Human cytomegalovirus blocks canonical TGFβ signaling during lytic infection to limit induction of type I interferons

Human cytomegalovirus (HCMV) microRNAs (miRNAs) significantly rewire host signaling pathways to support the viral lifecycle and regulate host cell responses. Here we show that SMAD3 expression is regulated by HCMV miR-UL22A and contributes to the IRF7-mediated induction of type I IFNs and IFN-stimulated genes (ISGs) in human fibroblasts. Addition of exogenous TGFβ interferes with the replication of a miR-UL22A mutant virus in a SMAD3-dependent manner in wild type fibroblasts, but not in cells lacking IRF7, indicating that downregulation of SMAD3 expression to limit IFN induction is important for efficient lytic replication. These findings uncover a novel interplay between SMAD3 and innate immunity during HCMV infection and highlight the role of viral miRNAs in modulating these responses.

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Human cytomegalovirus blocks canonical TGFβ signaling during lytic infection to limit induction of type I interferons

10.1101/2021.02.16.431411 ◽

2021 ◽

Author(s):

Andrew H. Pham ◽

Jennifer Mitchell ◽

Sara Botto ◽

Kara M. Pryke ◽

Victor R. Defilippis ◽

...

Keyword(s):

Human Cytomegalovirus ◽

Hcmv Infection ◽

Human Fibroblasts ◽

Lytic Replication ◽

Mutant Virus ◽

Type I Interferons ◽

Type I ◽

Dependent Manner ◽

Tgfβ Receptor ◽

Smad3 Expression

AbstractHuman cytomegalovirus (HCMV) microRNAs (miRNAs) significantly rewire host signaling pathways to support the viral lifecycle and regulate host cell responses. Here we show that SMAD3 expression is regulated by HCMV miR-UL22A and contributes to the IRF7-mediated induction of type I IFNs and IFN-stimulated genes (ISGs) in human fibroblasts. Addition of exogenous TGFβ interferes with the replication of a miR-UL22A mutant virus in a SMAD3-dependent manner in wild type fibroblasts, but not in cells lacking IRF7, indicating that downregulation of SMAD3 expression to limit IFN induction is important for efficient lytic replication. These findings uncover a novel interplay between SMAD3 and innate immunity during HCMV infection and highlight the role of viral miRNAs in modulating these responses.Author SummaryCells trigger the interferon (IFN) response to induce the expression of cellular genes that limit virus replication. In turn, viruses have evolved numerous countermeasures to avoid the effects of IFN signaling. Using a microRNA (miRNA) mutant virus we have uncovered a novel means of regulating the IFN response during human cytomegalovirus (HCMV) infection. Lytic HCMV infection induces the production of TGFβ, which binds to the TGFβ receptor and activates the receptor-associated SMAD SMAD3. SMAD3, together with IRF7, induces the expression of IFNβ and downstream IFN-stimulated genes in human fibroblasts. To counteract this, HCMV miR-UL22A, along with other HCMV gene products, directly targets SMAD3 for downregulation. Infection of fibroblasts with a miR-UL22A mutant virus results in enhanced type I IFN production in a SMAD3-dependent manner and the virus is impaired for growth in the presence of TGFβ, but only when both SMAD3 and IRF7 are present, highlighting the unique interaction between TGFβ and innate immune signaling.

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Interferon-Independent Upregulation of Interferon-Stimulated Genes during Human Cytomegalovirus Infection is Dependent on IRF3 Expression

Viruses ◽

10.3390/v11030246 ◽

2019 ◽

Vol 11 (3) ◽

pp. 246 ◽

Cited By ~ 26

Author(s):

Caroline Ashley ◽

Allison Abendroth ◽

Brian McSharry ◽

Barry Slobedman

Keyword(s):

Human Cytomegalovirus ◽

Hcmv Infection ◽

Human Fibroblasts ◽

Janus Kinase ◽

Type I Interferons ◽

Type I ◽

Type I Ifn ◽

Interferon Stimulated Genes ◽

Stat Signaling ◽

Isg15 Expression

The antiviral activity of type I interferons (IFNs) is primarily mediated by interferon-stimulated genes (ISGs). Induction of ISG transcription is achieved when type I IFNs bind to their cognate receptor and activate the Janus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) signaling pathways. Recently it has become clear that a number of viruses are capable of directly upregulating a subset of ISGs in the absence of type I IFN production. Using cells engineered to block either the response to, or production of type I IFN, the regulation of IFN-independent ISGs was examined in the context of human cytomegalovirus (HCMV) infection. Several ISGs, including IFIT1, IFIT2, IFIT3, Mx1, Mx2, CXCL10 and ISG15 were found to be upregulated transcriptionally following HCMV infection independently of type I IFN-initiated JAK-STAT signaling, but dependent on intact IRF3 signaling. ISG15 protein regulation mirrored that of its transcript with IFNβ neutralization failing to completely inhibit ISG15 expression post HCMV infection. In addition, no detectable ISG15 protein expression was observed following HCMV infection in IRF3 knockdown CRISPR/Cas-9 clones indicating that IFN-independent control of ISG expression during HCMV infection of human fibroblasts is absolutely dependent on IRF3 expression.

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DEF Cell-Derived Exosomal miR-148a-5p Promotes DTMUV Replication by Negative Regulating TLR3 Expression

Viruses ◽

10.3390/v12010094 ◽

2020 ◽

Vol 12 (1) ◽

pp. 94 ◽

Cited By ~ 3

Author(s):

Hongyan Guo ◽

Anchun Cheng ◽

Xingcui Zhang ◽

YuHong Pan ◽

Mingshu Wang ◽

...

Keyword(s):

Innate Immunity ◽

Viral Infections ◽

Membrane Vesicles ◽

Type I Interferons ◽

Inflammatory Factors ◽

Economic Losses ◽

Type I ◽

Dependent Manner ◽

Replication Process ◽

Type I Ifns

Duck tembusu virus (DTMUV) is a single-stranded, positive-polarity RNA flavivirus that has caused considerable economic losses in China in recent years. Innate immunity represents the first line of defense against invading pathogens and serves as an important role in resisting viral infections. In this study, we found that the infection of ducks by DTMUV triggers Toll-like receptors (TLRs) and (RIG-I)-like receptors (RLRs) signaling pathways and inducing abundant of pro-inflammatory factors and type I interferons (IFNs), in which melanoma differentiation-associated gene 5 (MDA5) and Toll-like receptor 3 (TLR3) play important immunity roles, they can inhibit the replication process of DTMUV via inducing type I IFNs. Moreover, we demonstrated that type I IFNs can inhibit the DTMUV replication process in a time- and dose-dependent manner. Exosomes are small membrane vesicles that have important roles in intercellular communication. MicroRNAs (miRNAs) are small non-coding RNAs that can modulate gene expression and are common substances in exosomes. In our experiment, we successfully isolated DEF cells derived exosome for the first time and explored its function. Firstly, we found the expression of miR-148a-5p is significantly decreased following DTMUV infect. Then we found miR-148a-5p can target TLR3 and down-regulate the expression of TLR3, serving as a negative factor in innate immunity. Unfortunately, we cannot find miRNAs with different expression changes that can target MDA5. Lastly, our experimental results showed that TLR3 was one of the causes of miR-148a-5p reduction, suggesting that the high level of TLR3 after DTMUV infect can both trigger innate immunity and suppress miR-148a-5p to resist DTMUV.

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AB0042 CYTOKINE NETWORK ELUCIDATED BY THE QUANTIFICATION OF MULTIPLE CYTOKINES IN THE SERUM SEQUENTIALLY SAMPLED FROM RA PATIENTS WHO WERE TREATED WITH BIOLOGIC DMARDS

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2020-eular.5109 ◽

2020 ◽

Vol 79 (Suppl 1) ◽

pp. 1323.2-1324

Author(s):

K. Sato ◽

S. Mamada ◽

C. Hayashi ◽

T. Nagashima ◽

S. Minota

Keyword(s):

Bone Erosion ◽

Feedback System ◽

Serum Levels ◽

Type I Interferons ◽

Type I ◽

Serum Samples ◽

Cytokine Network ◽

Biologic Dmards ◽

Type I Ifns ◽

Before And After

Background:Biologic disease modifying anti-rheumatic drugs (DMARDs) have demonstrated that proinflammatory cytokines such as interleukin (IL-) 6 and tumor necrosis factor (TNF) play important roles in the pathogenesis of rheumatoid arthritis (RA). Other cytokines, such as type I interferons (IFNs), are also implicated in its pathogenesis (ref 1). However, the complete picture of the cytokine network involved in RA remains to be elucidated.Objectives:By quantifying sets of cytokines in the serum of RA patients before and after treatment with various biologic DMARDs, we sought to determine the effects of drugs on (A) type I IFNs, (B) soluble IL-6 receptors, and (C) other cytokines.Methods:52 patients with RA were treated with various biologic DMARDs (tocilizumab (TOC): 16, abatacept (ABT): 15, and TNF inhibitors (TNFi): 21). Serum samples were obtained (1) before, (2) approximately 4 weeks after (3) and approximately 12 weeks after the initiation of treatment. A suspension bead-array system was used for analysis; Bio-Plex Human Cytokine 17-plex Assay kits and Express Custom Panels (Bio-Rad), including IFN-β, IFN-α2, soluble IL-6 receptor α (sIL6Rα) and gp130 were used.Results:(1) As expected, the disease activity score 28-joiny count (DAS28) using the erythrocyte sedimentation rate (ESR) significantly decreased in all three groups (TOC, ABT and TNFi) by 12 weeks.(2) IFN-α2 was barely detected in the serum samples. IFN-β seemed to increase slightly in the ABT group, but the increase was not statistically significant.(3) The levels of sIL6Rα did not change substantially. Those of gp130 decreased slightly but significantly in the TOC group by 12 weeks.(4) The levels of IL-6 decreased significantly in the ABT group by 12 weeks. Those in the TNFi group decreased significantly at 4 weeks but not 12 weeks (Fig. 1A).(5) The levels of IL-7 decreased significantly only in the TOC group (Fig. 1B).Conclusion:(1) The biologic DMARDs tested in this study did not significantly affect the serum levels of type I IFNs in this study.(2) The decrease in gp130 in the TOC group may imply that gp130 is induced by IL-6, although whether this level of decrease has physiological significance is open to question.(3) Serum IL-6 was significantly decreased in the TNFi group at 4 weeks but not 12 weeks. TNF has been reported to induce IL-6 (ref 2), but negative feedback loop(s) may be present. Such a feedback system might make the discontinuation of TNFi difficult, even if patients are in remission.(4) IL-7 may be a target of IL-6. A higher level of IL-7 has been reported to be present in the joints of RA patients compared with osteoarthrosis and it is a cytokine implicated in the differentiation of osteoclasts (ref 3). This may partly explain the effect of TOC on preventing bone erosion in RA.References:[1]Ann Rheum Dis. 2007; 66: 1008–14[2]Rheumatology 2007; 46: 920-6[3]Rheumatology 2008; 47: 753-9Acknowledgments:We thank all the members of the Division of Rheumatology and Clinical Immunology, Department of Medicine, Jichi Medical University. We are also grateful to the patients involved in this study.Disclosure of Interests:Kojiro Sato Grant/research support from: Abbie, Pfizer, Chugai, Astellas, Mitsubishi-Tanabe, Ono, Takeda, Sachiko Mamada: None declared, Chiyomi Hayashi: None declared, Takao Nagashima: None declared, Seiji Minota: None declared

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A Kaposi's Sarcoma-Associated Herpesvirus Protein That Forms Inhibitory Complexes with Type I Interferon Receptor Subunits, Jak and STAT Proteins, and Blocks Interferon-Mediated Signal Transduction

Journal of Virology ◽

10.1128/jvi.02516-08 ◽

2009 ◽

Vol 83 (10) ◽

pp. 5056-5066 ◽

Cited By ~ 42

Author(s):

Sabine A. Bisson ◽

Anne-Laure Page ◽

Don Ganem

Keyword(s):

Kaposi's Sarcoma ◽

Human Tumor ◽

Kaposi’S Sarcoma ◽

Lytic Replication ◽

Type I Interferons ◽

Type I ◽

Type I Ifn ◽

Reading Frame ◽

Kaposi's Sarcoma Associated Herpesvirus ◽

Kaposi’S Sarcoma Associated Herpesvirus

ABSTRACT Type I interferons (IFNs) are important mediators of innate antiviral defense and function by activating a signaling pathway through their cognate type I receptor (IFNAR). Here we report that lytic replication of Kaposi's sarcoma-associated herpesvirus (KSHV) efficiently blocks type I IFN signaling and that an important effector of this blockade is the viral protein RIF, the product of open reading frame 10. RIF blocks IFN signaling by formation of inhibitory complexes that contain IFNAR subunits, the Janus kinases Jak1 and Tyk2, and the STAT2 transcription factor. Activation of both Tyk2 and Jak1 is inhibited, and abnormal recruitment of STAT2 to IFNAR1 occurs despite the decrement in Tyk2 activity. As a result of these actions, phosphorylation of both STAT2 and STAT1 is impaired, with subsequent failure of ISGF3 accumulation in the nucleus. The presence in the viral genome of potent inhibitors of type I IFN signaling, along with several viral genes that block IFN induction, highlights the importance of the IFN pathway in the control of this human tumor virus infection.

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Activation of Stimulator of Interferon Genes (STING) and Sjögren Syndrome

Journal of Dental Research ◽

10.1177/0022034518760855 ◽

2018 ◽

Vol 97 (8) ◽

pp. 893-900 ◽

Cited By ~ 11

Author(s):

J. Papinska ◽

H. Bagavant ◽

G.B. Gmyrek ◽

M. Sroka ◽

S. Tummala ◽

...

Keyword(s):

Gene Expression ◽

Viral Infections ◽

Critical Role ◽

Autoimmune Disorder ◽

Sjögren Syndrome ◽

Lymphoid Cells ◽

Type I Interferons ◽

Sjogren Syndrome ◽

Type I ◽

Type I Ifns

Sjögren syndrome (SS), a chronic autoimmune disorder causing dry mouth, adversely affects the overall oral health in patients. Activation of innate immune responses and excessive production of type I interferons (IFNs) play a critical role in the pathogenesis of this disorder. Recognition of nucleic acids by cytosolic nucleic acid sensors is a major trigger for the induction of type I IFNs. Upon activation, cytosolic DNA sensors can interact with the stimulator of interferon genes (STING) protein, and activation of STING causes increased expression of type I IFNs. The role of STING activation in SS is not known. In this study, to investigate whether the cytosolic DNA sensing pathway influences SS development, female C57BL/6 mice were injected with a STING agonist, dimethylxanthenone-4-acetic acid (DMXAA). Salivary glands (SGs) were studied for gene expression and inflammatory cell infiltration. SG function was evaluated by measuring pilocarpine-induced salivation. Sera were analyzed for cytokines and autoantibodies. Primary SG cells were used to study the expression and activation of STING. Our data show that systemic DMXAA treatment rapidly induced the expression of Ifnb1, Il6, and Tnfa in the SGs, and these cytokines were also elevated in circulation. In contrast, increased Ifng gene expression was dominantly detected in the SGs. The type I innate lymphoid cells present within the SGs were the major source of IFN-γ, and their numbers increased significantly within 3 d of treatment. STING expression in SGs was mainly observed in ductal and interstitial cells. In primary SG cells, DMXAA activated STING and induced IFN-β production. The DMXAA-treated mice developed autoantibodies, sialoadenitis, and glandular hypofunction. Our study demonstrates that activation of the STING pathway holds the potential to initiate SS. Thus, apart from viral infections, conditions that cause cellular perturbations and accumulation of host DNA within the cytosol should also be considered as possible triggers for SS.

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Type I interferons act directly on nociceptors to produce pain sensitization: Implications for viral infection-induced pain

10.1101/2019.12.27.889568 ◽

2019 ◽

Author(s):

Paulino Barragan-Iglesias ◽

Úrzula Franco-Enzástiga ◽

Vivekanand Jeevakumar ◽

Andi Wangzhou ◽

Vinicio Granados-Soto ◽

...

Keyword(s):

Viral Infection ◽

Viral Infections ◽

Mrna Translation ◽

Type I Interferons ◽

Poly I:C ◽

Type I ◽

Drg Neurons ◽

Pain Hypersensitivity ◽

Type I Ifns ◽

Pain Sensitization

ABSTRACTOne of the first signs of viral infection is body-wide aches and pain. While this type of pain usually subsides, at the extreme, viral infections can induce painful neuropathies that can last for decades. Neither of these types of pain sensitization are well understood. A key part of the response to viral infection is production of interferons (IFNs), which then activate their specific receptors (IFNRs) resulting in downstream activation of cellular signaling and a variety of physiological responses. We sought to understand how type I IFNs (IFN-α and IFN-β) might act directly on nociceptors in the dorsal root ganglion (DRG) to cause pain sensitization. We demonstrate that type I IFNRs are expressed in small/medium DRG neurons and that their activation produces neuronal hyper-excitability and mechanical pain in mice. Type I IFNs stimulate JAK/STAT signaling in DRG neurons but this does not apparently result in PKR-eIF2α activation that normally induces an anti-viral response by limiting mRNA translation. Rather, type I interferons stimulate MNK-mediated eIF4E phosphorylation in DRG neurons to promote pain hypersensitivity. Endogenous release of type I IFNs with the double stranded RNA mimetic poly(I:C) likewise produces pain hypersensitivity that is blunted in mice lacking MNK-eIF4E signaling. Our findings reveal mechanisms through which type I IFNs cause nociceptor sensitization with implications for understanding how viral infections promote pain and can lead to neuropathies.SIGNIFICANCE STATEMENTIt is increasingly understood that pathogens interact with nociceptors to alert organisms to infection as well as to mount early host defenses. While specific mechanisms have been discovered for diverse bacteria and fungal pathogens, mechanisms engaged by viruses have remained elusive. Here we show that type 1 interferons, one of the first mediators produced by viral infection, act directly on nociceptors to produce pain sensitization. Type I interferons act via a specific signaling pathway (MNK-eIF4E signaling) that is known to produce nociceptor sensitization in inflammatory and neuropathic pain conditions. Our work reveals a mechanism through which viral infections cause heightened pain sensitivity

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Activation of Kaposi's Sarcoma-Associated Herpesvirus (Human Herpesvirus 8) Lytic Replication by Human Cytomegalovirus

Journal of Virology ◽

10.1128/jvi.75.3.1378-1386.2001 ◽

2001 ◽

Vol 75 (3) ◽

pp. 1378-1386 ◽

Cited By ~ 134

Author(s):

Jeffrey Vieira ◽

Patricia O'Hearn ◽

Louise Kimball ◽

Bala Chandran ◽

Lawrence Corey

Keyword(s):

Human Cytomegalovirus ◽

Kaposi's Sarcoma ◽

Human Fibroblasts ◽

Human Herpesvirus ◽

Kaposi’S Sarcoma ◽

Lytic Replication ◽

Lytic Cycle ◽

Nuclear Antigen ◽

Kaposi's Sarcoma Associated Herpesvirus ◽

Kaposi’S Sarcoma Associated Herpesvirus

ABSTRACT The majority of Kaposi's sarcoma-associated herpesvirus (KSHV)-infected cells identified in vivo contain latent KSHV, with lytic replication in only a few percent of cells, as is the case for the cells of Kaposi's sarcoma (KS) lesions. Factors that influence KSHV latent or lytic replication are not well defined. Because persons with KS are often immunosuppressed and susceptible to many infectious agents, including human cytomegalovirus (HCMV), we have investigated the potential for HCMV to influence the replication of KSHV. Important to this work was the construction of a recombinant KSHV, rKSHV.152, expressing the green fluorescent protein (GFP) andneo (conferring resistance to G418). The expression of GFP was a marker of KSHV infection in cells of both epithelial and endothelial origin. The rKSHV.152 virus was used to establish cells, including human fibroblasts (HF), containing only latent KSHV, as demonstrated by latency-associated nuclear antigen expression and Gardella gel analysis. HCMV infection of KSHV latently infected HF activated KSHV lytic replication with the production of infectious KSHV. Dual-color immunofluorescence detected both the KSHV lytic open reading frame 59 protein and the HCMV glycoprotein B in coinfected cells, and UV-inactivated HCMV did not activate the production of infectious KSHV-GFP. In addition, HCMV coinfection increased the production of KSHV from endothelial cells and activated lytic cycle gene expression in keratinocytes. These data demonstrate that HCMV can activate KSHV lytic replication and suggest that HCMV could influence KSHV pathogenesis.

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Adjuvant activity of type I interferons

Biological Chemistry ◽

10.1515/bc.2008.051 ◽

2008 ◽

Vol 389 (5) ◽

Cited By ~ 41

Author(s):

Michael G. Tovey ◽

Christophe Lallemand ◽

George Thyphronitis

Keyword(s):

Immune Response ◽

Antibody Response ◽

Antigen Presentation ◽

Response Characteristic ◽

Influenza Virus Vaccine ◽

Type I Interferons ◽

Type I ◽

Adjuvant Activity ◽

Virus Challenge ◽

Type I Ifns

AbstractType I interferons (IFNs) produced primarily by plasmacytoid dendritic cells (pDCs) as part of the innate immune response to infectious agents induce the maturation of myeloid DCs and enhance antigen presentation. Type I IFNs also enhance apoptosis of virus-infected cells, stimulate cross priming and enhanced presentation of viral peptides. Type I IFNs are powerful polyclonal B-cell activators that induce a strong primary humoral immune response characterized by isotype switching and protection against virus challenge. Type I IFNs stimulate an IgG2a antibody response characteristic of Th1 immunity when ad-mixed with influenza virus vaccine and injected intramuscurarly (i.m.) or administered intranasally. The adjuvant activity of type I IFNs has been shown to involve direct effects of IFN on B-cells, effects on T-cells, as well as effects on antigen presentation. Oromucosal administration of type I IFNs concomitantly with i.m. injection of vaccine alone can also enhance the antibody response to influenza vaccination by enhancing trafficking of antigen-presenting cells towards the site of vaccination. Recombinant IFNs are potent adjuvants that may find application in both parenterally and mucosally administered vaccines.

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The activation of bystander CD8+ T cells and their roles in viral infection

Experimental & Molecular Medicine ◽

10.1038/s12276-019-0316-1 ◽

2019 ◽

Vol 51 (12) ◽

pp. 1-9 ◽

Cited By ~ 12

Author(s):

Tae-Shin Kim ◽

Eui-Cheol Shin

Keyword(s):

T Cells ◽

Viral Infections ◽

Hepatitis A Virus ◽

Tissue Injury ◽

Strong Association ◽

Killer Cell ◽

Type I Interferons ◽

Type I ◽

Dependent Manner ◽

Bystander Activation

AbstractDuring viral infections, significant numbers of T cells are activated in a T cell receptor-independent and cytokine-dependent manner, a phenomenon referred to as “bystander activation.” Cytokines, including type I interferons, interleukin-18, and interleukin-15, are the most important factors that induce bystander activation of T cells, each of which plays a somewhat different role. Bystander T cells lack specificity for the pathogen, but can nevertheless impact the course of the immune response to the infection. For example, bystander-activated CD8+ T cells can participate in protective immunity by secreting cytokines, such as interferon-γ. They also mediate host injury by exerting cytotoxicity that is facilitated by natural killer cell-activating receptors, such as NKG2D, and cytolytic molecules, such as granzyme B. Interestingly, it has been recently reported that there is a strong association between the cytolytic function of bystander-activated CD8+ T cells and host tissue injury in patients with acute hepatitis A virus infection. The current review addresses the induction of bystander CD8+ T cells, their effector functions, and their potential roles in immunity to infection, immunopathology, and autoimmunity.

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