scholarly journals Murine cytomegaloviruses m139 targets DDX3 to curtail interferon production and promote viral replication

2020 ◽  
Author(s):  
Olha Puhach ◽  
Eleonore Ostermann ◽  
Christoph Krisp ◽  
Giada Frascaroli ◽  
Hartmut Schlüter ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Viral Replication ◽  
Human Cytomegalovirus ◽  
Antiviral Treatment ◽  
Cell Types ◽  
The Body ◽  
Productive Infection ◽  
Murine Cytomegalovirus ◽  
Efficient Viral Replication

AbstractCytomegaloviruses (CMV) infect many different cell types and tissues in their respective hosts. Monocytes and macrophages play an important role in CMV dissemination from the site of infection to target organs. Moreover, macrophages are specialized in pathogen sensing and respond to infection by secreting cytokines and interferons. In murine cytomegalovirus (MCMV), a model for human cytomegalovirus, several genes required for efficient replication in macrophages have been identified, but their specific functions remain poorly understood. Here we show that MCMV m139, a gene of the conserved US22 gene family, encodes a protein that interacts with the DEAD box helicase DDX3, a protein involved in pathogen sensing and interferon (IFN) induction, and the E3 ubiquitin ligase UBR5. DDX3 and UBR5 also participate in the transcription, processing, and translation of a subset of cellular mRNAs. We show that m139 inhibits DDX3-mediated IFN-β induction and is necessary for efficient viral replication in bone-marrow derived macrophages. In vivo, m139 is crucial for viral dissemination to local lymph nodes and to the salivary glands. An m139-deficient MCMV also replicated to lower titers in SVEC4-10 endothelial cells. This replication defect was not accompanied by increased IFN-β transcription, but was rescued by knockout of either DDX3 or UBR5. Moreover, m139 co-localized with DDX3 and UBR5 in viral replication compartments in the cell nucleus. These results suggest that m139 inhibits DDX3-mediated IFN-β production in macrophages and antagonizes DDX3 and UBR5-dependent functions related to RNA metabolism in endothelial cells.Author SummaryHuman cytomegalovirus is an opportunistic pathogen that causes severe infections in immunocompromised individuals. The virus infects certain types, such as macrophages and endothelial cells, to ensure its dissemination within the body. Little is known about the viral factors that promote a productive infection of these cell types. The identification of critical viral factors and the molecular pathways they target can lead to the development of novel antiviral treatment strategies. Using the mouse cytomegalovirus as a model, we studied the viral m139 gene, which is important for virus replication in macrophages and endothelial cells and for dissemination in the mouse. This gene encodes a protein that interacts with the host proteins DDX3 and UBR5. Both proteins are involved in gene expression, and the RNA helicase DDX3 also participates in mounting an innate antiviral response. By interacting with DDX3 and UBR5, m139 ensures efficient viral replication in endothelial cells. Importantly, we identify m139 as a new viral DDX3 inhibitor, which curtails the production of interferon in macrophages.

scholarly journals CD147 Promotes Entry of Pentamer-Expressing Human Cytomegalovirus into Epithelial and Endothelial Cells

mBio ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Adam L. Vanarsdall ◽  
Sarah R. Pritchard ◽  
Todd W. Wisner ◽  
Jing Liu ◽  
Ted S. Jardetzky ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Human Cytomegalovirus ◽  
Antiviral Agents ◽  
Growth Factor Receptor ◽  
Surface Protein ◽  
Current Method ◽  
Cell Types ◽  
The Body ◽  
Biologically Relevant

ABSTRACTHuman cytomegalovirus (HCMV) replicates in many diverse cell typesin vivo, and entry into different cells involves distinct entry mechanisms and different envelope glycoproteins. HCMV glycoprotein gB is thought to act as the virus fusogen, apparently after being triggered by different gH/gL proteins that bind distinct cellular receptors or entry mediators. A trimer of gH/gL/gO is required for entry into all cell types, and entry into fibroblasts involves trimer binding to platelet-derived growth factor receptor alpha (PDGFRα). HCMV entry into biologically relevant epithelial and endothelial cells and monocyte-macrophages also requires a pentamer, gH/gL complexed with UL128, UL130, and UL131, and there is evidence that the pentamer binds unidentified receptors. We screened an epithelial cell cDNA library and identified the cell surface protein CD147, which increased entry of pentamer-expressing HCMV into HeLa cells but not entry of HCMV that lacked the pentamer. A panel of CD147-specific monoclonal antibodies inhibited HCMV entry into epithelial and endothelial cells, but not entry into fibroblasts. shRNA silencing of CD147 in endothelial cells inhibited HCMV entry but not entry into fibroblasts. CD147 colocalized with HCMV particles on cell surfaces and in endosomes. CD147 also promoted cell-cell fusion induced by expression of pentamer and gB in epithelial cells. However, soluble CD147 did not block HCMV entry and trimer and pentamer did not bind directly to CD147, supporting the hypothesis that CD147 acts indirectly through other proteins. CD147 represents the first HCMV entry mediator that specifically functions to promote entry of pentamer-expressing HCMV into epithelial and endothelial cells.IMPORTANCEHuman cytomegalovirus infects nearly 80% of the world’s population and causes significant morbidity and mortality. The current method of treatment involves the use of antiviral agents that are prone to resistance and can be highly toxic to patients; currently, there is no vaccine against HCMV available. HCMV infections involve virus dissemination throughout the body, infecting a wide variety of tissues; however, the mechanism of spread is not well understood, particularly with regard to which cellular proteins are utilized by HCMV to establish infection. This report describes the characterization of a newly identified cellular molecule that affects HCMV entry into epithelial and endothelial cells. These results will lead to a better understanding of HCMV pathogenesis and have implications for the development of future therapeutics.

scholarly journals The Endothelin Receptor Antagonist Macitentan Inhibits Human Cytomegalovirus Infection

Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3072
Author(s):  
Natalia Landázuri ◽  
Jennifer Gorwood ◽  
Ylva Terelius ◽  
Fredrik Öberg ◽  
Koon Chu Yaiw ◽  
...  
Keyword(s):  
Human Cytomegalovirus ◽  
Hcmv Infection ◽  
Cell Types ◽  
Productive Infection ◽  
Endothelin Receptor ◽  
Viral Control ◽  
Congenital Birth Defects ◽  
Specific Antagonist ◽  
Human Cytomegalovirus Infection

Human cytomegalovirus (HCMV) infection is an important cause of morbidity and mortality in immunocompromised patients and a major etiological factor for congenital birth defects in newborns. Ganciclovir and its pro-drug valganciclovir are the preferred drugs in use today for prophylaxis and treatment of viremic patients. Due to long treatment times, patients are at risk for developing viral resistance to ganciclovir and to other drugs with a similar mechanism of action. We earlier found that the endothelin receptor B (ETBR) is upregulated during HCMV infection and that it plays an important role in the life cycle of this virus. Here, we tested the hypothesis that ETBR blockade could be used in the treatment of HCMV infection. As HCMV infection is specific to humans, we tested our hypothesis in human cell types that are relevant for HCMV pathogenesis; i.e., endothelial cells, epithelial cells and fibroblasts. We infected these cells with HCMV and treated them with the ETBR specific antagonist BQ788 or ETR antagonists that are approved by the FDA for treatment of pulmonary hypertension; macitentan, its metabolite ACT-132577, bosentan and ambrisentan, and as an anti-viral control, we used ganciclovir or letermovir. At concentrations expected to be relevant in vivo, macitentan, ACT-132577 and BQ788 effectively inhibited productive infection of HCMV. Of importance, macitentan also inhibited productive infection of a ganciclovir-resistant HCMV isolate. Our results suggest that binding or signaling through ETBR is crucial for viral replication, and that selected ETBR blockers inhibit HCMV infection.

Endothelial cells in human cytomegalovirus infection: One host cell out of many or a crucial target for virus spread?

2009 ◽  
Vol 102 (12) ◽  
pp. 1057-1063 ◽  
Author(s):  
Christian Sinzger ◽  
Barbara Adler
Keyword(s):  
Endothelial Cells ◽  
Human Cytomegalovirus ◽  
Cell Types ◽  
The Body ◽  
Cell Type ◽  
Cell Culture Systems ◽  
Human Cytomegalovirus Infection ◽  
Productive Replication

SummaryEndothelial cells (EC) are assumed to play a central role in the spread of human cytomegalovirus (HCMV) throughout the body. Results from in-situ analyses of infected tissues and data from cell culture systems together strongly suggest that vascular EC can support productive replication of HCMV and thus contribute to its haematogeneous dissemination. By inducing an angiogenic response, HCMV may even promote growth of its own habitat. The particular role of EC is further supported by the fact that entry of HCMV into EC is dependent on a complex of the envelope glycoproteins gH and gL with a set of proteins (UL128–131A) which is dispensable for HCMV entry into most other cell types. These molecular requirements may also be reflected by cell type-dependent differences in entry routes, i.e. endocytosis versus fusion at the plasma membrane. An animal model with trackable murine CMV is now available to clarify the pathogenetic role of EC during haematogeneous dissemination of this virus.

scholarly journals Susceptibility of Immature and Mature Langerhans Cell-Type Dendritic Cells to Infection and Immunomodulation by Human Cytomegalovirus

2003 ◽  
Vol 77 (13) ◽  
pp. 7563-7574 ◽  
Author(s):  
Laura Hertel ◽  
Vashti G. Lacaille ◽  
Herbert Strobl ◽  
Elizabeth D. Mellins ◽  
Edward S. Mocarski
Keyword(s):  
Dendritic Cells ◽  
Viral Replication ◽  
Mhc Class Ii ◽  
Human Cytomegalovirus ◽  
Immune Escape ◽  
Viral Gene Expression ◽  
The Body ◽  
Productive Infection ◽  
Viral Gene ◽  
Cmv Infection

ABSTRACT Human cytomegalovirus (CMV) infection initiates in mucosal epithelia and disseminates via leukocytes throughout the body. Langerhans cells (LCs), the immature dendritic cells (DCs) that reside in epithelial tissues, are among the first cells to encounter virus and may play important roles in the immune response, as well as in pathogenesis as hosts for viral replication and as vehicles for dissemination. Here, we demonstrate that CD34+ progenitor cell-derived LC-type DCs exhibit a differentiation state-dependent susceptibility to CMV infection. In contrast to the small percentage (3 to 4%) of the immature LCs that supported infection, a high percentage (48 to 74%) of mature, LC-derived DCs were susceptible to infection with endotheliotropic strains (TB40/E or VHL/E) of CMV. These cells were much less susceptible to viral strains AD169varATCC, TownevarRIT3, and Toledo. When exposed to endotheliotropic strains, viral gene expression (IE1/IE2 and other viral gene products) and viral replication proceeded efficiently in LC-derived mature DCs (mDCs). Productive infection was associated with downmodulation of cell surface CD83, CD1a, CD80, CD86, ICAM-1, major histocompatibility complex (MHC) class I, and MHC class II on these cells. In addition, the T-cell proliferative response to allogeneic LC-derived mDCs was attenuated when CMV-infected cultures were used as stimulators. This investigation revealed important characteristics of the interaction between CMV and the LC lineage of DCs, suggesting that LC-derived mDCs are important to viral pathogenesis and immunity through their increased susceptibility to virus replication and virus-mediated immune escape.

scholarly journals Interactions among Four Proteins Encoded by the Human Cytomegalovirus UL112-113 Region Regulate Their Intranuclear Targeting and the Recruitment of UL44 to Prereplication Foci

2006 ◽  
Vol 80 (6) ◽  
pp. 2718-2727 ◽  
Author(s):  
Mi-Young Park ◽  
Young-Eui Kim ◽  
Myong-Rang Seo ◽  
Jae-Rin Lee ◽  
Chan Hee Lee ◽  
...  
Keyword(s):  
Viral Replication ◽  
Human Cytomegalovirus ◽  
Viral Genome ◽  
Promyelocytic Leukemia ◽  
Mapping Study ◽  
Genetic Studies ◽  
Processivity Factor ◽  
Efficient Viral Replication

ABSTRACT Four phosphoproteins, of 34, 43, 50, and 84 kDa, with common amino termini are synthesized via alternative splicing from the UL112-113 region of the human cytomegalovirus genome. Although genetic studies provided evidence that both the UL112 and UL113 loci in the viral genome are required for efficient viral replication, whether the four proteins play specific roles or cooperate in replication is not understood. Here we present evidence, using in vitro and in vivo coimmunoprecipitation assays, that the four UL112-113 proteins both self-interact and interact with each other. A mapping study of the 84-kDa protein showed that the N-terminal region encompassing amino acids 1 to 125, which is shared in all UL112-113 proteins and highly conserved among betaherpesviruses, is required for both self-interaction and nuclear localization as foci. Further localization studies revealed that, unlike the 43-, 50-, and 84-kDa proteins, which were distributed as nuclear punctate forms, the 34-kDa form was located predominantly in the cytoplasm. However, when all four proteins were coexpressed simultaneously, all of the UL112-113 proteins were efficiently localized to the promyelocytic leukemia oncogenic domains. We also found that the ability of the UL112-113 proteins to relocate UL44 (the viral polymerase processivity factor) to prereplication foci relied on self-interaction and reached maximal levels when the four proteins were coexpressed. Therefore, our data suggest that interactions occurring among UL112-113 proteins via their shared N-terminal regions are important to both their intranuclear targeting and the recruitment of UL44 to subnuclear sites for viral replication.

scholarly journals Prolonged activation of NF-κB by human cytomegalovirus promotes efficient viral replication and late gene expression

Virology ◽  
2006 ◽  
Vol 346 (1) ◽  
pp. 15-31 ◽  
Author(s):  
Ian B. DeMeritt ◽  
Jagat P. Podduturi ◽  
A. Michael Tilley ◽  
Maciej T. Nogalski ◽  
Andrew D. Yurochko
Keyword(s):  
Gene Expression ◽  
Viral Replication ◽  
Human Cytomegalovirus ◽  
Late Gene ◽  
Late Gene Expression ◽  
Efficient Viral Replication

scholarly journals Analyses of the pericyte transcriptome in ischemic skeletal muscles

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yuan-chi Teng ◽  
Alfredo Leonardo Porfírio-Sousa ◽  
Giulia Magri Ribeiro ◽  
Marcela Corso Arend ◽  
Lindolfo da Silva Meirelles ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Vascular Endothelial Cells ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Limb Ischemia ◽  
Inflammatory Cells ◽  
Cell Types ◽  
Arterial Disease ◽  
The Body ◽  
Time Points

Abstract Background Peripheral arterial disease (PAD) affects millions of people and compromises quality of life. Critical limb ischemia (CLI), which is the most advanced stage of PAD, can cause nonhealing ulcers and strong chronic pain, and it shortens the patients’ life expectancy. Cell-based angiogenic therapies are becoming a real therapeutic approach to treat CLI. Pericytes are cells that surround vascular endothelial cells to reinforce vessel integrity and regulate local blood pressure and metabolism. In the past decade, researchers also found that pericytes may function as stem or progenitor cells in the body, showing the potential to differentiate into several cell types. We investigated the gene expression profiles of pericytes during the early stages of limb ischemia, as well as the alterations in pericyte subpopulations to better understand the behavior of pericytes under ischemic conditions. Methods In this study, we used a hindlimb ischemia model to mimic CLI in C57/BL6 mice and explore the role of pericytes in regeneration. To this end, muscle pericytes were isolated at different time points after the induction of ischemia. The phenotypes and transcriptomic profiles of the pericytes isolated at these discrete time points were assessed using flow cytometry and RNA sequencing. Results Ischemia triggered proliferation and migration and upregulated the expression of myogenesis-related transcripts in pericytes. Furthermore, the transcriptomic analysis also revealed that pericytes induce or upregulate the expression of a number of cytokines with effects on endothelial cells, leukocyte chemoattraction, or the activation of inflammatory cells. Conclusions Our findings provide a database that will improve our understanding of skeletal muscle pericyte biology under ischemic conditions, which may be useful for the development of novel pericyte-based cell and gene therapies.

Clock gene-independent daily regulation of haemoglobin oxidation in red blood cells

2021 ◽  
Author(s):  
Andrew D. Beale ◽  
Priya Crosby ◽  
Utham K. Valekunja ◽  
Rachel S. Edgar ◽  
Johanna E. Chesham ◽  
...  
Keyword(s):  
Circadian Rhythms ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Human Subjects ◽  
Developmental Regulation ◽  
Physiological Role ◽  
Cell Types ◽  
The Body

AbstractCellular circadian rhythms confer daily temporal organisation upon behaviour and physiology that is fundamental to human health and disease. Rhythms are present in red blood cells (RBCs), the most abundant cell type in the body. Being naturally anucleate, RBC circadian rhythms share key elements of post-translational, but not transcriptional, regulation with other cell types. The physiological function and developmental regulation of RBC circadian rhythms is poorly understood, however, partly due to the small number of appropriate techniques available. Here, we extend the RBC circadian toolkit with a novel biochemical assay for haemoglobin oxidation status, termed “Bloody Blotting”. Our approach relies on a redox-sensitive covalent haem-haemoglobin linkage that forms during cell lysis. Formation of this linkage exhibits daily rhythms in vitro, which are unaffected by mutations that affect the timing of circadian rhythms in nucleated cells. In vivo, haemoglobin oxidation rhythms demonstrate daily variation in the oxygen-carrying and nitrite reductase capacity of the blood, and are seen in human subjects under controlled laboratory conditions as well as in freely-behaving humans. These results extend our molecular understanding of RBC circadian rhythms and suggest they serve an important physiological role in gas transport.

scholarly journals Human Cytomegalovirus Replication and Infection-Induced Syncytia Formation in Labial, Foreskin, and Fetal Lung Fibroblasts

Viruses ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2355
Author(s):  
Alexis Aguiar ◽  
Melissa Galinato ◽  
Maite’ Bradley Silva ◽  
Bryant Toth ◽  
Michael A. McVoy ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Human Cytomegalovirus ◽  
Fetal Lung ◽  
Lung Fibroblasts ◽  
Anatomical Site ◽  
Cmv Infection ◽  
Viral Spread ◽  
Syncytia Formation

Only a handful of cell types, including fibroblasts, epithelial, and endothelial cells, can support human cytomegalovirus (CMV) replication in vitro, in striking contrast to the situation in vivo. While the susceptibility of epithelial and endothelial cells to CMV infection is strongly modulated by their anatomical site of origin, multiple CMV strains have been successfully isolated and propagated on fibroblasts derived from different organs. As oral mucosal cells are likely involved in CMV acquisition, we sought to evaluate the ability of infant labial fibroblasts to support CMV replication, compared to that of commonly used foreskin and fetal lung fibroblasts. No differences were found in the proportion of cells initiating infection, or in the amounts of viral progeny produced after exposure to the fibroblast-adapted CMV strain AD169 or to the endothelial cell-adapted strain TB40/E. Syncytia formation was, however, significantly enhanced in infected labial and lung fibroblasts compared to foreskin-derived cells, and did not occur after infection with AD169. Together, these data indicate that fibroblast populations derived from different tissues are uniformly permissive to CMV infection but retain phenotypic differences of potential importance for infection-induced cell–cell fusion, and ensuing viral spread and pathogenesis in different organs.

scholarly journals Cell type-specific biogenesis of novel vesicles containing viral products in human cytomegalovirus infection

2020 ◽  
Author(s):  
Samina Momtaz ◽  
Belen Molina ◽  
Luwanika Mlera ◽  
Felicia Goodrum ◽  
Jean M. Wilson
Keyword(s):  
Endothelial Cells ◽  
Human Cytomegalovirus ◽  
Biosynthetic Pathway ◽  
Cell Types ◽  
Endocytic Pathway ◽  
Specific Cell ◽  
Cell Type ◽  
Subcellular Compartment ◽  
Increased Risk ◽  
Cell Type Specific

AbstractHuman cytomegalovirus (HCMV), while highly restricted for the human species, infects an unlimited array of cell types in the host. Patterns of infection are dictated by the cell type infected, but cell type-specific factors and how they impact tropism for specific cell types is poorly understood. Previous studies in primary endothelial cells showed that HCMV infection induces large multivesicular-like bodies that incorporate viral products including dense bodies and virions. Here we define the nature of these large vesicles using a recombinant virus where UL32, encoding the pp150 tegument protein, is fused in frame with green fluorescent protein (GFP, TB40/E-UL32-GFP). Cells were fixed and labeled with antibodies against subcellular compartment markers and imaged using confocal and super-resolution microscopy. In fibroblasts, UL32-GFP-positive vesicles were marked with classical markers of MVBs, including CD63 and lysobisphosphatidic acid (LBPA), both classical MVB markers, as well as the clathrin and LAMP1. Unexpectedly, UL32-GFP-positive vesicles in endothelial cells were not labeled by CD63, and LBPA was completely lost from infected cells. We defined these UL32-positive vesicles in endothelial cells using markers for the cis-Golgi (GM130), lysosome (LAMP1), and autophagy (LC3B). These findings suggest that virus-containing MVBs in fibroblasts are derived from the canonical endocytic pathway and takeover classical exosomal release pathway. Virus containing MVBs in HMVECs are derived from the early biosynthetic pathway and exploit a less characterized early Golgi-LAMP1-associated non-canonical secretory autophagy pathway. These results reveal striking cell-type specific membrane trafficking differences in host pathways that are exploited by HCMV.ImportanceHuman cytomegalovirus (HCMV) is a herpesvirus that, like all herpesvirus, that establishes a life long infection. HCMV remains a significant cause of morbidity and mortality in the immunocompromised and HCMV seropositivity is associated with increased risk vascular disease. HCMV infects many cells in the human and the biology underlying the different patterns of infection in different cell types is poorly understood. Endothelial cells are important target of infection that contribute to hematogenous spread of the virus to tissues. Here we define striking differences in the biogenesis of large vesicles that incorporate virions in fibroblasts and endothelial cells. In fibroblasts, HCMV is incorporated into canonical MVBs derived from an endocytic pathway, whereas HCMV matures through vesicles derived from the biosynthetic pathway in endothelial cells. This work defines basic biological differences between these cell types that may impact the outcome of infection.

Sign in / Sign up

Export Citation Format

Share Document