, in particular, on TRIM22 as an example of a multitarget antiviral member of the TRIM family. The antiviral activities of TRIM22 against different DNA and RNA viruses, particularly human immunodeficiency virus type 1 (HIV-1) and influenza A virus (IAV), will be discussed. TRIM22 restriction of virus replication can involve either direct interaction of TRIM22 E3 ubiquitin ligase activity with viral proteins, or indirect protein–protein interactions resulting in control of viral gene transcription, but also epigenetic effects exerted at the chromatin level.

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