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 ◽  
...  

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.

2014 ◽  
Vol 211 (9) ◽  
pp. 1467-1475 ◽  
Author(s):  
Avelino Teixeira ◽  
Benjamin Yen ◽  
Gabriele Luca Gusella ◽  
Albert G. Thomas ◽  
Michael P. Mullen ◽  
...  

2015 ◽  
Vol 89 (13) ◽  
pp. 6575-6584 ◽  
Author(s):  
Andrew N. Harman ◽  
Najla Nasr ◽  
Alexandra Feetham ◽  
Ani Galoyan ◽  
Abdullateef A. Alshehri ◽  
...  

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.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Elena N. Judd ◽  
Alison R. Gilchrist ◽  
Nicholas R. Meyerson ◽  
Sara L. Sawyer

Abstract Background The Type I interferon response is an important first-line defense against viruses. In turn, viruses antagonize (i.e., degrade, mis-localize, etc.) many proteins in interferon pathways. Thus, hosts and viruses are locked in an evolutionary arms race for dominance of the Type I interferon pathway. As a result, many genes in interferon pathways have experienced positive natural selection in favor of new allelic forms that can better recognize viruses or escape viral antagonists. Here, we performed a holistic analysis of selective pressures acting on genes in the Type I interferon family. We initially hypothesized that the genes responsible for inducing the production of interferon would be antagonized more heavily by viruses than genes that are turned on as a result of interferon. Our logic was that viruses would have greater effect if they worked upstream of the production of interferon molecules because, once interferon is produced, hundreds of interferon-stimulated proteins would activate and the virus would need to counteract them one-by-one. Results We curated multiple sequence alignments of primate orthologs for 131 genes active in interferon production and signaling (herein, “induction” genes), 100 interferon-stimulated genes, and 100 randomly chosen genes. We analyzed each multiple sequence alignment for the signatures of recurrent positive selection. Counter to our hypothesis, we found the interferon-stimulated genes, and not interferon induction genes, are evolving significantly more rapidly than a random set of genes. Interferon induction genes evolve in a way that is indistinguishable from a matched set of random genes (22% and 18% of genes bear signatures of positive selection, respectively). In contrast, interferon-stimulated genes evolve differently, with 33% of genes evolving under positive selection and containing a significantly higher fraction of codons that have experienced selection for recurrent replacement of the encoded amino acid. Conclusion Viruses may antagonize individual products of the interferon response more often than trying to neutralize the system altogether.


2017 ◽  
Author(s):  
Aurore Bochnakian ◽  
Dimitrios G Zisoulis ◽  
Adam Idica ◽  
Anjie Zhen ◽  
Vineet N KewalRamani ◽  
...  

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.


2021 ◽  
Vol 12 ◽  
Author(s):  
Luis Felipe Olguín-Contreras ◽  
Anna N. Mendler ◽  
Grzegorz Popowicz ◽  
Bin Hu ◽  
Elfriede Noessner

Activation of co-stimulatory pathways in cytotoxic T lymphocytes expressing chimeric antigen receptors (CARs) have proven to boost effector activity, tumor rejection and long-term T cell persistence. When using antigen-specific T cell receptors (TCR) instead of CARs, the lack of co-stimulatory signals hampers robust antitumoral response, hence limiting clinical efficacy. In solid tumors, tumor stroma poses an additional hurdle through hindrance of infiltration and active inhibition. Our project aimed at generating chimeric co-stimulatory switch proteins (CSP) consisting of intracellular co-stimulatory domains (ICD) fused to extracellular protein domains (ECD) for which ligands are expressed in solid tumors. The ECD of CD40L was selected for combination with the ICD from the CD28 protein. With this approach, it was expected to not only provide co-stimulation and strengthen the TCR signaling, but also, through the CD40L ECD, facilitate the activation of tumor-resident antigen-presenting cells (APCs), modulate activation of tumor endothelium and induce TCR-MHC independent apoptotic effect on tumor cells. Since CD28 and CD40L belong to different classes of transmembrane proteins (type I and type II, respectively), creating a chimeric protein presented a structural and functional challenge. We present solutions to this challenge describing different CSP formats that were successfully expressed in human T cells along with an antigen-specific TCR. The level of surface expression of the CSPs depended on their distinct design and the state of T cell activation. In particular, CSPs were upregulated by TCR stimulation and downregulated following interaction with CD40 on target cells. Ligation of the CSP in the context of TCR-stimulation modulated intracellular signaling cascades and led to improved TCR-induced cytokine secretion and cytotoxicity. Moreover, the CD40L ECD exhibited activity as evidenced by effective maturation and activation of B cells and DCs. CD40L:CD28 CSPs are a new type of switch proteins designed to exert dual beneficial antitumor effect by acting directly on the gene-modified T cells and simultaneously on tumor cells and tumor-supporting cells of the TME. The observed effects suggest that they constitute a promising tool to be included in the engineering process of T cells to endow them with complementary features for improved performance in the tumor milieu.


2017 ◽  
Author(s):  
Sean Matthew McCauley ◽  
Kyusik Kim ◽  
Anetta Nowosielska ◽  
Ann Dauphin ◽  
Leonid Yurkovetskiy ◽  
...  

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.


2021 ◽  
Author(s):  
Laurent Hany ◽  
Marc-Olivier Turmel ◽  
Corinne Barat ◽  
Michel Ouellet ◽  
Michel J. Tremblay

While combination antiretroviral therapy maintains undetectable viremia in People Living With HIV (PLWH), a life-long treatment is necessary to prevent viremic rebound after therapy cessation. This rebound seemed mainly caused by long lived HIV-1 latently infected cells reversing to a viral productive status. Reversing latency and elimination of these cells by the so-called shock and kill strategy is one of the main investigated leads to achieve an HIV-1 cure. Small molecules referred as latency reversal agents (LRAs) proved to efficiently reactivate latent CD4 + T cells. However, LRAs impact on de novo infection or HIV-1 production in productively infected macrophages remain elusive. Nontoxic doses of bryostatin-1, JQ1 and romidepsin were investigated in human monocyte-derived macrophages (MDMs). Treatment with bryostatin-1 or romidepsin resulted in a downregulation of CD4 and CCR5 receptors respectively, accompanied by a reduction of R5 tropic virus infection. HIV-1 replication was mainly regulated by receptor modulation for bryostatin-1, while romidepsin effect rely on upregulation of SAMHD1 activity. LRA stimulation of chronically infected cells did not enhance neither HIV-1 production nor gene expression. Surprisingly, bryostatin-1 caused a major decrease in viral production. This effect was not viral strain specific but appears to occur only in myeloid cells. Bryostatin-1 treatment of infected MDMs led to decreased amounts of capsid and matrix mature proteins with little to no modulation of precursors. Our observations revealed that bryostatin-1-treated myeloid and CD4 + T cells are responding differently upon HIV-1 infection. Therefore, additional studies are warranted to more fully assess the efficiency of HIV-1 eradicating strategies. Importance HIV-1 persists in a cellular latent form despite therapy that quickly propagates infection upon treatment interruption. Reversing latency would contribute to eradicate these cells, closing a gap to a cure. Macrophages are an acknowledged HIV-1 reservoir during therapy and are suspected to harbor latency establishment in vivo . Yet, the impact of latency reversal agents (LRAs) on HIV-1 infection and viral production in human macrophages is poorly known but nonetheless crucial to probe the safety of this strategy. In this in vitro study, we discovered encouraging anti-replicative features of distinct LRAs in human macrophages. We also described a new viral production inhibition mechanism by protein kinase C agonists which is specific to myeloid cells. This study provides new insights on HIV-1 propagation restriction potentials by LRAs in human macrophages and underline the importance of assessing latency reversal strategy on all HIV-1 targeted cells.


2019 ◽  
Vol 93 (24) ◽  
Author(s):  
Vânia Passos ◽  
Thomas Zillinger ◽  
Nicoletta Casartelli ◽  
Amelie S. Wachs ◽  
Shuting Xu ◽  
...  

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.


2019 ◽  
Vol 93 (11) ◽  
Author(s):  
Jennifer A. Juno ◽  
Kathleen M. Wragg ◽  
Anne B. Kristensen ◽  
Wen Shi Lee ◽  
Kevin J. Selva ◽  
...  

ABSTRACT Sexual HIV-1 transmission occurs primarily in the presence of semen. Although data from macaque studies suggest that CCR5+ CD4+ T cells are initial targets for HIV-1 infection, the impact of semen on T cell CCR5 expression and ligand production remains inconclusive. To determine if semen modulates the lymphocyte CCR5 receptor/ligand axis, primary human T cell CCR5 expression and natural killer (NK) cell anti-HIV-1 antibody-dependent beta chemokine production was assessed following seminal plasma (SP) exposure. Purified T cells produce sufficient quantities of RANTES to result in a significant decline in CCR5bright T cell frequency following 16 h of SP exposure (P = 0.03). Meanwhile, NK cells retain the capacity to produce limited amounts of MIP-1α/MIP-1β in response to anti-HIV-1 antibody-dependent stimulation (median, 9.5% MIP-1α+ and/or MIP-1β+), despite the immunosuppressive nature of SP. Although these in vitro experiments suggest that SP-induced CCR5 ligand production results in the loss of surface CCR5 expression on CD4+ T cells, the in vivo implications are unclear. We therefore vaginally exposed five pigtail macaques to SP and found that such exposure resulted in an increase in CCR5+ HIV-1 target cells in three of the animals. The in vivo data support a growing body of evidence suggesting that semen exposure recruits target cells to the vagina that are highly susceptible to HIV-1 infection, which has important implications for HIV-1 transmission and vaccine design. IMPORTANCE The majority of HIV-1 vaccine studies do not take into consideration the impact that semen exposure might have on the mucosal immune system. In this study, we demonstrate that seminal plasma (SP) exposure can alter CCR5 expression on T cells. Importantly, in vitro studies of T cells in culture cannot replicate the conditions under which immune cells might be recruited to the genital mucosa in vivo, leading to potentially erroneous conclusions about the impact of semen on mucosal HIV-1 susceptibility.


2014 ◽  
Vol 89 (1) ◽  
pp. 97-109 ◽  
Author(s):  
Shayarana L. Gooneratne ◽  
Jonathan Richard ◽  
Wen Shi Lee ◽  
Andrés Finzi ◽  
Stephen J. Kent ◽  
...  

ABSTRACTMany attempts to design prophylactic human immunodeficiency virus type 1 (HIV-1) vaccines have focused on the induction of neutralizing antibodies (Abs) that block infection by free virions. Despite the focus on viral particles, virus-infected cells, which can be found within mucosal secretions, are more infectious than free virus bothin vitroandin vivo. Furthermore, assessment of human transmission couples suggests infected seminal lymphocytes might be responsible for a proportion of HIV-1 transmissions. Although vaccines that induce neutralizing Abs are sought, only some broadly neutralizing Abs efficiently block cell-to-cell transmission of HIV-1. As HIV-1 vaccines need to elicit immune responses capable of controlling both free and cell-associated virus, we evaluated the potential of natural killer (NK) cells to respond in an Ab-dependent manner to allogeneic T cells bearing HIV-1 antigens. This study presents data measuring Ab-dependent anti-HIV-1 NK cell responses to primary and transformed allogeneic T-cell targets. We found that NK cells are robustly activated in an anti-HIV-1 Ab-dependent manner against allogeneic targets and that tested target cells are subject to Ab-dependent cytolysis. Furthermore, the educated KIR3DL1+NK cell subset from HLA-Bw4+individuals exhibits an activation advantage over the KIR3DL1−subset that contains both NK cells educated through other receptor/ligand combinations and uneducated NK cells. These results are intriguing and important for understanding the regulation of Ab-dependent NK cell responses and are potentially valuable for designing Ab-dependent therapies and/or vaccines.IMPORTANCENK cell-mediated anti-HIV-1 antibody-dependent functions have been associated with protection from infection and disease progression; however, their role in protecting from infection with allogeneic cells infected with HIV-1 is unknown. We found that HIV-1-specific ADCC antibodies bound to allogeneic cells infected with HIV-1 or coated with HIV-1 gp120 were capable of activating NK cells and/or trigging cytolysis of the allogeneic target cells. This suggests ADCC may be able to assist in preventing infection with cell-associated HIV-1. In order to fully utilize NK cell-mediated Ab-dependent effector functions, it might also be important that educated NK cells, which hold the highest activation potential, can become activated against targets bearing HIV-1 antigens and expressing the ligands for self-inhibitory receptors. Here, we show that with Ab-dependent stimulation, NK cells expressing inhibitory receptors can mediate robust activation against targets expressing the ligands for those receptors.


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