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

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.

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Patterns of accumulation of miRNAs encoded by herpes simplex virus during productive infection, latency, and on reactivation

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1422657112 ◽

2014 ◽

Vol 112 (1) ◽

pp. E49-E55 ◽

Cited By ~ 34

Author(s):

Te Du ◽

Zhiyuan Han ◽

Guoying Zhou ◽

Bernard Roizman

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Cultured Cells ◽

Viral Gene Expression ◽

The Body ◽

Productive Infection ◽

Viral Gene ◽

Infected Cells ◽

Simplex Virus ◽

Portal Of Entry

The key events in herpes simplex virus (HSV) infections are (i) replication at a portal of entry into the body modeled by infection of cultured cells; (ii) establishment of a latent state characterized by a sole latency-associated transcript and microRNAs (miRNAs) modeled in murine peripheral ganglia 30 d after inoculation; and (iii) reactivation from the latent state modeled by excision and incubation of ganglia in medium containing anti-NGF antibody for a timespan of a single viral replicative cycle. In this report, we examine the pattern of synthesis and accumulation of 18 HSV-1 miRNAs in the three models. We report the following: (i) H2-3P, H3-3P, H4-3P, H5-3P, H6-3P, and H7-5P accumulated in ganglia harboring latent virus. All but H4-3P were readily detected in productively infected cells, and most likely they originate from three transcriptional units. (ii) H8-5P, H15, H17, H18, H26, and H27 accumulated during reactivation. Of this group, only H26 and H27 could be detected in productively infected cells. (iii) Of the 18 we have examined, only 10 miRNAs were found to accumulate above background levels in productively infected cells. The disparity in the accumulation of miRNAs in cell culture and during reactivation may reflect differences in the patterns of regulation of viral gene expression during productive infection and during reactivation from the latent state.

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Immune Evasion Proteins Enhance Cytomegalovirus Latency in the Lungs

Journal of Virology ◽

10.1128/jvi.01143-09 ◽

2009 ◽

Vol 83 (19) ◽

pp. 10293-10298 ◽

Cited By ~ 15

Author(s):

Verena Böhm ◽

Christof K. Seckert ◽

Christian O. Simon ◽

Doris Thomas ◽

Angélique Renzaho ◽

...

Keyword(s):

T Cells ◽

Cd8 T Cells ◽

Viral Gene Expression ◽

Productive Infection ◽

Effector Memory ◽

Viral Gene ◽

Cmv Infection ◽

Hematopoietic Reconstitution ◽

Latently Infected ◽

Effector Memory Cells

ABSTRACT CD8 T cells control cytomegalovirus (CMV) infection in bone marrow transplantation recipients and persist in latently infected lungs as effector memory cells for continuous sensing of reactivated viral gene expression. Here we have addressed the question of whether viral immunoevasins, glycoproteins that specifically interfere with antigen presentation to CD8 T cells, have an impact on viral latency in the murine model. The data show that deletion of immunoevasin genes in murine CMV accelerates the clearance of productive infection during hematopoietic reconstitution and leads to a reduced latent viral genome load, reduced latency-associated viral transcription, and a lower incidence of recurrence in lung explants.

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Requirement of Multiple cis-Acting Elements in the Human Cytomegalovirus Major Immediate-Early Distal Enhancer for Viral Gene Expression and Replication

Journal of Virology ◽

10.1128/jvi.76.1.313-326.2002 ◽

2002 ◽

Vol 76 (1) ◽

pp. 313-326 ◽

Cited By ~ 49

Author(s):

Jeffery L. Meier ◽

Michael J. Keller ◽

James J. McCoy

Keyword(s):

Gene Expression ◽

Viral Replication ◽

Gene Transcription ◽

Human Cytomegalovirus ◽

Viral Gene Expression ◽

Immediate Early ◽

Viral Gene ◽

Distal Enhancer ◽

Cis Acting ◽

Hcmv Replication

ABSTRACT We have shown previously that the human cytomegalovirus (HCMV) major immediate-early (MIE) distal enhancer is needed for MIE promoter-dependent transcription and viral replication at low multiplicities of infection (MOI). To understand how this region works, we constructed and analyzed a series of HCMVs with various distal enhancer mutations. We show that the distal enhancer is composed of at least two parts that function independently to coordinately activate MIE promoter-dependent transcription and viral replication. One such part is contained in a 47-bp segment that has consensus binding sites for CREB/ATF, SP1, and YY1. At low MOI, these working parts likely function in cis to directly activate MIE gene expression, thus allowing viral replication to ensue. Three findings support the view that these working parts are likely cis-acting elements. (i) Deletion of either part of a bisegmented distal enhancer only slightly alters MIE gene transcription and viral replication. (ii) Reversing the distal enhancer’s orientation largely preserves MIE gene transcription and viral replication. (iii) Placement of stop codons at −300 or −345 in all reading frames does not impair MIE gene transcription and viral replication. Lastly, we show that these working parts are dispensable at high MOI, partly because of compensatory stimulation of MIE promoter activity and viral replication that is induced by a virion-associated component(s) present at a high viral particle/cell ratio. We conclude that the distal enhancer is a complex multicomponent cis-acting region that is required to augment both MIE promoter-dependent transcription and HCMV replication.

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Posttranscriptional Suppression of Interleukin-6 Production by Human Cytomegalovirus

Journal of Virology ◽

10.1128/jvi.79.1.472-485.2005 ◽

2005 ◽

Vol 79 (1) ◽

pp. 472-485 ◽

Cited By ~ 33

Author(s):

Claire Gealy ◽

Marian Denson ◽

Christine Humphreys ◽

Brian McSharry ◽

Gavin Wilkinson ◽

...

Keyword(s):

Gene Expression ◽

Human Cytomegalovirus ◽

Transcriptional Activation ◽

Interleukin 6 ◽

Human Fibroblasts ◽

Intracellular Localization ◽

Viral Gene Expression ◽

Suppressive Effect ◽

Productive Infection ◽

Viral Gene

ABSTRACT Human cytomegalovirus (HCMV) has evolved multiple strategies for suppression of the antiviral response of the infected cell. DNA array technology has revealed that HCMV clearly regulates host gene expression during the course of a productive infection by enhancing, sustaining, or suppressing steady-state levels of cellular transcripts. Interleukin-6 (IL-6) is a pleiotropic cytokine that plays a central role in the immune response to infection. Here we report a detailed study of the effects of HCMV infection on IL-6 expression by human fibroblasts. UV-inactivated virus was found to induce high levels of IL-6 mRNA and protein expression, and IL-6 mRNA remained abundant in cells 16 h after inoculation even though the level of ongoing IL-6 transcription was not significantly enhanced. In lytic HCMV infections, the onset of viral gene expression resulted in two apparently antagonistic effects on IL-6 expression: (i) transcriptional activation, mediated at least in part by the IE2p86 protein, and (ii) posttranscriptional suppression mediated by destabilization of IL-6 mRNA. Transcriptional activation was outweighed by the suppressive effect, such that cells undergoing productive infection produced less IL-6 than cells challenged with inactivated virus. Suppression of IL-6 expression was independent of the viral IL-10 homologue, cmvIL-10. Destabilization of IL-6 mRNA was observed to coincide with the enhanced expression and aberrant intracellular localization of HuR, an mRNA-binding protein known to interact with IL-6 and other mRNAs containing 3′ AU-rich elements. Our data suggest a novel mechanism for gene regulation by HCMV at the posttranscriptional level.

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

10.1101/2020.04.17.046516 ◽

2020 ◽

Cited By ~ 1

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.

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Herpesvirus-mediated stabilization of ICP0 expression neutralizes restriction by TRIM23

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2113060118 ◽

2021 ◽

Vol 118 (51) ◽

pp. e2113060118

Author(s):

Xing Liu ◽

Dhiraj Acharya ◽

Eric Krawczyk ◽

Chase Kangas ◽

Michaela U. Gack ◽

...

Keyword(s):

Viral Replication ◽

Viral Gene Expression ◽

Proteasomal Degradation ◽

Viral Gene ◽

Posttranslational Regulation ◽

Early Proteins ◽

Immediate Early Proteins ◽

Simplex Virus ◽

Functional Analyses ◽

Hsv 1

Herpes simplex virus (HSV) infection relies on immediate early proteins that initiate viral replication. Among them, ICP0 is known, for many years, to facilitate the onset of viral gene expression and reactivation from latency. However, how ICP0 itself is regulated remains elusive. Through genetic analyses, we identify that the viral γ134.5 protein, an HSV virulence factor, interacts with and prevents ICP0 from proteasomal degradation. Furthermore, we show that the host E3 ligase TRIM23, recently shown to restrict the replication of HSV-1 (and certain other viruses) by inducing autophagy, triggers the proteasomal degradation of ICP0 via K11- and K48-linked ubiquitination. Functional analyses reveal that the γ134.5 protein binds to and inactivates TRIM23 through blockade of K27-linked TRIM23 autoubiquitination. Deletion of γ134.5 or ICP0 in a recombinant HSV-1 impairs viral replication, whereas ablation of TRIM23 markedly rescues viral growth. Herein, we show that TRIM23, apart from its role in autophagy-mediated HSV-1 restriction, down-regulates ICP0, whereas viral γ134.5 functions to disable TRIM23. Together, these results demonstrate that posttranslational regulation of ICP0 by virus and host factors determines the outcome of HSV-1 infection.

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Human cytomegalovirus transcriptome activity differs during replication in human fibroblast, epithelial and astrocyte cell lines

Journal of General Virology ◽

10.1099/vir.0.038083-0 ◽

2012 ◽

Vol 93 (5) ◽

pp. 1046-1058 ◽

Cited By ~ 11

Author(s):

James C. Towler ◽

Bahram Ebrahimi ◽

Brian Lane ◽

Andrew J. Davison ◽

Derrick J. Dargan

Keyword(s):

Gene Expression ◽

Human Cytomegalovirus ◽

Growth Kinetics ◽

Viral Gene Expression ◽

Cell Types ◽

Viral Gene ◽

Genome Replication ◽

Cell Type ◽

Low Passage ◽

Temporal Expression Pattern

Broad cell tropism contributes to the pathogenesis of human cytomegalovirus (HCMV), but the extent to which cell type influences HCMV gene expression is unclear. A bespoke HCMV DNA microarray was used to monitor the transcriptome activity of the low passage Merlin strain of HCMV at 12, 24, 48 and 72 h post-infection, during a single round of replication in human fetal foreskin fibroblast cells (HFFF-2s), human retinal pigmented epithelial cells (RPE-1s) and human astrocytoma cells (U373MGs). In order to correlate transcriptome activity with concurrent biological responses, viral cytopathic effect, growth kinetics and genomic loads were examined in the three cell types. The temporal expression pattern of viral genes was broadly similar in HFFF-2s and RPE-1s, but dramatically different in U373MGs. Of the 165 known HCMV protein-coding genes, 41 and 48 were differentially regulated in RPE-1s and U373MGs, respectively, compared with HFFF-2s, and 22 of these were differentially regulated in both RPE-1s and U373MGs. In RPE-1s, all differentially regulated genes were downregulated, but, in U373MGs, some were down- and others upregulated. Differentially regulated genes were identified among the immediate-early, early, early late and true-late viral gene classes. Grouping of downregulated genes according to function at landmark stages of the replication cycle led to the identification of potential bottleneck stages (genome replication, virion assembly, and virion maturation and release) that may account for cell type-dependent viral growth kinetics. The possibility that cell type-specific differences in expressed cellular factors are responsible for modulation of viral gene expression is discussed.

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HCMV exploits STING signaling and counteracts IFN and ISG induction to facilitate dendritic cell infection

10.21203/rs.3.rs-953016/v1 ◽

2022 ◽

Author(s):

Bibiana Costa ◽

Jennifer Becker ◽

Tobias Krammer ◽

Felix Mulenge ◽

Verónica Durán ◽

...

Keyword(s):

Gene Expression ◽

Viral Gene Expression ◽

Productive Infection ◽

Viral Gene ◽

Human Pathogen ◽

Cell Infection ◽

Complex Interactions ◽

Life Threatening ◽

Immunocompromised Hosts

Abstract Human cytomegalovirus (HCMV) is a widespread obligatory human pathogen causing life-threatening disease in immunocompromised hosts. Myeloid cells such as monocyte-derived dendritic cells (moDCs) are targets of HCMV. Here, we performed single-cell RNA sequencing, which revealed infection of most moDCs upon in vitro HCMV exposure, whereas only a fraction of them initiated viral gene expression. We identified three moDC subsets, of which CD1a−/CD86− cells showed the highest susceptibility. Upon HCMV entry, STING activation not only induced IFN-β, but also promoted viral gene expression. Upon progression of infection, IFN-β but not IFN-λ1 expression was inhibited. Similarly, ISG expression was initially induced and then shut off and thus allowed productive infection. Increased viral gene expression was associated with the induction of several pro- (RHOB, HSP1A1, DNAJB1) and anti-viral (RNF213, TNFSF10, IFI16) genes. Thus, moDC permissiveness to HCMV depends on complex interactions between virus sensing, regulation of IFNs/ISGs and viral gene expression.

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Bacteriophage self-counting in the presence of viral replication

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2104163118 ◽

2021 ◽

Vol 118 (51) ◽

pp. e2104163118

Author(s):

Tianyou Yao ◽

Seth Coleman ◽

Thu Vu Phuc Nguyen ◽

Ido Golding ◽

Oleg A. Igoshin

Keyword(s):

Gene Expression ◽

Viral Replication ◽

Viral Gene Expression ◽

Host Cells ◽

Optimal Decision ◽

Viral Gene ◽

Viral Genomes ◽

Viral Copy Number ◽

Viral Copy ◽

Type Phage

When host cells are in low abundance, temperate bacteriophages opt for dormant (lysogenic) infection. Phage lambda implements this strategy by increasing the frequency of lysogeny at higher multiplicity of infection (MOI). However, it remains unclear how the phage reliably counts infecting viral genomes even as their intracellular number increases because of replication. By combining theoretical modeling with single-cell measurements of viral copy number and gene expression, we find that instead of hindering lambda’s decision, replication facilitates it. In a nonreplicating mutant, viral gene expression simply scales with MOI rather than diverging into lytic (virulent) and lysogenic trajectories. A similar pattern is followed during early infection by wild-type phage. However, later in the infection, the modulation of viral replication by the decision genes amplifies the initially modest gene expression differences into divergent trajectories. Replication thus ensures the optimal decision—lysis upon single-phage infection and lysogeny at higher MOI.

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B-Catenin Signaling Regulates the In Vivo Distribution of Hepatitis B Virus Biosynthesis across the Liver Lobule

Journal of Virology ◽

10.1128/jvi.00780-21 ◽

2021 ◽

Author(s):

Grant Tarnow ◽

Alan McLachlan

Keyword(s):

Gene Expression ◽

Transgenic Mice ◽

Viral Replication ◽

Viral Gene Expression ◽

Viral Gene ◽

Central Vein ◽

Liver Lobule ◽

Liver Gene ◽

Mice Liver

β-catenin (Ctnnb1) supports high levels of liver gene expression in hepatocytes in proximity to the central vein functionally defining zone 3 of the liver lobule. This region of the liver lobule supports the highest levels of viral biosynthesis in wildtype HBV transgenic mice. Liver-specific β-catenin-null HBV transgenic mice exhibit a stark loss of high levels of pericentral viral biosynthesis. Additionally, viral replication that does not depend directly on β-catenin activity appears to expand to include hepatocytes of zone 1 of the liver lobule in proximity to the portal vein, a region of the liver that typically lacks significant HBV biosynthesis in wildtype HBV transgenic mice. While the average amount of viral RNA transcripts does not change, viral DNA replication is reduced approximately three-fold. Together, these observations demonstrate that β-catenin signaling represents a major determinant of HBV biosynthesis governing the magnitude and distribution of viral replication across the liver lobule in vivo. Additionally, these findings reveal a novel mechanism for the regulation of HBV biosynthesis that is potentially relevant to the expression of additional liver-specific genes. IMPORTANCE Viral biosynthesis is highest around the central vein in the HBV transgenic mouse model of chronic infection. The associated HBV biosynthetic gradient across the liver lobule is primarily dependent upon β-catenin. In the absence of β-catenin, the gradient of viral gene expression spanning the liver lobule is absent and HBV replication is reduced. Therefore, therapeutically manipulating β-catenin activity in the liver of chronic HBV carriers may reduce circulating infectious virions without greatly modulating viral protein production. Together, these change in viral biosynthesis might limit infection of additional hepatocytes while permitting immunological clearance of previously infected cells, potentially limiting disease persistence.

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