scholarly journals Intron-containing RNA from the HIV-1 provirus activates type I interferon and inflammatory cytokines

2017 ◽  
Author(s):  
Sean Matthew McCauley ◽  
Kyusik Kim ◽  
Anetta Nowosielska ◽  
Ann Dauphin ◽  
Leonid Yurkovetskiy ◽  
...  
Keyword(s):  
T Cells ◽  
Antiviral Therapy ◽  
Antiviral Drug ◽  
Cell Types ◽  
Innate Immune ◽  
Type I ◽  
Infected People ◽  
Innate Immune Signaling ◽  
Post Transcriptional Regulation ◽  
Hiv 1

ABSTRACTHIV-1-infected people who take drugs that suppress viremia to undetectable levels are protected from developing AIDS. Nonetheless, these individuals have chronic inflammation associated with heightened risk of cardiovascular pathology. HIV-1 establishes proviruses in long-lived CD4+memory T cells, and perhaps other cell types, that preclude elimination of the virus even after years of continuous antiviral therapy. Though the majority of proviruses that persist during antiviral therapy are defective for production of infectious virions, many are expressed, raising the possibility that the HIV-1provirus or its transcripts contribute to ongoing inflammation. Here we found that the HIV-1 provirus activated innate immune signaling in isolated dendritic cells, macrophages, and CD4+T cells. Immune activation required transcription from the HIV-1 provirus and expression of CRM1-dependent, Rev-dependent, RRE-containing, unspliced HIV-1 RNA. Ifrevwas providedin trans, all HIV-1 coding sequences were dispensable for activation except thosecis-acting sequences required for replication or splicing. These results indicate that the complex, post-transcriptional regulation intrinsic to HIV-1 RNA is detected by the innate immune system as a danger signal, and that drugs which disrupt HIV-1 transcription or HIV-1 RNA metabolism would add qualitative benefit to current antiviral drug regimens.

scholarly journals Interferon-Inducible CD169/Siglec1 Attenuates Anti-HIV-1 Effects of Alpha Interferon

2017 ◽  
Vol 91 (21) ◽  
Author(s):  
Hisashi Akiyama ◽  
Nora-Guadalupe Pina Ramirez ◽  
Gregory Gibson ◽  
Christopher Kline ◽  
Simon Watkins ◽  
...  
Keyword(s):  
T Cells ◽  
Immune Activation ◽  
Myeloid Cells ◽  
Cell Types ◽  
Productive Infection ◽  
Type I ◽  
Type I Ifn ◽  
Antiviral State ◽  
Hiv 1

ABSTRACT A hallmark of human immunodeficiency virus type 1 (HIV-1) infection in vivo is chronic immune activation concomitant with type I interferon (IFN) production. Although type I IFN induces an antiviral state in many cell types, HIV-1 can replicate in vivo via mechanisms that have remained unclear. We have recently identified a type I IFN-inducible protein, CD169, as the HIV-1 attachment factor on dendritic cells (DCs) that can mediate robust infection of CD4+ T cells in trans. Since CD169 expression on macrophages is also induced by type I IFN, we hypothesized that type I IFN-inducible CD169 could facilitate productive HIV-1 infection in myeloid cells in cis and CD4+ T cells in trans and thus offset antiviral effects of type I IFN. In support of this hypothesis, infection of HIV-1 or murine leukemia virus Env (MLV-Env)-pseudotyped HIV-1 particles was enhanced in IFN-α-treated THP-1 monocytoid cells, and this enhancement was primarily dependent on CD169-mediated enhancement at the virus entry step, a phenomenon phenocopied in HIV-1 infections of IFN-α-treated primary monocyte-derived macrophages (MDMs). Furthermore, expression of CD169, a marker of type I IFN-induced immune activation in vivo, was enhanced in lymph nodes from pigtailed macaques infected with simian immunodeficiency virus (SIV) carrying HIV-1 reverse transcriptase (RT-SHIV), compared to uninfected macaques, and interestingly, there was extensive colocalization of p27gag and CD169, suggesting productive infection of CD169+ myeloid cells in vivo. While cell-free HIV-1 infection of IFN-α-treated CD4+ T cells was robustly decreased, initiation of infection in trans via coculture with CD169+ IFN-α-treated DCs restored infection, suggesting that HIV-1 exploits CD169 in cis and in trans to attenuate a type I IFN-induced antiviral state. IMPORTANCE HIV-1 infection in humans causes immune activation characterized by elevated levels of proinflammatory cytokines, including type I interferons (IFN). Although type I IFN induces an antiviral state in many cell types in vitro, HIV-1 can replicate in vivo via mechanisms that have remained unclear. In this study, we tested the hypothesis that CD169, a type I IFN-inducible HIV-1 attachment factor, offsets antiviral effects of type I IFN. Infection of HIV-1 was rescued in IFN-α-treated myeloid cells via upregulation of CD169 and a subsequent increase in CD169-dependent virus entry. Furthermore, extensive colocalization of viral Gag and CD169 was observed in lymph nodes of infected pigtailed macaques, suggesting productive infection of CD169+ cells in vivo. Treatment of dendritic cell (DC)-T cell cocultures with IFN-α upregulated CD169 expression on DCs and rescued HIV-1 infection of CD4+ T cells in trans, suggesting that HIV-1 exploits CD169 to attenuate type I IFN-induced restrictions.

scholarly journals Human Immunodeficiency Virus Type 1 Mediates Global Disruption of Innate Antiviral Signaling and Immune Defenses within Infected Cells

2009 ◽  
Vol 83 (20) ◽  
pp. 10395-10405 ◽  
Author(s):  
Brian P. Doehle ◽  
Florian Hladik ◽  
John P. McNevin ◽  
M. Juliana McElrath ◽  
Michael Gale
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Virus Infection ◽  
Innate Immune ◽  
Immune Signaling ◽  
Innate Immune Signaling ◽  
Immunodeficiency Virus ◽  
Infected Cells ◽  
Hiv 1

ABSTRACT Interferon regulatory factor 3 (IRF-3) is essential for innate intracellular immune defenses that limit virus replication, but these defenses fail to suppress human immunodeficiency virus (HIV) infection, which can ultimately associate with opportunistic coinfections and the progression to AIDS. Here, we examined antiviral defenses in CD4+ cells during virus infection and coinfection, revealing that HIV type 1 (HIV-1) directs a global disruption of innate immune signaling and supports a coinfection model through suppression of IRF-3. T cells responded to paramyxovirus infection to activate IRF-3 and interferon-stimulated gene expression, but they failed to mount a response against HIV-1. The lack of response associated with a marked depletion of IRF-3 but not IRF-7 in HIV-1-infected cells, which supported robust viral replication, whereas ectopic expression of active IRF-3 suppressed HIV-1 infection. IRF-3 depletion was dependent on a productive HIV-1 replication cycle and caused the specific disruption of Toll-like receptor and RIG-I-like receptor innate immune signaling that rendered cells permissive to secondary virus infection. IRF-3 levels were reduced in vivo within CD4+ T cells from patients with acute HIV-1 infection but not from long-term nonprogressors. Our results indicate that viral suppression of IRF-3 promotes HIV-1 infection by disrupting IRF-3-dependent signaling pathways and innate antiviral defenses of the host cell. IRF-3 may direct an innate antiviral response that regulates HIV-1 replication and viral set point while governing susceptibility to opportunistic virus coinfections.

scholarly journals Interferon-inducible miR-128 modulates HIV-1 replication by targeting TNPO3 mRNA

2017 ◽  
Author(s):  
Aurore Bochnakian ◽  
Dimitrios G Zisoulis ◽  
Adam Idica ◽  
Anjie Zhen ◽  
Vineet N KewalRamani ◽  
...  
Keyword(s):  
T Cells ◽  
Nuclear Import ◽  
Cd4 T Cells ◽  
Jurkat Cells ◽  
Type I ◽  
Coding Region ◽  
Aids Pandemic ◽  
Mrna And Protein Expression ◽  
Dual Mechanism ◽  
Hiv 1

ABSTRACTThe HIV/AIDS pandemic remains an important threat to human health. We have recently demonstrated that a novel microRNA (miR-128) represses retrotransposon (LINE-1 or L1) by a dual mechanism, by directly targeting the coding region of the L1 RNA and by repressing a required nuclear import factor (TNPO1). We have further determined that miR-128 represses the expression of all three isoforms of TNPO proteins (transportins, TNPO1,-2 and TNPO3). Here, we establish that miR-128 also controls HIV-1 replication by repressing TNPO3. TNPO3 is well established to regulate HIV-1 nuclear import and viral replication. Here, we report that the type I interferon inducible miR-128 directly targets two sites in the TNPO3 mRNA, significantly down-regulating TNPO3 mRNA and protein expression levels. Manipulation of miR-128 levels in HIV target cell lines and in primary human CD4 T-cells by over-expression or knockdown showed that modulation of TNPO3 by miR-128 affects HIV-1 replication but not MLV infection. In addition, we found that miR-128 modulation of HIV-1 replication is reduced with TNPO3-independent HIV-1 virus and in cells depleted of CPSF6, suggesting that miR-128-indued TNPO3 repression is partly required for miR-128-induced inhibition of HIV-1 replication. Finally, challenging miR-modulated Jurkat cells or primary CD4 T-cells with wildtype, replication-competent HIV-1 shows that miR-128 significantly delays spreading infection. Thus, we have established a novel role of miR-128 in anti-viral defense in human cells, inhibiting HIV-1 replication partly by targeting TNPO3.

scholarly journals MAVS: A Two-Sided CARD Mediating Antiviral Innate Immune Signaling and Regulating Immune Homeostasis

2021 ◽  
Vol 12 ◽  
Author(s):  
Yunqiang Chen ◽  
Yuheng Shi ◽  
Jing Wu ◽  
Nan Qi
Keyword(s):  
Signal Transduction ◽  
Innate Immune ◽  
Immune Homeostasis ◽  
Type I ◽  
Interferon Signaling ◽  
Immune Signaling ◽  
Post Translational Modifications ◽  
Innate Immune Signaling ◽  
Mitochondrial Antiviral Signaling ◽  
Mitochondrial Antiviral Signaling Protein

Mitochondrial antiviral signaling protein (MAVS) functions as a “switch” in the immune signal transduction against most RNA viruses. Upon viral infection, MAVS forms prion-like aggregates by receiving the cytosolic RNA sensor retinoic acid-inducible gene I-activated signaling and further activates/switches on the type I interferon signaling. While under resting state, MAVS is prevented from spontaneously aggregating to switch off the signal transduction and maintain immune homeostasis. Due to the dual role in antiviral signal transduction and immune homeostasis, MAVS has emerged as the central regulation target by both viruses and hosts. Recently, researchers show increasing interest in viral evasion strategies and immune homeostasis regulations targeting MAVS, especially focusing on the post-translational modifications of MAVS, such as ubiquitination and phosphorylation. This review summarizes the regulations of MAVS in antiviral innate immune signaling transduction and immune homeostasis maintenance.

scholarly journals Selection following isolation of human immunodeficiency virus type 1 in peripheral blood mononuclear cells and herpesvirus saimiri-transformed T cells is comparable

2002 ◽  
Vol 83 (6) ◽  
pp. 1343-1352 ◽  
Author(s):  
Natalie N. Zheng ◽  
Cherelyn Vella ◽  
Philippa J. Easterbrook ◽  
Rod S. Daniels
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Peripheral Blood Mononuclear Cells ◽  
Mononuclear Cells ◽  
Cell Types ◽  
Herpesvirus Saimiri ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficiency Virus ◽  
Blood Mononuclear Cells ◽  
Hiv 1

In attempts to improve isolation rates and virus yields for human immunodeficiency virus (HIV), the use of herpesvirus saimiri-immortalized T cells (HVS T cells) has been investigated as an alternative to/improvement over peripheral blood mononuclear cells (PBMCs). Here we characterize isolates rescued, in the two cell types, from two asymptomatic, long-term non-progressing HIV-1-infected individuals. All rescued viruses replicated in PBMCs and HVS T cells only, displaying a non-syncytium inducing (NSI) phenotype, and using CCR5 as co-receptor. Furthemore, PBMC/HVS T cell virus pairs displayed similar neutralization profiles. Full-length, expression-competent env genes were rescued from all virus isolates and directly from the patient samples using proviral DNA and viral RNA as templates. Compared with the sequences retrieved directly from the patient samples, both cell types showed similar selection characteristics. Whilst the selections were distinct for individual patient samples, they shared a common characteristic in selecting for viruses with increased negative charge across the V2 domain of the viral glycoproteins. The latter was observed at the env gene sequencing level for three other patients whose HIV strains were isolated in PBMCs only. This further supports a common selection for viral sequences that display a macrophage-tropic/NSI phenotype and shows that HVS T cells are a viable alternative to PBMCs for HIV-1 isolation.

scholarly journals Longitudinal single-cell immune profiling revealed distinct innate immune response in asymptomatic COVID-19 patients

2020 ◽  
Author(s):  
Xiang-Na Zhao ◽  
Yue You ◽  
Guo-Lin Wang ◽  
Hui-Xia Gao ◽  
Xiao-Ming Cui ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Single Cell ◽  
Innate Immune Response ◽  
Clonal Expansion ◽  
Innate Immune ◽  
Type I ◽  
Severe Condition ◽  
Asymptomatic Patients

SUMMARYRecent studies have characterized the single-cell immune landscape of host immune response of coronavirus disease 2019 (COVID-19), specifically focus on the severe condition. However, the immune response in mild or even asymptomatic patients remains unclear. Here, we performed longitudinal single-cell transcriptome sequencing and T cell/B cell receptor sequencing on 3 healthy donors and 10 COVID-19 patients with asymptomatic, moderate, and severe conditions. We found asymptomatic patients displayed distinct innate immune responses, including increased CD56briCD16− NK subset, which was nearly missing in severe condition and enrichment of a new Th2-like cell type/state expressing a ciliated cell marker. Unlike that in moderate condition, asymptomatic patients lacked clonal expansion of effector CD8+ T cells but had a robust effector CD4+ T cell clonal expansion, coincide with previously detected SARS-CoV-2-reactive CD4+ T cells in unexposed individuals. Moreover, NK and effector T cells in asymptomatic patients have upregulated cytokine related genes, such as IFNG and XCL2. Our data suggest early innate immune response and type I immunity may contribute to the asymptomatic phenotype in COVID-19 disease, which could in turn deepen our understanding of severe COVID-19 and guide early prediction and therapeutics.

Structure and functions of T-cell immunoglobulin-domain and mucin- domain protein 3 in cancer

2021 ◽  
Vol 28 ◽  
Author(s):  
Xinjie Lu
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cancer Immunotherapy ◽  
Intracellular Signaling ◽  
Checkpoint Inhibitors ◽  
Cell Types ◽  
Structural Features ◽  
Type I ◽  
Potential Biomarker ◽  
Tim Proteins

Background: T-cell immunoglobulin (Ig)-domain and mucin-domain (TIM) proteins represent a family of receptors expressed on T-cells that play essential cellular immunity roles. The TIM proteins span across the membrane belonging to type I transmembrane proteins. The N terminus contains an Ig-like V-type domain and a Ser/Thr-rich mucin stalk as a co-inhibitory receptor. The C-terminal tail oriented toward the cytosol predominantly mediates intracellular signaling. Methods: This review discusses the structural features and functions of TIM-3, specifically on its role in mediating immune responses in different cell types, and the rationale for TIM-3-targeted cancer immunotherapy. Results: TIM-3 has gained significant importance to be a potential biomarker in cancer immunotherapy. It has been shown that blockade with checkpoint inhibitors promotes anti-tumor immunity and inhibits tumor growth in several preclinical tumor models. Conclusion: TIM-3 is an immune regulating molecule expressed on several cell types, including IFNγ-producing T-cells, FoxP3+ Treg cells, and innate immune cells. The roles of TIM-3 in immunosuppression support its merit as a target for cancer immunotherapy.

scholarly journals Characterization of Endogenous SERINC5 Protein as Anti-HIV-1 Factor

2019 ◽  
Vol 93 (24) ◽  
Author(s):  
Vânia Passos ◽  
Thomas Zillinger ◽  
Nicoletta Casartelli ◽  
Amelie S. Wachs ◽  
Shuting Xu ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Surface ◽  
Subcellular Localization ◽  
Transmembrane Protein ◽  
Type I ◽  
Accessory Gene ◽  
Protein Levels ◽  
Specificity And Sensitivity ◽  
Hiv 1

ABSTRACT When expressed in virus-producing cells, the cellular multipass transmembrane protein SERINC5 reduces the infectivity of HIV-1 particles and is counteracted by HIV-1 Nef. Due to the unavailability of an antibody of sufficient specificity and sensitivity, investigation of SERINC5 protein expression and subcellular localization has been limited to heterologously expressed SERINC5. We generated, via CRISPR/Cas9-assisted gene editing, Jurkat T-cell clones expressing endogenous SERINC5 bearing an extracellularly exposed hemagglutinin (HA) epitope [Jurkat SERINC5(iHA knock-in) T cells]. This modification enabled quantification of endogenous SERINC5 protein levels and demonstrated a predominant localization in lipid rafts. Interferon alpha (IFN-α) treatment enhanced cell surface levels of SERINC5 in a ruxolitinib-sensitive manner in the absence of modulation of mRNA and protein quantities. Parental and SERINC5(iHA knock-in) T cells shared the ability to produce infectious wild-type HIV-1 but not an HIV-1 Δnef mutant. SERINC5-imposed reduction of infectivity involved a modest reduction of virus fusogenicity. An association of endogenous SERINC5 protein with HIV-1 Δnef virions was consistently detectable as a 35-kDa species, as opposed to heterologous SERINC5, which presented as a 51-kDa species. Nef-mediated functional counteraction did not correlate with virion exclusion of SERINC5, arguing for the existence of additional counteractive mechanisms of Nef that act on virus-associated SERINC5. In HIV-1-infected cells, Nef triggered the internalization of SERINC5 in the absence of detectable changes of steady-state protein levels. These findings establish new properties of endogenous SERINC5 expression and subcellular localization, challenge existing concepts of HIV-1 Nef-mediated antagonism of SERINC5, and uncover an unprecedented role of IFN-α in modulating SERINC5 through accumulation at the cell surface. IMPORTANCE SERINC5 is the long-searched-for antiviral factor that is counteracted by the HIV-1 accessory gene product Nef. Here, we engineered, via CRISPR/Cas9 technology, T-cell lines that express endogenous SERINC5 alleles tagged with a knocked-in HA epitope. This genetic modification enabled us to study basic properties of endogenous SERINC5 and to verify proposed mechanisms of HIV-1 Nef-mediated counteraction of SERINC5. Using this unique resource, we identified the susceptibility of endogenous SERINC5 protein to posttranslational modulation by type I IFNs and suggest uncoupling of Nef-mediated functional antagonism from SERINC5 exclusion from virions.

scholarly journals IMMU-34. ATRX MUTATIONS PREDICT RESPONSE TO INNATE BASED THERAPY IN GLIOMA

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi126-vi126
Author(s):  
Michelle Bowie ◽  
Seethalakshmi Hariharan ◽  
Janell Hostettler ◽  
Kristen Roso ◽  
Yiping He ◽  
...  
Keyword(s):  
Cell Lines ◽  
Glioma Cell ◽  
Innate Immune ◽  
Type I ◽  
Loss Of Function ◽  
Who Grade ◽  
Immune Signaling ◽  
Innate Immune Signaling ◽  
Recurrent Mutations ◽  
Glioma Cell Lines

Abstract BACKGROUND Innate based immunotherapies are becoming increasingly important for treating brain tumor patients. Gliomas carry recurrent mutations in regulatory genes that control innate immune signaling responses. About 71% of adult WHO grade II and III gliomas and 57% of secondary glioblastomas also carry a loss-of-function mutation in the ATRX gene. ATRX is a SWI-SNF chromatin remodeling protein that has major roles in processes such as cell cycle regulation and maintenance of genomic stability. Recent studies have implicated ATRX in dysfunctional innate immune signaling in cancer cells. However, the role of ATRX in mediating innate immune responses has not been investigated in gliomas. METHODS AND RESULTS Human and mouse glioma cell lines from a variety of genetic contexts have been examined including models which carry IDH/ATRX mutations, IDH 1p-/19q- and ATRX -/- status. Additionally, using Crispr-Cas9 technology and cloning cell lines with ATRX deletions, we have derived a series of immune competent and nude mice models. Treating these cell lines with double-stranded RNA based innate stimuli led to an enhanced early induction in phospho-interferon regulatory factor 3 (IRF3) and late induction in phospho-STAT1 in the ATRX knockout (KO) cell lines. A differential increase in interferon-stimulated gene 15 (ISG15) release was also noted in the ATRX KO cell lines, further suggesting that ATRX deletion may enable a potent activation of type I interferon production. A combination of patient-derived glioma cell lines in xenograft models and syngeneic murine glioma models derived from ATRX KO cell lines and controls confirm a survival advantage in both immuno-competent mice and xenografts. Our models are under evaluation with PVSRIPO and other innate based RNA therapies. CONCLUSION Our data suggests that ATRX mutations may confer sensitivity to RNA-based innate immune signaling agonists in gliomas. This potential vulnerability can be targeted in future therapies.

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