Epstein-Barr virus origin of lytic replication mediates association of replicating episomes with promyelocytic leukaemia protein nuclear bodies and replication compartments.

PubMed

Amon, Wolfgang; White, Robert E; Farrell, Paul J

2006-05-01

Epstein-Barr virus (EBV) establishes a latent persistence from which it can be reactivated to undergo lytic replication. Late lytic-cycle gene expression is linked to lytic DNA replication, as it is sensitive to the same inhibitors that block lytic replication, and it has recently been shown that the viral origin of lytic replication (ori lyt) is required in cis for late-gene expression. During the lytic cycle, the viral genome forms replication compartments, which are usually adjacent to promyelocytic leukaemia protein (PML) nuclear bodies. A tetracycline repressor DNA-binding domain-enhanced green fluorescent protein fusion was used to visualize replicating plasmids carrying a tetracycline operator sequence array. ori lyt mediated the production of plasmid replication compartments that were associated with PML nuclear bodies. Plasmids carrying ori lyt and EBV itself were visualized in the same cells and replicated in similar regions of the nucleus, further supporting the validity of the plasmids for studying late-gene regulation.

Association of GATA2 Deficiency With Severe Primary Epstein-Barr Virus (EBV) Infection and EBV-associated Cancers

PubMed Central

Cohen, Jeffrey I.; Dropulic, Lesia; Hsu, Amy P.; Zerbe, Christa S.; Krogmann, Tammy; Dowdell, Kennichi; Hornung, Ronald L.; Lovell, Jana; Hardy, Nancy; Hickstein, Dennis; Cowen, Edward W.; Calvo, Katherine R.; Pittaluga, Stefania; Holland, Steven M.

2016-01-01

Background. Most patients infected with Epstein-Barr virus (EBV) are asymptomatic, have nonspecific symptoms, or have self-limiting infectious mononucleosis. EBV, however, may result in severe primary disease or cancer. Methods. We report EBV diseases associated with GATA2 deficiency at one institution and describe the hematology, virology, and cytokine findings. Results. Seven patients with GATA2 deficiency developed severe EBV disease. Three presented with EBV infectious mononucleosis requiring hospitalization, 1 had chronic active EBV disease (B-cell type), 1 had EBV-associated hydroa vacciniforme–like lymphoma with hemophagocytic lymphohistiocytosis, and 2 had EBV-positive smooth muscle tumors. Four of the 7 patients had severe warts and 3 had disseminated nontuberculous mycobacterial infections. All of the patients had low numbers of monocytes, B cells, CD4 T cells, and natural killer cells. All had elevated levels of EBV in the blood; 2 of 3 patients tested had expression of the EBV major immediate-early gene in the blood indicative of active EBV lytic infection. Mean plasma levels of tumor necrosis factor α, interferon γ, and interferon gamma-induced protein 10 were higher in patients with GATA2 deficiency than in controls. Conclusions. GATA2 is the first gene associated with EBV hydroa vacciniforme–like lymphoma. GATA2 deficiency should be considered in patients with severe primary EBV infection or EBV-associated cancer, especially in those with disseminated nontuberculous mycobacterial disease and warts. PMID:27169477

CUX1/Wnt signaling regulates Epithelial Mesenchymal Transition in EBV infected epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malizia, Andrea P.; Lacey, Noreen; Walls, Dermot

Idiopathic pulmonary fibrosis (IPF) is a refractory and lethal interstitial lung disease characterized by alveolar epithelial cells apoptosis, fibroblast proliferation and extra-cellular matrix protein deposition. EBV, localised to alveolar epithelial cells of pulmonary fibrosis patients is associated with a poor prognosis. A strategy based on microarray-differential gene expression analysis to identify molecular drivers of EBV-associated lung fibrosis was utilized. Alveolar epithelial cells were infected with EBV to identify genes whose expression was altered following TGF{beta}1-mediated lytic phase. EBV lytic reactivation by TGF{beta}1 drives a selective alteration in CUX1 variant (a) (NCBI accession number NM{sub 1}81552) expression, inducing activation of non-canonicalmore » Wnt pathway mediators, implicating it in Epithelial Mesenchymal Transition (EMT), the molecular event underpinning scar production in tissue fibrosis. The role of EBV in EMT can be attenuated by antiviral strategies and inhibition of Wnt signaling by using All-Trans Retinoic Acids (ATRA). Activation of non-canonical Wnt signaling pathway by EBV in epithelial cells suggests a novel mechanism of EMT via CUX1 signaling. These data present a framework for further description of the link between infectious agents and fibrosis, a significant disease burden.« less

Association of GATA2 Deficiency With Severe Primary Epstein-Barr Virus (EBV) Infection and EBV-associated Cancers.

PubMed

Cohen, Jeffrey I; Dropulic, Lesia; Hsu, Amy P; Zerbe, Christa S; Krogmann, Tammy; Dowdell, Kennichi; Hornung, Ronald L; Lovell, Jana; Hardy, Nancy; Hickstein, Dennis; Cowen, Edward W; Calvo, Katherine R; Pittaluga, Stefania; Holland, Steven M

2016-07-01

Most patients infected with Epstein-Barr virus (EBV) are asymptomatic, have nonspecific symptoms, or have self-limiting infectious mononucleosis. EBV, however, may result in severe primary disease or cancer. We report EBV diseases associated with GATA2 deficiency at one institution and describe the hematology, virology, and cytokine findings. Seven patients with GATA2 deficiency developed severe EBV disease. Three presented with EBV infectious mononucleosis requiring hospitalization, 1 had chronic active EBV disease (B-cell type), 1 had EBV-associated hydroa vacciniforme-like lymphoma with hemophagocytic lymphohistiocytosis, and 2 had EBV-positive smooth muscle tumors. Four of the 7 patients had severe warts and 3 had disseminated nontuberculous mycobacterial infections. All of the patients had low numbers of monocytes, B cells, CD4 T cells, and natural killer cells. All had elevated levels of EBV in the blood; 2 of 3 patients tested had expression of the EBV major immediate-early gene in the blood indicative of active EBV lytic infection. Mean plasma levels of tumor necrosis factor α, interferon γ, and interferon gamma-induced protein 10 were higher in patients with GATA2 deficiency than in controls. GATA2 is the first gene associated with EBV hydroa vacciniforme-like lymphoma. GATA2 deficiency should be considered in patients with severe primary EBV infection or EBV-associated cancer, especially in those with disseminated nontuberculous mycobacterial disease and warts. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Bromodomain and extraterminal inhibitors block the Epstein-Barr virus lytic cycle at two distinct steps.

PubMed

Keck, Kristin M; Moquin, Stephanie A; He, Amanda; Fernandez, Samantha G; Somberg, Jessica J; Liu, Stephanie M; Martinez, Delsy M; Miranda, Jj L

2017-08-11

Lytic infection by the Epstein-Barr virus (EBV) poses numerous health risks, such as infectious mononucleosis and lymphoproliferative disorder. Proteins in the bromodomain and extraterminal (BET) family regulate multiple stages of viral life cycles and provide promising intervention targets. Synthetic small molecules can bind to the bromodomains and disrupt function by preventing recognition of acetylated lysine substrates. We demonstrate that JQ1 and other BET inhibitors block two different steps in the sequential cascade of the EBV lytic cycle. BET inhibitors prevent expression of the viral immediate-early protein BZLF1. JQ1 alters transcription of genes controlled by the host protein BACH1, and BACH1 knockdown reduces BZLF1 expression. BET proteins also localize to the lytic origin of replication (OriLyt) genetic elements, and BET inhibitors prevent viral late gene expression. There JQ1 reduces BRD4 recruitment during reactivation to preclude replication initiation. This represents a rarely observed dual mode of action for drugs.

Epstein-Barr virus (EBV) recombinants: use of positive selection markers to rescue mutants in EBV-negative B-lymphoma cells.

PubMed

Wang, F; Marchini, A; Kieff, E

1991-04-01

The objective of these experiments was to develop strategies for creation and identification of recombinant mutant Epstein-Barr viruses (EBV). EBV recombinant molecular genetics has been limited to mutations within a short DNA segment deleted from a nontransforming EBV and an underlying strategy which relies on growth transformation of primary B lymphocytes for identification of recombinants. Thus, mutations outside the deletion or mutations which affect transformation cannot be easily recovered. In these experiments we investigated whether a toxic drug resistance gene, guanine phosphoribosyltransferase or hygromycin phosphotransferase, driven by the simian virus 40 promoter can be recombined into the EBV genome and can function to identify B-lymphoma cells infected with recombinant virus. Two different strategies were used to recombine the drug resistance marker into the EBV genome. Both utilized transfection of partially permissive, EBV-infected B95-8 cells and positive selection for cells which had incorporated a functional drug resistance gene. In the first series of experiments, B95-8 clones were screened for transfected DNA that had recombined into the EBV genome. In the second series of experiments, the transfected drug resistance marker was linked to the plasmid and lytic EBV origins so that it was maintained as an episome and could recombine with the B95-8 EBV genome during virus replication. The recombinant EBV from either experiment could be recovered by infection and toxic drug selection of EBV-negative B-lymphoma cells. The EBV genome in these B-lymphoma cells is frequently an episome. Virus genes associated with latent infection of primary B lymphocytes are expressed. Expression of Epstein-Barr virus nuclear antigen 2 (EBNA-2) and the EBNA-3 genes is variable relative to that of EBNA-1, as is characteristic of some naturally infected Burkitt tumor cells. Moreover, the EBV-infected B-lymphoma cells are often partially permissive for early replicative

Epstein-Barr virus (EBV) recombinants: use of positive selection markers to rescue mutants in EBV-negative B-lymphoma cells.

PubMed Central

Wang, F; Marchini, A; Kieff, E

1991-01-01

The objective of these experiments was to develop strategies for creation and identification of recombinant mutant Epstein-Barr viruses (EBV). EBV recombinant molecular genetics has been limited to mutations within a short DNA segment deleted from a nontransforming EBV and an underlying strategy which relies on growth transformation of primary B lymphocytes for identification of recombinants. Thus, mutations outside the deletion or mutations which affect transformation cannot be easily recovered. In these experiments we investigated whether a toxic drug resistance gene, guanine phosphoribosyltransferase or hygromycin phosphotransferase, driven by the simian virus 40 promoter can be recombined into the EBV genome and can function to identify B-lymphoma cells infected with recombinant virus. Two different strategies were used to recombine the drug resistance marker into the EBV genome. Both utilized transfection of partially permissive, EBV-infected B95-8 cells and positive selection for cells which had incorporated a functional drug resistance gene. In the first series of experiments, B95-8 clones were screened for transfected DNA that had recombined into the EBV genome. In the second series of experiments, the transfected drug resistance marker was linked to the plasmid and lytic EBV origins so that it was maintained as an episome and could recombine with the B95-8 EBV genome during virus replication. The recombinant EBV from either experiment could be recovered by infection and toxic drug selection of EBV-negative B-lymphoma cells. The EBV genome in these B-lymphoma cells is frequently an episome. Virus genes associated with latent infection of primary B lymphocytes are expressed. Expression of Epstein-Barr virus nuclear antigen 2 (EBNA-2) and the EBNA-3 genes is variable relative to that of EBNA-1, as is characteristic of some naturally infected Burkitt tumor cells. Moreover, the EBV-infected B-lymphoma cells are often partially permissive for early replicative

Epstein-Barr Virus BKRF4 Gene Product Is Required for Efficient Progeny Production.

PubMed

Masud, H M Abdullah Al; Watanabe, Takahiro; Yoshida, Masahiro; Sato, Yoshitaka; Goshima, Fumi; Kimura, Hiroshi; Murata, Takayuki

2017-12-01

Epstein-Barr virus (EBV), a member of human gammaherpesvirus, infects mainly B cells. EBV has two alternative life cycles, latent and lytic, and is reactivated occasionally from the latent stage to the lytic cycle. To combat EBV-associated disorders, understanding the molecular mechanisms of the EBV lytic replication cycle is also important. Here, we focused on an EBV lytic gene, BKRF4. Using our anti-BKRF4 antibody, we revealed that the BKRF4 gene product is expressed during the lytic cycle with late kinetics. To characterize the role of BKRF4, we constructed BKRF4-knockout mutants using the bacterial artificial chromosome (BAC) and CRISPR/Cas9 systems. Although disruption of the BKRF4 gene had almost no effect on viral protein expression and DNA synthesis, it significantly decreased progeny virion levels in HEK293 and Akata cells. Furthermore, we show that BKRF4 is involved not only in production of progeny virions but also in increasing the infectivity of the virus particles. Immunoprecipitation assays revealed that BKRF4 interacted with a virion protein, BGLF2. We showed that the C-terminal region of BKRF4 was critical for this interaction and for efficient progeny production. Immunofluorescence analysis revealed that BKRF4 partially colocalized with BGLF2 in the nucleus and perinuclear region. Finally, we showed that BKRF4 is a phosphorylated, possible tegument protein and that the EBV protein kinase BGLF4 may be important for this phosphorylation. Taken together, our data suggest that BKRF4 is involved in the production of infectious virions. IMPORTANCE Although the latent genes of EBV have been studied extensively, the lytic genes are less well characterized. This study focused on one such lytic gene, BKRF4, which is conserved only among gammaherpesviruses (ORF45 of Kaposi's sarcoma-associated herpesvirus or murine herpesvirus 68). After preparing the BKRF4 knockout virus using B95-8 EBV-BAC, we demonstrated that the BKRF4 gene was involved in infectious

EBV and systemic lupus erythematosus: a new perspective.

PubMed

Gross, Andrew J; Hochberg, Donna; Rand, William M; Thorley-Lawson, David A

2005-06-01

We have proposed that EBV uses mature B cell biology to access memory B cells as a site of persistent infection. A central feature of this model is that EBV adapts its gene expression profile to the state of the B cell it resides in and that the level of infection is stable over time. This led us to question whether changes in the behavior or regulation of mature B cells would alter the state of EBV persistence. To investigate this, we studied the impact of systemic lupus erythematosus (SLE), a disease characterized by immune dysfunction, on EBV infection. We show that patients with SLE have abnormally high frequencies of EBV-infected cells in their blood, and this is associated with the occurrence of SLE disease flares. Although patients with SLE have frequencies of infected cells comparable to those seen in immunosuppressed patients, in SLE the effect was independent of immunosuppressive therapy. Aberrant expression of viral lytic (BZLF1) and latency (latency membrane proteins 1 and 2a) genes was also detected in the blood of SLE patients. We conclude that the abnormal regulation of EBV infection in SLE patients reflects the sensitivity of the virus to perturbation of the immune system.

Transcriptional profiling of Epstein–Barr virus (EBV) genes and host cellular genes in nasal NK/T-cell lymphoma and chronic active EBV infection

PubMed Central

Zhang, Y; Ohyashiki, J H; Takaku, T; Shimizu, N; Ohyashiki, K

2006-01-01

Nasal NK/T-cell lymphoma is an aggressive subtype of non-Hodgkin lymphoma (NHL) that is closely associated with Epstein–Barr virus (EBV). The clonal expansion of EBV-infected NK or T cells is also seen in patients with chronic active EBV (CAEBV) infection, suggesting that two diseases might share a partially similar mechanism by which EBV affects host cellular gene expression. To understand the pathogenesis of EBV-associated NK/T-cell lymphoproliferative disorders (LPD) and design new therapies, we employed a novel EBV DNA microarray to compare patterns of EBV expression in six cell lines established from EBV-associated NK/T-cell LPD. We found that expression of BZLF1, which encodes the immediate-early gene product Zta, was expressed in SNK/T cells and the expression levels were preferentially high in cell lines from CAEBV infection. We also analyzsd the gene expression patterns of host cellular genes using a human oligonucleotide DNA microarray. We identified a subset of pathogenically and clinically relevant host cellular genes, including TNFRSF10D, CDK2, HSPCA, IL12A as a common molecular biological properties of EBV-associated NK/T-cell LPD and a subset of genes, such as PDCD4 as a putative contributor for disease progression. This study describes a novel approach from the aspects of viral and host gene expression, which could identify novel therapeutic targets in EBV-associated NK/T-cell LPD. PMID:16449999

PARP1 restricts Epstein Barr Virus lytic reactivation by binding the BZLF1 promoter.

PubMed

Lupey-Green, Lena N; Moquin, Stephanie A; Martin, Kayla A; McDevitt, Shane M; Hulse, Michael; Caruso, Lisa B; Pomerantz, Richard T; Miranda, Jj L; Tempera, Italo

2017-07-01

The Epstein Barr virus (EBV) genome persists in infected host cells as a chromatinized episome and is subject to chromatin-mediated regulation. Binding of the host insulator protein CTCF to the EBV genome has an established role in maintaining viral latency type, and in other herpesviruses, loss of CTCF binding at specific regions correlates with viral reactivation. Here, we demonstrate that binding of PARP1, an important cofactor of CTCF, at the BZLF1 lytic switch promoter restricts EBV reactivation. Knockdown of PARP1 in the Akata-EBV cell line significantly increases viral copy number and lytic protein expression. Interestingly, CTCF knockdown has no effect on viral reactivation, and CTCF binding across the EBV genome is largely unchanged following reactivation. Moreover, EBV reactivation attenuates PARP activity, and Zta expression alone is sufficient to decrease PARP activity. Here we demonstrate a restrictive function of PARP1 in EBV lytic reactivation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Drug Modulators of B Cell Signaling Pathways and Epstein-Barr Virus Lytic Activation.

PubMed

Kosowicz, John G; Lee, Jaeyeun; Peiffer, Brandon; Guo, Zufeng; Chen, Jianmeng; Liao, Gangling; Hayward, S Diane; Liu, Jun O; Ambinder, Richard F

2017-08-15

Epstein-Barr virus (EBV) is a ubiquitous human gammaherpesvirus that establishes a latency reservoir in B cells. In this work, we show that ibrutinib, idelalisib, and dasatinib, drugs that block B cell receptor (BCR) signaling and are used in the treatment of hematologic malignancies, block BCR-mediated lytic induction at clinically relevant doses. We confirm that the immunosuppressive drugs cyclosporine and tacrolimus also inhibit BCR-mediated lytic induction but find that rapamycin does not inhibit BCR-mediated lytic induction. Further investigation shows that mammalian target of rapamycin complex 2 (mTORC2) contributes to BCR-mediated lytic induction and that FK506-binding protein 12 (FKBP12) binding alone is not adequate to block activation. Finally, we show that BCR signaling can activate EBV lytic induction in freshly isolated B cells from peripheral blood mononuclear cells (PBMCs) and that activation can be inhibited by ibrutinib or idelalisib. IMPORTANCE EBV establishes viral latency in B cells. Activation of the B cell receptor pathway activates lytic viral expression in cell lines. Here we show that drugs that inhibit important kinases in the BCR signaling pathway inhibit activation of lytic viral expression but do not inhibit several other lytic activation pathways. Immunosuppressant drugs such as cyclosporine and tacrolimus but not rapamycin also inhibit BCR-mediated EBV activation. Finally, we show that BCR activation of lytic infection occurs not only in tumor cell lines but also in freshly isolated B cells from patients and that this activation can be blocked by BCR inhibitors. Copyright © 2017 American Society for Microbiology.

Activation and Repression of Epstein-Barr Virus and Kaposi's Sarcoma-Associated Herpesvirus Lytic Cycles by Short- and Medium-Chain Fatty Acids

PubMed Central

Gorres, Kelly L.; Daigle, Derek; Mohanram, Sudharshan

2014-01-01

ABSTRACT The lytic cycles of Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) are induced in cell culture by sodium butyrate (NaB), a short-chain fatty acid (SCFA) histone deacetylase (HDAC) inhibitor. Valproic acid (VPA), another SCFA and an HDAC inhibitor, induces the lytic cycle of KSHV but blocks EBV lytic reactivation. To explore the hypothesis that structural differences between NaB and VPA account for their functional effects on the two related viruses, we investigated the capacity of 16 structurally related short- and medium-chain fatty acids to promote or prevent lytic cycle reactivation. SCFAs differentially affected EBV and KSHV reactivation. KSHV was reactivated by all SCFAs that are HDAC inhibitors, including phenylbutyrate. However, several fatty acid HDAC inhibitors, such as isobutyrate and phenylbutyrate, did not reactivate EBV. Reactivation of KSHV lytic transcripts could not be blocked completely by any fatty acid tested. In contrast, several medium-chain fatty acids inhibited lytic activation of EBV. Fatty acids that blocked EBV reactivation were more lipophilic than those that activated EBV. VPA blocked activation of the BZLF1 promoter by NaB but did not block the transcriptional function of ZEBRA. VPA also blocked activation of the DNA damage response that accompanies EBV lytic cycle activation. Properties of SCFAs in addition to their effects on chromatin are likely to explain activation or repression of EBV. We concluded that fatty acids stimulate the two related human gammaherpesviruses to enter the lytic cycle through different pathways. IMPORTANCE Lytic reactivation of EBV and KSHV is needed for persistence of these viruses and plays a role in carcinogenesis. Our direct comparison highlights the mechanistic differences in lytic reactivation between related human oncogenic gammaherpesviruses. Our findings have therapeutic implications, as fatty acids are found in the diet and produced by the human microbiota

The Epstein-Barr Virus (EBV) in T Cell and NK Cell Lymphomas: Time for a Reassessment

PubMed Central

Gru, A. A.; Haverkos, B. H.; Freud, A. G.; Hastings, J.; Nowacki, N. B.; Barrionuevo, C.; Vigil, C. E.; Rochford, R.; Natkunam, Y.; Baiocchi, R. A.

2015-01-01

While Epstein-Barr virus (EBV) was initially discovered and characterized as an oncogenic virus in B cell neoplasms, it also plays a complex and multifaceted role in T/NK cell lymphomas. In B cell lymphomas, EBV-encoded proteins have been shown to directly promote immortalization and proliferation through stimulation of the NF-κB pathway and increased expression of anti-apoptotic genes. In the context of mature T/NK lymphomas (MTNKL), with the possible exception on extranodal NK/T cell lymphoma (ENKTL), the virus likely plays a more diverse and nuanced role. EBV has been shown to shape the tumor microenvironment by promoting Th2-skewed T cell responses and by increasing the expression of the immune checkpoint ligand PD-L1. The type of cell infected, the amount of plasma EBV DNA, and the degree of viral lytic replication have all been proposed to have prognostic value in T/NK cell lymphomas. Latency patterns of EBV infection have been defined using EBV-infected B cell models and have not been definitively established in T/NK cell lymphomas. Identifying the expression profile of EBV lytic proteins could allow for individualized therapy with the use of antiviral medications. More work needs to be done to determine whether EBV-associated MTNKL have distinct biological and clinical features, which can be leveraged for risk stratification, disease monitoring, and therapeutic purposes. PMID:26449716

Characterization of Epstein-Barr virus (EBV) BZLF1 gene promoter variants and comparison of cellular gene expression profiles in Japanese patients with infectious mononucleosis, chronic active EBV infection, and EBV-associated hemophagocytic lymphohistiocytosis.

PubMed

Imajoh, Masayuki; Hashida, Yumiko; Murakami, Masanao; Maeda, Akihiko; Sato, Tetsuya; Fujieda, Mikiya; Wakiguchi, Hiroshi; Daibata, Masanori

2012-06-01

Epstein-Barr virus (EBV) genotypes can be distinguished based on gene sequence differences in EBV nuclear antigens 2, 3A, 3B, and 3C, and the BZLF1 promoter zone (Zp). EBV subtypes and BZLF1 Zp variants were examined in Japanese patients with infectious mononucleosis, chronic active EBV infection, and EBV-associated hemophagocytic lymphohistiocytosis. The results of EBV typing showed that samples of infectious mononucleosis, chronic active EBV infection, and EBV-associated hemophagocytic lymphohistiocytosis all belonged to EBV type 1. However, sequencing analysis of BZLF1 Zp found three polymorphic Zp variants in the same samples. The Zp-P prototype and the Zp-V3 variant were both detected in infectious mononucleosis and chronic active EBV infection. Furthermore, a novel variant previously identified in Chinese children with infectious mononucleosis, Zp-V1, was also found in 3 of 18 samples of infectious mononucleosis, where it coexisted with the Zp-P prototype. This is the first evidence that the EBV variant distribution in Japanese patients resembles that found in other Asian patients. The expression levels of 29 chronic active EBV infection-associated cellular genes were also compared in the three EBV-related disorders, using quantitative real-time reverse transcription polymerase chain reaction analysis. Two upregulated genes, RIPK2 and CDH9, were identified as common specific markers for chronic active EBV infection in both in vitro and in vivo studies. RIPK2 activates apoptosis and autophagy, and could be responsible for the pathogenesis of chronic active EBV infection. Copyright © 2012 Wiley Periodicals, Inc.

Partial Least Squares Based Gene Expression Analysis in EBV- Positive and EBV-Negative Posttransplant Lymphoproliferative Disorders.

PubMed

Wu, Sa; Zhang, Xin; Li, Zhi-Ming; Shi, Yan-Xia; Huang, Jia-Jia; Xia, Yi; Yang, Hang; Jiang, Wen-Qi

2013-01-01

Post-transplant lymphoproliferative disorder (PTLD) is a common complication of therapeutic immunosuppression after organ transplantation. Gene expression profile facilitates the identification of biological difference between Epstein-Barr virus (EBV) positive and negative PTLDs. Previous studies mainly implemented variance/regression analysis without considering unaccounted array specific factors. The aim of this study is to investigate the gene expression difference between EBV positive and negative PTLDs through partial least squares (PLS) based analysis. With a microarray data set from the Gene Expression Omnibus database, we performed PLS based analysis. We acquired 1188 differentially expressed genes. Pathway and Gene Ontology enrichment analysis identified significantly over-representation of dysregulated genes in immune response and cancer related biological processes. Network analysis identified three hub genes with degrees higher than 15, including CREBBP, ATXN1, and PML. Proteins encoded by CREBBP and PML have been reported to be interact with EBV before. Our findings shed light on expression distinction of EBV positive and negative PTLDs with the hope to offer theoretical support for future therapeutic study.

Human natural killer cells prevent infectious mononucleosis features by targeting lytic Epstein-Barr virus infection

PubMed Central

Chijioke, Obinna; Müller, Anne; Feederle, Regina; Barros, Mario Henrique M.; Krieg, Carsten; Emmel, Vanessa; Marcenaro, Emanuela; Leung, Carol S.; Antsiferova, Olga; Landtwing, Vanessa; Bossart, Walter; Moretta, Alessandro; Hassan, Rocio; Boyman, Onur; Niedobitek, Gerald; Delecluse, Henri-Jacques; Capaul, Riccarda; Münz, Christian

2014-01-01

SUMMARY Primary infection with the human oncogenic Epstein Barr virus (EBV) can result in infectious mononucleosis (IM), a self-limiting disease caused by massive lymphocyte expansion, which predisposes for the development of distinct EBV-associated lymphomas. It remains unclear why some individuals experience this symptomatic primary EBV infection, while the majority acquires the virus asymptomatically. Using a mouse model with reconstituted human immune system components, we show here that depletion of human natural killer (NK) cells enhances IM symptoms and promotes EBV-associated tumorigenesis, mainly due to loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies. PMID:24360958

Increased CD8+ T Cell Response to Epstein-Barr Virus Lytic Antigens in the Active Phase of Multiple Sclerosis

PubMed Central

Angelini, Daniela F.; Serafini, Barbara; Piras, Eleonora; Severa, Martina; Coccia, Eliana M.; Rosicarelli, Barbara; Ruggieri, Serena; Gasperini, Claudio; Buttari, Fabio; Centonze, Diego; Mechelli, Rosella; Salvetti, Marco; Borsellino, Giovanna; Aloisi, Francesca; Battistini, Luca

2013-01-01

It has long been known that multiple sclerosis (MS) is associated with an increased Epstein-Barr virus (EBV) seroprevalence and high immune reactivity to EBV and that infectious mononucleosis increases MS risk. This evidence led to postulate that EBV infection plays a role in MS etiopathogenesis, although the mechanisms are debated. This study was designed to assess the prevalence and magnitude of CD8+ T-cell responses to EBV latent (EBNA-3A, LMP-2A) and lytic (BZLF-1, BMLF-1) antigens in relapsing-remitting MS patients (n = 113) and healthy donors (HD) (n = 43) and to investigate whether the EBV-specific CD8+ T cell response correlates with disease activity, as defined by clinical evaluation and gadolinium-enhanced magnetic resonance imaging. Using HLA class I pentamers, lytic antigen-specific CD8+ T cell responses were detected in fewer untreated inactive MS patients than in active MS patients and HD while the frequency of CD8+ T cells specific for EBV lytic and latent antigens was higher in active and inactive MS patients, respectively. In contrast, the CD8+ T cell response to cytomegalovirus did not differ between HD and MS patients, irrespective of the disease phase. Marked differences in the prevalence of EBV-specific CD8+ T cell responses were observed in patients treated with interferon-β and natalizumab, two licensed drugs for relapsing-remitting MS. Longitudinal studies revealed expansion of CD8+ T cells specific for EBV lytic antigens during active disease in untreated MS patients but not in relapse-free, natalizumab-treated patients. Analysis of post-mortem MS brain samples showed expression of the EBV lytic protein BZLF-1 and interactions between cytotoxic CD8+ T cells and EBV lytically infected plasma cells in inflammatory white matter lesions and meninges. We therefore propose that inability to control EBV infection during inactive MS could set the stage for intracerebral viral reactivation and disease relapse. PMID:23592979

Human natural killer cells prevent infectious mononucleosis features by targeting lytic Epstein-Barr virus infection.

PubMed

Chijioke, Obinna; Müller, Anne; Feederle, Regina; Barros, Mario Henrique M; Krieg, Carsten; Emmel, Vanessa; Marcenaro, Emanuela; Leung, Carol S; Antsiferova, Olga; Landtwing, Vanessa; Bossart, Walter; Moretta, Alessandro; Hassan, Rocio; Boyman, Onur; Niedobitek, Gerald; Delecluse, Henri-Jacques; Capaul, Riccarda; Münz, Christian

2013-12-26

Primary infection with the human oncogenic Epstein-Barr virus (EBV) can result in infectious mononucleosis (IM), a self-limiting disease caused by massive lymphocyte expansion that predisposes for the development of distinct EBV-associated lymphomas. Why some individuals experience this symptomatic primary EBV infection, whereas the majority acquires the virus asymptomatically, remains unclear. Using a mouse model with reconstituted human immune system components, we show that depletion of human natural killer (NK) cells enhances IM symptoms and promotes EBV-associated tumorigenesis mainly because of a loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Cordycepin enhances Epstein-Barr virus lytic infection and Epstein-Barr virus-positive tumor treatment efficacy by doxorubicin.

PubMed

Du, Yinping; Yu, Jieshi; Du, Li; Tang, Jun; Feng, Wen-Hai

2016-07-01

The consistent latent presence of Epstein-Barr virus (EBV) in tumor cells offers potential for virus-targeted therapies. The switch from the latent form of EBV to the lytic form in tumor cells can lead to tumor cell lysis. In this study, we report that a natural small molecule compound, cordycepin, can induce lytic EBV infection in tumor cells. Subsequently, we demonstrate that cordycepin can enhance EBV reactivating capacity and EBV-positive tumor cell killing ability of low dose doxorubicin. The combination of cordycepin and doxorubicin phosphorylates CCAAT/enhancer binding protein β (C/EBPβ) through protein kinase C (PKC)-p38 mitogen activated protein kinases (p38 MAPK) signaling pathway, and C/EBPβ is required for the activation of lytic EBV infection. Most importantly, an in vivo experiment demonstrates that the combination of cordycepin and doxorubicin is more effective in inhibiting tumor growth in SCID mice than is doxorubicin alone. Our findings establish that cordycepin can enhance the efficacy of conventional chemotherapy for treatment of EBV-positive tumors. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

In vivo dynamics of EBNA1-oriP interaction during latent and lytic replication of Epstein-Barr virus.

PubMed

Daikoku, Tohru; Kudoh, Ayumi; Fujita, Masatoshi; Sugaya, Yutaka; Isomura, Hiroki; Tsurumi, Tatsuya

2004-12-24

The Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) is required for maintenance of the viral genome DNA during the latent phase of EBV replication but continues to be synthesized after the induction of viral productive replication. An EBV genome-wide chromatin immunoprecipitation assay revealed that EBNA1 constantly binds to oriP of the EBV genome during not only latent but also lytic infection. Although the total levels of EBNA1 proved constant throughout the latter, the levels of the oriP-bound form were increased as lytic infection proceeded. EBV productive DNA replication occurs at discrete sites in nuclei, called replication compartments, where viral replication proteins are clustered. Confocal laser microscopic analyses revealed that whereas EBNA1 was distributed broadly in nuclei as fine punctate dots during the latent phase of infection, the protein became redistributed to the viral replication compartments and localized as distinct spots within and/or nearby the compartments after the induction of lytic replication. Taking these findings into consideration, oriP regions of the EBV genome might be organized by EBNA1 into replication domains that may set up scaffolding for lytic replication and transcription.

Dynamic Epstein-Barr Virus Gene Expression on the Path to B-Cell Transformation

PubMed Central

Price, Alexander M.; Luftig, Micah A.

2016-01-01

Epstein-Barr Virus is an oncogenic human herpesvirus in the γ-herpesvirinae sub-family that contains a 170–180 kb double stranded DNA genome. In vivo, EBV commonly infects B and epithelial cells and persists for the life of the host in a latent state in the memory B cell compartment of the peripheral blood. EBV can be reactivated from its latent state leading to increased expression of lytic genes that primarily encode for enzymes necessary to replicate the viral genome as well as structural components of the virion. Lytic cycle proteins also aid in immune evasion, inhibition of apoptosis, and the modulation of other host responses to infection. In vitro, EBV has the potential to infect primary human B cells and induce cellular proliferation to yield effectively immortalized lymphoblastoid cell lines, or LCLs. EBV immortalization of B cells in vitro serves as a model system for studying EBV-mediated lymphomagenesis. While much is known about the steady state viral gene expression within EBV immortalized LCLs and other EBV-positive cell lines, relatively little is known about the early events after primary B-cell infection. It was previously thought that upon latent infection EBV only expressed the well-characterized latency associated transcripts found in LCLs. However, recent work has characterized the early, but transient, expression of lytic genes necessary for efficient transformation as well as delayed responses in the known latency genes. This review summarizes these recent findings that show how dynamic and controlled expression of multiple EBV genes can control the activation of B cells, entry into the cell cycle, inhibition of apoptosis, and control of innate and adaptive immune responses. PMID:24373315

Chloroquine inhibits lytic replication of Kaposi's sarcoma-associated herpesvirus by disrupting mTOR and p38-MAPK activation.

PubMed

Yang, Mengtian; Huang, Lu; Li, Xiaojuan; Kuang, Ersheng

2016-09-01

Lytic infection is essential for the persistent infection and pathogenesis of Kaposi's sarcoma-associated herpesvirus (KSHV), and inhibiting KSHV lytic replication may effectively prevent the occurrence of KSHV-related diseases. Chloroquine (CQ), a well-known antimalarial drug and autophagy inhibitor, exerts broad-spectrum antiviral effects and shows anti-cancer therapeutic potential. However, the ability of CQ and its derivatives to control infection of oncogenic γ-herpesvirus remains undefined. Here we reveal that CQ suppresses KSHV lytic gene expression and virion production, and shows cytotoxicity toward KSHV lytically infected B cells at clinically acceptable doses. CQ suppresses mTOR and p38-MAPK pathway activation during KSHV lytic replication but not latent infection. Furthermore, CQ blocks Epstein-Barr virus (EBV) lytic replication via a distinct mechanism that is invoked to block virion production but does not affect viral gene expression. These results suggest that CQ is an effective antiviral drug against KSHV lytic infection. Our findings indicate that CQ treatment should be considered for controlling KSHV-related diseases, particularly for primary use in co-infection of KSHV with malaria. Copyright © 2016 Elsevier B.V. All rights reserved.

Human Papillomavirus Promotes Epstein-Barr Virus Maintenance and Lytic Reactivation in Immortalized Oral Keratinocytes

PubMed Central

Makielski, Kathleen R.; Lee, Denis; Lorenz, Laurel D.; Nawandar, Dhananjay M.; Chiu, Ya- Fang; Kenney, Shannon C.; Lambert, Paul F.

2016-01-01

Epstein-Barr virus and human papillomaviruses are human tumor viruses that infect and replicate in upper aerodigestive tract epithelia and cause head and neck cancers. The productive phases of both viruses are tied to stratified epithelia highlighting the possibility that these viruses may affect each other’s life cycles. Our lab has established an in vitro model system to test the effects of EBV and HPV co-infection in stratified squamous oral epithelial cells. Our results indicate that HPV increases maintenance of the EBV genome in the co-infected cells and promotes lytic reactivation of EBV in upper layers of stratified epithelium. Expression of the HPV oncogenes E6 and E7 were found to be necessary and sufficient to account for HPV-mediated lytic reactivation of EBV. Our findings indicate that HPV increases the capacity of epithelial cells to support the EBV life cycle, which could in turn increase EBV-mediated pathogenesis in the oral cavity. PMID:27179345

Unique Epstein-Barr virus (EBV) latent gene expression, EBNA promoter usage and EBNA promoter methylation status in chronic active EBV infection.

PubMed

Yoshioka, Mikio; Kikuta, Hideaki; Ishiguro, Nobuhisa; Ma, Xiaoming; Kobayashi, Kunihiko

2003-05-01

Chronic active Epstein-Barr virus infection (CAEBV) has been considered to be a non-neoplastic T-cell lymphoproliferative disease associated with Epstein-Barr virus (EBV) infection. In EBV-associated diseases, the cell phenotype-dependent differences in EBV latent gene expression may reflect the strategy of the virus in relation to latent infection. We previously reported that EBV latent gene expression was restricted; EBV nuclear antigen 1 (EBNA1) transcripts were consistently detected in all spleen samples from five CAEBV patients, but EBNA2 transcripts were detected in only one sample. EBV latent gene expression is controlled by distinct usage of three EBNA promoters (Cp, Wp and Qp). In this study, we examined the EBNA promoter usage by RT-PCR and the methylation status in the Cp and Wp regions using bisulfite PCR analysis in spleen samples from CAEBV patients. EBNA1 transcripts were unexpectedly initiated not from Qp but from Cp in all samples in spite of the restricted form of latency. Furthermore, while Cp was active, Cp was heavily methylated, indicating that CAEBV has unique EBV latent gene expression, EBNA promoter usage and EBNA promoter methylation status, in part due to unique splicing of Cp-initiated transcripts and an activation mechanism in hypermethylated Cp.

Heterogeneous, restricted patterns of Epstein-Barr virus (EBV) latent gene expression in patients with chronic active EBV infection.

PubMed

Yoshioka, M; Ishiguro, N; Ishiko, H; Ma, X; Kikuta, H; Kobayashi, K

2001-10-01

Epstein-Barr virus (EBV) has been shown to infect T lymphocytes and to be associated with a chronic active infection (CAEBV), which has been recognized as a mainly non-neoplastic T-cell lymphoproliferative disorder (T-cell LPD). The systemic distribution of EBV genomes was studied, by real-time PCR, in multiple tissues from six patients with CAEBV, including three patients with T-cell LPD, one patient with B-cell LPD and two patients with undetermined cell-type LPD. There were extremely high loads of EBV genomes in all tissues from the patients. This reflects an abundance of circulating and infiltrating EBV-infected cells and a wide variety of clinical symptoms in the affected tissues. We chose one sample from each patient that was shown by real-time PCR to contain a high load of EBV genomes and examined the expression of EBV latent genes by RT-PCR. EBER1 and EBNA1 transcripts were detected in all samples. Only one sample also expressed EBNA2, LMP1 and LMP2A transcripts in addition to EBER1 and EBNA1 transcripts. Two of the remaining five samples expressed LMP1 and LMP2A transcripts. One sample expressed LMP2A but not LMP1 and EBNA2 transcripts. Another sample expressed EBNA2 but not LMP1 and LMP2A transcripts. The other sample did not express transcripts of any of the other EBNAs or LMPs. None of the samples expressed the viral immediate-early gene BZLF1. These results showed that EBV latent gene expression in CAEBV is heterogeneous and that restricted forms of EBV latency might play a pathogenic role in the development of CAEBV.

Maribavir Inhibits Epstein-Barr Virus Transcription through the EBV Protein Kinase

PubMed Central

Whitehurst, Christopher B.; Sanders, Marcia K.; Law, Mankit; Wang, Fu-Zhang; Xiong, Jie; Dittmer, Dirk P.

2013-01-01

Maribavir (MBV) inhibits Epstein-Barr virus (EBV) replication and the enzymatic activity of the viral protein kinase BGLF4. MBV also inhibits expression of multiple EBV transcripts during EBV lytic infection. Here we demonstrate, with the use of a BGLF4 knockout virus, that effects of MBV on transcription take place primarily through inhibition of BGLF4. MBV inhibits viral genome copy numbers and infectivity to levels similar to and exceeding levels produced by BGLF4 knockout virus. PMID:23449792

[Characterization of BZLF1 gene and its promoter Zp of EBV strains in children with EBV-associated diseases in recent 5 years in Beijing area].

PubMed

Liu, Ya-Li; Ai, Uun-Hong; Yan, Jing; Guan, Xiao-Lei; Liu, Chun-Yan; Xie, Zheng-De

2014-01-01

This study aims to investigate the genetic characteristics of BZLF1 gene and its promoter Zp of the epidemic strains in children with primary Epstein-Barr virus (EBV)-associated diseases. Total DNA was extracted from the peripheral blood of 134 children with EBV-associated infectious mononucleosis (EBV-IM) and 32 children with EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) who were admitted to Beijing Children's Hospital from 2006 to 2011. The EBNA3C, BZLF1, and Zp genes were amplified by PCR assay. Typing of EBV was performed according to the size of the amplification product of EBNA3C gene; the amplification products of BZLF1 and Zp genes were subjected to direct sequencing, and sequence analysis was performed using BioEdit 7. 0. 9. The results were as follows: (1) EBV-1 was present in 140 samples (97.2%, 140/144) and EBV-II in 4 samples (2.8%, 4/144). (2) Three BZLF1 genotypes and their 12 subtypes (including 6 newly found subtypes) were detected in this study; there were no significant differences in the frequencies of BZLF1-A and BZLF1-B between the children with EBV-IM and EBV-HLH (P = 0.083); BZLF1-A1 was the dominant genotype in children with EBV-associated diseases; t BZLF1-A mostly had three 29-bp repeats in the first intron of BZLF1 gene, and BZLF1-B mostly had 30-bp repeats (P = 0.000), with the number of repeats varying from 1 to 13. (3) Four Zp genotypes were detected in this study, including Zp-P, Zp-V3, Zp-V4, and Zp-V1; there were no significant differences in the frequencies of these Zp genotypes between children with EBV-IM and EBV-HLH (P = 0.272, 0.252, 1.0, and 1.0, respectively). (4) The linkage analysis of BZLF1 gene and its promoter Zp showed that BZLF1-A1 was highly associated with Zp-V3 (P = 0.000), while BZLF1-B4 with Zp-P (P = 0.000); EBV-I + BZLF1 A1 was highly associated with Zp-V3 (P = 0.000), while EBV-I+BZLF1-B4 with Zp-P (P = 0.000). The conclusions are as follows: (1) BZLF1-A1 is the dominant genotype in children with

Identification of a Lytic-Cycle Epstein-Barr Virus Gene Product That Can Regulate PKR Activation

PubMed Central

Poppers, Jeremy; Mulvey, Matthew; Perez, Cesar; Khoo, David; Mohr, Ian

2003-01-01

The Epstein-Barr virus (EBV) SM protein is a posttranscriptional regulator of viral gene expression. Like many transactivators encoded by herpesviruses, SM transports predominantly unspliced viral mRNA cargo from the nucleus to the cytosol, where it is subsequently translated. This activity likely involves a region of the protein that has homology to the herpes simplex virus type 1 (HSV-1) ICP27 gene product, the first member of this class of regulators to be discovered. However, SM also contains a repetitive segment rich in arginine and proline residues that is dispensable for its effects on RNA transport and splicing. This portion of SM, comprised of RXP triplet repeats, shows homology to the carboxyl-terminal domain of Us11, a double-stranded RNA (dsRNA) binding protein encoded by HSV-1 that inhibits activation of the cellular PKR kinase. To evaluate the intrinsic ability of SM to regulate PKR, we expressed and purified several SM protein derivatives and examined their activity in a variety of biochemical assays. The full-length SM protein bound dsRNA, associated physically with PKR, and prevented PKR activation. Removal of the 37-residue RXP domain significantly compromised all of these activities. Furthermore, the SM RXP domain was itself sufficient to inhibit PKR activation and interact with the kinase. Relative to its Us11 counterpart, the SM RXP segment bound dsRNA with reduced affinity and responded differently to single-stranded competitor polynucleotides. Thus, SM represents the first EBV gene product expressed during the lytic cycle that can prevent PKR activation. In addition, the RXP repeat segment appears to be a conserved herpesvirus motif capable of associating with dsRNA and modulating activation of the PKR kinase, a molecule important for the control of translation and the cellular antiviral response. PMID:12477828

Identification of a lytic-cycle Epstein-Barr virus gene product that can regulate PKR activation.

PubMed

Poppers, Jeremy; Mulvey, Matthew; Perez, Cesar; Khoo, David; Mohr, Ian

2003-01-01

The Epstein-Barr virus (EBV) SM protein is a posttranscriptional regulator of viral gene expression. Like many transactivators encoded by herpesviruses, SM transports predominantly unspliced viral mRNA cargo from the nucleus to the cytosol, where it is subsequently translated. This activity likely involves a region of the protein that has homology to the herpes simplex virus type 1 (HSV-1) ICP27 gene product, the first member of this class of regulators to be discovered. However, SM also contains a repetitive segment rich in arginine and proline residues that is dispensable for its effects on RNA transport and splicing. This portion of SM, comprised of RXP triplet repeats, shows homology to the carboxyl-terminal domain of Us11, a double-stranded RNA (dsRNA) binding protein encoded by HSV-1 that inhibits activation of the cellular PKR kinase. To evaluate the intrinsic ability of SM to regulate PKR, we expressed and purified several SM protein derivatives and examined their activity in a variety of biochemical assays. The full-length SM protein bound dsRNA, associated physically with PKR, and prevented PKR activation. Removal of the 37-residue RXP domain significantly compromised all of these activities. Furthermore, the SM RXP domain was itself sufficient to inhibit PKR activation and interact with the kinase. Relative to its Us11 counterpart, the SM RXP segment bound dsRNA with reduced affinity and responded differently to single-stranded competitor polynucleotides. Thus, SM represents the first EBV gene product expressed during the lytic cycle that can prevent PKR activation. In addition, the RXP repeat segment appears to be a conserved herpesvirus motif capable of associating with dsRNA and modulating activation of the PKR kinase, a molecule important for the control of translation and the cellular antiviral response.

Epstein-Barr virus lytic infection promotes activation of Toll-like receptor 8 innate immune response in systemic sclerosis monocytes.

PubMed

Farina, Antonella; Peruzzi, Giovanna; Lacconi, Valentina; Lenna, Stefania; Quarta, Silvia; Rosato, Edoardo; Vestri, Anna Rita; York, Michael; Dreyfus, David H; Faggioni, Alberto; Morrone, Stefania; Trojanowska, Maria; Farina, G Alessandra

2017-02-28

Monocytes/macrophages are activated in several autoimmune diseases, including systemic sclerosis (scleroderma; SSc), with increased expression of interferon (IFN)-regulatory genes and inflammatory cytokines, suggesting dysregulation of the innate immune response in autoimmunity. In this study, we investigated whether the lytic form of Epstein-Barr virus (EBV) infection (infectious EBV) is present in scleroderma monocytes and contributes to their activation in SSc. Monocytes were isolated from peripheral blood mononuclear cells (PBMCs) depleted of the CD19+ cell fraction, using CD14/CD16 negative-depletion. Circulating monocytes from SSc and healthy donors (HDs) were infected with EBV. Gene expression of innate immune mediators were evaluated in EBV-infected monocytes from SSc and HDs. Involvement of Toll-like receptor (TLR)8 in viral-mediated TLR8 response was investigated by comparing the TLR8 expression induced by infectious EBV to the expression stimulated by CL075/TLR8/agonist-ligand in the presence of TLR8 inhibitor in THP-1 cells. Infectious EBV strongly induced TLR8 expression in infected SSc and HD monocytes in vitro. Markers of activated monocytes, such as IFN-regulated genes and chemokines, were upregulated in SSc- and HD-EBV-infected monocytes. Inhibiting TLR8 expression reduced virally induced TLR8 in THP-1 infected cells, demonstrating that innate immune activation by infectious EBV is partially dependent on TLR8. Viral mRNA and proteins were detected in freshly isolated SSc monocytes. Microarray analysis substantiated the evidence of an increased IFN signature and altered level of TLR8 expression in SSc monocytes carrying infectious EBV compared to HD monocytes. This study provides the first evidence of infectious EBV in monocytes from patients with SSc and links EBV to the activation of TLR8 and IFN innate immune response in freshly isolated SSc monocytes. This study provides the first evidence of EBV replication activating the TLR8 molecular pathway

Analysis of Epstein-Barr Virus Genomes and Expression Profiles in Gastric Adenocarcinoma.

PubMed

Borozan, Ivan; Zapatka, Marc; Frappier, Lori; Ferretti, Vincent

2018-01-15

Epstein-Barr virus (EBV) is a causative agent of a variety of lymphomas, nasopharyngeal carcinoma (NPC), and ∼9% of gastric carcinomas (GCs). An important question is whether particular EBV variants are more oncogenic than others, but conclusions are currently hampered by the lack of sequenced EBV genomes. Here, we contribute to this question by mining whole-genome sequences of 201 GCs to identify 13 EBV-positive GCs and by assembling 13 new EBV genome sequences, almost doubling the number of available GC-derived EBV genome sequences and providing the first non-Asian EBV genome sequences from GC. Whole-genome sequence comparisons of all EBV isolates sequenced to date (85 from tumors and 57 from healthy individuals) showed that most GC and NPC EBV isolates were closely related although American Caucasian GC samples were more distant, suggesting a geographical component. However, EBV GC isolates were found to contain some consistent changes in protein sequences regardless of geographical origin. In addition, transcriptome data available for eight of the EBV-positive GCs were analyzed to determine which EBV genes are expressed in GC. In addition to the expected latency proteins (EBNA1, LMP1, and LMP2A), specific subsets of lytic genes were consistently expressed that did not reflect a typical lytic or abortive lytic infection, suggesting a novel mechanism of EBV gene regulation in the context of GC. These results are consistent with a model in which a combination of specific latent and lytic EBV proteins promotes tumorigenesis. IMPORTANCE Epstein-Barr virus (EBV) is a widespread virus that causes cancer, including gastric carcinoma (GC), in a small subset of individuals. An important question is whether particular EBV variants are more cancer associated than others, but more EBV sequences are required to address this question. Here, we have generated 13 new EBV genome sequences from GC, almost doubling the number of EBV sequences from GC isolates and providing the

The Missing Link in Epstein-Barr Virus Immune Evasion: the BDLF3 Gene Induces Ubiquitination and Downregulation of Major Histocompatibility Complex Class I (MHC-I) and MHC-II

PubMed Central

Quinn, Laura L.; Williams, Luke R.; White, Claire; Forrest, Calum; Rowe, Martin

2015-01-01

ABSTRACT The ability of Epstein-Barr virus (EBV) to spread and persist in human populations relies on a balance between host immune responses and EBV immune evasion. CD8+ cells specific for EBV late lytic cycle antigens show poor recognition of target cells compared to immediate early and early antigen-specific CD8+ cells. This phenomenon is due in part to the early EBV protein BILF1, whose immunosuppressive activity increases with lytic cycle progression. However, published data suggest the existence of a hitherto unidentified immune evasion protein further enhancing protection against late EBV antigen-specific CD8+ cells. We have now identified the late lytic BDLF3 gene as the missing link accounting for efficient evasion during the late lytic cycle. Interestingly, BDLF3 also contributes to evasion of CD4+ cell responses to EBV. We report that BDLF3 downregulates expression of surface major histocompatibility complex (MHC) class I and class II molecules in the absence of any effect upon other surface molecules screened, including CD54 (ICAM-1) and CD71 (transferrin receptor). BDLF3 both enhanced internalization of surface MHC molecules and reduced the rate of their appearance at the cell surface. The reduced expression of surface MHC molecules correlated with functional protection against CD8+ and CD4+ T cell recognition. The molecular mechanism was identified as BDLF3-induced ubiquitination of MHC molecules and their subsequent downregulation in a proteasome-dependent manner. IMPORTANCE Immune evasion is a necessary feature of viruses that establish lifelong persistent infections in the face of strong immune responses. EBV is an important human pathogen whose immune evasion mechanisms are only partly understood. Of the EBV immune evasion mechanisms identified to date, none could explain why CD8+ T cell responses to late lytic cycle genes are so infrequent and, when present, recognize lytically infected target cells so poorly relative to CD8+ T cells specific for

The Epstein–Barr virus nuclear protein SM is both a post-transcriptional inhibitor and activator of gene expression

PubMed Central

Ruvolo, Vivian; Wang, Eryu; Boyle, Sarah; Swaminathan, Sankar

1998-01-01

The Epstein–Barr virus (EBV) nuclear protein BS-MLF1 (SM) is expressed early after entry of EBV into the lytic cycle. SM transactivates reporter gene constructs driven by a wide variety of promoters, but the mechanism of SM action is poorly understood. In this study, we demonstrate that the SM protein inhibits expression of intron-containing genes and activates expression of intron-less genes. We demonstrate that SM has the predicted inhibitory effect on expression of a spliced EBV gene but activates an unspliced early EBV gene. SM inhibited gene expression at the post-transcriptional level by preventing the accumulation of nuclear and cytoplasmic RNA transcripts. Conversely, SM led to increased accumulation of nuclear mRNA from intron-less genes without affecting the rate of transcription, indicating that SM enhances nuclear RNA stability. The ratio of cytoplasmic to nuclear polyadenylated mRNA was increased in the presence of SM, suggesting that SM also enhances nucleo-cytoplasmic mRNA transport. The degree of transactivation by SM was dependent on the sequence of the 3′-untranslated region of the target mRNA. Finally, we demonstrate that the amino-terminal portion of SM fused to glutathione-S-transferase binds radioactively labeled RNA in vitro, indicating that SM is a single-stranded RNA binding protein. Importantly, the latent and immediate-early genes of EBV contain introns whereas many early and late genes do not. Thus, SM may down-regulate synthesis of host cell proteins and latent EBV proteins while simultaneously enhancing expression of specific lytic EBV genes by binding to mRNA and modulating its stability and transport. PMID:9671768

The Epstein-Barr virus nuclear protein SM is both a post-transcriptional inhibitor and activator of gene expression.

PubMed

Ruvolo, V; Wang, E; Boyle, S; Swaminathan, S

1998-07-21

The Epstein-Barr virus (EBV) nuclear protein BS-MLF1 (SM) is expressed early after entry of EBV into the lytic cycle. SM transactivates reporter gene constructs driven by a wide variety of promoters, but the mechanism of SM action is poorly understood. In this study, we demonstrate that the SM protein inhibits expression of intron-containing genes and activates expression of intron-less genes. We demonstrate that SM has the predicted inhibitory effect on expression of a spliced EBV gene but activates an unspliced early EBV gene. SM inhibited gene expression at the post-transcriptional level by preventing the accumulation of nuclear and cytoplasmic RNA transcripts. Conversely, SM led to increased accumulation of nuclear mRNA from intron-less genes without affecting the rate of transcription, indicating that SM enhances nuclear RNA stability. The ratio of cytoplasmic to nuclear polyadenylated mRNA was increased in the presence of SM, suggesting that SM also enhances nucleo-cytoplasmic mRNA transport. The degree of transactivation by SM was dependent on the sequence of the 3'-untranslated region of the target mRNA. Finally, we demonstrate that the amino-terminal portion of SM fused to glutathione-S-transferase binds radioactively labeled RNA in vitro, indicating that SM is a single-stranded RNA binding protein. Importantly, the latent and immediate-early genes of EBV contain introns whereas many early and late genes do not. Thus, SM may down-regulate synthesis of host cell proteins and latent EBV proteins while simultaneously enhancing expression of specific lytic EBV genes by binding to mRNA and modulating its stability and transport.

Productive infection of Epstein-Barr virus (EBV) in EBV-genome-positive epithelial cell lines (GT38 and GT39) derived from gastric tissues.

PubMed

Takasaka, N; Tajima, M; Okinaga, K; Satoh, Y; Hoshikawa, Y; Katsumoto, T; Kurata, T; Sairenji, T

1998-08-01

We characterized the expression of Epstein-Barr virus (EBV) on two epithelial cell lines, GT38 and GT39, derived from human gastric tissues. The EBV nuclear antigen (EBNA) was detected in all cells of both cell lines. The EBV immediate-early BZLF 1 protein (ZEBRA), the early antigen diffuse component (EA-D), and one of the EBV envelope proteins (gp350/220) were expressed spontaneously in small proportions in the cells. EBNA 1, EBNA2, latent membrane protein 1, ZEBRA, and EA-D molecules were then observed by Western blotting in the cells. The lytic cycle was enhanced with treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA) or n-butyrate. The virus particles were observed in the TPA treated GT38 cells by electron microscopy. Infectious EBV was detected with the transformation of cord blood lymphocytes and also with the induction of early antigen to Raji cells by the supernatants of both cells lines. A major single and minor multiple fused terminal fragments and a ladder of smaller fragments of the EBV genome were detected with a Xhol probe in both cell lines. These epithelial cells lines and viruses will be useful in studying their association with EBV in gastric epithelial cells.

The Missing Link in Epstein-Barr Virus Immune Evasion: the BDLF3 Gene Induces Ubiquitination and Downregulation of Major Histocompatibility Complex Class I (MHC-I) and MHC-II.

PubMed

Quinn, Laura L; Williams, Luke R; White, Claire; Forrest, Calum; Zuo, Jianmin; Rowe, Martin

2016-01-01

The ability of Epstein-Barr virus (EBV) to spread and persist in human populations relies on a balance between host immune responses and EBV immune evasion. CD8(+) cells specific for EBV late lytic cycle antigens show poor recognition of target cells compared to immediate early and early antigen-specific CD8(+) cells. This phenomenon is due in part to the early EBV protein BILF1, whose immunosuppressive activity increases with lytic cycle progression. However, published data suggest the existence of a hitherto unidentified immune evasion protein further enhancing protection against late EBV antigen-specific CD8(+) cells. We have now identified the late lytic BDLF3 gene as the missing link accounting for efficient evasion during the late lytic cycle. Interestingly, BDLF3 also contributes to evasion of CD4(+) cell responses to EBV. We report that BDLF3 downregulates expression of surface major histocompatibility complex (MHC) class I and class II molecules in the absence of any effect upon other surface molecules screened, including CD54 (ICAM-1) and CD71 (transferrin receptor). BDLF3 both enhanced internalization of surface MHC molecules and reduced the rate of their appearance at the cell surface. The reduced expression of surface MHC molecules correlated with functional protection against CD8(+) and CD4(+) T cell recognition. The molecular mechanism was identified as BDLF3-induced ubiquitination of MHC molecules and their subsequent downregulation in a proteasome-dependent manner. Immune evasion is a necessary feature of viruses that establish lifelong persistent infections in the face of strong immune responses. EBV is an important human pathogen whose immune evasion mechanisms are only partly understood. Of the EBV immune evasion mechanisms identified to date, none could explain why CD8(+) T cell responses to late lytic cycle genes are so infrequent and, when present, recognize lytically infected target cells so poorly relative to CD8(+) T cells specific for

Immediate-Early Transactivator Rta of Epstein-Barr Virus (EBV) Shows Multiple Epitopes Recognized by EBV-Specific Cytotoxic T Lymphocytes

PubMed Central

Pepperl, Sandra; Benninger-Döring, Gerlinde; Modrow, Susanne; Wolf, Hans; Jilg, Wolfgang

1998-01-01

We analyzed the immediate-early transactivator Rta of Epstein-Barr virus (EBV) for its role as a target for specific cytotoxic T lymphocytes (CTL). Panels of overlapping peptides covering the entire amino acid sequence of Rta were synthesized and used to induce and analyze specific CTL responses in EBV-positive donors. Using peptide-pulsed target cells, we found nine different CTL epitopes that are distributed over the entire protein sequence. One epitope restricted by HLA-A24 could be mapped to the decameric sequence DYCNVLNKEF between amino acid positions 28 and 37 of the Rta protein. A second epitope could be assigned to the same region of Rta (residues 25 to 39) and was shown to be restricted by HLA-B18. Another, minimal epitope could be mapped to the nonameric sequence ATIGTAMYK between amino acid positions 134 and 142; this peptide was restricted by HLA-A11. Another four epitopes were proven to be restricted by HLA-A2, -A3, -B61, and -Cw4 and were located between Rta residues 225 and 239, 145 and 159, 529 and 543, and 393 and 407, respectively. For two other epitopes, only the location within the Rta protein is known so far (residues 121 to 135 and 441 to 455); their exact HLA restriction patterns have not yet been identified. Using target cells infected with recombinant vaccinia virus containing the gene for Rta, we showed that six of eight Rta-specific CTL lines recognized the corresponding peptides also after endogenous processing. These data suggest that Rta comprises an important target for EBV-specific cellular cytotoxicity. Together with recent findings of other immediate-early and early proteins also acting as CTL targets, they reveal the role of proteins of the lytic cycle in the immune recognition of EBV-infected cells. PMID:9765404

EBV-driven B-cell lymphoproliferative disorders: from biology, classification and differential diagnosis to clinical management

PubMed Central

Ok, Chi Young; Li, Ling; Young, Ken H

2015-01-01

Epstein–Barr virus (EBV) is a ubiquitous herpesvirus, affecting >90% of the adult population. EBV targets B-lymphocytes and achieves latent infection in a circular episomal form. Different latency patterns are recognized based on latent gene expression pattern. Latent membrane protein-1 (LMP-1) mimics CD40 and, when self-aggregated, provides a proliferation signal via activating the nuclear factor-kappa B, Janus kinase/signal transducer and activator of transcription, phosphoinositide 3-kinase/Akt (PI3K/Akt) and mitogen-activated protein kinase pathways to promote cellular proliferation. LMP-1 also induces BCL-2 to escape from apoptosis and gives a signal for cell cycle progression by enhancing cyclin-dependent kinase 2 and phosphorylation of retinoblastoma (Rb) protein and by inhibiting p16 and p27. LMP-2A blocks the surface immunoglobulin-mediated lytic cycle reactivation. It also activates the Ras/PI3K/Akt pathway and induces Bcl-xL expression to promote B-cell survival. Recent studies have shown that ebv-microRNAs can provide extra signals for cellular proliferation, cell cycle progression and anti-apoptosis. EBV is well known for association with various types of B-lymphocyte, T-lymphocyte, epithelial cell and mesenchymal cell neoplasms. B-cell lymphoproliferative disorders encompass a broad spectrum of diseases, from benign to malignant. Here we review our current understanding of EBV-induced lymphomagenesis and focus on biology, diagnosis and management of EBV-associated B-cell lymphoproliferative disorders. PMID:25613729

Delta-9 tetrahydrocannabinol (THC) inhibits lytic replication of gamma oncogenic herpesviruses in vitro.

PubMed

Medveczky, Maria M; Sherwood, Tracy A; Klein, Thomas W; Friedman, Herman; Medveczky, Peter G

2004-09-15

The major psychoactive cannabinoid compound of marijuana, delta-9 tetrahydrocannabinol (THC), has been shown to modulate immune responses and lymphocyte function. After primary infection the viral DNA genome of gamma herpesviruses persists in lymphoid cell nuclei in a latent episomal circular form. In response to extracellular signals, the latent virus can be activated, which leads to production of infectious virus progeny. Therefore, we evaluated the potential effects of THC on gamma herpesvirus replication. Tissue cultures infected with various gamma herpesviruses were cultured in the presence of increasing concentrations of THC and the amount of viral DNA or infectious virus yield was compared to those of control cultures. The effect of THC on Kaposi's Sarcoma Associated Herpesvirus (KSHV) and Epstein-Barr virus (EBV) replication was measured by the Gardella method and replication of herpesvirus saimiri (HVS) of monkeys, murine gamma herpesvirus 68 (MHV 68), and herpes simplex type 1 (HSV-1) was measured by yield reduction assays. Inhibition of the immediate early ORF 50 gene promoter activity was measured by the dual luciferase method. Micromolar concentrations of THC inhibit KSHV and EBV reactivation in virus infected/immortalized B cells. THC also strongly inhibits lytic replication of MHV 68 and HVS in vitro. Importantly, concentrations of THC that inhibit virus replication of gamma herpesviruses have no effect on cell growth or HSV-1 replication, indicating selectivity. THC was shown to selectively inhibit the immediate early ORF 50 gene promoter of KSHV and MHV 68. THC specifically targets viral and/or cellular mechanisms required for replication and possibly shared by these gamma herpesviruses, and the endocannabinoid system is possibly involved in regulating gamma herpesvirus latency and lytic replication. The immediate early gene ORF 50 promoter activity was specifically inhibited by THC. These studies may also provide the foundation for the development

Plasma EBV microRNAs in paediatric renal transplant recipients.

PubMed

Hassan, Jaythoon; Dean, Jonathan; De Gascun, Cillian F; Riordan, Michael; Sweeney, Clodagh; Connell, Jeff; Awan, Atif

2018-06-01

Epstein-Barr virus (EBV) was the first human virus identified to express microRNA (miRNA). To date, 44 mature miRNAs are encoded for within the EBV genome. EBV miRNAs have not been profiled in paediatric renal transplant recipients. In this study, we investigated circulating EBV miRNA profiles as novel biomarkers in paediatric renal transplant patients. Forty-two microRNAs encoded within 2 EBV open reading frames (BART and BHRF) were examined in renal transplant recipients who resolved EBV infection (REI) or maintained chronic high viral loads (CHL), and in non-transplant patients with acute infectious mononucleosis (IM). Plasma EBV-miR-BART2-5p was present in higher numbers of IM (7/8) and CHL (7/10) compared to REI (7/12) patients. A trend was observed between the numbers of plasma EBV miRNAs expressed and EBV viral load (p < 0.07). Several EBV-miRs including BART7-3p, 15, 9-3p, 11-3p, 1-3p and 3-3p were detected in IM and CHL patients only. The lytic EBV-miRs, BHRF1-2-3p and 1-1, indicating active viral replication, were detected in IM patients only. One CHL patient developed post-transplant lymphoproliferative disease (PTLD) after several years and analysis of 10 samples over a 30-month period showed an average 24-fold higher change in plasma EBV-miR-BART2-5p compared to the CHL group and 110-fold higher change compared to the REI group. Our results suggest that EBV-miR-BART2-5p, which targets the stress-induced immune ligand MICB to escape recognition and elimination by NK cells, may have a role in sustaining high EBV viral loads in CHL paediatric kidney transplant recipients.

The B-Cell Specific Transcription Factor, Oct-2, Promotes Epstein-Barr Virus Latency by Inhibiting the Viral Immediate-Early Protein, BZLF1

PubMed Central

Robinson, Amanda R.; Kwek, Swee Sen; Kenney, Shannon C.

2012-01-01

The Epstein-Barr virus (EBV) latent-lytic switch is mediated by the BZLF1 immediate-early protein. EBV is normally latent in memory B cells, but cellular factors which promote viral latency specifically in B cells have not been identified. In this report, we demonstrate that the B-cell specific transcription factor, Oct-2, inhibits the function of the viral immediate-early protein, BZLF1, and prevents lytic viral reactivation. Co-transfected Oct-2 reduces the ability of BZLF1 to activate lytic gene expression in two different latently infected nasopharyngeal carcinoma cell lines. Furthermore, Oct-2 inhibits BZLF1 activation of lytic EBV promoters in reporter gene assays, and attenuates BZLF1 binding to lytic viral promoters in vivo. Oct-2 interacts directly with BZLF1, and this interaction requires the DNA-binding/dimerization domain of BZLF1 and the POU domain of Oct-2. An Oct-2 mutant (Δ262–302) deficient for interaction with BZLF1 is unable to inhibit BZLF1-mediated lytic reactivation. However, an Oct-2 mutant defective for DNA-binding (Q221A) retains the ability to inhibit BZLF1 transcriptional effects and DNA-binding. Importantly, shRNA-mediated knockdown of endogenous Oct-2 expression in several EBV-positive Burkitt lymphoma and lymphoblastoid cell lines increases the level of lytic EBV gene expression, while decreasing EBNA1 expression. Moreover, treatments which induce EBV lytic reactivation, such as anti-IgG cross-linking and chemical inducers, also decrease the level of Oct-2 protein expression at the transcriptional level. We conclude that Oct-2 potentiates establishment of EBV latency in B cells. PMID:22346751

EBV-encoded miRNAs target ATM-mediated response in nasopharyngeal carcinoma.

PubMed

Lung, Raymond W-M; Hau, Pok-Man; Yu, Ken H-O; Yip, Kevin Y; Tong, Joanna H-M; Chak, Wing-Po; Chan, Anthony W-H; Lam, Ka-Hei; Lo, Angela Kwok-Fung; Tin, Edith K-Y; Chau, Shuk-Ling; Pang, Jesse C-S; Kwan, Johnny S-H; Busson, Pierre; Young, Lawrence S; Yap, Lee-Fah; Tsao, Sai-Wah; To, Ka-Fai; Lo, Kwok-Wai

2018-04-01

Nasopharyngeal carcinoma (NPC) is a highly invasive epithelial malignancy that is prevalent in southern China and Southeast Asia. It is consistently associated with latent Epstein-Barr virus (EBV) infection. In NPC, miR-BARTs, the EBV-encoded miRNAs derived from BamH1-A rightward transcripts, are abundantly expressed and contribute to cancer development by targeting various cellular and viral genes. In this study, we establish a comprehensive transcriptional profile of EBV-encoded miRNAs in a panel of NPC patient-derived xenografts and an EBV-positive NPC cell line by small RNA sequencing. Among the 40 miR-BARTs, predominant expression of 22 miRNAs was consistently detected in these tumors. Among the abundantly expressed EBV-miRNAs, BART5-5p, BART7-3p, BART9-3p, and BART14-3p could negatively regulate the expression of a key DNA double-strand break (DSB) repair gene, ataxia telangiectasia mutated (ATM), by binding to multiple sites on its 3'-UTR. Notably, the expression of these four miR-BARTs represented more than 10% of all EBV-encoded miRNAs in tumor cells, while downregulation of ATM expression was commonly detected in all of our tested sequenced samples. In addition, downregulation of ATM was also observed in primary NPC tissues in both qRT-PCR (16 NP and 45 NPC cases) and immunohistochemical staining (35 NP and 46 NPC cases) analysis. Modulation of ATM expression by BART5-5p, BART7-3p, BART9-3p, and BART14-3p was demonstrated in the transient transfection assays. These findings suggest that EBV uses miRNA machinery as a key mechanism to control the ATM signaling pathway in NPC cells. By suppressing these endogenous miR-BARTs in EBV-positive NPC cells, we further demonstrated the novel function of miR-BARTs in inhibiting Zta-induced lytic reactivation. These findings imply that the four viral miRNAs work co-operatively to modulate ATM activity in response to DNA damage and to maintain viral latency, contributing to the tumorigenesis of NPC. © 2017 The Authors

Differential cellular targets of Epstein-Barr virus (EBV) infection between acute EBV-associated hemophagocytic lymphohistiocytosis and chronic active EBV infection.

PubMed

Kasahara, Y; Yachie, A; Takei, K; Kanegane, C; Okada, K; Ohta, K; Seki, H; Igarashi, N; Maruhashi, K; Katayama, K; Katoh, E; Terao, G; Sakiyama, Y; Koizumi, S

2001-09-15

Unusual Epstein-Barr virus (EBV) infection into T or natural killer cells plays a pivotal role in the pathogenesis of acute EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) and chronic active EBV infection (CAEBV). The precise frequency and localization of EBV genome in lymphocyte subpopulations especially within T-cell subpopulations are unclear in these EBV-related disorders. This study analyzed the frequency of EBV-infected cells in circulating lymphocyte subpopulations from 4 patients with acute EBV-HLH and 4 with CAEBV. EBV- encoded small RNA-1 in situ hybridization examination of peripheral blood lymphocytes showed a significantly higher frequency of EBV-infected cells of 1.0% to 13.4% in EBV-HLH and 1.6% to 25.6% in CAEBV, respectively. The patterns of EBV infection in lymphocyte subpopulations were quite different between acute EBV-HLH and CAEBV. EBV infection was predominant in CD8(+) T cells in all EBV-HLH patients, whereas the dominant EBV-infected cell populations were non-CD8(+) lymphocyte subpopulations in CAEBV patients. Phenotypical analysis revealed that EBV-infected cell populations from both EBV-HLH and CAEBV were activated. There was no predominance of any EBV substrain of latent membrane protein-1, EBV-associated nuclear antigen (EBNA)-1, and EBNA-2 genes between the 2 abnormal EBV-associated disorders, and self-limited acute infectious mononucleosis. These results showing differential virus-cell interactions between acute EBV-HLH and CAEBV indicated different pathogenic mechanisms against EBV infection between the 2 EBV-associated diseases, which accounts for the difference in clinical manifestations between the 2 diseases.

Epstein-Barr Virus (EBV) Latent Protein EBNA3A Directly Targets and Silences the STK39 Gene in B Cells Infected by EBV.

PubMed

Bazot, Quentin; Paschos, Kostas; Allday, Martin J

2018-04-01

Epstein-Barr virus (EBV) establishes latent infection in human B cells and is associated with a wide range of cancers. The EBV nuclear antigen 3 (EBNA3) family proteins are critical for B cell transformation and function as transcriptional regulators. It is well established that EBNA3A and EBNA3C cooperate in the regulation of cellular genes. Here, we demonstrate that the gene STK39 is repressed only by EBNA3A. This is the first example of a gene regulated only by EBNA3A in EBV-transformed lymphoblastoid cell lines (LCLs) without the help of EBNA3C. This was demonstrated using a variety of LCLs carrying either knockout, revertant, or conditional EBNA3 recombinants. Investigating the kinetics of EBNA3A-mediated changes in STK39 expression showed that STK39 becomes derepressed quickly after EBNA3A inactivation. This derepression is reversible as EBNA3A reactivation represses STK39 in the same cells expressing a conditional EBNA3A. STK39 is silenced shortly after primary B cell infection by EBV, and no STK39 -encoded protein (SPAK) is detected 3 weeks postinfection. Chromatin immunoprecipitation (ChIP) analysis indicates that EBNA3A directly binds to a regulatory region downstream of the STK39 transcription start site. For the first time, we demonstrated that the polycomb repressive complex 2 with the deposition of the repressive mark H3K27me3 is not only important for the maintenance of an EBNA3A target gene ( STK39 ) but is also essential for the initial establishment of its silencing. Finally, we showed that DNA methyltransferases are involved in the EBNA3A-mediated repression of STK39 IMPORTANCE EBV is well known for its ability to transform B lymphocytes to continuously proliferating lymphoblastoid cell lines. This is achieved in part by the reprogramming of cellular gene transcription by EBV transcription factors, including the EBNA3 proteins that play a crucial role in this process. In the present study, we found that EBNA3A epigenetically silences STK39 This

Inhibition of Epstein-Barr virus reactivation by the flavonoid apigenin.

PubMed

Wu, Chung-Chun; Fang, Chih-Yeu; Cheng, Yu-Jhen; Hsu, Hui-Yu; Chou, Sheng-Ping; Huang, Sheng-Yen; Tsai, Ching-Hwa; Chen, Jen-Yang

2017-01-05

Lytic reactivation of EBV has been reported to play an important role in human diseases, including NPC carcinogenesis. Inhibition of EBV reactivation is considered to be of great benefit in the treatment of virus-associated diseases. For this purpose, we screened for inhibitory compounds and found that apigenin, a flavonoid, seemed to have the ability to inhibit EBV reactivation. We performed western blotting, immunofluorescence and luciferase analyses to determine whether apigenin has anti-EBV activity. Apigenin inhibited expression of the EBV lytic proteins, Zta, Rta, EAD and DNase in epithelial and B cells. It also reduced the number of EBV-reactivating cells detectable by immunofluorescence analysis. In addition, apigenin has been found to reduce dramatically the production of EBV virions. Luciferase reporter analysis was performed to determine the mechanism by which apigenin inhibits EBV reactivation: apigenin suppressed the activity of the immediate-early (IE) gene Zta and Rta promoters, suggesting it can block initiation of the EBV lytic cycle. Taken together, apigenin inhibits EBV reactivation by suppressing the promoter activities of two viral IE genes, suggesting apigenin is a potential dietary compound for prevention of EBV reactivation.

Resistance gene transfer: induction of transducing phage by sub-inhibitory concentrations of antimicrobials is not correlated to induction of lytic phage

PubMed Central

Stanczak-Mrozek, Kinga I.; Laing, Ken G.

2017-01-01

Objectives: Horizontal gene transfer of antimicrobial resistance (AMR) genes between clinical isolates via transduction is poorly understood. MRSA are opportunistic pathogens resistant to all classes of antimicrobial agents but currently no strains are fully drug resistant. AMR gene transfer between Staphylococcus aureus isolates is predominantly due to generalized transduction via endogenous bacteriophage, and recent studies have suggested transfer is elevated during host colonization. The aim was to investigate whether exposure to sub-MIC concentrations of antimicrobials triggers bacteriophage induction and/or increased efficiency of AMR gene transfer. Methods: Isolates from MRSA carriers were exposed to nine antimicrobials and supernatants were compared for lytic phage particles and ability to transfer an AMR gene. A new technology, droplet digital PCR, was used to measure the concentration of genes in phage particles. Results: All antibiotics tested induced lytic phage and AMR gene transduction, although the ratio of transducing particles to lytic particles differed substantially for each antibiotic. Mupirocin induced the highest ratio of transducing versus lytic particles. Gentamicin and novobiocin reduced UV-induced AMR transduction. The genes carried in phage particles correlated with AMR transfer or lytic particle activity, suggesting antimicrobials influence which DNA sequences are packaged into phage particles. Conclusions: Sub-inhibitory antibiotics induce AMR gene transfer between clinical MRSA, while combination therapy with an inhibiting antibiotic could potentially alter AMR gene packaging into phage particles, reducing AMR transfer. In a continually evolving environment, pathogens have an advantage if they can transfer DNA while lowering the risk of lytic death. PMID:28369562

Chaetocin reactivates the lytic replication of Epstein-Barr virus from latency via reactive oxygen species.

PubMed

Zhang, Shilun; Yin, Juan; Zhong, Jiang

2017-01-01

Oxidative stress, regarded as a negative effect of free radicals in vivo, takes place when organisms suffer from harmful stimuli. Some viruses can induce the release of reactive oxygen species (ROS) in infected cells, which may be closely related with their pathogenicity. In this report, chaetocin, a fungal metabolite reported to have antimicrobial and cytostatic activity, was studied for its effect on the activation of latent Epstein-Barr virus (EBV) in B95-8 cells. We found that chaetocin remarkably up-regulated EBV lytic transcription and DNA replication at a low concentration (50 nmol L -1 ). The activation of latent EBV was accompanied by an increased cellular ROS level. N-acetyl-L-cysteine (NAC), an ROS inhibitor, suppressed chaetocin-induced EBV activation. Chaetocin had little effect on histone H3K9 methylation, while NAC also significantly reduced H3K9 methylation. These results suggested that chaetocin reactivates latent EBV primarily via ROS pathways.

Epstein-Barr Virus (EBV)-associated Gastric Carcinoma

PubMed Central

Iizasa, Hisashi; Nanbo, Asuka; Nishikawa, Jun; Jinushi, Masahisa; Yoshiyama, Hironori

2012-01-01

The ubiquitous Epstein-Barr virus (EBV) is associated with several human tumors, which include lymphoid and epithelial malignancies. It is known that EBV persistently infects the memory B cell pool of healthy individuals by activating growth and survival signaling pathways that can contribute to B cell lymphomagenesis. Although the monoclonal proliferation of EBV-infected cells can be observed in epithelial tumors, such as nasopharyngeal carcinoma and EBV-associated gastric carcinoma, the precise role of EBV in the carcinogenic progress is not fully understood. This review features characteristics and current understanding of EBV-associated gastric carcinoma. EBV-associated gastric carcinoma comprises almost 10% of all gastric carcinoma cases and expresses restricted EBV latent genes (Latency I). Firstly, definition, epidemiology, and clinical features are discussed. Then, the route of infection and carcinogenic role of viral genes are presented. Of particular interest, the association with frequent genomic CpG methylation and role of miRNA for carcinogenesis are topically discussed. Finally, the possibility of therapies targeting EBV-associated gastric carcinoma is proposed. PMID:23342366

Characterization of variants in the promoter of BZLF1 gene of EBV in nonmalignant EBV-associated diseases in Chinese children.

PubMed

Jin, Yingkang; Xie, Zhengde; Lu, Gen; Yang, Shuang; Shen, Kunling

2010-05-10

Diseases associated with Epstein-Barr virus (EBV) infections, such as infectious mononucleosis (IM), EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) and chronic active EBV infection (CAEBV) are not rare in Chinese children. The association of type 1 or type 2 EBV and variants of the EBV BZLF1 promoter zone (Zp) with these diseases is unclear. The objective of this study was to investigate the relationship between EBV genotypes (Zp variants and EBV type 1 and 2) and the clinical phenotypes of EBV-associated diseases in Chinese children. The Zp region was directly sequenced in 206 EBV-positive DNA samples from the blood of patients with IM, EBV-HLH, CAEBV, and healthy controls. Type 1 or type 2 EBV was examined by PCR for EBNA2 and EBNA3C subtypes. Four polymorphic Zp variants were identified: Zp-P, Zp-V3, Zp-P4 and Zp-V1, a new variant. The Zp-V3 variant was significantly associated with CAEBV (P EBV-HLH, compared with IM and healthy controls, mostly as Zp-P+V3 co-infection. Type 1 EBV was predominant in all categories (81.3-95%) and there was no significant difference in the frequency of the EBV types 1 and 2 in different categories (P > 0.05). Type 1 EBV and BZLF1 Zp-P of EBV were the predominant genotypes in nonmalignant EBV associated diseases in Chinese children and Zp-V3 variant may correlates with the developing of severe EBV infection diseases, such as CAEBV and EBV-HLH.

Characterization of variants in the promoter of BZLF1 gene of EBV in nonmalignant EBV-associated diseases in Chinese children

PubMed Central

2010-01-01

Background Diseases associated with Epstein-Barr virus (EBV) infections, such as infectious mononucleosis (IM), EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) and chronic active EBV infection (CAEBV) are not rare in Chinese children. The association of type 1 or type 2 EBV and variants of the EBV BZLF1 promoter zone (Zp) with these diseases is unclear. Results The objective of this study was to investigate the relationship between EBV genotypes (Zp variants and EBV type 1 and 2) and the clinical phenotypes of EBV-associated diseases in Chinese children. The Zp region was directly sequenced in 206 EBV-positive DNA samples from the blood of patients with IM, EBV-HLH, CAEBV, and healthy controls. Type 1 or type 2 EBV was examined by PCR for EBNA2 and EBNA3C subtypes. Four polymorphic Zp variants were identified: Zp-P, Zp-V3, Zp-P4 and Zp-V1, a new variant. The Zp-V3 variant was significantly associated with CAEBV (P ≤ 0.01). The frequency of co-infection with Zp variants was higher in patients with CAEBV and EBV-HLH, compared with IM and healthy controls, mostly as Zp-P+V3 co-infection. Type 1 EBV was predominant in all categories (81.3-95%) and there was no significant difference in the frequency of the EBV types 1 and 2 in different categories (P > 0.05). Conclusions Type 1 EBV and BZLF1 Zp-P of EBV were the predominant genotypes in nonmalignant EBV associated diseases in Chinese children and Zp-V3 variant may correlates with the developing of severe EBV infection diseases, such as CAEBV and EBV-HLH. PMID:20459737

Latency of Epstein-Barr virus is stabilized by antisense-mediated control of the viral immediate-early gene BZLF-1.

PubMed

Prang, N; Wolf, H; Schwarzmann, F

1999-12-01

The ability of the Epstein-Barr virus (EBV) to avoid lytic replication and to establish a latent infection in B-lymphocytes is fundamental for its lifelong persistence and the pathogenesis of various EBV-associated diseases. The viral immediate-early gene BZLF-1 plays a key role for the induction of lytic replication and its activity is strictly regulated on different levels of gene expression. Recently, it was demonstrated that BZLF-1 is also controlled by a posttranscriptional mechanism. Transient synthesis of a mutated competitor RNA saturated this mechanism and caused both expression of the BZLF-1 protein and the induction of lytic viral replication. Using short overlapping fragments of the competitor, it is shown that this control acts on the unspliced primary transcript. RT-PCR demonstrated unspliced BZLF-1 RNA in latently infected B-lymphocytes in the absence of BZLF-1 protein. Due to the complementarity of the gene BZLF-1 and the latency-associated gene EBNA-1 on the opposite strand of the genome, we propose an antisense-mediated mechanism. RNase protection assays demonstrated transcripts in antisense orientation to the BZLF-1 transcript during latency, which comprise a comparable constellation to other herpesviruses. A combined RNAse protection/RT-PCR assay detected the double-stranded hybrid RNA, consisting of the unspliced BZLF-1 transcript and a noncoding intron of the EBNA-1 gene. Binding of BZLF-1 transcripts is suggested to be an important backup control mechanism in addition to transcriptional regulation, stabilizing latency and preventing inappropriate lytic viral replication in vivo. Copyright 1999 Wiley-Liss, Inc.

A Role for the Nucleosome Assembly Proteins TAF-Iβ and NAP1 in the Activation of BZLF1 Expression and Epstein-Barr Virus Reactivation

PubMed Central

Frappier, Lori

2013-01-01

The reactivation of Epstein-Barr virus (EBV) from latent to lytic infection begins with the expression of the viral BZLF1 gene, leading to a subsequent cascade of viral gene expression and amplification of the EBV genome. Using RNA interference, we show that nucleosome assembly proteins NAP1 and TAF-I positively contribute to EBV reactivation in epithelial cells through the induction of BZLF1 expression. In addition, overexpression of NAP1 or the β isoform of TAF-I (TAF-Iβ) in AGS cells latently infected with EBV was sufficient to induce BZLF1 expression. Chromatin immunoprecipitation experiments performed in AGS-EBV cells showed that TAF-I associated with the BZLF1 promoter upon lytic induction and affected local histone modifications by increasing H3K4 dimethylation and H4K8 acetylation. MLL1, the host protein known to dimethylate H3K4, was found to associate with the BZLF1 promoter upon lytic induction in a TAF-I-dependent manner, and MLL1 depletion decreased BZLF1 expression, confirming its contribution to lytic reactivation. The results indicate that TAF-Iβ promotes BZLF1 expression and subsequent lytic infection by affecting chromatin at the BZLF1 promoter. PMID:23691099

A role for the nucleosome assembly proteins TAF-Iβ and NAP1 in the activation of BZLF1 expression and Epstein-Barr virus reactivation.

PubMed

Mansouri, Sheila; Wang, Shan; Frappier, Lori

2013-01-01

The reactivation of Epstein-Barr virus (EBV) from latent to lytic infection begins with the expression of the viral BZLF1 gene, leading to a subsequent cascade of viral gene expression and amplification of the EBV genome. Using RNA interference, we show that nucleosome assembly proteins NAP1 and TAF-I positively contribute to EBV reactivation in epithelial cells through the induction of BZLF1 expression. In addition, overexpression of NAP1 or the β isoform of TAF-I (TAF-Iβ) in AGS cells latently infected with EBV was sufficient to induce BZLF1 expression. Chromatin immunoprecipitation experiments performed in AGS-EBV cells showed that TAF-I associated with the BZLF1 promoter upon lytic induction and affected local histone modifications by increasing H3K4 dimethylation and H4K8 acetylation. MLL1, the host protein known to dimethylate H3K4, was found to associate with the BZLF1 promoter upon lytic induction in a TAF-I-dependent manner, and MLL1 depletion decreased BZLF1 expression, confirming its contribution to lytic reactivation. The results indicate that TAF-Iβ promotes BZLF1 expression and subsequent lytic infection by affecting chromatin at the BZLF1 promoter.

High frequency of EBV association and 30-bp deletion in the LMP-1 gene in CD56 lymphomas of the upper aerodigestive tract.

PubMed

Tai, Yan-Chin; Kim, Lian-Hua; Peh, Suat-Cheng

2004-03-01

Natural killer (NK)/T-cell lymphomas are frequently associated with Epstein-Barr virus (EBV), and usually lack TCR gene rearrangement. Studies from Asia have reported frequent deletion in the LMP-1 gene in EBV-associated nasopharyngeal carcinoma (NPC). The present study aims to investigate LMP-1 and TCRgamma gene status in upper aerodigestive tract lymphomas. A total of 43 cases were classified into T-, B-, and NK/T-cell tumors based on the phenotype expressions of CD3(+)/CD20(-)/CD56(-), CD3(-)/CD20(+)/CD56(-), and CD3(+)/CD20(-)/CD56(+), respectively. The presence of EBV in the tumor was confirmed by EBV early RNA-in situ hybridization. LMP-1 gene deletion and TCR gamma gene rearrangement were analyzed by polymerase chain reaction on paraffin-embedded tissues. There were 20 NK/T-, eight T-, and 15 B-cell phenotype lymphomas in the present series, and EBV was detected in 19 (95%), two (25%), and three (20%) cases in the respective groups. All EBV+ cases carried 30-bp deletion in the LMP-1 gene, and two of the NK/T-cell cases were infected by both the wild type and deleted strains. Five (25%) of the NK/T-cell phenotype lymphomas showed rearranged TCR gamma gene. The present study revealed a high frequency of EBV association, and a high frequency of 30-bp deletion in the LMP-1 gene in the virus in the present series of lymphoma. The NK/T-phenotype lymphomas are comprised of both NK-cell and cytotoxic T-lymphocyte-derived tumors.

Gene Expression of Lytic Endopeptidases AlpA and AlpB from Lysobacter sp. XL1 in Pseudomonads.

PubMed

Tsfasman, Irina M; Lapteva, Yulia S; Krasovskaya, Ludmila A; Kudryakova, Irina V; Vasilyeva, Natalia V; Granovsky, Igor E; Stepnaya, Olga A

2015-01-01

Development of an efficient expression system for (especially secreted) bacterial lytic enzymes is a complicated task due to the specificity of their action. The substrate for such enzymes is peptidoglycan, the main structural component of bacterial cell walls. For this reason, expression of recombinant lytic proteins is often accompanied with lysis of the producing bacterium. This paper presents data on the construction of an inducible system for expression of the lytic peptidases AlpA and AlpB from Lysobacter sp. XL1 in Pseudomonas fluorescens Q2-87, which provides for the successful secretion of these proteins into the culture liquid. In this system, the endopeptidase gene under control of the T7lac promoter was integrated into the bacterial chromosome, as well as the Escherichia coli lactose operon repressor protein gene. The T7 pol gene under lac promoter control, which encodes the phage T7 RNA polymerase, is maintained in Pseudomonas cells on the plasmids. Media and cultivation conditions for the recombinant strains were selected to enable the production of AlpA and AlpB by a simple purification protocol. Production of recombinant lytic enzymes should contribute to the development of new-generation antimicrobial drugs whose application will not be accompanied by selection of resistant microorganisms. © 2015 S. Karger AG, Basel.

Methylation of Epstein-Barr virus Rta promoter in EBV primary infection, reactivation and lymphoproliferation.

PubMed

Germi, Raphaële; Guigue, Nicolas; Lupo, Julien; Semenova, Touyana; Grossi, Laurence; Vermeulen, Odile; Epaulard, Olivier; de Fraipont, Florence; Morand, Patrice

2016-10-01

During Epstein-Barr virus (EBV) latency, the EBV genome is largely silenced by methylation. This silencing is overturned during the switch to the lytic cycle. A key event is the production of the viral protein Zta which binds to three Zta-response elements (ZRE) from the Rta promoter (Rp), two of which (ZRE2 and ZRE3) include three CpG motifs methylated in the latent genome. The bisulphite pyrosequencing reaction was used to quantify the methylation of ZRE2, ZRE3a, and ZRE3b in EBV-positive cell lines and in ex vivo samples of EBV-related diseases, in order to assess whether the level of methylation in these ZREs could provide additional information to viral DNA load and serology in the characterization of EBV-associated diseases. In PBMC from two patients with infectious mononucleosis, over time Rp became increasingly methylated whereas EBV load decreased. In tonsil from patients with chronic tonsillitis, the methylation was less than in EBV-associated tumors, regardless of the viral load. This was even more striking when only the ZRE3a and ZRE3b were considered since some samples presented unbalanced profiles on ZRE2. EBV reactivation in cell culture showed that the reduction in the overall level of methylation was closely related to the production of unmethylated virions. Thus, an assessment of the level of methylation may help to better characterize EBV replication in PBMC and in biopsies with high EBV load, during infectious mononucleosis and EBV-associated cancers. J. Med. Virol. 88:1814-1820, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Sequence analysis of Epstein-Barr virus (EBV) early genes BARF1 and BHRF1 in NK/T cell lymphoma from Northern China.

PubMed

Sun, Lingling; Che, Kui; Zhao, Zhenzhen; Liu, Song; Xing, Xiaoming; Luo, Bing

2015-09-04

NK/T cell lymphoma is an aggressive lymphoma almost always associated with EBV. BamHI-A rightward open reading frame 1 (BARF1) and BamHI-H rightward open reading frame 1 (BHRF1) are two EBV early genes, which may be involved in the oncogenicity of EBV. It has been found that V29A strains, a BARF1 mutant subtype, showed higher prevalence in NPC, which may suggest the association between this variation and nasopharyngeal carcinoma (NPC). To characterize the sequence variation patterns of the Epstein-Barr virus (EBV) early genes and to elucidate their association with NK/T cell lymphoma, we analyzed the sequences of BARF1 and BHRF1 in EBV-positive NK/T cell lymphoma samples from Northern China. In situ hybridization (ISH) performed for EBV-encoded small RNA1 (EBER1) with specific digoxigenin-labeled probes was used to select the EBV positive lymphoma samples. Nested-polymerase chain reaction (nested-PCR) and DNA sequence analysis technique were used to obtain the sequences of BARF1 and BHRF1. The polymorphisms of these two genes were classified according to the signature changes and compared with the known corresponding EBV gene variation data. Two major subtypes of BARF1 gene, designated as B95-8 and V29A subtype, were identified. B95-8 subtype was the dominant subtype. The V29A subtype had one consistent amino acid change at amino acid residue 29 (V → A). Compared with B95-8, AA change at 88 (L → V) of BHRF1 was found in the majority of the isolates, and AA79 (V → L) mutation in a few isolates. Functional domains of BARF1 and BHRF1 were highly conserved. The distributions of BARF1 and BHRF1 subtypes had no significant differences among different EBV-associated malignancies and healthy donors. The sequences of BARF1 and BHRF1 are highly conserved which may contribute to maintain the biological function of these two genes. There is no evidence that particular EBV substrains of BARF1 or BHRF1 is region-restricted or disease-specific.

Gene expression analysis of hypersensitivity to mosquito bite, chronic active EBV infection and NK/T-lymphoma/leukemia.

PubMed

Washio, Kana; Oka, Takashi; Abdalkader, Lamia; Muraoka, Michiko; Shimada, Akira; Oda, Megumi; Sato, Hiaki; Takata, Katsuyoshi; Kagami, Yoshitoyo; Shimizu, Norio; Kato, Seiichi; Kimura, Hiroshi; Nishizaki, Kazunori; Yoshino, Tadashi; Tsukahara, Hirokazu

2017-11-01

The human herpes virus, Epstein-Barr virus (EBV), is a known oncogenic virus and plays important roles in life-threatening T/NK-cell lymphoproliferative disorders (T/NK-cell LPD) such as hypersensitivity to mosquito bite (HMB), chronic active EBV infection (CAEBV), and NK/T-cell lymphoma/leukemia. During the clinical courses of HMB and CAEBV, patients frequently develop malignant lymphomas and the diseases passively progress sequentially. In the present study, gene expression of CD16 (-) CD56 (+) -, EBV (+) HMB, CAEBV, NK-lymphoma, and NK-leukemia cell lines, which were established from patients, was analyzed using oligonucleotide microarrays and compared to that of CD56 bright CD16 dim/- NK cells from healthy donors. Principal components analysis showed that CAEBV and NK-lymphoma cells were relatively closely located, indicating that they had similar expression profiles. Unsupervised hierarchal clustering analyses of microarray data and gene ontology analysis revealed specific gene clusters and identified several candidate genes responsible for disease that can be used to discriminate each category of NK-LPD and NK-cell lymphoma/leukemia.

In vivo intratumoral Epstein-Barr virus replication is associated with XBP1 activation and early-onset post-transplant lymphoproliferative disorders with prognostic implications.

PubMed

Gonzalez-Farre, Blanca; Rovira, Jordina; Martinez, Daniel; Valera, Alexandra; Garcia-Herrera, Adriana; Marcos, Maria Angeles; Sole, Carla; Roue, Gael; Colomer, Dolors; Gonzalvo, Elena; Ribera-Cortada, Imma; Araya, Monica; Lloreta, Josep; Colomo, Luis; Campo, Elias; Lopez-Guillermo, Armando; Martinez, Antonio

2014-12-01

Post-transplant lymphoproliferative disorders are life-threatening complications following hematopoietic or solid organ transplantation. They represent a spectrum of mostly EBV-driven lymphoplasmacytic proliferations. While the oncogenic effect of EBV is related to latent infection, lytic infection also has a role in lymphomagenesis. In vitro, EBV replication is linked to plasma cell differentiation and XBP1 activation, although this phenomenon has never been addressed in vivo. We analyzed for the first time latent and lytic intratumoral EBV infection in a series of 35 adult patients with a diagnosis of post-transplant lymphoproliferative disorder (26M/9F, median age 54 years). A complete EBV study was performed including the analysis of the latent EBER, latent membrane protein-11, and EBV nuclear antigens as well as the immediate-early BZLF1/ZEBRA and early BMRF1/EADE31 lytic genes. XBP1 activation was assessed by nuclear protein expression. EBV infection was observed in 28 (80%) cases being latency II and III the most frequently observed 22 (79%). Intratumoral EBV replication was detected in 17 (60%) cases. Among these, XBP1 activation was observed in 11/12 evaluable cases associated with strong cytoplasmic immunoglobulin expression consistent with plasma cell differentiation. Intriguingly, the combination of latency III infection and EBV replication identified a high-risk subgroup of patients with significantly shorter survival (overall survival at 1 year 18% vs 48%) and early-onset (median of 7 vs 26 months) post-transplant lymphoproliferative disorder. Moreover, these patients appear to be more heavily immunosuppressed, so they exhibit lower rates of rejection and graft vs host disease but higher rates of cytomegalovirus reactivation. In conclusion, EBV replication is associated with plasma cell differentiation and XBP1 activation with prognostic implications. Both latency III and lytic EBV infection are related to aggressive and early-onset post

Epstein-Barr virus (EBV) provides survival factors to EBV+ diffuse large B-cell lymphoma (DLBCL) lines and modulates cytokine induced specific chemotaxis in EBV+  DLBCL.

PubMed

Wu, Liang; Ehlin-Henriksson, Barbro; Zhou, Xiaoying; Zhu, Hong; Ernberg, Ingemar; Kis, Lorand L; Klein, George

2017-12-01

Diffuse large B-cell lymphoma (DLBCL), the most common type of malignant lymphoma, accounts for 30% of adult non-Hodgkin lymphomas. Epstein-Barr virus (EBV) -positive DLBCL of the elderly is a newly recognized subtype that accounts for 8-10% of DLBCLs in Asian countries, but is less common in Western populations. Five DLBCL-derived cell lines were employed to characterize patterns of EBV latent gene expression, as well as response to cytokines and chemotaxis. Interleukin-4 and interleukin-21 modified LMP1, EBNA1 and EBNA2 expression depending on cell phenotype and type of EBV latent programme (type I, II or III). These cytokines also affected CXCR4- or CCR7-mediated chemotaxis in two of the cell lines, Farage (type III) and Val (type II). Further, we investigated the effect of EBV by using dominant-negative EBV nuclear antigen 1(dnEBNA1) to eliminate EBV genomes. This resulted in decreased chemotaxis. By employing an alternative way to eliminate EBV genomes, Roscovitine, we show an increase of apoptosis in the EBV-positive lines. These results show that EBV plays an important role in EBV-positive DLBCL lines with regard to survival and chemotactic response. Our findings provide evidence for the impact of microenvironment on EBV-carrying DLBCL cells and might have therapeutic implications. © 2017 John Wiley & Sons Ltd.

Genomic analysis of Bacillus subtilis lytic bacteriophage ϕNIT1 capable of obstructing natto fermentation carrying genes for the capsule-lytic soluble enzymes poly-γ-glutamate hydrolase and levanase.

PubMed

Ozaki, Tatsuro; Abe, Naoki; Kimura, Keitarou; Suzuki, Atsuto; Kaneko, Jun

2017-01-01

Bacillus subtilis strains including the fermented soybean (natto) starter produce capsular polymers consisting of poly-γ-glutamate and levan. Capsular polymers may protect the cells from phage infection. However, bacteriophage ϕNIT1 carries a γ-PGA hydrolase gene (pghP) that help it to counteract the host cell's protection strategy. ϕNIT had a linear double stranded DNA genome of 155,631-bp with a terminal redundancy of 5,103-bp, containing a gene encoding an active levan hydrolase. These capsule-lytic enzyme genes were located in the possible foreign gene cluster regions between central core and terminal redundant regions, and were expressed at the late phase of the phage lytic cycle. All tested natto origin Spounavirinae phages carried both genes for capsule degrading enzymes similar to ϕNIT1. A comparative genomic analysis revealed the diversity among ϕNIT1 and Bacillus phages carrying pghP-like and levan-hydrolase genes, and provides novel understanding on the acquisition mechanism of these enzymatic genes.

Regulation and dysregulation of Epstein-Barr virus latency: implications for the development of autoimmune diseases.

PubMed

Niller, Hans Helmut; Wolf, Hans; Minarovits, Janos

2008-05-01

Epstein-Barr virus (EBV) is a human herpesvirus hiding in a latent form in memory B cells in the majority of the world population. Although, primary EBV infection is asymptomatic or causes a self-limiting disease, infectious mononucleosis, the virus is associated with a wide variety of neoplasms developing in immunosuppressed or immunodeficient individuals, but also in patients with an apparently intact immune system. In memory B cells, tumor cells, and lymphoblastoid cell lines (LCLs, transformed by EBV in vitro) the expression of the viral genes is highly restricted. There is no virus production (lytic viral replication associated with the expression of all viral genes) in tight latency. The expression of latent viral oncogenes and RNAs is under a strict epigenetic control via DNA methylation and histone modifications that results either in a complete silencing of the EBV genome in memory B cells, or in a cell-type dependent usage of latent promoters in tumor cells, germinal center B cells, and LCLs. Both the latent and lytic EBV proteins are potent immunogens and elicit vigorous B- and T-cell responses. In immunosuppressed and immunodeficient patients, or in individuals with a functional defect of EBV-specific T cells, lytic EBV replication is regularly activated and an increased viral load can be detected in the blood. Enhanced lytic replication results in new infection events and EBV-associated transformation events, and seems to be a risk factor both for malignant transformation and the development of autoimmune diseases. One may speculate that an increased load or altered presentation of a limited set of lytic or latent EBV proteins that cross-react with cellular antigens triggers and perpetuates the pathogenic processes that result in multiple sclerosis, systemic lupus erythematosus (SLE), and rheumatoid arthritis. In addition, in SLE patients EBV may cause defects of B-cell tolerance checkpoints because latent membrane protein 1, an EBV-encoded viral

Differential kinetics and specificity of EBV-specific CD4+ and CD8+ T cells during primary infection.

PubMed

Precopio, Melissa L; Sullivan, John L; Willard, Courtney; Somasundaran, Mohan; Luzuriaga, Katherine

2003-03-01

The generation and maintenance of virus-specific CD4(+) T cells in humans are not well understood. We used short in vitro stimulation assays followed by intracellular cytokine staining to characterize the timing, magnitude, and Ag specificity of CD4(+) T cells over the course of primary EBV infection. Lytic and latent protein-specific CD4(+) T cells were readily detected at presentation with acute infectious mononucleosis and declined rapidly thereafter. Responses to BZLF-1, BMLF-1, and Epstein-Barr nuclear Ag-3A were more commonly detected than responses to Epstein-Barr nuclear Ag-1. Concurrent analyses of BZLF-1-specific CD4(+) and CD8(+) T cells revealed differences in the expansion, specificity, and stability of CD4(+) and CD8(+) T cell-mediated responses over time. Peripheral blood EBV load directly correlated with the frequency of EBV-specific CD4(+) T cell responses at presentation and over time, suggesting that EBV-specific CD4(+) T cell responses are Ag-driven.

Quantitative multi-target RNA profiling in Epstein-Barr virus infected tumor cells.

PubMed

Greijer, A E; Ramayanti, O; Verkuijlen, S A W M; Novalić, Z; Juwana, H; Middeldorp, J M

2017-03-01

Epstein-Barr virus (EBV) is etiologically linked to multiple acute, chronic and malignant diseases. Detection of EBV-RNA transcripts in tissues or biofluids besides EBV-DNA can help in diagnosing EBV related syndromes. Sensitive EBV transcription profiling yields new insights on its pathogenic role and may be useful for monitoring virus targeted therapy. Here we describe a multi-gene quantitative RT-PCR profiling method that simultaneously detects a broad spectrum (n=16) of crucial latent and lytic EBV transcripts. These transcripts include (but are not restricted to), EBNA1, EBNA2, LMP1, LMP2, BARTs, EBER1, BARF1 and ZEBRA, Rta, BGLF4 (PK), BXLF1 (TK) and BFRF3 (VCAp18) all of which have been implicated in EBV-driven oncogenesis and viral replication. With this method we determine the amount of RNA copies per infected (tumor) cell in bulk populations of various origin. While we confirm the expected RNA profiles within classic EBV latency programs, this sensitive quantitative approach revealed the presence of rare cells undergoing lytic replication. Inducing lytic replication in EBV tumor cells supports apoptosis and is considered as therapeutic approach to treat EBV-driven malignancies. This sensitive multi-primed quantitative RT-PCR approach can provide broader understanding of transcriptional activity in latent and lytic EBV infection and is suitable for monitoring virus-specific therapy responses in patients with EBV associated cancers. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

EBV-Positive T/NK-Cell Lymphoproliferative Disease of Childhood

PubMed Central

Hong, Mineui; Yoo, Keon Hee; Koo, Hong Hoe; Kim, Seok Jin; Kim, Won Seog

2013-01-01

Background Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH), EBV-positive systemic T-cell lymphoproliferative disease (STLPD) of childhood, and chronic active EBV (CAEBV) infection may develop after primary EBV infection. This study reviewed the clinicopathological spectrum of EBV-associated T- and natural killer (NK)-cell LPD, including STLPD and CAEBV infection, with an analysis of T-cell clonality. Methods Clinicopathological features of seven patients with EBV-associated HLH or STLPD and 12 patients with CAEBV infection were reviewed. Immunohistochemical staining and a T-cell receptor (TCR) gene rearrangement study were performed. Results STLPD and EBV-positive HLH showed significantly overlapping clinicopathological findings. One patient with STLPD and one patient with EBV-positive HLH demonstrated moderate to severe atypia of the infiltrating lymphocytes, whereas the remaining patients lacked significant atypia. Twelve patients had CAEBV infection, four of whom suffered mosquito-bite hypersensitivity, five showed NK lymphocytosis, and one suffered hydroa vacciniforme. Infiltrating lymphocytes were predominantly small and devoid of atypia. Hemophagocytic histiocytosis was found in seven of 11 patients. Monoclonality was detected in three (50%) of the six patients with successful TCR gene analysis. Conclusions EBV-positive HLH and STLPD share similar clinicopathological findings and may constitute a continuous spectrum of acute EBV-associated T- or NK-cell proliferative disorders. The distinction of EBV-positive T-cell LPD from EBV-positive HLH may be difficult during routine diagnoses because of the technical limitations of clonality assessment. PMID:23667373

EBV-Positive T/NK-Cell Lymphoproliferative Disease of Childhood.

PubMed

Hong, Mineui; Ko, Young Hyeh; Yoo, Keon Hee; Koo, Hong Hoe; Kim, Seok Jin; Kim, Won Seog; Park, Heejung

2013-04-01

Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH), EBV-positive systemic T-cell lymphoproliferative disease (STLPD) of childhood, and chronic active EBV (CAEBV) infection may develop after primary EBV infection. This study reviewed the clinicopathological spectrum of EBV-associated T- and natural killer (NK)-cell LPD, including STLPD and CAEBV infection, with an analysis of T-cell clonality. Clinicopathological features of seven patients with EBV-associated HLH or STLPD and 12 patients with CAEBV infection were reviewed. Immunohistochemical staining and a T-cell receptor (TCR) gene rearrangement study were performed. STLPD and EBV-positive HLH showed significantly overlapping clinicopathological findings. One patient with STLPD and one patient with EBV-positive HLH demonstrated moderate to severe atypia of the infiltrating lymphocytes, whereas the remaining patients lacked significant atypia. Twelve patients had CAEBV infection, four of whom suffered mosquito-bite hypersensitivity, five showed NK lymphocytosis, and one suffered hydroa vacciniforme. Infiltrating lymphocytes were predominantly small and devoid of atypia. Hemophagocytic histiocytosis was found in seven of 11 patients. Monoclonality was detected in three (50%) of the six patients with successful TCR gene analysis. EBV-positive HLH and STLPD share similar clinicopathological findings and may constitute a continuous spectrum of acute EBV-associated T- or NK-cell proliferative disorders. The distinction of EBV-positive T-cell LPD from EBV-positive HLH may be difficult during routine diagnoses because of the technical limitations of clonality assessment.

The lytic origin of herpesvirus papio is highly homologous to Epstein-Barr virus ori-Lyt: evolutionary conservation of transcriptional activation and replication signals.

PubMed Central

Ryon, J J; Fixman, E D; Houchens, C; Zong, J; Lieberman, P M; Chang, Y N; Hayward, G S; Hayward, S D

1993-01-01

Herpesvirus papio (HVP) is a B-lymphotropic baboon virus with an estimated 40% homology to Epstein-Barr virus (EBV). We have cloned and sequenced ori-Lyt of herpesvirus papio and found a striking degree of nucleotide homology (89%) with ori-Lyt of EBV. Transcriptional elements form an integral part of EBV ori-Lyt. The promoter and enhancer domains of EBV ori-Lyt are conserved in herpesvirus papio. The EBV ori-Lyt promoter contains four binding sites for the EBV lytic cycle transactivator Zta, and the enhancer includes one Zta and two Rta response elements. All five of the Zta response elements and one of the Rta motifs are conserved in HVP ori-Lyt, and the HVP DS-L leftward promoter and the enhancer were activated in transient transfection assays by the EBV Zta and Rta transactivators. The EBV ori-Lyt enhancer contains a palindromic sequence, GGTCAGCTGACC, centered on a PvuII restriction site. This sequence, with a single base change, is also present in the HVP ori-Lyt enhancer. DNase I footprinting demonstrated that the PvuII sequence was bound by a protein present in a Raji nuclear extract. Mobility shift and competition assays using oligonucleotide probes identified this sequence as a binding site for the cellular transcription factor MLTF. Mutagenesis of the binding site indicated that MLTF contributes significantly to the constitutive activity of the ori-Lyt enhancer. The high degree of conservation of cis-acting signal sequences in HVP ori-Lyt was further emphasized by the finding that an HVP ori-Lyt-containing plasmid was replicated in Vero cells by a set of cotransfected EBV replication genes. The central domain of EBV ori-Lyt contains two related AT-rich palindromes, one of which is partially duplicated in the HVP sequence. The AT-rich palindromes are functionally important cis-acting motifs. Deletion of these palindromes severely diminished replication of an ori-Lyt target plasmid. Images PMID:8389916

Heterogeneity of the Epstein-Barr Virus (EBV) Major Internal Repeat Reveals Evolutionary Mechanisms of EBV and a Functional Defect in the Prototype EBV Strain B95-8.

PubMed

Ba Abdullah, Mohammed M; Palermo, Richard D; Palser, Anne L; Grayson, Nicholas E; Kellam, Paul; Correia, Samantha; Szymula, Agnieszka; White, Robert E

2017-12-01

Epstein-Barr virus (EBV) is a ubiquitous pathogen of humans that can cause several types of lymphoma and carcinoma. Like other herpesviruses, EBV has diversified through both coevolution with its host and genetic exchange between virus strains. Sequence analysis of the EBV genome is unusually challenging because of the large number and lengths of repeat regions within the virus. Here we describe the sequence assembly and analysis of the large internal repeat 1 of EBV (IR1; also known as the BamW repeats) for more than 70 strains. The diversity of the latency protein EBV nuclear antigen leader protein (EBNA-LP) resides predominantly within the exons downstream of IR1. The integrity of the putative BWRF1 open reading frame (ORF) is retained in over 80% of strains, and deletions truncating IR1 always spare BWRF1. Conserved regions include the IR1 latency promoter (Wp) and one zone upstream of and two within BWRF1. IR1 is heterogeneous in 70% of strains, and this heterogeneity arises from sequence exchange between strains as well as from spontaneous mutation, with interstrain recombination being more common in tumor-derived viruses. This genetic exchange often incorporates regions of <1 kb, and allelic gene conversion changes the frequency of small regions within the repeat but not close to the flanks. These observations suggest that IR1-and, by extension, EBV-diversifies through both recombination and breakpoint repair, while concerted evolution of IR1 is driven by gene conversion of small regions. Finally, the prototype EBV strain B95-8 contains four nonconsensus variants within a single IR1 repeat unit, including a stop codon in the EBNA-LP gene. Repairing IR1 improves EBNA-LP levels and the quality of transformation by the B95-8 bacterial artificial chromosome (BAC). IMPORTANCE Epstein-Barr virus (EBV) infects the majority of the world population but causes illness in only a small minority of people. Nevertheless, over 1% of cancers worldwide are attributable to

Coupled Transcriptome and Proteome Analysis of Human Lymphotropic Tumor Viruses: Insights on the Detection and Discovery of Viral Genes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dresang, Lindsay R.; Teuton, Jeremy R.; Feng, Huichen

Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) are related human tumor viruses that cause primary effusion lymphomas (PEL) and Burkitt's lymphomas (BL), respectively. Viral genes expressed in naturally-infected cancer cells contribute to disease pathogenesis; knowing which viral genes are expressed is critical in understanding how these viruses cause cancer. To evaluate the expression of viral genes, we used high-resolution separation and mass spectrometry coupled with custom tiling arrays to align the viral proteomes and transcriptomes of three PEL and two BL cell lines under latent and lytic culture conditions. Results The majority of viral genes were efficiently detected atmore » the transcript and/or protein level on manipulating the viral life cycle. Overall the correlation of expressed viral proteins and transcripts was highly complementary in both validating and providing orthogonal data with latent/lytic viral gene expression. Our approach also identified novel viral genes in both KSHV and EBV, and extends viral genome annotation. Several previously uncharacterized genes were validated at both transcript and protein levels. Conclusions This systems biology approach coupling proteome and transcriptome measurements provides a comprehensive view of viral gene expression that could not have been attained using each methodology independently. Detection of viral proteins in combination with viral transcripts is a potentially powerful method for establishing virus-disease relationships.« less

B-cell polyclonal activation and Epstein-Barr viral abortive lytic cycle are two key features in acute infectious mononucleosis.

PubMed

Al Tabaa, Yassine; Tuaillon, Edouard; Jeziorski, Eric; Ouedraogo, David Eric; Bolloré, Karine; Rubbo, Pierre-Alain; Foulongne, Vincent; Rodière, Michel; Vendrell, Jean-Pierre

2011-09-01

Acute infectious mononucleosis (AIM) is generally associated with a large EBV B cell reservoir cells and an intense B-cell polyclonal activation whereas the number of quiescent EBV-infected memory B cells in chronically EBV-infected healthy controls is very low. To evaluate the extent and functionality of ex vivo B-cell polyclonal activation, quantify the EBV DNA integrated in B cells, enumerate the functional EBV DNA reservoir in B cells and circulating B cells spontaneously secreting EBV antigens in AIM. Circulating B cells and B cells differentiating into plamablasts and plasma cells, early (BZLF1)- and late viral antigen (gp350)-secreting-cells (SCs) were enumerated in six AIM patients and seven healthy EBV carriers. In vitro B-cell polyclonal activation induced 8000-24,000 BZLF1- and 1000-3000gp350-SCs/10(6) B cells, respectively. These data suggest that only 11.1-19.5% of cells expressing BZLF1 synthesized gp350 and so completed the EBV-lytic cycle. Furthermore, circulating spontaneous BZLF1- and gp350-SCs that reflect ongoing viral replication were rare (20-120 and 10-30/10(6) B cells, respectively), and their low numbers contrasted with the high levels of circulating plasma cells (1.1-10.2% of CD19(+) B cells). The in vivo terminal-B-cell differentiation into plasma cells could unmask EBV B-cell reservoir to specific cytotoxic T-cell response and combined with a predominant abortive functional-EBV-reservoir, strongly contribute to rapid decay of cellular EBV reservoir in AIM. Copyright © 2011 Elsevier B.V. All rights reserved.

Epstein-Barr Virus BGLF4 Kinase Downregulates NF-κB Transactivation through Phosphorylation of Coactivator UXT

PubMed Central

Chang, Ling-Shih; Wang, Jiin-Tarng; Doong, Shin-Lian; Lee, Chung-Pei; Chang, Chou-Wei; Tsai, Ching-Hwa; Yeh, Sheng-Wen; Hsieh, Ching-Yueh

2012-01-01

Epstein-Barr virus (EBV) BGLF4 is a member of the conserved herpesvirus kinases that regulate multiple cellular and viral substrates and play an important role in the viral lytic cycles. BGLF4 has been found to phosphorylate several cellular and viral transcription factors, modulate their activities, and regulate downstream events. In this study, we identify an NF-κB coactivator, UXT, as a substrate of BGLF4. BGLF4 downregulates not only NF-κB transactivation in reporter assays in response to tumor necrosis factor alpha (TNF-α) and poly(I·C) stimulation, but also NF-κB-regulated cellular gene expression. Furthermore, BGLF4 attenuates NF-κB-mediated repression of the EBV lytic transactivators, Zta and Rta. In EBV-positive NA cells, knockdown of BGLF4 during lytic progression elevates NF-κB activity and downregulates the activity of the EBV oriLyt BHLF1 promoter, which is the first promoter activated upon lytic switch. We show that BGLF4 phosphorylates UXT at the Thr3 residue. This modification interferes with the interaction between UXT and NF-κB. The data also indicate that BGLF4 reduces the interaction between UXT and NF-κB and attenuates NF-κB enhanceosome activity. Upon infection with short hairpin RNA (shRNA) lentivirus to knock down UXT, a spontaneous lytic cycle was observed in NA cells, suggesting UXT is required for maintenance of EBV latency. Overexpression of wild-type, but not phosphorylation-deficient, UXT enhances the expression of lytic proteins both in control and UXT knockdown cells. Taking the data together, transcription involving UXT may also be important for EBV lytic protein expression, whereas BGLF4-mediated phosphorylation of UXT at Thr3 plays a critical role in promoting the lytic cycle. PMID:22933289

IL-10-592 A/C polymorphisms is associated with EBV-HLH in Chinese children.

PubMed

Wang, Yali; Ai, Junhong; Xie, Zhengde; Qin, Qiang; Wu, Lingyan; Liu, Yali; Liu, Chunyan; Shen, Kunling

2016-03-01

The aim of this study is to investigate the relationship between cytokine gene polymorphisms and Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) in children, and to further reveal the possible mechanisms of EBV-HLH. Forty-one patients with EBV-HLH, 70 patients with infectious mononucleosis (IM), and 170 EBV-seropositive healthy children were evaluated. Gene polymorphism typing was performed by a polymerase chain reaction with a sequence-specific primer of a commercially available cytokine genotyping kit. Comparison of cytokine gene polymorphisms between EBV-HLH, IM patients, and healthy controls was analyzed statistically using Chi-square test or Fisher's exact test. The frequencies of IL-10-592 C allele or IL-10-592 CC genotype were significantly higher in patients with EBV-HLH than in IM and healthy children (P < 0.001), but no significant difference was observed between IM and healthy children. IL-10-592 locus gene polymorphism is associated with the development of EBV-HLH in Chinese children.

Profiling of EBV-Encoded microRNAs in EBV-Associated Hemophagocytic Lymphohistiocytosis.

PubMed

Zhou, Chen; Xie, Zhengde; Gao, Liwei; Liu, Chunyan; Ai, Junhong; Zhang, Li; Shen, Kunling

2015-10-01

Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) is a life-threatening complication of EBV infection. MicroRNAs (miRNAs) were small non-coding RNA, and EBV could encode miRNAs that are involved in the progression of infection. However, the profiles of EBV-miRNAs in EBV-HLH were unknown. Here, we aimed to profile the expression of EBV-miRNAs in children with EBV-HLH by analyzing 44 known EBV-miRNAs, encoded within the BamHI fragment H rightward open reading frame 1 (BHRF1) and the BamHI-A region rightward transcript (BART), in plasma and cellular targets by real-time quantitative PCR. The study included 15 children with EBV-HLH, 15 children with infectious mononucleosis (IM), and 15 healthy controls. CD8(+) T cells were found to be the cellular target of EBV infection in EBV-HLH, while CD19(+) B cells were infected with EBV in IM. We also found the greater levels of several miRNAs encoded by BART in EBV-HLH, compared to those in IM and healthy controls, whereas the levels of BHRF1 miRNAs were lower than those in IM. The profile and pattern of EBV-miRNAs in EBV-HLH indicated that EBV could display type II latency in EBV-HLH. Importantly, the level of plasma miR-BART16-1 continued decreasing during the whole chemotherapy, suggesting that plasma miR-BART16-1 could be a potential biomarker for monitoring EBV-HLH progression. The pathogenesis of EBV-HLH might be attributed to the abundance of EBV-miRNAs in EBV-HLH. These findings help elucidate the roles of EBV miRNAs in EBV-HLH, enabling the understanding of the basis of this disease and providing clues for its treatment.

Unveiling Another Missing Piece in EBV-Driven Lymphomagenesis: EBV-Encoded MicroRNAs Expression in EBER-Negative Burkitt Lymphoma Cases.

PubMed

Mundo, Lucia; Ambrosio, Maria R; Picciolini, Matteo; Lo Bello, Giuseppe; Gazaneo, Sara; Del Porro, Leonardo; Lazzi, Stefano; Navari, Mohsen; Onyango, Noel; Granai, Massimo; Bellan, Cristiana; De Falco, Giulia; Gibellini, Davide; Piccaluga, Pier P; Leoncini, Lorenzo

2017-01-01

Epstein-Barr virus (EBV) is a gammaherpesvirus linked to a number of lymphoid and epithelial malignancies, including Burkitt lymphoma (BL) in which its frequency ranges from 30% in sporadic cases to 100% in the endemic ones. The possible contribution of EBV to BL pathogenesis is largely unknown. It has been suggested that EBV may be associated with all of the cases, including those diagnosed as EBV negative by a mechanism of hit-and-run . Early during oncogenesis, viral genes are essential for initiating disease. Progressively, viral genome is lost to escape the immune system and host mutations accumulate in proto-oncogenic cell. The main problem with the hit-and-run hypothesis is the lack of evidence in primary tumors. The routine methods applied to detect the virus [i.e., immunohistochemistry and EBV-encoded RNAs (EBER) in situ hybridization (ISH)] have a low specificity and accuracy. The aim of this study was to identify the most suitable method to detect EBV infection in pathology samples by applying conventional and non-conventional methods (i.e., EBV-microRNAs detection and EBV viral load measurement). We investigated a total of 10 cases and we found that all the samples ( n = 6) diagnosed as EBV negative by immunohistochemistry and EBER-ISH demonstrated the presence of EBV-microRNAs and EBV genome. This points at the possibility that EBV might have contributed to lymphomagenesis in all our patients, and propose microRNAs detection as the most specific and sensitive tool to recognize EBV vestiges. It is worth noting that our data would have considerable implications for EBV-related diseases control. By using anti-EBV vaccines, one could potentially prevent also some cancers less suspected of a viral origin because of viral genome loss.

Unveiling Another Missing Piece in EBV-Driven Lymphomagenesis: EBV-Encoded MicroRNAs Expression in EBER-Negative Burkitt Lymphoma Cases

PubMed Central

Mundo, Lucia; Ambrosio, Maria R.; Picciolini, Matteo; Lo Bello, Giuseppe; Gazaneo, Sara; Del Porro, Leonardo; Lazzi, Stefano; Navari, Mohsen; Onyango, Noel; Granai, Massimo; Bellan, Cristiana; De Falco, Giulia; Gibellini, Davide; Piccaluga, Pier P.; Leoncini, Lorenzo

2017-01-01

Epstein–Barr virus (EBV) is a gammaherpesvirus linked to a number of lymphoid and epithelial malignancies, including Burkitt lymphoma (BL) in which its frequency ranges from 30% in sporadic cases to 100% in the endemic ones. The possible contribution of EBV to BL pathogenesis is largely unknown. It has been suggested that EBV may be associated with all of the cases, including those diagnosed as EBV negative by a mechanism of hit-and-run. Early during oncogenesis, viral genes are essential for initiating disease. Progressively, viral genome is lost to escape the immune system and host mutations accumulate in proto-oncogenic cell. The main problem with the hit-and-run hypothesis is the lack of evidence in primary tumors. The routine methods applied to detect the virus [i.e., immunohistochemistry and EBV-encoded RNAs (EBER) in situ hybridization (ISH)] have a low specificity and accuracy. The aim of this study was to identify the most suitable method to detect EBV infection in pathology samples by applying conventional and non-conventional methods (i.e., EBV-microRNAs detection and EBV viral load measurement). We investigated a total of 10 cases and we found that all the samples (n = 6) diagnosed as EBV negative by immunohistochemistry and EBER-ISH demonstrated the presence of EBV-microRNAs and EBV genome. This points at the possibility that EBV might have contributed to lymphomagenesis in all our patients, and propose microRNAs detection as the most specific and sensitive tool to recognize EBV vestiges. It is worth noting that our data would have considerable implications for EBV-related diseases control. By using anti-EBV vaccines, one could potentially prevent also some cancers less suspected of a viral origin because of viral genome loss. PMID:28298901

[Determination of plasma EBV DNA in 91 children with EBV-associated diseases].

PubMed

Duan, Hong-Mei; Yao, Yao; Xie, Zheng-De; Yan, Jing; Hu, Ying-Hui; Yao, Yuan; Zhou, Ling; Shen, Kun-Ling

2009-11-01

To determine the plasma level of Epstein Barr virus (EBV) DNA in children with EBV associated diseases, and to investigate the dynamic changes of EBV DNA level after initial infection as well as the relationship between EBV DNA level and the diseases severity. The subjects consisted of 73 children with primary EBV infection (infectious mononucleosis, pneumonia,etc.) and 18 children with severe EBV-associated diseases (chronic active EBV infection, hemophagocytic lymphohistiocytosis, etc.). The plasma EBV DNA level was detected by a real-time PCR assay. The plasma EBV DNA level decreased with the infection time in children with primary EBV infection. Two weeks after infection, plasma EBV DNA was almost undetectable. The positive rate of plasma EBV DNA in children with severe EBV associated diseases increased significantly when compared with that in children with primary EBV infection (89% vs 16%; p<0.05). The level of EBV replication may be reduced with the infection time. Dynamic determination of blood EBV DNA is useful for the evaluation of disease severity in children with EBV infection.

Sumoylation of the Epstein-Barr Virus BZLF1 Protein Inhibits Its Transcriptional Activity and Is Regulated by the Virus-Encoded Protein Kinase▿

PubMed Central

Hagemeier, Stacy R.; Dickerson, Sarah J.; Meng, Qiao; Yu, Xianming; Mertz, Janet E.; Kenney, Shannon C.

2010-01-01

The Epstein-Barr virus (EBV) immediate-early protein BZLF1 (Z) mediates the switch between latent and lytic EBV infection. Z not only activates early lytic viral gene transcription but also plays a direct role in lytic viral genome replication. Although a small fraction of Z is known to be sumoylated, the effects of this posttranslational modification on various different Z functions have not been well defined. In this report, we show that only the lysine at amino acid residue 12 is required for the sumoylation of Z, and that Z can be sumoylated by SUMO isoforms 1, 2, and 3. We also demonstrate that the sumo-defective Z mutants ZK12A and ZK12R have enhanced transcriptional activity. The sumoylated and nonsumoylated forms of Z were found to have a similar cellular location, both being localized primarily within the nuclear matrix. The Z sumo-defective mutants were, however, partially defective for disrupting promyelocytic leukemia (PML) bodies compared to the ability of wild-type Z. In addition, we show that lytic viral genome replication does not require the sumoylation of Z, although a Z mutant altered at both amino acids 12 and 13 is replication defective. Furthermore, we show that the sumoylation of Z is greatly increased (from less than 1 to about 11%) in lytically induced 293 cells infected with an EBV mutant virus deleted for the EBV-encoded protein kinase (EBV-PK) compared to that of 293 cells infected with wild-type EBV, and that the overexpression of EBV-PK leads to the reduced sumoylation of Z in EBV-negative cells. Our results suggest that the sumoylation of Z helps to promote viral latency, and that EBV-PK inhibits Z sumoylation during viral reactivation. PMID:20181712

Human pathogenic Mycoplasma species induced cytokine gene expression in Epstein-Barr virus (EBV)-positive lymphoblastoid cell lines.

PubMed

Schäffner, E; Opitz, O; Pietsch, K; Bauer, G; Ehlers, S; Jacobs, E

1998-04-01

We addressed the question whether the in vitro interaction of two Epstein-Barr virus (EBV)-genome-positive B cell lines (EB-3 and HilB-gamma) with either Mycoplasma pneumoniae or M. hominis, with the mycoplasma species (M. fermentans, M. fermentans subsp. incognitus, M. penetrans, M. genitalium) or with mycoplasma species known to be mere commensals of the respiratory tract (M. orale and M. salivarium) would result in expression of mRNAs for IL-2, IL-2R, IL-4 and IL-6 as determined by reverse transcriptase (RT)-PCR after 4 and 24 h of cocultivation. The pattern of cytokine gene expression observed depended on (i) the origin of the transformed cell line, (ii) the pathogenicity of the Mycoplasma species, and (iii) the length of cocultivation. The EBV-immortalized lymphoblastoid cell line HilB-gamma showed mRNA expression for IL-2, IL-2-receptor, IL-4 and IL-6 peaking 24 h after stimulation with M. pneumoniae and all AIDS-related mycoplasma species tested. The Burkitt lymphoma cell line EB-3 showed a distinct and isolated strong II-2/IL-2 R-mRNA expression within 4 h after contact with the pathogenic and all of the AIDS related mycoplasma species. In neither EBV-containing cell line cytokine was gene expression detectable after stimulation with the commensal mycoplasma species, M. orale and M. salivarium, indicating species differences in the ability of mycoplasmas to interact with and stimulate B-cell lines. Our data suggest that some mcyoplasma species may act as immunomodulatory cofactors by eliciting inappropriate cytokine gene expression in B cells latently infected with EBV. Therefore, this cultivation model may prove useful in evaluating the pathogenetic potential of novel isolated mycoplasma species. Copyright 1998 Academic Press Limited.

The effect of EBV on WIF1, NLK, and APC gene methylation and expression in gastric carcinoma and nasopharyngeal cancer.

PubMed

Zhao, Zhenzhen; Liu, Wen; Liu, Jincheng; Wang, Jiayi; Luo, Bing

2017-10-01

Epstein-Barr virus (EBV) is an important DNA tumor virus that is associated with approximately 10% of gastric carcinomas and 99% of nasopharyngeal cancers (NPC). DNA methylation and microRNAs (miRNAs) are the most studied epigenetic mechanisms that can prompt disease susceptibility. This study aimed to detect the effect of EBV on Wnt inhibitory factor 1 (WIF1), Nemo-like kinase (NLK), and adenomatous polyposis coli (APC) gene methylation, and expression in gastric carcinoma and NPC. The WIF1, NLK, and APC gene mRNA expression levels were measured by real-time quantitative RT-PCR in four EBV-positive cell lines and four EBV-negative cell lines. Bisulfite genomic sequencing or methylation-specific PCR was used to detect the methylation status of the WIF1, NLK, and APC promoters. All cell lines were treated with 5-azacytidine (5-aza-dC), miR-BART19-3p mimics or an inhibitor, and analyzed by flow cytometry and MTT cell proliferation assays. The WIF1, NLK, and APC promoters were hypermethylated in all eight cell lines. 5-Aza-dC displayed a growth inhibitory effect on cells . After transfection with miR-BART19-3p mimics, the expression of WIF1, and APC decreased, and the cellular proliferation rate increased. After transfection with the miR-BART19-3p inhibitor, the expression levels were higher, and the cell growth was inhibited. In the NPC and GC cell lines, the promoters of WIF1, NLK, and APC are highly methylated, and the expression of these three genes is regulated by miR-BART19-3p. The activity of the Wnt pathway in EBV-associated tumors may be enhanced by miR-BART19-3p. © 2017 Wiley Periodicals, Inc.

Interaction of Epstein-Barr virus (EBV) with human B-lymphocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, George, E-mail: Georg.Klein@ki.se; Klein, Eva; Kashuba, Elena

Epstein-Barr virus, EBV, and humans have a common history that reaches back to our primate ancestors. The virus co-evolved with man and has established a largely harmless and highly complex co-existence. It is carried as silent infection by almost all human adults. A serendipitous discovery established that it is the causative agent of infectious mononucleosis. Still, EBV became known first in 1964, in a rare, geographically prevalent malignant lymphoma of B-cell origin, Burkitt lymphoma BL. Its association with a malignancy prompted intensive studies and its capacity to immortalize B-lymphocytes in vitro was soon demonstrated. Consequently EBV was classified therefore asmore » a potentially tumorigenic virus. Despite of this property however, the virus carrier state itself does not lead to malignancies because the transformed cells are recognized by the immune response. Consequently the EBV induced proliferation of EBV carrying B-lymphocytes is manifested only under immunosuppressive conditions. The expression of EBV encoded genes is regulated by the cell phenotype. The virus genome can be found in malignancies originating from cell types other than the B-lymphocyte. Even in the EBV infected B-cell, the direct transforming capacity is restricted to a defined window of differentiation. A complex interaction between virally encoded proteins and B-cell specific cellular proteins constitute the proliferation inducing program. In this short review we touch upon aspects which are the subject of our present work. We describe the mechanisms of some of the functional interactions between EBV encoded and cellular proteins that determine the phenotype of latently infected B-cells. The growth promoting EBV encoded genes are not expressed in the virus carrying BL cells. Still, EBV seems to contribute to the etiology of this tumor by modifying events that influence cell survival and proliferation. We describe a possible growth promoting mechanism in the genesis of Burkitt

Epstein-Barr virus WZhet DNA can induce lytic replication in epithelial cells in vitro, although WZhet is not detectable in many human tissues in vivo.

PubMed

Ryan, Julie L; Jones, Richard J; Elmore, Sandra H; Kenney, Shannon C; Miller, George; Schroeder, Jane C; Gulley, Margaret L

2009-01-01

WZhet is a rearranged and partially deleted form of the Epstein-Barr virus (EBV) genome in which the BamH1W region becomes juxtaposed with and activates BZLF1, resulting in constitutive viral replication. We tested whether WZhet induces viral replication in epithelial cells, and we studied its prevalence in a wide range of lesional tissues arising in vivo. A quantitative real-time PCR assay targeting EBV WZhet DNA was developed to measure this recombinant form of the EBV genome. WZhet DNA was undetectable in any of 324 plasma or paraffin-embedded tissue samples from patients with EBV-associated and EBV-negative disorders. These included specimens from patients with Hodgkin or non-Hodgkin lymphoma, post-transplant lymphoproliferation, nasopharyngeal or gastric adenocarcinoma, and infectious mononucleosis. However, WZhet DNA was detected in vitro in EBV-infected AGS gastric cancer cells. Additionally, transient transfection of infected AGS gastric cancer cells showed that viral replication could be induced by a WZhet plasmid. This is the first evidence that WZhet induces the EBV lytic cycle in an epithelial cell line. Our negative findings in natural settings suggest that WZhet is a defective viral product that thrives in the absence of a host immune system but is rarely present in vivo. Copyright 2009 S. Karger AG, Basel.

Quercetin-induced apoptosis prevents EBV infection

PubMed Central

Lee, Minjung; Son, Myoungki; Ryu, Eunhyun; Shin, Yu Su; Kim, Jong Gwang; Kang, Byung Woog; Sung, Gi-Ho; Cho, Hyosun; Kang, Hyojeung

2015-01-01

Epstein-Barr virus (EBV) is a human gamma-1 herpesvirus that establishes a lifelong latency in over 90% of the world's population. During latency, virus exists predominantly as a chromatin-associated, multicopy episome in the nuclei of a variety of tumor cells derived from B cells, T cells, natural killer (NK) cells, and epithelial cells. Licorice is the root of Glycyrrhiza uralensis or G. glabra that has traditionally cultivated in eastern part of Asia. Licorice was reported to have anti-viral, anti-inflammatory, anti-atopic, hepatoprotective, anti-neurodegenerative, anti-tumor, anti-diabetic effects and so forth. Quercetin and isoliquiritigenin are produced from licorice and highly similar in molecular structure. They have diverse bioactive effects such as antiviral activity, anti-asthmatic activity, anti-cancer activity, anti-inflammation activity, monoamine-oxidase inhibitor, and etc. To determine anti-EBV and anti-EBVaGC (Epstein-Barr virus associated gastric carcinoma) effects of licorice, we investigated antitumor and antiviral effects of quercetin and isoliquiritigenin against EBVaGC. Although both quercetin and isoliquiritigenin are cytotoxic to SNU719 cells, quercetin induced more apoptosis in SNU719 cells than isoliquiritigenin, more completely eliminated DNMT1 and DNMT3A expressions than isoliquiritigenin, and more strongly affects the cell cycle progression of SNU719 than isoliquiritigenin. Both quercetin and isoliquiritigenin induce signal transductions to stimulate apoptosis, and induce EBV gene transcription. Quercetin enhances frequency of F promoter use, whereas isoliquiritigenin enhances frequency of Q promoter use. Quercetin reduces EBV latency, whereas isoliquiritigenin increases the latency. Quercetin increases more the EBV progeny production, and inhibits more EBV infection than isoliquiritigenin. These results indicate that quercetin could be a promising candidate for antiviral and antitumor agents against EBV and human gastric carcinoma

The Role of Transforming Growth Factor β in Cell-to-Cell Contact-Mediated Epstein-Barr Virus Transmission.

PubMed

Nanbo, Asuka; Ohashi, Makoto; Yoshiyama, Hironori; Ohba, Yusuke

2018-01-01

Infection of Epstein-Barr virus (EBV), a ubiquitous human gamma herpesvirus, is closely linked to various lymphoid and epithelial malignancies. Previous studies demonstrated that the efficiency of EBV infection in epithelial cells is significantly enhanced by coculturing them with latently infected B cells relative to cell-free infection, suggesting that cell-to-cell contact-mediated viral transmission is the dominant mode of infection by EBV in epithelial cells. However, a detailed mechanism underlying this process has not been fully understood. In the present study, we assessed the role of transforming growth factor β (TGF-β), which is known to induce EBV's lytic cycle by upregulation of EBV's latent-lytic switch BZLF1 gene. We have found that 5 days of cocultivation facilitated cell-to-cell contact-mediated EBV transmission. Replication of EBV was induced in cocultured B cells both with and without a direct cell contact in a time-dependent manner. Treatment of a blocking antibody for TGF-β suppressed both induction of the lytic cycle in cocultured B cells and subsequent viral transmission. Cocultivation with epithelial cells facilitated expression of TGF-β receptors in B cells and increased their susceptibility to TGF-β. Finally, we confirmed the spontaneous secretion of TGF-β from epithelial cells, which was not affected by cell-contact. In contrast, the extracellular microvesicles, exosomes derived from cocultured cells partly contributed to cell-to-cell contact-mediated viral transmission. Taken together, our findings support a role for TGF-β derived from epithelial cells in efficient viral transmission, which fosters induction of the viral lytic cycle in the donor B cells.

EBV and Autoimmunity.

PubMed

Ascherio, Alberto; Munger, Kassandra L

2015-01-01

Although a role of EBV in autoimmunity is biologically plausible and evidence of altered immune responses to EBV is abundant in several autoimmune diseases, inference on causality requires the determination that disease risk is higher in individuals infected with EBV than in those uninfected and that in the latter it increases following EBV infection. This determination has so far been possible only for multiple sclerosis (MS) and, to some extent, for systemic lupus erythematosus (SLE), whereas evidence is either lacking or not supportive for other autoimmune conditions. In this chapter, we present the main epidemiological findings that justify the conclusion that EBV is a component cause of MS and SLE and possible mechanisms underlying these effects.

ARID3B: a Novel Regulator of the Kaposi's Sarcoma-Associated Herpesvirus Lytic Cycle

PubMed Central

Wood, Jennifer J.; Boyne, James R.; Paulus, Christina; Jackson, Brian R.; Nevels, Michael M.

2016-01-01

ABSTRACT Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of commonly fatal malignancies of immunocompromised individuals, including primary effusion lymphoma (PEL) and Kaposi's sarcoma (KS). A hallmark of all herpesviruses is their biphasic life cycle—viral latency and the productive lytic cycle—and it is well established that reactivation of the KSHV lytic cycle is associated with KS pathogenesis. Therefore, a thorough appreciation of the mechanisms that govern reactivation is required to better understand disease progression. The viral protein replication and transcription activator (RTA) is the KSHV lytic switch protein due to its ability to drive the expression of various lytic genes, leading to reactivation of the entire lytic cycle. While the mechanisms for activating lytic gene expression have received much attention, how RTA impacts cellular function is less well understood. To address this, we developed a cell line with doxycycline-inducible RTA expression and applied stable isotope labeling of amino acids in cell culture (SILAC)-based quantitative proteomics. Using this methodology, we have identified a novel cellular protein (AT-rich interacting domain containing 3B [ARID3B]) whose expression was enhanced by RTA and that relocalized to replication compartments upon lytic reactivation. We also show that small interfering RNA (siRNA) knockdown or overexpression of ARID3B led to an enhancement or inhibition of lytic reactivation, respectively. Furthermore, DNA affinity and chromatin immunoprecipitation assays demonstrated that ARID3B specifically interacts with A/T-rich elements in the KSHV origin of lytic replication (oriLyt), and this was dependent on lytic cycle reactivation. Therefore, we have identified a novel cellular protein whose expression is enhanced by KSHV RTA with the ability to inhibit KSHV reactivation. IMPORTANCE Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of fatal malignancies of

Lytic and Latent Antigens of the Human Gammaherpesviruses Kaposi's Sarcoma-Associated Herpesvirus and Epstein-Barr Virus Induce T-Cell Responses with Similar Functional Properties and Memory Phenotypes▿

PubMed Central

Bihl, Florian; Narayan, Murli; Chisholm, John V.; Henry, Leah M.; Suscovich, Todd J.; Brown, Elizabeth E.; Welzel, Tania M.; Kaufmann, Daniel E.; Zaman, Tauheed M.; Dollard, Sheila; Martin, Jeff N.; Wang, Fred; Scadden, David T.; Kaye, Kenneth M.; Brander, Christian

2007-01-01

The cellular immunity against Kaposi's sarcoma-associated herpesvirus (KSHV) is poorly characterized and has not been compared to T-cell responses against other human herpesviruses. Here, novel and dominant targets of KSHV-specific cellular immunity are identified and compared to T cells specific for lytic and latent antigens in a second human gammaherpesvirus, Epstein-Barr virus. The data identify a novel HLA-B57- and HLA-B58-restricted epitope in the Orf57 protein and show consistently close parallels in immune phenotypes and functional response patterns between cells targeting lytic or latent KSHV- and EBV-encoded antigens, suggesting common mechanisms in the induction of these responses. PMID:17329344

Lytic and latent antigens of the human gammaherpesviruses Kaposi's sarcoma-associated herpesvirus and Epstein-Barr virus induce T-cell responses with similar functional properties and memory phenotypes.

PubMed

Bihl, Florian; Narayan, Murli; Chisholm, John V; Henry, Leah M; Suscovich, Todd J; Brown, Elizabeth E; Welzel, Tania M; Kaufmann, Daniel E; Zaman, Tauheed M; Dollard, Sheila; Martin, Jeff N; Wang, Fred; Scadden, David T; Kaye, Kenneth M; Brander, Christian

2007-05-01

The cellular immunity against Kaposi's sarcoma-associated herpesvirus (KSHV) is poorly characterized and has not been compared to T-cell responses against other human herpesviruses. Here, novel and dominant targets of KSHV-specific cellular immunity are identified and compared to T cells specific for lytic and latent antigens in a second human gammaherpesvirus, Epstein-Barr virus. The data identify a novel HLA-B57- and HLA-B58-restricted epitope in the Orf57 protein and show consistently close parallels in immune phenotypes and functional response patterns between cells targeting lytic or latent KSHV- and EBV-encoded antigens, suggesting common mechanisms in the induction of these responses.

Efficient Immortalization of Primary Nasopharyngeal Epithelial Cells for EBV Infection Study

PubMed Central

Yip, Yim Ling; Pang, Pei Shin; Deng, Wen; Tsang, Chi Man; Zeng, Musheng; Hau, Pok Man; Man, Cornelia; Jin, Yuesheng; Yuen, Anthony Po Wing; Tsao, Sai Wah

2013-01-01

Nasopharyngeal carcinoma (NPC) is common among southern Chinese including the ethnic Cantonese population living in Hong Kong. Epstein-Barr virus (EBV) infection is detected in all undifferentiated type of NPC in this endemic region. Establishment of stable and latent EBV infection in premalignant nasopharyngeal epithelial cells is an early event in NPC development and may contribute to its pathogenesis. Immortalized primary nasopharyngeal epithelial cells represent an important tool for investigation of EBV infection and its tumorigenic potential in this special type of epithelial cells. However, the limited availability and small sizes of nasopharyngeal biopsies have seriously restricted the establishment of primary nasopharyngeal epithelial cells for immortalization. A reliable and effective method to immortalize primary nasopharyngeal epithelial cells will provide unrestricted materials for EBV infection studies. An earlier study has reported that Bmi-1 expression could immortalize primary nasopharyngeal epithelial cells. However, its efficiency and actions in immortalization have not been fully characterized. Our studies showed that Bmi-1 expression alone has limited ability to immortalize primary nasopharyngeal epithelial cells and additional events are often required for its immortalization action. We have identified some of the key events associated with the immortalization of primary nasopharyngeal epithelial cells. Efficient immortalization of nasopharyngeal epithelial cells could be reproducibly and efficiently achieved by the combined actions of Bmi-1 expression, activation of telomerase and silencing of p16 gene. Activation of MAPK signaling and gene expression downstream of Bmi-1 were detected in the immortalized nasopharyngeal epithelial cells and may play a role in immortalization. Furthermore, these newly immortalized nasopharyngeal epithelial cells are susceptible to EBV infection and supported a type II latent EBV infection program characteristic

Transcriptional activation signals found in the Epstein-Barr virus (EBV) latency C promoter are conserved in the latency C promoter sequences from baboon and Rhesus monkey EBV-like lymphocryptoviruses (cercopithicine herpesviruses 12 and 15).

PubMed

Fuentes-Pananá, E M; Swaminathan, S; Ling, P D

1999-01-01

The Epstein-Barr virus (EBV) EBNA2 protein is a transcriptional activator that controls viral latent gene expression and is essential for EBV-driven B-cell immortalization. EBNA2 is expressed from the viral C promoter (Cp) and regulates its own expression by activating Cp through interaction with the cellular DNA binding protein CBF1. Through regulation of Cp and EBNA2 expression, EBV controls the pattern of latent protein expression and the type of latency established. To gain further insight into the important regulatory elements that modulate Cp usage, we isolated and sequenced the Cp regions corresponding to nucleotides 10251 to 11479 of the EBV genome (-1079 to +144 relative to the transcription initiation site) from the EBV-like lymphocryptoviruses found in baboons (herpesvirus papio; HVP) and Rhesus macaques (RhEBV). Sequence comparison of the approximately 1,230-bp Cp regions from these primate viruses revealed that EBV and HVP Cp sequences are 64% conserved, EBV and RhEBV Cp sequences are 66% conserved, and HVP and RhEBV Cp sequences are 65% conserved relative to each other. Approximately 50% of the residues are conserved among all three sequences, yet all three viruses have retained response elements for glucocorticoids, two positionally conserved CCAAT boxes, and positionally conserved TATA boxes. The putative EBNA2 100-bp enhancers within these promoters contain 54 conserved residues, and the binding sites for CBF1 and CBF2 are well conserved. Cp usage in the HVP- and RhEBV-transformed cell lines was detected by S1 nuclease protection analysis. Transient-transfection analysis showed that promoters of both HVP and RhEBV are responsive to EBNA2 and that they bind CBF1 and CBF2 in gel mobility shift assays. These results suggest that similar mechanisms for regulation of latent gene expression are conserved among the EBV-related lymphocryptoviruses found in nonhuman primates.

Lytic to temperate switching of viral communities

NASA Astrophysics Data System (ADS)

Knowles, B.; Silveira, C. B.; Bailey, B. A.; Barott, K.; Cantu, V. A.; Cobián-Güemes, A. G.; Coutinho, F. H.; Dinsdale, E. A.; Felts, B.; Furby, K. A.; George, E. E.; Green, K. T.; Gregoracci, G. B.; Haas, A. F.; Haggerty, J. M.; Hester, E. R.; Hisakawa, N.; Kelly, L. W.; Lim, Y. W.; Little, M.; Luque, A.; McDole-Somera, T.; McNair, K.; de Oliveira, L. S.; Quistad, S. D.; Robinett, N. L.; Sala, E.; Salamon, P.; Sanchez, S. E.; Sandin, S.; Silva, G. G. Z.; Smith, J.; Sullivan, C.; Thompson, C.; Vermeij, M. J. A.; Youle, M.; Young, C.; Zgliczynski, B.; Brainard, R.; Edwards, R. A.; Nulton, J.; Thompson, F.; Rohwer, F.

2016-03-01

Microbial viruses can control host abundances via density-dependent lytic predator-prey dynamics. Less clear is how temperate viruses, which coexist and replicate with their host, influence microbial communities. Here we show that virus-like particles are relatively less abundant at high host densities. This suggests suppressed lysis where established models predict lytic dynamics are favoured. Meta-analysis of published viral and microbial densities showed that this trend was widespread in diverse ecosystems ranging from soil to freshwater to human lungs. Experimental manipulations showed viral densities more consistent with temperate than lytic life cycles at increasing microbial abundance. An analysis of 24 coral reef viromes showed a relative increase in the abundance of hallmark genes encoded by temperate viruses with increased microbial abundance. Based on these four lines of evidence, we propose the Piggyback-the-Winner model wherein temperate dynamics become increasingly important in ecosystems with high microbial densities; thus ‘more microbes, fewer viruses’.

Identification of the Essential Role of Viral Bcl-2 for Kaposi's Sarcoma-Associated Herpesvirus Lytic Replication

PubMed Central

Liang, Qiming; Chang, Brian; Lee, Patrick; Brulois, Kevin F.; Ge, Jianning; Shi, Mude; Rodgers, Mary A.; Feng, Pinghui; Oh, Byung-Ha; Liang, Chengyu

2015-01-01

ABSTRACT Kaposi's sarcoma-associated herpesvirus (KSHV) evades host defenses through tight suppression of autophagy by targeting each step of its signal transduction: by viral Bcl-2 (vBcl-2) in vesicle nucleation, by viral FLIP (vFLIP) in vesicle elongation, and by K7 in vesicle maturation. By exploring the roles of KSHV autophagy-modulating genes, we found, surprisingly, that vBcl-2 is essential for KSHV lytic replication, whereas vFLIP and K7 are dispensable. Knocking out vBcl-2 from the KSHV genome resulted in decreased lytic gene expression at the mRNA and protein levels, a lower viral DNA copy number, and, consequently, a dramatic reduction in the amount of progeny infectious viruses, as also described in the accompanying article (A. Gelgor, I. Kalt, S. Bergson, K. F. Brulois, J. U. Jung, and R. Sarid, J Virol 89:5298–5307, 2015). More importantly, the antiapoptotic and antiautophagic functions of vBcl-2 were not required for KSHV lytic replication. Using a comprehensive mutagenesis analysis, we identified that glutamic acid 14 (E14) of vBcl-2 is critical for KSHV lytic replication. Mutating E14 to alanine totally blocked KSHV lytic replication but showed little or no effect on the antiapoptotic and antiautophagic functions of vBcl-2. Our study indicates that vBcl-2 harbors at least three important and genetically separable functions to modulate both cellular signaling and the virus life cycle. IMPORTANCE The present study shows for the first time that vBcl-2 is essential for KSHV lytic replication. Removal of the vBcl-2 gene results in a lower level of KSHV lytic gene expression, impaired viral DNA replication, and consequently, a dramatic reduction in the level of progeny production. More importantly, the role of vBcl-2 in KSHV lytic replication is genetically separated from its antiapoptotic and antiautophagic functions, suggesting that the KSHV Bcl-2 carries a novel function in viral lytic replication. PMID:25740994

Reactivation and Lytic Replication of Kaposi’s Sarcoma-Associated Herpesvirus: An Update

PubMed Central

Aneja, Kawalpreet K.; Yuan, Yan

2017-01-01

The life cycle of Kaposi’s sarcoma-associated herpesvirus (KSHV) consists of two phases, latent and lytic. The virus establishes latency as a strategy for avoiding host immune surveillance and fusing symbiotically with the host for lifetime persistent infection. However, latency can be disrupted and KSHV is reactivated for entry into the lytic replication. Viral lytic replication is crucial for efficient dissemination from its long-term reservoir to the sites of disease and for the spread of the virus to new hosts. The balance of these two phases in the KSHV life cycle is important for both the virus and the host and control of the switch between these two phases is extremely complex. Various environmental factors such as oxidative stress, hypoxia, and certain chemicals have been shown to switch KSHV from latency to lytic reactivation. Immunosuppression, unbalanced inflammatory cytokines, and other viral co-infections also lead to the reactivation of KSHV. This review article summarizes the current understanding of the initiation and regulation of KSHV reactivation and the mechanisms underlying the process of viral lytic replication. In particular, the central role of an immediate-early gene product RTA in KSHV reactivation has been extensively investigated. These studies revealed multiple layers of regulation in activation of RTA as well as the multifunctional roles of RTA in the lytic replication cascade. Epigenetic regulation is known as a critical layer of control for the switch of KSHV between latency and lytic replication. The viral non-coding RNA, PAN, was demonstrated to play a central role in the epigenetic regulation by serving as a guide RNA that brought chromatin remodeling enzymes to the promoters of RTA and other lytic genes. In addition, a novel dimension of regulation by microPeptides emerged and has been shown to regulate RTA expression at the protein level. Overall, extensive investigation of KSHV reactivation and lytic replication has revealed

[Potential role of the Epstein-Barr virus in the pathogenesis of systemic lupus erythematosus and kidney diseases].

PubMed

Roszkowiak, Bogna; Niemir, Zofia I

2004-01-01

Epstein-Barr virus (EBV) is mainly regarded as a tumorigenic agent widely distributed in the adult population. Recent results also indicate its potential role in systemic autoimmune diseases as well as in renal disorders. This is thought to be due to the virus's capacity to invade B cells and change from the lytic linear form to the circular latent one, which allows restriction in its gene expression array. In this way the virus avoids recognition by CD4+ and CD8+ cells and escapes immunological control. Defective control of lytic and/or latent EBV infection may contribute to the development of systemic or renal pathology.

[Sequential monitoring of plasma EBV-DNA level in a patient with EBV-positive Hodgkin lymphoma].

PubMed

Uchida, Emi; Honma, Riko; Igarashi, Aiko; Kurata, Morito; Imadome, Ken-Ichi; Omoto, Eijiro; Miura, Osamu; Arai, Ayako

2012-01-01

A 58-year-old woman was admitted to our hospital because of fever, systemic lymphadenopathy with abnormal Epstein-Barr virus (EBV) antibody titers, and a high EBV-DNA load in the serum. She had been diagnosed as possibly having chronic active EBV infection (CAEBV) during a previous hospitalization. The EBV-DNA load of the plasma (pEBV-DNA), examined at our hospital, was elevated to 1.8×10(4) copies/ml, whereas that of the peripheral blood mononuclear cells was 3.4×10(1) copies/μg DNA, which was not clearly elevated, unlike in cases with CAEBV. Biopsy of the cervical lymph node was performed and the diagnosis of mixed cellularity classical Hodgkin lymphoma, Stage4B was made. Hodgkin cells were positive for EBV. COPP therapy was started and pEBV-DNA decreased drastically. The treatment was followed by ABVD therapy and pEBV-DNA turned negative after one course of ABVD therapy. She achieved complete response after 4 courses of the treatment. Reports from abroad indicate that pEBV-DNA parallels the disease state of EBV-positive Hodgkin lymphoma. Our results were consistent with these reports, and demonstrated that, in a Japanese patient, EBV-DNA load and its localization in the peripheral blood fractions could be useful tools for diagnosis as well as evaluating the disease status.

[Significance of detecting the EBV-DNA level in peripheral blood mononuclear cells and the EBV-infected cell type in patients with chronic active EBV infection].

PubMed

Xing, Yan; Song, Hong-mei; Wu, Xiao-yan; Wang, Wei; Wei, Min

2011-07-01

To study the difference in the EBV-DNA level in peripheral blood mononuclear cells (PBMC) and the type of Epstein-Barr virus (EBV)-infected cells in pediatric patients with chronic active EBV (CAEBV) infection, acute EBV infection (AEBV) and healthy children, and to analyze the relationship between the above difference and the clinical manifestation of CAEBV. Real-time fluorescent quantitative polymerase chain reaction (PCR) was used to detect the EBV-DNA levels in peripheral blood mononuclear cells (PBMC) in 12 normal children, 10 pediatric patients with CAEBV infection and 13 pediatric patients with AEBV infection in our hospital between March 2004 and April 2008. Immunomagnetic bead cell fractionation and fluorescent in situ hybridization (FISH) by EBV encoding RNA-1 ( EBER-1) probe were used in the healthy children, EBV-DNA positive CAEBV patients and AEBV patients to detect the type of EBV-infected cells. The average EBV-DNA level in CAEBV patients' PBMC was (6.8 x 10(7) +/- 1.1 x 10(8)) copies/ml, while the average EBV-DNA level of AEBV patients' PBMC was (1.3 x 10(6) +/- 1.6 x 10(6)) copies/ml. The average EBV-DNA level of CAEBV infected patients' PBMC was significantly higher than that of AEBV infected patients' PBMC (P<0.01). The cell fractionation and FISH in seven CAEBV patients showed that EBV in CAEBV patients infected not only B cells, but NK cells and CD4+ and CD8+ T cells to different degree, and these patients presented recurrent and persistent infectious mononucleosis (IM)-like symptoms. In 6 CAEBV patients infection mainly occurred to T cells, in one case, infection occurred mainly in CD8+ T cells, and the patient died from fulminant and deadly T lymphocytes proliferative syndrome except presenting firstly high fever, enlargment of the liver, spleen, lymphnode and the severe decrease of one or three kinds of blood cells. In 1 CAEBV patient the infection was mainly found in NK cells, who presented with hypersensitivity to mosquito biting and high

Cutaneous EBV-related lymphoproliferative disorders.

PubMed

Gru, Alejandro A; Jaffe, Elaine S

2017-01-01

This article will focus on the cutaneous lymphoproliferative disorders associated with EBV, with an emphasis on the upcoming changes in the revised 4th Edition of the WHO classification of tumors of the hematopoietic system, many of which deal with cutaneous disorders derived from NK-cells or T-cells. Extranodal NK/T-cell lymphoma usually presents in the upper aerodigestive tract, but can involve the skin secondarily. EBV-associated T- and NK-cell lymphoproliferative disorders (LPD) in the pediatric age group include the systemic diseases, chronic active EBV infection (CAEBV) and systemic EBV+ T-cell lymphoma of childhood. Hydroa vacciniforme (HV)-like LPD is a primarily cutaneous form of CAEBV and encompasses the lesions previously referred to as HV and HV-like lymphoma (HVLL). All the T/NK-cell-EBV-associated diseases occur with higher frequency in Asians, and indigenous populations from Central and South America and Mexico. Among the B-cell EBV-associated LPD two major changes have been introduced in the WHO. The previously designated EBV-positive diffuse large B-cell lymphoma (EBV-DLBCL) of the elderly, has been changed to EBV-DLBCL with 'not otherwise specified' as a modifier (NOS). A new addition to the WHO system is the more recently identified EBV+ mucocutaneous ulcer, which involves skin and mucosal-associated sites. Copyright © 2017 Elsevier Inc. All rights reserved.

Transcriptional Activation Signals Found in the Epstein-Barr Virus (EBV) Latency C Promoter Are Conserved in the Latency C Promoter Sequences from Baboon and Rhesus Monkey EBV-Like Lymphocryptoviruses (Cercopithicine Herpesviruses 12 and 15)

PubMed Central

Fuentes-Pananá, Ezequiel M.; Swaminathan, Sankar; Ling, Paul D.

1999-01-01

The Epstein-Barr virus (EBV) EBNA2 protein is a transcriptional activator that controls viral latent gene expression and is essential for EBV-driven B-cell immortalization. EBNA2 is expressed from the viral C promoter (Cp) and regulates its own expression by activating Cp through interaction with the cellular DNA binding protein CBF1. Through regulation of Cp and EBNA2 expression, EBV controls the pattern of latent protein expression and the type of latency established. To gain further insight into the important regulatory elements that modulate Cp usage, we isolated and sequenced the Cp regions corresponding to nucleotides 10251 to 11479 of the EBV genome (−1079 to +144 relative to the transcription initiation site) from the EBV-like lymphocryptoviruses found in baboons (herpesvirus papio; HVP) and Rhesus macaques (RhEBV). Sequence comparison of the approximately 1,230-bp Cp regions from these primate viruses revealed that EBV and HVP Cp sequences are 64% conserved, EBV and RhEBV Cp sequences are 66% conserved, and HVP and RhEBV Cp sequences are 65% conserved relative to each other. Approximately 50% of the residues are conserved among all three sequences, yet all three viruses have retained response elements for glucocorticoids, two positionally conserved CCAAT boxes, and positionally conserved TATA boxes. The putative EBNA2 100-bp enhancers within these promoters contain 54 conserved residues, and the binding sites for CBF1 and CBF2 are well conserved. Cp usage in the HVP- and RhEBV-transformed cell lines was detected by S1 nuclease protection analysis. Transient-transfection analysis showed that promoters of both HVP and RhEBV are responsive to EBNA2 and that they bind CBF1 and CBF2 in gel mobility shift assays. These results suggest that similar mechanisms for regulation of latent gene expression are conserved among the EBV-related lymphocryptoviruses found in nonhuman primates. PMID:9847397

Genetic factors affecting EBV copy number in lymphoblastoid cell lines derived from the 1000 Genome Project samples.

PubMed

Mandage, Rajendra; Telford, Marco; Rodríguez, Juan Antonio; Farré, Xavier; Layouni, Hafid; Marigorta, Urko M; Cundiff, Caitlin; Heredia-Genestar, Jose Maria; Navarro, Arcadi; Santpere, Gabriel

2017-01-01

Epstein-Barr virus (EBV), human herpes virus 4, has been classically associated with infectious mononucleosis, multiple sclerosis and several types of cancers. Many of these diseases show marked geographical differences in prevalence, which points to underlying genetic and/or environmental factors. Those factors may include a different susceptibility to EBV infection and viral copy number among human populations. Since EBV is commonly used to transform B-cells into lymphoblastoid cell lines (LCLs) we hypothesize that differences in EBV copy number among individual LCLs may reflect differential susceptibility to EBV infection. To test this hypothesis, we retrieved whole-genome sequenced EBV-mapping reads from 1,753 LCL samples derived from 19 populations worldwide that were sequenced within the context of the 1000 Genomes Project. An in silico methodology was developed to estimate the number of EBV copy number in LCLs and validated these estimations by real-time PCR. After experimentally confirming that EBV relative copy number remains stable over cell passages, we performed a genome wide association analysis (GWAS) to try detecting genetic variants of the host that may be associated with EBV copy number. Our GWAS has yielded several genomic regions suggestively associated with the number of EBV genomes per cell in LCLs, unraveling promising candidate genes such as CAND1, a known inhibitor of EBV replication. While this GWAS does not unequivocally establish the degree to which genetic makeup of individuals determine viral levels within their derived LCLs, for which a larger sample size will be needed, it potentially highlighted human genes affecting EBV-related processes, which constitute interesting candidates to follow up in the context of EBV related pathologies.

Radiation-induced Epstein-Barr virus reactivation in gastric cancer cells with latent EBV infection.

PubMed

Nandakumar, Athira; Uwatoko, Futoshi; Yamamoto, Megumi; Tomita, Kazuo; Majima, Hideyuki J; Akiba, Suminori; Koriyama, Chihaya

2017-07-01

Epstein-Barr virus, a ubiquitous human herpes virus with oncogenic activity, can be found in 6%-16% of gastric carcinomas worldwide. In Epstein-Barr virus-associated gastric carcinoma, only a few latent genes of the virus are expressed. Ionizing irradiation was shown to induce lytic Epstein-Barr virus infection in lymphoblastoid cell lines with latent Epstein-Barr virus infection. In this study, we examined the effect of ionizing radiation on the Epstein-Barr virus reactivation in a gastric epithelial cancer cell line (SNU-719, an Epstein-Barr virus-associated gastric carcinoma cell line). Irradiation with X-ray (dose = 5 and 10 Gy; dose rate = 0.5398 Gy/min) killed approximately 25% and 50% of cultured SNU-719 cells, respectively, in 48 h. Ionizing radiation increased the messenger RNA expression of immediate early Epstein-Barr virus lytic genes (BZLF1 and BRLF1), determined by real-time reverse transcription polymerase chain reaction, in a dose-dependent manner at 48 h and, to a slightly lesser extent, at 72 h after irradiation. Similar findings were observed for other Epstein-Barr virus lytic genes (BMRF1, BLLF1, and BcLF1). After radiation, the expression of transforming growth factor beta 1 messenger RNA increased and reached a peak in 12-24 h, and the high-level expression of the Epstein-Barr virus immediate early genes can convert latent Epstein-Barr virus infection into the lytic form and result in the release of infectious Epstein-Barr virus. To conclude, Ionizing radiation activates lytic Epstein-Barr virus gene expression in the SNU-719 cell line mainly through nuclear factor kappaB activation. We made a brief review of literature to explore underlying mechanism involved in transforming growth factor beta-induced Epstein-Barr virus reactivation. A possible involvement of nuclear factor kappaB was hypothesized.

An Epstein-Barr virus-associated superantigen

PubMed Central

1996-01-01

More than 90% of adults are latently infected with Epstein-Barr virus (EBV), the causative agent of infectious mononucleosis, a self-limiting lymphoproliferative disease characterized by extensive T cell activation. Reactivation of this herpesvirus during immunosuppression is often associated with oncogenesis. These considerations led us to analyze the early events that occur after exposure of the immune system to EBV. Strong major histocompatibility complex (MHC) class II- dependent but not MHC-restricted, T cell proliferation was observed in vitro in response to autologous, lytically infected EBV-transformed B cells. By measuring the appearance of the early activation marker CD69 on individual T cell V beta subsets, we could demonstrate selective activation of human V beta 13- T cells. This was confirmed with murine T cell hybridomas expressing various human BV genes. While EBV- Burkitt's lymphoma cells were nonstimulatory, they induced V beta- restricted T cell activation after EBV infection. EBV specific activation was also demonstrated in cord blood cells, excluding a recall-antigen response. Thus, all of the characteristics of a superantigen-stimulated response are seen, indicating that induction of the EBV lytic cycle is associated with the expression of a superantigen in B cells. A model is presented proposing a role for the superantigen in infection, latency, and oncogenesis. PMID:9064357

Evaluation of the presence of Epstein-Barr virus (EBV) in Iranian patients with thyroid papillary carcinoma.

PubMed

Homayouni, Maryam; Mohammad Arabzadeh, Seyed Ali; Nili, Fatemeh; Razi, Farideh; Amoli, Mahsa Mohammad

2017-07-01

Papillary thyroid carcinoma (PTC) is the most common thyroid cancer. EBV is one of the most important viruses related to different types of malignancies. This study investigated the relationship between EBV and papillary thyroid carcinoma. In this study the presence of Epstein-Barr Nuclear Antigen 1 (EBNA1) gene in papillary thyroid carcinoma tissues were examined by nested-PCR method. Paraffin-embedded tissues (N=41) blocks of thyroid cancer were used. DNA was extracted from all samples and then samples were evaluated for the presence of EBV gene. In 41 samples, EBNA1 was detected in 65.8% of patients with papillary thyroid carcinoma which was significantly higher in younger ages. The significant presence of EBV genome in papillary thyroid carcinoma suggests that this virus may play a role in this cancer especially in younger ages. As a result, monitoring of patients with EBV latent infection for PTC can be very important. Copyright © 2017 Elsevier GmbH. All rights reserved.

Kinetics of Epstein-Barr Virus (EBV) Neutralizing and Virus-Specific Antibodies after Primary Infection with EBV

PubMed Central

Bu, Wei; Hayes, Gregory M.; Liu, Hui; Gemmell, Lorraine; Schmeling, David O.; Radecki, Pierce; Aguilar, Fiona; Burbelo, Peter D.; Woo, Jennifer; Balfour, Henry H.

2016-01-01

Prospective studies of antibodies to multiple Epstein-Barr virus (EBV) proteins and EBV neutralizing antibodies in the same individuals before, during, and after primary EBV infection have not been reported. We studied antibody responses to EBV in college students who acquired primary EBV infection during prospective surveillance and correlated the kinetics of antibody response with the severity of disease. Neutralizing antibodies and enzyme-linked immunosorbent assay (ELISA) antibodies to gp350, the major target of neutralizing antibody, reached peak levels at medians of 179 and 333 days after the onset of symptoms of infectious mononucleosis, respectively. No clear correlation was found between the severity of the symptoms of infectious mononucleosis and the peak levels of antibody to individual viral proteins or to neutralizing antibody. In summary, we found that titers of neutralizing antibody and antibodies to multiple EBV proteins increase over many months after primary infection with EBV. PMID:26888186

Epstein-Barr Virus (EBV) DNA in plasma is not encapsidated in patients with EBV-related malignancies.

PubMed

Ryan, Julie L; Fan, Hongxin; Swinnen, Lode J; Schichman, Steven A; Raab-Traub, Nancy; Covington, Mary; Elmore, Sandra; Gulley, Margaret L

2004-06-01

Epstein-Barr Virus (EBV), a ubiquitous gamma herpes virus, infects more than 95% of the human population before adulthood. Life-long persistence, usually without adverse health consequences, relies on a balance between viral latency, viral replication, and host immune response. Patients with EBV-related disease often have high levels of EBV DNA in their plasma. This study addresses whether this circulating, cell-free EBV DNA is encapsidated in virions or exists as naked genomes. First, an assay was developed, combining DNase I and quantitative real-time PCR, to discriminate encapsidated from naked EBV DNA. EBV DNA was almost always naked in the plasma of AIDS-related lymphoma patients (n = 11) and immunosuppressed/posttransplantation patients (n = 8). In contrast, infectious mononucleosis patients (n = 30) often had a mixture of encapsidated and naked EBV DNA. These findings may be important in understanding how viral load relates to disease status and in predicting response to nucleoside analogs and other antiviral therapies.

Kinetics of Epstein-Barr Virus (EBV) Neutralizing and Virus-Specific Antibodies after Primary Infection with EBV.

PubMed

Bu, Wei; Hayes, Gregory M; Liu, Hui; Gemmell, Lorraine; Schmeling, David O; Radecki, Pierce; Aguilar, Fiona; Burbelo, Peter D; Woo, Jennifer; Balfour, Henry H; Cohen, Jeffrey I

2016-04-01

Prospective studies of antibodies to multiple Epstein-Barr virus (EBV) proteins and EBV neutralizing antibodies in the same individuals before, during, and after primary EBV infection have not been reported. We studied antibody responses to EBV in college students who acquired primary EBV infection during prospective surveillance and correlated the kinetics of antibody response with the severity of disease. Neutralizing antibodies and enzyme-linked immunosorbent assay (ELISA) antibodies to gp350, the major target of neutralizing antibody, reached peak levels at medians of 179 and 333 days after the onset of symptoms of infectious mononucleosis, respectively. No clear correlation was found between the severity of the symptoms of infectious mononucleosis and the peak levels of antibody to individual viral proteins or to neutralizing antibody. In summary, we found that titers of neutralizing antibody and antibodies to multiple EBV proteins increase over many months after primary infection with EBV. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Primary EBV Infection Induces an Expression Profile Distinct from Other Viruses but Similar to Hemophagocytic Syndromes

PubMed Central

Dunmire, Samantha K.; Odumade, Oludare A.; Porter, Jean L.; Reyes-Genere, Juan; Schmeling, David O.; Bilgic, Hatice; Fan, Danhua; Baechler, Emily C.; Balfour, Henry H.; Hogquist, Kristin A.

2014-01-01

Epstein-Barr Virus (EBV) causes infectious mononucleosis and establishes lifelong infection associated with cancer and autoimmune disease. To better understand immunity to EBV, we performed a prospective study of natural infection in healthy humans. Transcriptome analysis defined a striking and reproducible expression profile during acute infection but no lasting gene changes were apparent during latent infection. Comparing the EBV response profile to multiple other acute viral infections, including influenza A (influenza), respiratory syncytial virus (RSV), human rhinovirus (HRV), attenuated yellow fever virus (YFV), and Dengue fever virus (DENV), revealed similarity only to DENV. The signature shared by EBV and DENV was also present in patients with hemophagocytic syndromes, suggesting these two viruses cause uncontrolled inflammatory responses. Interestingly, while EBV induced a strong type I interferon response, a subset of interferon induced genes, including MX1, HERC5, and OAS1, were not upregulated, suggesting a mechanism by which viral antagonism of immunity results in a profound inflammatory response. These data provide an important first description of the response to a natural herpesvirus infection in humans. PMID:24465555

Primary EBV infection induces an expression profile distinct from other viruses but similar to hemophagocytic syndromes.

PubMed

Dunmire, Samantha K; Odumade, Oludare A; Porter, Jean L; Reyes-Genere, Juan; Schmeling, David O; Bilgic, Hatice; Fan, Danhua; Baechler, Emily C; Balfour, Henry H; Hogquist, Kristin A

2014-01-01

Epstein-Barr Virus (EBV) causes infectious mononucleosis and establishes lifelong infection associated with cancer and autoimmune disease. To better understand immunity to EBV, we performed a prospective study of natural infection in healthy humans. Transcriptome analysis defined a striking and reproducible expression profile during acute infection but no lasting gene changes were apparent during latent infection. Comparing the EBV response profile to multiple other acute viral infections, including influenza A (influenza), respiratory syncytial virus (RSV), human rhinovirus (HRV), attenuated yellow fever virus (YFV), and Dengue fever virus (DENV), revealed similarity only to DENV. The signature shared by EBV and DENV was also present in patients with hemophagocytic syndromes, suggesting these two viruses cause uncontrolled inflammatory responses. Interestingly, while EBV induced a strong type I interferon response, a subset of interferon induced genes, including MX1, HERC5, and OAS1, were not upregulated, suggesting a mechanism by which viral antagonism of immunity results in a profound inflammatory response. These data provide an important first description of the response to a natural herpesvirus infection in humans.

Exosomes released in vitro from Epstein-Barr virus (EBV)-infected cells contain EBV-encoded latent phase mRNAs.

PubMed

Canitano, Andrea; Venturi, Giulietta; Borghi, Martina; Ammendolia, Maria Grazia; Fais, Stefano

2013-09-01

EBV is a human herpesvirus associated with a number of malignancies. Both lymphoblastoid cell lines (LCLs), and EBV-infected nasopharyngeal carcinoma (NPC) cells have been demonstrated to release exosomes containing the EBV-encoded latent membrane protein 1 (LMP1), and mature micro-RNAs (EBV-miRNAs). Here we analyze the EBV protein and nucleic acid content of exosomes from different EBV-infected cells (LCL, 721 and Daudi) and we show for the first time that exosomes released from LCLs and 721 also contain EBV-encoded latent phase mRNAs. This confirms and strengthens exosomes pathogenetic potential, and might provide insights for development of novel diagnostic and therapeutic strategies. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

EBV Chronic Infections

PubMed Central

Eligio, Pizzigallo; Delia, Racciatti; Valeria, Gorgoretti

2010-01-01

The infection from Epstein-Barr virus (EBV) or virus of infectious mononucleosis, together with other herpes viruses’ infections, represents a prototype of persistent viral infections characterized by the property of the latency. Although the reactivations of the latent infection are associated with the resumption of the viral replication and eventually with the “shedding”, it is still not clear if this virus can determine chronic infectious diseases, more or less evolutive. These diseases could include some pathological conditions actually defined as “idiopathic”and characterized by the “viral persistence” as the more credible pathogenetic factor. Among the so-called idiopathic syndromes, the “chronic fatigue syndrome” (CFS) aroused a great interest around the eighties of the last century when, just for its relationship with EBV, it was called “chronic mononucleosis” or “chronic EBV infection”. Today CFS, as defined in 1994 by the CDC of Atlanta (USA), really represents a multifactorial syndrome characterized by a chronic course, where reactivation and remission phases alternate, and by a good prognosis. The etiopathogenetic role of EBV is demonstrated only in a well-examined subgroup of patients, while in most of the remaining cases this role should be played by other infectious agents - able to remain in a latent or persistent way in the host – or even by not infectious agents (toxic, neuroendocrine, methabolic, etc.). However, the pathogenetic substrate of the different etiologic forms seems to be the same, much probably represented by the oxidative damage due to the release of pro-inflammatory cytokines as a response to the triggering event (infectious or not infectious). Anyway, recently the scientists turned their’s attention to the genetic predisposition of the subjects affected by the syndrome, so that in the last years the genetic studies, together with those of molecular biology, received a great impulse. Thanks to both

The HSV-1 Latency-Associated Transcript Functions to Repress Latent Phase Lytic Gene Expression and Suppress Virus Reactivation from Latently Infected Neurons

PubMed Central

Nicoll, Michael P.; Hann, William; Shivkumar, Maitreyi; Harman, Laura E. R.; Connor, Viv; Coleman, Heather M.; Proença, João T.; Efstathiou, Stacey

2016-01-01

Herpes simplex virus 1 (HSV-1) establishes life-long latent infection within sensory neurons, during which viral lytic gene expression is silenced. The only highly expressed viral gene product during latent infection is the latency-associated transcript (LAT), a non-protein coding RNA that has been strongly implicated in the epigenetic regulation of HSV-1 gene expression. We have investigated LAT-mediated control of latent gene expression using chromatin immunoprecipitation analyses and LAT-negative viruses engineered to express firefly luciferase or β-galactosidase from a heterologous lytic promoter. Whilst we were unable to determine a significant effect of LAT expression upon heterochromatin enrichment on latent HSV-1 genomes, we show that reporter gene expression from latent HSV-1 genomes occurs at a greater frequency in the absence of LAT. Furthermore, using luciferase reporter viruses we have observed that HSV-1 gene expression decreases during long-term latent infection, with a most marked effect during LAT-negative virus infection. Finally, using a fluorescent mouse model of infection to isolate and culture single latently infected neurons, we also show that reactivation occurs at a greater frequency from cultures harbouring LAT-negative HSV-1. Together, our data suggest that the HSV-1 LAT RNA represses HSV-1 gene expression in small populations of neurons within the mouse TG, a phenomenon that directly impacts upon the frequency of reactivation and the maintenance of the transcriptionally active latent reservoir. PMID:27055281

Gammaherpesvirus Colonization of the Spleen Requires Lytic Replication in B Cells.

PubMed

Lawler, Clara; de Miranda, Marta Pires; May, Janet; Wyer, Orry; Simas, J Pedro; Stevenson, Philip G

2018-04-01

Gammaherpesviruses infect lymphocytes and cause lymphocytic cancers. Murid herpesvirus-4 (MuHV-4), Epstein-Barr virus, and Kaposi's sarcoma-associated herpesvirus all infect B cells. Latent infection can spread by B cell recirculation and proliferation, but whether this alone achieves systemic infection is unclear. To test the need of MuHV-4 for lytic infection in B cells, we flanked its essential ORF50 lytic transactivator with loxP sites and then infected mice expressing B cell-specific Cre (CD19-Cre). The floxed virus replicated normally in Cre - mice. In CD19-Cre mice, nasal and lymph node infections were maintained; but there was little splenomegaly, and splenic virus loads remained low. Cre-mediated removal of other essential lytic genes gave a similar phenotype. CD19-Cre spleen infection by intraperitoneal virus was also impaired. Therefore, MuHV-4 had to emerge lytically from B cells to colonize the spleen. An important role for B cell lytic infection in host colonization is consistent with the large CD8 + T cell responses made to gammaherpesvirus lytic antigens during infectious mononucleosis and suggests that vaccine-induced immunity capable of suppressing B cell lytic infection might reduce long-term virus loads. IMPORTANCE Gammaherpesviruses cause B cell cancers. Most models of host colonization derive from cell cultures with continuous, virus-driven B cell proliferation. However, vaccines based on these models have worked poorly. To test whether proliferating B cells suffice for host colonization, we inactivated the capacity of MuHV-4, a gammaherpesvirus of mice, to reemerge from B cells. The modified virus was able to colonize a first wave of B cells in lymph nodes but spread poorly to B cells in secondary sites such as the spleen. Consequently, viral loads remained low. These results were consistent with virus-driven B cell proliferation exploiting normal host pathways and thus having to transfer lytically to new B cells for new proliferation. We

Lytic bacteriophages

PubMed Central

Sharma, Manan

2013-01-01

Foodborne illnesses resulting from the consumption of produce commodities contaminated with enteric pathogens continue to be a significant public health issue. Lytic bacteriophages may provide an effective and natural intervention to reduce bacterial pathogens on fresh and fresh-cut produce commodities. The use of multi-phage cocktails specific for a single pathogen has been most frequently assessed on produce commodities to minimize the development of bacteriophage insensitive mutants (BIM) in target pathogen populations. Regulatory approval for the use of several lytic phage products specific for bacterial pathogens such as Escherichia coli O157:H7, Salmonella spp. and Listeria monocytogenes in foods and on food processing surfaces has been granted by various agencies in the US and other countries, possibly allowing for the more widespread use of bacteriophages in the decontamination of fresh and minimally processed produce. Research studies have shown lytic bacteriophages specific for E. coli O157:H7, Salmonella spp. and Listeria monocytogenes have been effective in reducing pathogen populations on leafy greens, sprouts and tomatoes. PMID:24228223

Autologous Epstein-Barr virus (EBV)-specific cytotoxic T cells for the treatment of persistent active EBV infection.

PubMed

Savoldo, Barbara; Huls, M Helen; Liu, Zhensheng; Okamura, Takayuki; Volk, Hans-Dieter; Reinke, Petra; Sabat, Robert; Babel, Nina; Jones, James F; Webster-Cyriaque, Jennifer; Gee, Adrian P; Brenner, Malcolm K; Heslop, Helen E; Rooney, Cliona M

2002-12-01

Chronic active Epstein-Barr virus (CAEBV) infection syndrome is a heterogeneous EBV-related disorder characterized by chronic fatigue, fever, lymphadenopathy, and/or hepatosplenomegaly, associated with abnormal patterns of antibody to EBV. CAEBV can range from disabling mild/moderate forms to rapidly lethal disorders. Even patients with mild/moderate disease frequently suffer adverse effects from long-term anti-inflammatory agents and have a quality of life that progressively deteriorates. It is still unknown why these individuals are unable to produce an effective immune response to control EBV, and no effective treatment is currently available. Since ex vivo-expanded EBV-specific cytotoxic T lymphocytes (EBV-CTLs) can safely restore EBV-specific cellular immune responses in immunodeficient patients, we assessed the possibility that adoptive immunotherapy might also effectively treat CAEBV infection. Following stimulation with irradiated EBV-transformed lymphoblastoid cell lines (LCLs), EBV-CTLs were successfully generated from 8 of 8 patients with the mild/moderate form of CAEBV infection. These CTLs were predominantly CD3(+) CD8(+) cells and produced specific killing of the autologous LCLs. There were 5 patients with 1- to 12-year histories of disease who were treated with 1 to 4 injections of EBV-CTLs. Following infusion, there was resolution of fatigue and malaise, disappearance of fever, and regression of lymphadenopathy and splenomegaly. The pattern and titers of anti-EBV antibodies also normalized. No toxicity was observed. There were 4 patients who did not show any relapse of disease within 6 to 36 months follow-up; one patient had recurrence of fatigue and myalgia one year after CTL infusion. We suggest that adoptive immunotherapy with autologous EBV-CTLs may represent a safe and feasible alternative treatment for patients affected with mild/moderate CAEBV infection and that this approach should be evaluated in the more severe forms of the disease.

Deep Sequencing Reveals Direct Targets of Gammaherpesvirus-Induced mRNA Decay and Suggests That Multiple Mechanisms Govern Cellular Transcript Escape

PubMed Central

Clyde, Karen; Glaunsinger, Britt A.

2011-01-01

One characteristic of lytic infection with gammaherpesviruses, including Kaposi's sarcoma-associated herpesvirus (KSHV), Epstein-Barr virus (EBV) and murine herpesvirus 68 (MHV68), is the dramatic suppression of cellular gene expression in a process known as host shutoff. The alkaline exonuclease proteins (KSHV SOX, MHV-68 muSOX and EBV BGLF5) have been shown to induce shutoff by destabilizing cellular mRNAs. Here we extend previous analyses of cellular mRNA abundance during lytic infection to characterize the effects of SOX and muSOX, in the absence of other viral genes, utilizing deep sequencing technology (RNA-seq). Consistent with previous observations during lytic infection, the majority of transcripts are downregulated in cells expressing either SOX or muSOX, with muSOX acting as a more potent shutoff factor than SOX. Moreover, most cellular messages fall into the same expression class in both SOX- and muSOX-expressing cells, indicating that both factors target similar pools of mRNAs. More abundant mRNAs are more efficiently downregulated, suggesting a concentration effect in transcript targeting. However, even among highly expressed genes there are mRNAs that escape host shutoff. Further characterization of select escapees reveals multiple mechanisms by which cellular genes can evade downregulation. While some mRNAs are directly refractory to SOX, the steady state levels of others remain unchanged, presumably as a consequence of downstream effects on mRNA biogenesis. Collectively, these studies lay the framework for dissecting the mechanisms underlying the susceptibility of mRNA to destruction during lytic gammaherpesvirus infection. PMID:21573023

Comparison of the prognostic impact of serum anti-EBV antibody and plasma EBV DNA assays in nasopharyngeal carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Twu, C.-W.; Department of Otorhinolaryngology, Taichung Veterans General Hospital, Taichung; Wang, W.-Y.

Purpose: Nasopharyngeal carcinoma (NPC) has been proven as an Epstein-Barr virus (EBV)-associated cancer. Serum anti-EBV antibodies and plasma EBV DNA have been investigated as surrogate markers for NPC. A comparison of the prognostic impacts of both assays has never been reported. Methods and Materials: Paired serum and plasma samples from 114 previously untreated NPC patients were collected and subjected to an immunofluorescence assay for immunoglobulin (Ig)A and IgG antibodies against the viral capsid antigen (VCA) and a real-time quantitative polymerase chain reaction assay for EBV DNA measurement. The effects of both assays on patient prognosis were thoroughly investigated. Results: Relapsedmore » patients had significantly higher pretreatment EBV DNA concentration than patients without relapse (p 0.0006). No associations of VCA-IgA (p = 0.9669) or VCA-IgG (p = 0.6125) were observed between patients with and without relapse. The 4-year overall survival (60.3% vs. 93.1%, p < 0.0001) and relapse-free survival rates (54.4% vs. 77.9%, p = 0.0009) were significantly lower in patients with higher pretreatment EBV DNA load than in those with lower EBV DNA load. Patients with persistently detectable EBV DNA after treatment had significantly worse 4-year overall (30.8% vs. 84.6%, p < 0.0001) and relapse-free survival rates (15.4% vs. 74.0%, p < 0.0001) than those with undetectable EBV DNA. The VCA-IgA and VCA-IgG titer could not predict survivals (all p > 0.1). Cox multivariate analyses also showed the same results. Conclusion: Plasma EBV DNA is superior to serum EBV VCA antibodies in prognostic predictions for NPC.« less

Phage lytic enzymes: a history.

PubMed

Trudil, David

2015-02-01

There are many recent studies regarding the efficacy of bacteriophage-related lytic enzymes: the enzymes of 'bacteria-eaters' or viruses that infect bacteria. By degrading the cell wall of the targeted bacteria, these lytic enzymes have been shown to efficiently lyse Gram-positive bacteria without affecting normal flora and non-related bacteria. Recent studies have suggested approaches for lysing Gram-negative bacteria as well (Briersa Y, et al., 2014). These enzymes include: phage-lysozyme, endolysin, lysozyme, lysin, phage lysin, phage lytic enzymes, phageassociated enzymes, enzybiotics, muralysin, muramidase, virolysin and designations such as Ply, PAE and others. Bacteriophages are viruses that kill bacteria, do not contribute to antimicrobial resistance, are easy to develop, inexpensive to manufacture and safe for humans, animals and the environment. The current focus on lytic enzymes has been on their use as anti-infectives in humans and more recently in agricultural research models. The initial translational application of lytic enzymes, however, was not associated with treating or preventing a specific disease but rather as an extraction method to be incorporated in a rapid bacterial detection assay (Bernstein D, 1997).The current review traces the translational history of phage lytic enzymes-from their initial discovery in 1986 for the rapid detection of group A streptococcus in clinical specimens to evolving applications in the detection and prevention of disease in humans and in agriculture.

CD44+ Cancer Stem-Like Cells in EBV-Associated Nasopharyngeal Carcinoma

PubMed Central

Lun, Samantha Wei-Man; Cheung, Siu Tim; Cheung, Phyllis Fung Yi; To, Ka-Fai; Woo, John Kong-Sang; Choy, Kwong-Wai; Chow, Chit; Cheung, Chartia Ching-Mei; Chung, Grace Tin-Yun; Cheng, Alice Suk-Hang; Ko, Chun-Wai; Tsao, Sai-Wah; Busson, Pierre; Ng, Margaret Heung-Ling; Lo, Kwok-Wai

2012-01-01

Nasopharyngeal carcinoma (NPC) is a unique EBV-associated epithelial malignancy, showing highly invasive and metastatic phenotype. Despite increasing evidence demonstrating the critical role of cancer stem-like cells (CSCs) in the maintenance and progression of tumors in a variety of malignancies, the existence and properties of CSC in EBV-associated NPC are largely unknown. Our study aims to elucidate the presence and role of CSCs in the pathogenesis of this malignant disease. Sphere-forming cells were isolated from an EBV-positive NPC cell line C666-1 and its tumor-initiating properties were confirmed by in vitro and in vivo assays. In these spheroids, up-regulation of multiple stem cell markers were found. By flow cytometry, we demonstrated that both CD44 and SOX2 were overexpressed in a majority of sphere-forming C666-1 cells. The CD44+SOX2+ cells was detected in a minor population in EBV-positive xenografts and primary tumors and considered as potential CSC in NPC. Notably, the isolated CD44+ NPC cells were resistant to chemotherapeutic agents and with higher spheroid formation efficiency, showing CSC properties. On the other hand, microarray analysis has revealed a number of differentially expressed genes involved in transcription regulation (e.g. FOXN4, GLI1), immune response (CCR7, IL8) and transmembrane transport (e.g. ABCC3, ABCC11) in the spheroids. Among these genes, increased expression of CCR7 in CD44+ CSCs was confirmed in NPC xenografts and primary tumors. Importantly, blocking of CCR7 abolished the sphere-forming ability of C666-1 in vitro. Expression of CCR7 was associated with recurrent disease and distant metastasis. The current study defined the specific properties of a CSC subpopulation in EBV-associated NPC. Our findings provided new insights into developing effective therapies targeting on CSCs, thereby potentiating treatment efficacy for NPC patients. PMID:23285037

Genome-wide analysis of wild-type Epstein-Barr virus genomes derived from healthy individuals of the 1,000 Genomes Project.

PubMed

Santpere, Gabriel; Darre, Fleur; Blanco, Soledad; Alcami, Antonio; Villoslada, Pablo; Mar Albà, M; Navarro, Arcadi

2014-04-01

Most people in the world (∼90%) are infected by the Epstein-Barr virus (EBV), which establishes itself permanently in B cells. Infection by EBV is related to a number of diseases including infectious mononucleosis, multiple sclerosis, and different types of cancer. So far, only seven complete EBV strains have been described, all of them coming from donors presenting EBV-related diseases. To perform a detailed comparative genomic analysis of EBV including, for the first time, EBV strains derived from healthy individuals, we reconstructed EBV sequences infecting lymphoblastoid cell lines (LCLs) from the 1000 Genomes Project. As strain B95-8 was used to transform B cells to obtain LCLs, it is always present, but a specific deletion in its genome sets it apart from natural EBV strains. After studying hundreds of individuals, we determined the presence of natural EBV in at least 10 of them and obtained a set of variants specific to wild-type EBV. By mapping the natural EBV reads into the EBV reference genome (NC007605), we constructed nearly complete wild-type viral genomes from three individuals. Adding them to the five disease-derived EBV genomic sequences available in the literature, we performed an in-depth comparative genomic analysis. We found that latency genes harbor more nucleotide diversity than lytic genes and that six out of nine latency-related genes, as well as other genes involved in viral attachment and entry into host cells, packaging, and the capsid, present the molecular signature of accelerated protein evolution rates, suggesting rapid host-parasite coevolution.

EBNA3C Directs Recruitment of RBPJ (CBF1) to Chromatin during the Process of Gene Repression in EBV Infected B Cells.

PubMed

Kalchschmidt, Jens S; Gillman, Adam C T; Paschos, Kostas; Bazot, Quentin; Kempkes, Bettina; Allday, Martin J

2016-01-01

It is well established that Epstein-Barr virus nuclear antigen 3C (EBNA3C) can act as a potent repressor of gene expression, but little is known about the sequence of events occurring during the repression process. To explore further the role of EBNA3C in gene repression-particularly in relation to histone modifications and cell factors involved-the three host genes previously reported as most robustly repressed by EBNA3C were investigated. COBLL1, a gene of unknown function, is regulated by EBNA3C alone and the two co-regulated disintegrin/metalloproteases, ADAM28 and ADAMDEC1 have been described previously as targets of both EBNA3A and EBNA3C. For the first time, EBNA3C was here shown to be the main regulator of all three genes early after infection of primary B cells. Using various EBV-recombinants, repression over orders of magnitude was seen only when EBNA3C was expressed. Unexpectedly, full repression was not achieved until 30 days after infection. This was accurately reproduced in established LCLs carrying EBV-recombinants conditional for EBNA3C function, demonstrating the utility of the conditional system to replicate events early after infection. Using this system, detailed chromatin immunoprecipitation analysis revealed that the initial repression was associated with loss of activation-associated histone modifications (H3K9ac, H3K27ac and H3K4me3) and was independent of recruitment of polycomb proteins and deposition of the repressive H3K27me3 modification, which were only observed later in repression. Most remarkable, and in contrast to current models of RBPJ in repression, was the observation that this DNA-binding factor accumulated at the EBNA3C-binding sites only when EBNA3C was functional. Transient reporter assays indicated that repression of these genes was dependent on the interaction between EBNA3C and RBPJ. This was confirmed with a novel EBV-recombinant encoding a mutant of EBNA3C unable to bind RBPJ, by showing this virus was incapable of

Prevalence and molecular profiling of Epstein Barr virus (EBV) among healthy blood donors from different nationalities in Qatar.

PubMed

Smatti, Maria K; Yassine, Hadi M; AbuOdeh, Raed; AlMarawani, Asmaa; Taleb, Sara A; Althani, Asmaa A; Nasrallah, Gheyath K

2017-01-01

The Epstein-Barr virus (EBV) is the causative agent of infectious mononucleosis. EBV is highly prevalent lymphotropic herpesvirus and has been linked to several malignancies. Transmission is generally by oral secretions, but can be through blood transfusions and organ transplantations. This study aimed to determine the seroprevalence, viremia rates, and circulating genotypes of EBV in healthy blood donors in Qatar. Blood samples from 673 blood donors of different nationalities residing in Qatar (mainly Qatar, Egypt, Syria, Jordan, Pakistan, and India) were collected and tested for anti-EBV capsid (VCA; IgG & IgM), nuclear (EBNA; IgG), and early (EA-D; IgG) antigens. Avidity testing was determined when active infection was suspected. DNA was extracted from the buffy coat and subjected to EBV-DNA quantification using qRT-PCR. Genotyping was performed using nested-PCR targeting EBV-EBNA2 gene, and phylogeny by sequence analysis of the LMP-1 gene. 97.9% (673/659) of the samples were seropositive as indicated by the presence VCA-IgG, while 52.6% (354/673) had detectible EBV-DNA. EBV seroprevalence and viremia rates increased significantly with age. Genotyping of 51 randomly selected samples showed predominance of Genotype 1 (72.5%, 37/51) as compared to genotype 2 (3.5%), and mixed infections were detected in 4% of the samples. Sub-genotyping for these samples revealed that the Mediterranean strain was predominant (65.3%), followed by B95.8 prototype and North Carolina strains (12.2% each), and China1 strain (6%). As a first study to evaluate EBV infection in highly diverse population in Qatar, where expatriates represent more than 85% of the population, our results indicated high seroprevalence and viremia rate of EBV in different nationalities, with genotype 1 and Mediterranean strain being predominant. Clinical significance of these finding have not been investigated and shall be evaluated in future studies.

[Potentialization of antibiotics by lytic enzymes].

PubMed

Brisou, J; Babin, P; Babin, R

1975-01-01

Few lytic enzymes, specially papaine and lysozyme, acting on the membrane and cell wall structures facilitate effects of bacitracine, streptomycine and other antibiotics. Streptomycino resistant strains became sensibles to this antibiotic after contact with papaine and lysozyme. The results of tests in physiological suspensions concern only the lytic activity of enzymes. The results on nutrient medium concern together lytic, and antibiotic activities.

EBV induces persistent NF-κB activation and contributes to survival of EBV-positive neoplastic T- or NK-cells.

PubMed

Takada, Honami; Imadome, Ken-Ichi; Shibayama, Haruna; Yoshimori, Mayumi; Wang, Ludan; Saitoh, Yasunori; Uota, Shin; Yamaoka, Shoji; Koyama, Takatoshi; Shimizu, Norio; Yamamoto, Kouhei; Fujiwara, Shigeyoshi; Miura, Osamu; Arai, Ayako

2017-01-01

Epstein-Barr virus (EBV) has been detected in several T- and NK-cell neoplasms such as extranodal NK/T-cell lymphoma nasal type, aggressive NK-cell leukemia, EBV-positive peripheral T-cell lymphoma, systemic EBV-positive T-cell lymphoma of childhood, and chronic active EBV infection (CAEBV). However, how this virus contributes to lymphomagenesis in T or NK cells remains largely unknown. Here, we examined NF-κB activation in EBV-positive T or NK cell lines, SNT8, SNT15, SNT16, SNK6, and primary EBV-positive and clonally proliferating T/NK cells obtained from the peripheral blood of patients with CAEBV. Western blotting, electrophoretic mobility shift assays, and immunofluorescent staining revealed persistent NF-κB activation in EBV-infected cell lines and primary cells from patients. Furthermore, we investigated the role of EBV in infected T cells. We performed an in vitro infection assay using MOLT4 cells infected with EBV. The infection directly induced NF-κB activation, promoted survival, and inhibited etoposide-induced apoptosis in MOLT4 cells. The luciferase assay suggested that LMP1 mediated NF-κB activation in MOLT4 cells. IMD-0354, a specific inhibitor of NF-κB that suppresses NF-κB activation in cell lines, inhibited cell survival and induced apoptosis. These results indicate that EBV induces NF-κB-mediated survival signals in T and NK cells, and therefore, may contribute to the lymphomagenesis of these cells.

EBV induces persistent NF-κB activation and contributes to survival of EBV-positive neoplastic T- or NK-cells

PubMed Central

Shibayama, Haruna; Yoshimori, Mayumi; Wang, Ludan; Saitoh, Yasunori; Uota, Shin; Yamaoka, Shoji; Koyama, Takatoshi; Shimizu, Norio; Yamamoto, Kouhei; Fujiwara, Shigeyoshi; Miura, Osamu

2017-01-01

Epstein–Barr virus (EBV) has been detected in several T- and NK-cell neoplasms such as extranodal NK/T-cell lymphoma nasal type, aggressive NK-cell leukemia, EBV-positive peripheral T-cell lymphoma, systemic EBV-positive T-cell lymphoma of childhood, and chronic active EBV infection (CAEBV). However, how this virus contributes to lymphomagenesis in T or NK cells remains largely unknown. Here, we examined NF-κB activation in EBV-positive T or NK cell lines, SNT8, SNT15, SNT16, SNK6, and primary EBV-positive and clonally proliferating T/NK cells obtained from the peripheral blood of patients with CAEBV. Western blotting, electrophoretic mobility shift assays, and immunofluorescent staining revealed persistent NF-κB activation in EBV-infected cell lines and primary cells from patients. Furthermore, we investigated the role of EBV in infected T cells. We performed an in vitro infection assay using MOLT4 cells infected with EBV. The infection directly induced NF-κB activation, promoted survival, and inhibited etoposide-induced apoptosis in MOLT4 cells. The luciferase assay suggested that LMP1 mediated NF-κB activation in MOLT4 cells. IMD-0354, a specific inhibitor of NF-κB that suppresses NF-κB activation in cell lines, inhibited cell survival and induced apoptosis. These results indicate that EBV induces NF-κB-mediated survival signals in T and NK cells, and therefore, may contribute to the lymphomagenesis of these cells. PMID:28346502

Translational profiling of B cells infected with the Epstein-Barr virus reveals 5' leader ribosome recruitment through upstream open reading frames.

PubMed

Bencun, Maja; Klinke, Olaf; Hotz-Wagenblatt, Agnes; Klaus, Severina; Tsai, Ming-Han; Poirey, Remy; Delecluse, Henri-Jacques

2018-04-06

The Epstein-Barr virus (EBV) genome encodes several hundred transcripts. We have used ribosome profiling to characterize viral translation in infected cells and map new translation initiation sites. We show here that EBV transcripts are translated with highly variable efficiency, owing to variable transcription and translation rates, variable ribosome recruitment to the leader region and coverage by monosomes versus polysomes. Some transcripts were hardly translated, others mainly carried monosomes, showed ribosome accumulation in leader regions and most likely represent non-coding RNAs. A similar process was visible for a subset of lytic genes including the key transactivators BZLF1 and BRLF1 in cells infected with weakly replicating EBV strains. This suggests that ribosome trapping, particularly in the leader region, represents a new checkpoint for the repression of lytic replication. We could identify 25 upstream open reading frames (uORFs) located upstream of coding transcripts that displayed 5' leader ribosome trapping, six of which were located in the leader region shared by many latent transcripts. These uORFs repressed viral translation and are likely to play an important role in the regulation of EBV translation.

Immune Activation and Benefit From Avelumab in EBV-Positive Gastric Cancer.

PubMed

Panda, Anshuman; Mehnert, Janice M; Hirshfield, Kim M; Riedlinger, Greg; Damare, Sherri; Saunders, Tracie; Kane, Michael; Sokol, Levi; Stein, Mark N; Poplin, Elizabeth; Rodriguez-Rodriguez, Lorna; Silk, Ann W; Aisner, Joseph; Chan, Nancy; Malhotra, Jyoti; Frankel, Melissa; Kaufman, Howard L; Ali, Siraj; Ross, Jeffrey S; White, Eileen P; Bhanot, Gyan; Ganesan, Shridar

2018-03-01

Response to immune checkpoint therapy can be associated with a high mutation burden, but other mechanisms are also likely to be important. We identified a patient with metastatic gastric cancer with meaningful clinical benefit from treatment with the anti-programmed death-ligand 1 (PD-L1) antibody avelumab. This tumor showed no evidence of high mutation burden or mismatch repair defect but was strongly positive for presence of Epstein-Barr virus (EBV) encoded RNA. Analysis of The Cancer Genome Atlas gastric cancer data (25 EBV+, 80 microsatellite-instable [MSI], 310 microsatellite-stable [MSS]) showed that EBV-positive tumors were MSS. Two-sided Wilcoxon rank-sum tests showed that: 1) EBV-positive tumors had low mutation burden (median = 2.07 vs 3.13 in log10 scale, P < 10-12) but stronger evidence of immune infiltration (median ImmuneScore 2212 vs 1295, P < 10-4; log2 fold-change of CD8A = 1.85, P < 10-6) compared with MSI tumors, and 2) EBV-positive tumors had higher expression of immune checkpoint pathway (PD-1, CTLA-4 pathway) genes in RNA-seq data (log2 fold-changes: PD-1 = 1.85, PD-L1 = 1.93, PD-L2 = 1.50, CTLA-4 = 1.31, CD80 = 0.89, CD86 = 1.31, P < 10-4 each), and higher lymphocytic infiltration by histology (median tumor-infiltrating lymphocyte score = 3 vs 2, P < .001) compared with MSS tumors. These data suggest that EBV-positive low-mutation burden gastric cancers are a subset of MSS gastric cancers that may respond to immune checkpoint therapy.

Glycolysis, Glutaminolysis, and Fatty Acid Synthesis Are Required for Distinct Stages of Kaposi's Sarcoma-Associated Herpesvirus Lytic Replication.

PubMed

Sanchez, Erica L; Pulliam, Thomas H; Dimaio, Terri A; Thalhofer, Angel B; Delgado, Tracie; Lagunoff, Michael

2017-05-15

Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiologic agent of Kaposi's sarcoma (KS). KSHV infection induces and requires multiple metabolic pathways, including the glycolysis, glutaminolysis, and fatty acid synthesis (FAS) pathways, for the survival of latently infected endothelial cells. To determine the metabolic requirements for productive KSHV infection, we induced lytic replication in the presence of inhibitors of different metabolic pathways. We found that glycolysis, glutaminolysis, and FAS are all required for maximal KSHV virus production and that these pathways appear to participate in virus production at different stages of the viral life cycle. Glycolysis and glutaminolysis, but not FAS, inhibit viral genome replication and, interestingly, are required for different early steps of lytic gene expression. Glycolysis is necessary for early gene transcription, while glutaminolysis is necessary for early gene translation but not transcription. Inhibition of FAS resulted in decreased production of extracellular virions but did not reduce intracellular genome levels or block intracellular virion production. However, in the presence of FAS inhibitors, the intracellular virions are noninfectious, indicating that FAS is required for virion assembly or maturation. KS tumors support both latent and lytic KSHV replication. Previous work has shown that multiple cellular metabolic pathways are required for latency, and we now show that these metabolic pathways are required for efficient lytic replication, providing novel therapeutic avenues for KS tumors. IMPORTANCE KSHV is the etiologic agent of Kaposi's sarcoma, the most common tumor of AIDS patients. KS spindle cells, the main tumor cells, all contain KSHV, mostly in the latent state, during which there is limited viral gene expression. However, a percentage of spindle cells support lytic replication and production of virus and these cells are thought to contribute to overall tumor formation. Our

Glycolysis, Glutaminolysis, and Fatty Acid Synthesis Are Required for Distinct Stages of Kaposi's Sarcoma-Associated Herpesvirus Lytic Replication

PubMed Central

Sanchez, Erica L.; Pulliam, Thomas H.; Dimaio, Terri A.; Thalhofer, Angel B.; Delgado, Tracie

2017-01-01

ABSTRACT Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiologic agent of Kaposi's sarcoma (KS). KSHV infection induces and requires multiple metabolic pathways, including the glycolysis, glutaminolysis, and fatty acid synthesis (FAS) pathways, for the survival of latently infected endothelial cells. To determine the metabolic requirements for productive KSHV infection, we induced lytic replication in the presence of inhibitors of different metabolic pathways. We found that glycolysis, glutaminolysis, and FAS are all required for maximal KSHV virus production and that these pathways appear to participate in virus production at different stages of the viral life cycle. Glycolysis and glutaminolysis, but not FAS, inhibit viral genome replication and, interestingly, are required for different early steps of lytic gene expression. Glycolysis is necessary for early gene transcription, while glutaminolysis is necessary for early gene translation but not transcription. Inhibition of FAS resulted in decreased production of extracellular virions but did not reduce intracellular genome levels or block intracellular virion production. However, in the presence of FAS inhibitors, the intracellular virions are noninfectious, indicating that FAS is required for virion assembly or maturation. KS tumors support both latent and lytic KSHV replication. Previous work has shown that multiple cellular metabolic pathways are required for latency, and we now show that these metabolic pathways are required for efficient lytic replication, providing novel therapeutic avenues for KS tumors. IMPORTANCE KSHV is the etiologic agent of Kaposi's sarcoma, the most common tumor of AIDS patients. KS spindle cells, the main tumor cells, all contain KSHV, mostly in the latent state, during which there is limited viral gene expression. However, a percentage of spindle cells support lytic replication and production of virus and these cells are thought to contribute to overall tumor formation

Mutations of amino acids in the DNA-recognition domain of Epstein-Barr virus ZEBRA protein alter its sub-nuclear localization and affect formation of replication compartments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Richard; Heston, Lee; Shedd, Duane

ZEBRA, a transcription factor and DNA replication protein encoded by the Epstein-Barr virus (EBV) BZLF1 gene, plays indispensable roles in the EBV lytic cycle. We recently described the phenotypes of 46 single amino acid substitutions introduced into the DNA-recognition region of ZEBRA [Heston, L., El-Guindy, A., Countryman, J., Dela Cruz, C., Delecluse, H.J., and Miller, G. 2006]. The 27 DNA-binding-proficient mutants exhibited distinct defects in their ability to activate expression of the kinetic classes of viral genes. Four phenotypic variants could be discerned: wild-type, defective at activating Rta, defective at activating early genes, and defective at activating late genes. Heremore » we analyze the distribution of ZEBRA within the nucleus and the localization of EA-D (the viral DNA polymerase processivity factor), an indicator of the development of replication compartments, in representatives of each phenotypic group. Plasmids encoding wild-type (WT) and mutant ZEBRA were transfected into 293 cells containing EBV-bacmids. WT ZEBRA protein was diffusely and smoothly distributed throughout the nucleus, sparing nucleoli, and partially recruited to globular replication compartments. EA-D induced by WT ZEBRA was present diffusely in some cells and concentrated in globular replication compartments in other cells. The distribution of ZEBRA and EA-D proteins was identical to WT following transfection of K188R, a mutant with a conservative change. The distribution of S186A mutant ZEBRA protein, defective for activation of Rta and EA-D, was identical to WT, except that the mutant ZEBRA was never found in globular compartments. Co-expression of Rta with S186A mutant rescued diffuse EA-D but not globular replication compartments. The most striking observation was that several mutant ZEBRA proteins defective in activating EA-D (R179A, K181A and A185V) and defective in activating lytic viral DNA replication and late genes (Y180E and K188A) were localized to numerous

Prevalence and molecular profiling of Epstein Barr virus (EBV) among healthy blood donors from different nationalities in Qatar

PubMed Central

Smatti, Maria K.; Yassine, Hadi M.; AbuOdeh, Raed; AlMarawani, Asmaa; Taleb, Sara A.; Althani, Asmaa A.

2017-01-01

Background The Epstein–Barr virus (EBV) is the causative agent of infectious mononucleosis. EBV is highly prevalent lymphotropic herpesvirus and has been linked to several malignancies. Transmission is generally by oral secretions, but can be through blood transfusions and organ transplantations. This study aimed to determine the seroprevalence, viremia rates, and circulating genotypes of EBV in healthy blood donors in Qatar. Methods Blood samples from 673 blood donors of different nationalities residing in Qatar (mainly Qatar, Egypt, Syria, Jordan, Pakistan, and India) were collected and tested for anti-EBV capsid (VCA; IgG & IgM), nuclear (EBNA; IgG), and early (EA-D; IgG) antigens. Avidity testing was determined when active infection was suspected. DNA was extracted from the buffy coat and subjected to EBV-DNA quantification using qRT-PCR. Genotyping was performed using nested-PCR targeting EBV-EBNA2 gene, and phylogeny by sequence analysis of the LMP-1 gene. Results 97.9% (673/659) of the samples were seropositive as indicated by the presence VCA-IgG, while 52.6% (354/673) had detectible EBV-DNA. EBV seroprevalence and viremia rates increased significantly with age. Genotyping of 51 randomly selected samples showed predominance of Genotype 1 (72.5%, 37/51) as compared to genotype 2 (3.5%), and mixed infections were detected in 4% of the samples. Sub-genotyping for these samples revealed that the Mediterranean strain was predominant (65.3%), followed by B95.8 prototype and North Carolina strains (12.2% each), and China1 strain (6%). Conclusion As a first study to evaluate EBV infection in highly diverse population in Qatar, where expatriates represent more than 85% of the population, our results indicated high seroprevalence and viremia rate of EBV in different nationalities, with genotype 1 and Mediterranean strain being predominant. Clinical significance of these finding have not been investigated and shall be evaluated in future studies. PMID:29228016

Clonal origin of Epstein-Barr virus (EBV)-infected T/NK-cell subpopulations in EBV-positive T/NK-cell lymphoproliferative disorders of childhood.

PubMed

Ohga, Shouichi; Ishimura, Masataka; Yoshimoto, Goichi; Miyamoto, Toshihiro; Takada, Hidetoshi; Tanaka, Tamami; Ohshima, Koichi; Ogawa, Yoshiyasu; Imadome, Ken-Ichi; Abe, Yasunobu; Akashi, Koichi; Hara, Toshiro

2011-05-01

In Japan, chronic active Epstein-Barr virus infection (CAEBV) may manifest with infection of T-cells or NK-cells, clonal lymphoid proliferations, and overt lymphoid malignancy. These EBV-positive lymphoproliferative disorders (EBV(+)LPD) of childhood are related to, but distinct from the infectious mononucleosis-like CAEBV seen in Western populations. The clonal nature of viral infection within lymphoid subsets of patients with EBV(+)LPD of childhood is not well described. Viral distribution and clonotype were assessed within T-cell subsets, NK-cells, and CD34(+)stem cells following high purity cell sorting. Six Japanese patients with EBV(+)LPD of childhood (3 T-cell LPD and 3 NK-cell LPD) were recruited. Prior to immunochemotherapy, viral loads and clonal analyses of T-cell subsets, NK-cells, and CD34(+)stem cells were studied by high-accuracy cell sorting (>99.5%), Southern blotting and real-time polymerase chain reaction. Patient 1 had a monoclonal proliferation of EBV-infected γδT-cells and carried a lower copy number of EBV in αβT-cells. Patients 2 and 3 had clonal expansions of EBV-infected CD4(+)T-cells, and lower EBV load in NK-cells. Patients 4, 5 and 6 had EBV(+)NK-cell expansions with higher EBV load than T-cells. EBV-terminal repeats were determined as clonal bands in the minor targeted populations of 5 patients. The size of terminal repeats indicated the same clonotype in minor subsets as in the major subsets of four patients. EBV was not, however, detected in the bone marrow-derived CD34(+)stem cells of patients. A single EBV clonotype may infect multiple NK-cell and T-cell subsets of patients with EBV(+)LPD of childhood. CD34(+)stem cells are spared, suggesting infection of more differentiated elements. Copyright © 2011 Elsevier B.V. All rights reserved.

Epstein-Barr virus (EBV) load in cerebrospinal fluid and peripheral blood of patients with EBV-associated central nervous system diseases after allogeneic hematopoietic stem cell transplantation.

PubMed

Liu, Q-F; Ling, Y-W; Fan, Z-P; Jiang, Q-L; Sun, J; Wu, X-L; Zhao, J; Wei, Q; Zhang, Y; Yu, G-P; Wu, M-Q; Feng, R

2013-08-01

To evaluate the diagnostic and prognostic utility of monitoring the Epstein-Barr virus (EBV) load in the cerebrospinal fluid (CSF) and peripheral blood for the patients with EBV-associated central nervous system (CNS) diseases after allogeneic hematopoietic stem cell transplantation (allo-HSCT), 172 patients undergoing allo-HSCT were enrolled in the study. The EBV DNA levels of blood were monitored regularly in recipients of transplants for 3 years post transplantation. The EBV DNA levels of CSF were monitored in patients with EBV-associated CNS diseases before the treatment and at different points following the treatment. Post-transplant EBV-associated diseases developed in 27 patients, including 12 patients with EBV-associated CNS diseases. The 3-year cumulative incidences of EBV-associated diseases and EBV-associated CNS diseases were 19.5 ± 3.5% and 8.6 ± 2.4%, respectively. Patients with EBV-associated diseases showed higher loads of EBV DNA in their blood compared with patients with EBV DNA-emia. No difference was seen between the EBV DNA levels of blood in patients with CNS involvement and patients without CNS involvement. The EBV DNA loads of blood increased 3-14 days before the clinical manifestations of EBV-associated diseases emerged. The EBV DNA loads of CSF were higher than that of blood in patients with EBV-associated CNS diseases. In 12 patients with EBV-associated CNS diseases, EBV DNA levels were declining in both blood and CSF with the control of diseases, and the EBV DNA loads of CSF decreased faster than that of blood in 5 patients who responded to treatment, and the EBV DNA levels of CSF increased in 5 patients who were unresponsive to treatment. On multivariate analysis, the use of anti-thymocyte globulin and intensified conditioning regimens were independent risk factors for EBV-associated diseases and EBV-associated CNS diseases. EBV-associated CNS diseases are not rare after allo-HSCT. The EBV DNA loads of CSF could act as an important

Establishment and characterization of a novel Hodgkin lymphoma cell line, AM-HLH, carrying the Epstein-Barr virus genome integrated into the host chromosome.

PubMed

Hayashida, Masahiko; Daibata, Masanori; Tagami, Erika; Taguchi, Takahiro; Maekawa, Fumiyo; Takeoka, Kayo; Fukutsuka, Katsuhiro; Shimomura, Daiki; Hayashi, Takamasa; Iwatani, Yoshinori; Ohno, Hitoshi

2017-12-01

We describe the establishment and characterization of a cell line, AM-HLH, obtained from a patient with Epstein-Barr virus-positive (EBV + ) nodular sclerosis-type Hodgkin lymphoma (HL). The cells were positive for CD2 and CD30 and negative for CD15. The immunoglobulin heavy- and κ light-chain genes were rearranged. The karyotype was of the triploid range. Southern blotting using the EBV terminal repeat probe detected 3 hybridizing bands that were identical to those of the parental HL material. The cells expressed EBV-encoded RNAs as well as latent genes (EBNA1, EBNA2, LMP1, and LMP2A) and lytic genes (BZLF1 and BALF2). Fluorescence in situ hybridization (FISH) with the cosmid pJB8 clone containing a fragment of EBV DNA as a probe revealed multiple hybridization signals at a marker chromosome. Additional FISH using whole chromosome painting and centromere probes in combination with multicolor FISH determined that multiple EBV copies were clustered within the chromosome 20 materials of the marker chromosome. Culture supernatants of AM-HLH contained IL-10 as measured by the bead-based immunoassay. It is possible that an integrated EBV genome and cellular genes on chromosome 20 were coamplified, leading to the enhanced expression of genes involved in cell growth control. The AM-HLH cell line will be useful to clarify the role of cytokines in the development of EBV + HL. Copyright © 2016 John Wiley & Sons, Ltd.

Biclonal expansion of T cells infected with monoclonal Epstein–Barr virus (EBV) in a patient with chronic, active EBV infection

PubMed Central

TOYABE, S; HARADA, W; UCHIYAMA, M

2003-01-01

Recent studies have suggested that a high percentage of Epstein–Barr virus (EBV)-infected lymphocytes in peripheral blood of patients with chronic, active EBV infection (CAEBV) is of T cell origin. Although T cells are expanded oligoclonally in CAEBV, it is not clear whether the restricted diversity of T cells arise from immune reaction against EBV-related antigens or from proliferation of EBV-infected cells. We experienced a patient with CAEBV who had biclonal expansion of peripheral blood T cells. We identified clonotypes of these two T cell clones in detail and purified the T cell clones. EBV infected mainly the two T cell clones, whereas the viral loads in peripheral blood cells other than these T cell clones were low or undetectable. The EBV strains infecting the two T cells clones were indistinguishable from each other by a series of genotype analyses of the virus. These results suggest that the two T cell clones infected with the same monoclonal EBV proliferated in peripheral blood of the patient. PMID:12974760

Anti-tumor effects of suberoylanilide hydroxamic acid on Epstein–Barr virus-associated T cell and natural killer cell lymphoma

PubMed Central

Siddiquey, Mohammed NA; Nakagawa, Hikaru; Iwata, Seiko; Kanazawa, Tetsuhiro; Suzuki, Michio; Imadome, Ken-Ichi; Fujiwara, Shigeyoshi; Goshima, Fumi; Murata, Takayuki; Kimura, Hiroshi

2014-01-01

The ubiquitous Epstein–Barr virus (EBV) infects not only B cells but also T cells and natural killer (NK) cells and is associated with various lymphoid malignancies. Recent studies have reported that histone deacetylase (HDAC) inhibitors exert anticancer effects against various tumor cells. In the present study, we have evaluated both the in vitro and in vivo effects of suberoylanilide hydroxamic acid (SAHA), an HDAC inhibitor, on EBV-positive and EBV-negative T and NK lymphoma cells. Several EBV-positive and EBV-negative T and NK cell lines were treated with various concentrations of SAHA. SAHA suppressed the proliferation of T and NK cell lines, although no significant difference was observed between EBV-positive and EBV-negative cell lines. SAHA induced apoptosis and/or cell cycle arrest in several T and NK cell lines. In addition, SAHA increased the expression of EBV-lytic genes and decreased the expression of EBV-latent genes. Next, EBV-positive NK cell lymphoma cells were subcutaneously inoculated into severely immunodeficient NOD/Shi-scid/IL-2Rγnull mice, and then SAHA was administered intraperitoneally. SAHA inhibited tumor progression and metastasis in the murine xenograft model. SAHA displayed a marked suppressive effect against EBV-associated T and NK cell lymphomas through either induction of apoptosis or cell cycle arrest, and may represent an alternative treatment option. PMID:24712440

Proposed categorization of pathological states of EBV-associated T/natural killer-cell lymphoproliferative disorder (LPD) in children and young adults: overlap with chronic active EBV infection and infantile fulminant EBV T-LPD.

PubMed

Ohshima, Koichi; Kimura, Hiroshi; Yoshino, Tadashi; Kim, Chul Woo; Ko, Young H; Lee, Seung-Suk; Peh, Suat-Cheng; Chan, John K C

2008-04-01

EBV-associated T/natural killer (NK)-cell lymphoproliferative disorder (EBV-T/NK LPD) of children and young adults is generally referred to with the blanket nosological term of severe chronic active EBV infection (CAEBV). This disease is rare, associated with high morbidity and mortality, and appears to be more prevalent in East Asian countries. But because there is no grading or categorization system for CAEBV, pathologists and clinicians often disagree regarding diagnosis and therapy. EBV-T/NK LPD includes polyclonal, oligoclonal, and monoclonal proliferation of cytotoxic T and/or NK cells. Moreover, a unique disease previously described as infantile fulminant EBV-associated T-LPD has been identified and overlaps with EBV-T/NK LPD. In the present review a clinicopathological categorization of EBV-T/NK LPD is proposed, based on pathological evaluation and molecular data, as follows: (i) category A1, polymorphic LPD without clonal proliferation of EBV-infected cells; (ii) category A2, polymorphic LPD with clonality; (iii) category A3, monomorphic LPD (T-cell or NK cell lymphoma/leukemia) with clonality; and (iv) category B, monomorphic LPD (T-cell lymphoma) with clonality and fulminant course. Categories A1, A2, and A3 possibly constitute a continuous spectrum and together are equivalent to CAEBV. Category B is the exact equivalent of infantile fulminant EBV-associated T-LPD. It is expected that this categorization system will provide a guide for the better understanding of this disorder. This proposal was approved at the third meeting of the Asian Hematopathology Association (Nagoya, 2006).

Determining EBV load: current best practice and future requirements.

PubMed

Ruf, Stephanie; Wagner, Hans-Joachim

2013-02-01

EBV, a gammaherpesvirus and the pathogenic agent for infectious mononucleosis, is also associated with a broad spectrum of lymphoid and epithelial malignancies in immunocompetent and immunosuppressed individuals. EBV-DNA-load measurement by PCR has been shown to be a potential tool for the diagnosis of these diseases, a prognostic factor of their outcome and a successful method to monitor immunosuppressed patients. Since the end of 2011, there is an international WHO standard reference for EBV quantification available; however, many questions still remain; for instance about the optimal amplified region of the EBV genome, or the best-used specimen for EBV detection. Additionally, the optimal specimen and amplified region may vary in different malignancies. In this article, the authors review the different methods to measure EBV load, focus on the best-used specimen for the different EBV-associated malignancies and discuss future requirements and opportunities for EBV-load measurement.

The Epstein-Barr virus DNA load in the peripheral blood of transplant recipients does not accurately reflect the burden of infected cells.

PubMed

Fink, Susanne; Tsai, Ming-Han; Schnitzler, Paul; Zeier, Martin; Dreger, Peter; Wuchter, Patrick; Bulut, Olcay C; Behrends, Uta; Delecluse, Henri-Jacques

2017-01-01

Transplant recipients frequently exhibit an increased Epstein-Barr virus (EBV) load in the peripheral blood. Here, we quantitated the EBV-infected cells in the peripheral blood of these patients and defined the mode of viral infection, latent or lytic. These data indicated that there is no strong correlation between the number of infected cells and the EBV load (EBVL). This can be explained by a highly variable number of EBV copies per infected cell and by lytic replication in some cells. The plasma of these patients did not contain any free infectious viruses, but contained nevertheless EBV DNA, sometimes in large amounts, that probably originates from cell debris and contributed to the total EBVL. Some of the investigated samples carried a highly variable number of infected cells in active latency, characterized by an expression of the Epstein-Barr nuclear antigens (EBNA2) protein. However, a third of the samples expressed neither EBNA2 nor lytic proteins. Patients with an increased EBVL represent a heterogeneous group of patients whose infection cannot be characterized by this method alone. Precise characterization of the origin of an increased EBVL, in particular, in terms of the number of EBV-infected cells, requires additional investigations including the number of EBV-encoded small RNA-positive cells. © 2016 Steunstichting ESOT.

Cloning and Expression Analysis of Genes Encoding Lytic Endopeptidases L1 and L5 from Lysobacter sp. Strain XL1

PubMed Central

Lapteva, Y. S.; Zolova, O. E.; Shlyapnikov, M. G.; Tsfasman, I. M.; Muranova, T. A.; Stepnaya, O. A.; Kulaev, I. S.

2012-01-01

Lytic enzymes are the group of hydrolases that break down structural polymers of the cell walls of various microorganisms. In this work, we determined the nucleotide sequences of the Lysobacter sp. strain XL1 alpA and alpB genes, which code for, respectively, secreted lytic endopeptidases L1 (AlpA) and L5 (AlpB). In silico analysis of their amino acid sequences showed these endopeptidases to be homologous proteins synthesized as precursors similar in structural organization: the mature enzyme sequence is preceded by an N-terminal signal peptide and a pro region. On the basis of phylogenetic analysis, endopeptidases AlpA and AlpB were assigned to the S1E family [clan PA(S)] of serine peptidases. Expression of the alpA and alpB open reading frames (ORFs) in Escherichia coli confirmed that they code for functionally active lytic enzymes. Each ORF was predicted to have the Shine-Dalgarno sequence located at a canonical distance from the start codon and a potential Rho-independent transcription terminator immediately after the stop codon. The alpA and alpB mRNAs were experimentally found to be monocistronic; transcription start points were determined for both mRNAs. The synthesis of the alpA and alpB mRNAs was shown to occur predominantly in the late logarithmic growth phase. The amount of alpA mRNA in cells of Lysobacter sp. strain XL1 was much higher, which correlates with greater production of endopeptidase L1 than of L5. PMID:22865082

Cloning and expression analysis of genes encoding lytic endopeptidases L1 and L5 from Lysobacter sp. strain XL1.

PubMed

Lapteva, Y S; Zolova, O E; Shlyapnikov, M G; Tsfasman, I M; Muranova, T A; Stepnaya, O A; Kulaev, I S; Granovsky, I E

2012-10-01

Lytic enzymes are the group of hydrolases that break down structural polymers of the cell walls of various microorganisms. In this work, we determined the nucleotide sequences of the Lysobacter sp. strain XL1 alpA and alpB genes, which code for, respectively, secreted lytic endopeptidases L1 (AlpA) and L5 (AlpB). In silico analysis of their amino acid sequences showed these endopeptidases to be homologous proteins synthesized as precursors similar in structural organization: the mature enzyme sequence is preceded by an N-terminal signal peptide and a pro region. On the basis of phylogenetic analysis, endopeptidases AlpA and AlpB were assigned to the S1E family [clan PA(S)] of serine peptidases. Expression of the alpA and alpB open reading frames (ORFs) in Escherichia coli confirmed that they code for functionally active lytic enzymes. Each ORF was predicted to have the Shine-Dalgarno sequence located at a canonical distance from the start codon and a potential Rho-independent transcription terminator immediately after the stop codon. The alpA and alpB mRNAs were experimentally found to be monocistronic; transcription start points were determined for both mRNAs. The synthesis of the alpA and alpB mRNAs was shown to occur predominantly in the late logarithmic growth phase. The amount of alpA mRNA in cells of Lysobacter sp. strain XL1 was much higher, which correlates with greater production of endopeptidase L1 than of L5.

Primary EBV infection of human umbilical cord lymphocytes and EBV genome-negative lymphoblastoid cell lines (BJAB and Ramos).

PubMed

Takimoto, T; Sato, H; Ogura, H

1986-01-01

The appearance of Epstein-Barr virus (EBV)-associated nuclear antigen (EBNA) and induction of EBV-induced early antigen (EA) in human umbilical cord blood lymphocytes (HUCLs) and two EBV genome-negative Burkitt's lymphoma (BL) lines (BJAB and Ramos) were studied by infection with EBVs prepared from three different cell lines: marmoset cell line (B95-8) derived from infections mononucleosis, BL-derived cell line (P3HR-1) and human epithelial hybrid cell line (NPC-KT) derived from nasopharyngeal carcinoma. B95-8 virus can transform HUCLs but cannot superinfect Raji cells. P3HR-1 virus can transform HUCLs cells but cannot transform HUCLs. NPC-KT virus can transform HUCLs and can superinfect Raji cells. We have examined the time sequence of EBNA appearance and EA induction in HUCLs, BJAB cells and Ramos cells, in order to determine if three different strains of EBV differ in their abilities to infect their cells. We found that all three strains of EBV can induce EBNA in HUCLs, BJAB cells and Ramos cells. On the other hand, we found that P3HR-1 virus and NPC-KT virus can induce EA in BJAB cells and Ramos cells, but B95-8 virus cannot induce EA in their cells.

Inflammation and Epstein-Barr Virus Infection Are Common Features of Myasthenia Gravis Thymus: Possible Roles in Pathogenesis

PubMed Central

Cavalcante, Paola; Maggi, Lorenzo; Colleoni, Lara; Caldara, Rosa; Motta, Teresio; Giardina, Carmelo; Antozzi, Carlo; Berrih-Aknin, Sonia; Bernasconi, Pia; Mantegazza, Renato

2011-01-01

The thymus plays a major role in myasthenia gravis (MG). Our recent finding of a persistent Epstein-Barr (EBV) virus infection in some MG thymuses, combined with data showing that the thymus is in a proinflammatory state in most patients, supports a viral contribution to the pathogenesis of MG. Aim of this study was to gain further evidence for intrathymic chronic inflammation and EBV infection in MG patients. Transcriptional profiling by low density array and real-time PCR showed overexpression of genes involved in inflammatory and immune response in MG thymuses. Real-time PCR for EBV genome, latent (EBER1, EBNA1, LMP1) and lytic (BZLF1) transcripts, and immunohistochemistry for LMP1 and BZLF1 proteins confirmed an active intrathymic EBV infection, further supporting the hypothesis that EBV might contribute to onset or perpetuation of the autoimmune response in MG. Altogether, our results support a role of inflammation and EBV infection as pathogenic features of MG thymus. PMID:21961056

Toward Understanding Phage:Host Interactions in the Rumen; Complete Genome Sequences of Lytic Phages Infecting Rumen Bacteria

PubMed Central

Gilbert, Rosalind A.; Kelly, William J.; Altermann, Eric; Leahy, Sinead C.; Minchin, Catherine; Ouwerkerk, Diane; Klieve, Athol V.

2017-01-01

The rumen is known to harbor dense populations of bacteriophages (phages) predicted to be capable of infecting a diverse range of rumen bacteria. While bacterial genome sequencing projects are revealing the presence of phages which can integrate their DNA into the genome of their host to form stable, lysogenic associations, little is known of the genetics of phages which utilize lytic replication. These phages infect and replicate within the host, culminating in host lysis, and the release of progeny phage particles. While lytic phages for rumen bacteria have been previously isolated, their genomes have remained largely uncharacterized. Here we report the first complete genome sequences of lytic phage isolates specifically infecting three genera of rumen bacteria: Bacteroides, Ruminococcus, and Streptococcus. All phages were classified within the viral order Caudovirales and include two phage morphotypes, representative of the Siphoviridae and Podoviridae families. The phage genomes displayed modular organization and conserved viral genes were identified which enabled further classification and determination of closest phage relatives. Co-examination of bacterial host genomes led to the identification of several genes responsible for modulating phage:host interactions, including CRISPR/Cas elements and restriction-modification phage defense systems. These findings provide new genetic information and insights into how lytic phages may interact with bacteria of the rumen microbiome. PMID:29259581

Increased EBV Shedding in Astronaut Saliva During Spaceflight

NASA Technical Reports Server (NTRS)

Pierson, D. L.; Stowe, R. P.; Phillips, T.; Lugg, D. J.; Mehta, S. K.

2003-01-01

Shedding of Epstein-Barr virus (EBV) by astronauts before, during, and after space shuttle missions was quantified. Of 1398 saliva specimens from 32 astronauts, 314 (23%) were positive for EBV DNA by PCR analysis. Of the saliva specimens collected before flight, 29% were positive for EBV DNA and of those collected during or after flight, 16% were EBV-positive. The number of EBV DNA copies from samples taken during the flight was 417+/-31, significantly higher (P < 0.05) than the number of copies from the preflight (40+/-1.7) and postflight (44+/-5) phases. Eighteen control subjects shed EBV DNA with a frequency of 3.7% and a copy number of 40+/-2 per ml saliva. Ten days before flight and on landing day, antibody titers to EBV viral capsid antigen (VCA) were significantly (P < 0.05) higher than baseline levels. On landing day, urinary level of cortiso1 and catecholamines, and plasma levels of substance P and other neuropeptides, were increased over their preflight value. Results suggested that stress associated with spaceflight decreases cellular immunity and thereby leads to increased viral reactivation.

Epstein-Barr Virus Hijacks DNA Damage Response Transducers to Orchestrate Its Life Cycle.

PubMed

Hau, Pok Man; Tsao, Sai Wah

2017-11-16

The Epstein-Barr virus (EBV) is a ubiquitous virus that infects most of the human population. EBV infection is associated with multiple human cancers, including Burkitt's lymphoma, Hodgkin's lymphoma, a subset of gastric carcinomas, and almost all undifferentiated non-keratinizing nasopharyngeal carcinoma. Intensive research has shown that EBV triggers a DNA damage response (DDR) during primary infection and lytic reactivation. The EBV-encoded viral proteins have been implicated in deregulating the DDR signaling pathways. The consequences of DDR inactivation lead to genomic instability and promote cellular transformation. This review summarizes the current understanding of the relationship between EBV infection and the DDR transducers, including ATM (ataxia telangiectasia mutated), ATR (ATM and Rad3-related), and DNA-PK (DNA-dependent protein kinase), and discusses how EBV manipulates the DDR signaling pathways to complete the replication process of viral DNA during lytic reactivation.

A novel mouse xenotransplantation model of EBV-T/NK-LPD and the application of the mouse model.

PubMed

Imadome, Ken-Ichi

2013-01-01

Chronic active Epstein-Barr virus (EBV) infection (CAEBV), characterized by proliferation of EBV-infected T or NK cells, is a disease of unknown pathogenesis and requires hematopoietic stem cell transplantation for curative treatment. Here we show that intravenous injection of peripheral blood mononuclear cells (PBMCs) isolated from patients with CAEBV to NOD/Shi-scid/IL-2R γ(null) (NOG) mice leads to engraftment of EBV-infected T or NK cells. Analysis of TCR repertoire identified an identical predominant EBV-infected T-cell clone both in a patient and a mouse transplanted with his PBMCs. EBV-infected T or NK cells infiltrated to most major organs including the liver, spleen, lungs, kidneys, adrenal glands, and intestine, showing histological characteristics of CAEBV. Expression of EBNA1, LMP1, and LMP2A, but not EBNA2, in these cells indicated the latency II program of EBV gene characteristic to CAEBV. High levels of TNF-α, IFN-γ, and RANTES were detected in the peripheral blood of these mice. EBV-containing fractions of either CD8(+), γδT, or NK cell lineages failed to engraft, once they were isolated from PBMCs ; they could engraft only when CD4(+) cell fraction was transplanted in parallel. Isolated EBV-containing CD4(+) T cells, in contrast, did engraft on their own. This is the first report of an animal model of CAEBV and suggest that EBV-infected T or NK cells in CAEBV are not truly neoplastic but are dependent on CD4(+) T cells for their proliferation in vivo.

Monoclonal and anti-idiotypic anti-EBV/C3d receptor antibodies detect two binding sites, one for EBV and one for C3d on glycoprotein 140, the EBV/C3dR, expressed on human B lymphocytes.

PubMed

Barel, M; Fiandino, A; Delcayre, A X; Lyamani, F; Frade, R

1988-09-01

Glycoprotein (gp) 140, the EBV/C3dR of B lymphocytes, is a membrane site involved in human cell regulation. To analyze the specificities of the binding sites for EBV and for C3d on the gp 140 molecule, two distinct approaches were used. First, anti-EBV/C3dR mAb were prepared against highly purified EBV/C3dR. Nine anti-EBV/C3dR mAb were obtained. Four of these anti-EBV/C3dR mAb inhibited C3d binding but not EBV binding on gp 140, whereas four others exerted an inverse effect. These differences could not be due to differences in isotype, antibody concentration, affinity constant, and number of molecules bound on cell surface, as these parameters were identical for the nine used mAb. Second, polyclonal anti-idiotypic antibodies (Ab2) were prepared against F(ab)'2 fragments of polyclonal anti-EBV/C3dR (Ab1). Ab2 recognized the variable portion of Ab1 as controlled by immunoblotting experiments. Ab2, which did not react with the cell surface, inhibited Ab1 binding on Raji cells. Ab2 mimicked the EBV/C3dR by its properties to bind to particle-bound C3d and EBV, preventing their binding on Raji cell surface. C3d binding specificities contained in Ab2 were isolated by affinity chromatography on C3b/C3bi-Sepharose. These specificities, being the internal image of C3d binding site of EBV/C3dR, reacted with Ab1 and inhibited particle-bound C3d binding on Raji cells but did not react with EBV. Taken together, these data support strongly that gp 140, the EBV/C3dR, carried two distinct binding sites, one for EBV and one for C3d.

Epstein-Barr virus (EBV)–encoded small RNA is released from EBV-infected cells and activates signaling from toll-like receptor 3

PubMed Central

Iwakiri, Dai; Zhou, Li; Samanta, Mrinal; Matsumoto, Misako; Ebihara, Takashi; Seya, Tsukasa; Imai, Shosuke; Fujieda, Mikiya; Kawa, Keisei

2009-01-01

Epstein-Barr virus–encoded small RNA (EBER) is nonpolyadenylated, noncoding RNA that forms stem-loop structure by intermolecular base-pairing, giving rise to double-stranded RNA (dsRNA)–like molecules, and exists abundantly in EBV-infected cells. Here, we report that EBER induces signaling from the Toll-like receptor 3 (TLR3), which is a sensor of viral double-stranded RNA (dsRNA) and induces type I IFN and proinflammatory cytokines. A substantial amount of EBER, which was sufficient to induce signaling from TLR3, was released from EBV-infected cells, and the majority of the released EBER existed as a complex with a cellular EBER-binding protein La, suggesting that EBER was released from the cells by active secretion of La. Sera from patients with infectious mononucleosis (IM), chronic active EBV infection (CAEBV), and EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH), whose general symptoms are caused by proinflammatory cytokines contained EBER, and addition of RNA purified from the sera into culture medium induced signaling from TLR3 in EBV-transformed lymphocytes and peripheral mononuclear cells. Furthermore, DCs treated with EBER showed mature phenotype and antigen presentation capacity. These findings suggest that EBER, which is released from EBV-infected cells, is responsible for immune activation by EBV, inducing type I IFN and proinflammatory cytokines. EBER-induced activation of innate immunity would account for immunopathologic diseases caused by active EBV infection. PMID:19720839

[Systemic EBV+ T-cell lymphoproliferative disease of childhood].

PubMed

Lemaire, Anne-Sophie; Daussay, Dorothée; Bouchindhomme, Brigitte; Grardel, Nathalie; Botte, Astrid; Copin, Marie-Christine

2014-08-01

Systemic EBV+ T-cell lymphoproliferative disease of childhood is a recent entity described in the 2008 World Health Organisation tumours of haematopoietic system and lymphoid tissues as a clonal T-cell EBV+ systemic proliferation. It occurs after acute or chronic active EBV infection. We report the case of a caucasian, immunocompetent 12-year-old girl, with no particular history, who presented with hemophagocytic lymphohistiocytosis in the aftermath of an infectious mononucleosis. Main symptoms were multiple organ failure, hepatosplenomegaly and pancytopenia. Histopathology of peripheral lymph node and bone marrow revealed a T-cell, CD8+, EBV+ lymphoproliferation. An elevated viral load was detected in blood by PCR. The patient died within 3 weeks. Since most of the cases have been reported in Asia and South America, few cases still have been described in Europe. Unlike B-cell lymphoproliferation in immunocompromised individuals, T-cell EBV+ lymphoproliferation occurs in immunocompetent patients and seems to be the consequence of a proliferative disorder of EBV-infected T-cells, attributed to a cytotoxic T-cell response deficiency. These T-cell proliferations are more frequently immunoreactive for CD8 than CD4. A key feature of the diagnosis might be EBV viral load. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Epstein–Barr virus latent genes

PubMed Central

Kang, Myung-Soo; Kieff, Elliott

2015-01-01

Latent Epstein–Barr virus (EBV) infection has a substantial role in causing many human disorders. The persistence of these viral genomes in all malignant cells, yet with the expression of limited latent genes, is consistent with the notion that EBV latent genes are important for malignant cell growth. While the EBV-encoded nuclear antigen-1 (EBNA-1) and latent membrane protein-2A (LMP-2A) are critical, the EBNA-leader proteins, EBNA-2, EBNA-3A, EBNA-3C and LMP-1, are individually essential for in vitro transformation of primary B cells to lymphoblastoid cell lines. EBV-encoded RNAs and EBNA-3Bs are dispensable. In this review, the roles of EBV latent genes are summarized. PMID:25613728

Secreted Oral Epithelial Cell Membrane Vesicles Induce Epstein-Barr Virus Reactivation in Latently Infected B Cells

PubMed Central

Lin, Zhen; Swan, Kenneth; Zhang, Xin; Cao, Subing; Brett, Zoe; Drury, Stacy; Fewell, Claire; Puetter, Adriane; Wang, Xia; Ferris, MaryBeth; Sullivan, Deborah E.; Li, Li

2016-01-01

ABSTRACT In the oral epithelium, peripheral stores of Epstein-Barr virus (EBV) are transmitted from infiltrating B cells to epithelial cells. Once the virus is transmitted to epithelial cells, the highly permissive nature of this cell type for lytic replication allows virus amplification and exchange to other hosts. Since the initial transfer of EBV from B cells to epithelial cells requires transitioning of the B-cell to a state that induces virus reactivation, we hypothesized that there might be epithelium-specific signals that allow the infiltrating B cells to sense the appropriate environment to initiate reactivation and begin this exchange process. We previously found that the epithelium-specific miR-200 family of microRNAs promotes EBV lytic replication. Here we show that there are high levels of miR-200 family members in oral and tonsillar epithelia and in saliva. Analysis of cultured oral epithelial cells (OKF6) showed that they actively secrete membrane vesicles (exosomes) that are enriched with miR-200 family members. Coculturing of EBV-positive B cells with OKF6 cells induced viral reactivation. Further, treatment of EBV-positive B cells with OKF6 cell-derived membrane vesicles promoted reactivation. Using a cell system that does not naturally express miR-200 family members, we found that enforced expression of a miR-200 family member produced membrane vesicles that were able to induce the lytic cascade in EBV-positive B cells. We propose that membrane vesicles secreted by oral and tonsillar epithelial cells may serve as a tissue-specific environmental cue that initiates reactivation in B cells, promoting the transfer of virus from peripheral B-cell stores to the oral epithelium to facilitate virus amplification and exchange to other hosts. IMPORTANCE Epstein-Barr virus (EBV) is an important human pathogen that is causally associated with several lymphomas and carcinomas. The switch from latency to the lytic cycle is critical for successful host infection

HLA class I associations with EBV+ post-transplant lymphoproliferative disorder.

PubMed

Jones, Kimberley; Wockner, Leesa; Thornton, Alycia; Gottlieb, David; Ritchie, David S; Seymour, John F; Kumarasinghe, Gayathri; Gandhi, Maher K

2015-03-01

Epstein-Barr virus (EBV) is frequently associated with post-transplant lymphoproliferative disorders (EBV(+) PTLD). In these cases, impaired Epstein-Barr virus (EBV)-specific CD8(+) T-cell immunity is strongly implicated and antigen presentation within the malignant B-cell is intact. Interestingly, several studies have reported HLA class I alleles with protective or susceptibility associations. However, results are conflicting, likely influenced by methodology including inconsistent use of multiple hypothesis testing. By contrast, HLA class I associations have been repeatedly reported for classical Hodgkin Lymphoma (cHL), in which EBV is also implicated in a proportion of cases. In contrast to EBV(+) PTLD which expresses the immunodominant EBV latency III EBNA3A/B/C proteins, EBV(+) cHL is restricted to the subdominant EBNA1/LMP1/LMP2 proteins. Herein, we report a study of HLA class I associations in EBV(+) PTLD, with 263 patients with lymphoma (cHL or PTLD) evaluated. Two Australian population cohorts, n = 23,736 and n = 891 were used for comparison. Contrary to previous reports, no HLA class I associations with EBV(+) PTLD were found, whereas for cHL known HLA class I associations were confirmed, with HLA-A*02 homozygous individuals having the lowest odds of developing EBV(+) cHL. Our results suggest that HLA class I does not influence susceptibility to the viral latency III expressing lymphoma, EBV(+) PTLD. Further studies are required for definitive confirmation. Copyright © 2015. Published by Elsevier B.V.

High-throughput sequencing of TCR repertoires in multiple sclerosis reveals intrathecal enrichment of EBV-reactive CD8+ T cells.

PubMed

Lossius, Andreas; Johansen, Jorunn N; Vartdal, Frode; Robins, Harlan; Jūratė Šaltytė, Benth; Holmøy, Trygve; Olweus, Johanna

2014-11-01

Epstein-Barr virus (EBV) has long been suggested as a pathogen in multiple sclerosis (MS). Here, we used high-throughput sequencing to determine the diversity, compartmentalization, persistence, and EBV-reactivity of the T-cell receptor (TCR) repertoires in MS. TCR-β genes were sequenced in paired samples of cerebrospinal fluid (CSF) and blood from patients with MS and controls with other inflammatory neurological diseases. The TCR repertoires were highly diverse in both compartments and patient groups. Expanded T-cell clones, represented by TCR-β sequences >0.1%, were of different identity in CSF and blood of MS patients, and persisted for more than a year. Reference TCR-β libraries generated from peripheral blood T cells reactive against autologous EBV-transformed B cells were highly enriched for public EBV-specific sequences and were used to quantify EBV-reactive TCR-β sequences in CSF. TCR-β sequences of EBV-reactive CD8+ T cells, including several public EBV-specific sequences, were intrathecally enriched in MS patients only, whereas those of EBV-reactive CD4+ T cells were also enriched in CSF of controls. These data provide evidence for a clonally diverse, yet compartmentalized and persistent, intrathecal T-cell response in MS. The presented strategy links TCR sequence to intrathecal T-cell specificity, demonstrating enrichment of EBV-reactive CD8+ T cells in MS. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

K-bZIP Mediated SUMO-2/3 Specific Modification on the KSHV Genome Negatively Regulates Lytic Gene Expression and Viral Reactivation

PubMed Central

Yang, Wan-Shan; Hsu, Hung-Wei; Campbell, Mel; Cheng, Chia-Yang; Chang, Pei-Ching

2015-01-01

SUMOylation is associated with epigenetic regulation of chromatin structure and transcription. Epigenetic modifications of herpesviral genomes accompany the transcriptional switch of latent and lytic genes during the virus life cycle. Here, we report a genome-wide comparison of SUMO paralog modification on the KSHV genome. Using chromatin immunoprecipitation in conjunction with high-throughput sequencing, our study revealed highly distinct landscape changes of SUMO paralog genomic modifications associated with KSHV reactivation. A rapid and widespread deposition of SUMO-2/3, compared with SUMO-1, modification across the KSHV genome upon reactivation was observed. Interestingly, SUMO-2/3 enrichment was inversely correlated with H3K9me3 mark after reactivation, indicating that SUMO-2/3 may be responsible for regulating the expression of viral genes located in low heterochromatin regions during viral reactivation. RNA-sequencing analysis showed that the SUMO-2/3 enrichment pattern positively correlated with KSHV gene expression profiles. Activation of KSHV lytic genes located in regions with high SUMO-2/3 enrichment was enhanced by SUMO-2/3 knockdown. These findings suggest that SUMO-2/3 viral chromatin modification contributes to the diminution of viral gene expression during reactivation. Our previous study identified a SUMO-2/3-specific viral E3 ligase, K-bZIP, suggesting a potential role of this enzyme in regulating SUMO-2/3 enrichment and viral gene repression. Consistent with this prediction, higher K-bZIP binding on SUMO-2/3 enrichment region during reactivation was observed. Moreover, a K-bZIP SUMO E3 ligase dead mutant, K-bZIP-L75A, in the viral context, showed no SUMO-2/3 enrichment on viral chromatin and higher expression of viral genes located in SUMO-2/3 enriched regions during reactivation. Importantly, virus production significantly increased in both SUMO-2/3 knockdown and KSHV K-bZIP-L75A mutant cells. These results indicate that SUMO-2/3 modification

Advances in Virus-Directed Therapeutics against Epstein-Barr Virus-Associated Malignancies

PubMed Central

Ghosh, Sajal K.; Perrine, Susan P.; Faller, Douglas V.

2012-01-01

Epstein-Barr virus (EBV) is the causal agent in the etiology of Burkitt's lymphoma and nasopharyngeal carcinoma and is also associated with multiple human malignancies, including Hodgkin's and non-Hodgkin's lymphoma, and posttransplantation lymphoproliferative disease, as well as sporadic cancers of other tissues. A causal relationship of EBV to these latter malignancies remains controversial, although the episomic EBV genome in most of these cancers is clonal, suggesting infection very early in the development of the tumor and a possible role for EBV in the genesis of these diseases. Furthermore, the prognosis of these tumors is invariably poor when EBV is present, compared to their EBV-negative counterparts. The physical presence of EBV in these tumors represents a potential “tumor-specific” target for therapeutic approaches. While treatment options for other types of herpesvirus infections have evolved and improved over the last two decades, however, therapies directed at EBV have lagged. A major constraint to pharmacological intervention is the shift from lytic infection to a latent pattern of gene expression, which persists in those tumors associated with the virus. In this paper we provide a brief account of new virus-targeted therapeutic approaches against EBV-associated malignancies. PMID:22500168

An Epstein-Barr virus immediate-early gene product trans-activates gene expression from the human immunodeficiency virus long terminal repeat.

PubMed Central

Kenney, S; Kamine, J; Markovitz, D; Fenrick, R; Pagano, J

1988-01-01

Acquired immunodeficiency syndrome patients are frequently coinfected with Epstein-Barr virus (EBV). In this report, we demonstrate that an EBV immediate-early gene product, BamHI MLF1, stimulates expression of the bacterial chloramphenicol acetyltransferase (CAT) gene linked to the human immunodeficiency virus (HIV) promoter. The HIV promoter sequences necessary for trans-activation by EBV do not include the tat-responsive sequences. In addition, in contrast to the other herpesvirus trans-activators previously studied, the EBV BamHI MLF1 gene product appears to function in part by a posttranscriptional mechanism, since it increases pHIV-CAT protein activity more than it increases HIV-CAT mRNA. This ability of an EBV gene product to activate HIV gene expression may have biologic consequences in persons coinfected with both viruses. Images PMID:2830625

An Epstein-Barr virus immediate-early gene product trans-activates gene expression from the human immunodeficiency virus long terminal repeat.

PubMed

Kenney, S; Kamine, J; Markovitz, D; Fenrick, R; Pagano, J

1988-03-01

Acquired immunodeficiency syndrome patients are frequently coinfected with Epstein-Barr virus (EBV). In this report, we demonstrate that an EBV immediate-early gene product, BamHI MLF1, stimulates expression of the bacterial chloramphenicol acetyltransferase (CAT) gene linked to the human immunodeficiency virus (HIV) promoter. The HIV promoter sequences necessary for trans-activation by EBV do not include the tat-responsive sequences. In addition, in contrast to the other herpesvirus trans-activators previously studied, the EBV BamHI MLF1 gene product appears to function in part by a posttranscriptional mechanism, since it increases pHIV-CAT protein activity more than it increases HIV-CAT mRNA. This ability of an EBV gene product to activate HIV gene expression may have biologic consequences in persons coinfected with both viruses.

Epstein-Barr virus BZLF1 gene promoter variants in pediatric patients with acute infectious mononucleosis: its comparison with pediatric lymphomas.

PubMed

Lorenzetti, Mario Alejandro; Gutiérrez, Marina Inés; Altcheh, Jaime; Moscatelli, Guillermo; Moroni, Samanta; Chabay, Paola Andrea; Preciado, María Victoria

2009-11-01

Epstein-Barr virus genotypes can be distinguished by polymorphic variations in the genes encoding EBNA2, 3A, 3B, and 3C. The immediate early gene BZLF1 plays a key role in modulating the switch from latency to lytic replication and therefore enabling viral propagation. The aim of this study was to investigate and compare BZLF1 promoter sequence (Zp) variation in pediatric infectious mononucleosis (IM) and in pediatric EBV positive lymphoma biopsies. Zp was sequenced from peripheral blood mononuclear cells (PBMC) and throat swabs from 10 patients with IM at the time of diagnosis (D0) and during convalescence; and from 13 lymphoma biopsies. Zp - P and Zp - V3 variants were found in eight and one IM patients, as well as in five and six tumor biopsies, respectively. A correlation between viral genotype and Zp variant was found significant for Zp - V3 and EBV2 (P = 0.0002). One IM patient harbored two concomitant Zp variants. Regardless of anatomical compartment or stage of disease all IM patients displayed the same Zp variant along the course of the study. No new infections or adaptative selection of different variants was evidenced. A new Zp variant (Zp - V3 + 49) was described in two Hodgkin lymphomas, but not in IM. This is the first study to describe Zp variants compartmentalization in children with acute EBV infection and convalescence in a developing country; and comparing them with Zp variants in pediatric lymphomas from the same geographic area.

A Novel Persistence Associated EBV miRNA Expression Profile Is Disrupted in Neoplasia

PubMed Central

Qiu, Jin; Cosmopoulos, Katherine; Pegtel, Michiel; Hopmans, Erik; Murray, Paul; Middeldorp, Jaap; Shapiro, Michael; Thorley-Lawson, David A.

2011-01-01

We have performed the first extensive profiling of Epstein-Barr virus (EBV) miRNAs on in vivo derived normal and neoplastic infected tissues. We describe a unique pattern of viral miRNA expression by normal infected cells in vivo expressing restricted viral latency programs (germinal center: Latency II and memory B: Latency I/0). This includes the complete absence of 15 of the 34 miRNAs profiled. These consist of 12 BART miRNAs (including approximately half of Cluster 2) and 3 of the 4 BHRF1 miRNAs. All but 2 of these absent miRNAs become expressed during EBV driven growth (Latency III). Furthermore, EBV driven growth is accompanied by a 5–10 fold down regulation in the level of the BART miRNAs expressed in germinal center and memory B cells. Therefore, Latency III also expresses a unique pattern of viral miRNAs. We refer to the miRNAs that are specifically expressed in EBV driven growth as the Latency III associated miRNAs. In EBV associated tumors that employ Latency I or II (Burkitt's lymphoma, Hodgkin's disease, nasopharyngeal carcinoma and gastric carcinoma), the Latency III associated BART but not BHRF1 miRNAs are up regulated. Thus BART miRNA expression is deregulated in the EBV associated tumors. This is the first demonstration that Latency III specific genes (the Latency III associated BARTs) can be expressed in these tumors. The EBV associated tumors demonstrate very similar patterns of miRNA expression yet were readily distinguished when the expression data were analyzed either by heat-map/clustering or principal component analysis. Systematic analysis revealed that the information distinguishing the tumor types was redundant and distributed across all the miRNAs. This resembles “secret sharing” algorithms where information can be distributed among a large number of recipients in such a way that any combination of a small number of recipients is able to understand the message. Biologically, this may be a consequence of functional redundancy between

Ganetespib, an HSP90 inhibitor, kills Epstein-Barr virus (EBV)-infected B and T cells and reduces the percentage of EBV-infected cells in the blood.

PubMed

Shatzer, Amber; Ali, Mir A; Chavez, Mayra; Dowdell, Kennichi; Lee, Min-Jung; Tomita, Yusuke; El-Hariry, Iman; Trepel, Jane B; Proia, David A; Cohen, Jeffrey I

2017-04-01

HSP90 inhibitors have been shown to kill Epstein-Barr virus (EBV)-infected cells by reducing the level of EBV EBNA-1 and/or LMP1. We treated virus-infected cells with ganetespib, an HSP90 inhibitor currently being evaluated in multiple clinical trials for cancer and found that the drug killed EBV-positive B and T cells and reduced the level of both EBV EBNA-1 and LMP1. Treatment of cells with ganetespib also reduced the level of pAkt. Ganetespib delayed the onset of EBV-positive lymphomas and prolonged survival in SCID mice inoculated with one EBV-transformed B-cell line, but not another B-cell line. The former cell line showed lower levels of EBNA-1 after treatment with ganetespib in vitro. Treatment of a patient with T-cell chronic active EBV with ganetespib reduced the percentage of EBV-positive cells in the peripheral blood. These data indicate that HSP90 inhibitors may have a role in the therapy of certain EBV-associated diseases.

Persistently high Epstein-Barr virus (EBV) loads in peripheral blood lymphocytes from patients with chronic active EBV infection.

PubMed

Maeda, A; Wakiguchi, H; Yokoyama, W; Hisakawa, H; Tomoda, T; Kurashige, T

1999-04-01

Chronic active Epstein-Barr virus infection (CAEBV) is a severe illness with unusual EBV activation that persists for years, and its pathogenesis is largely unknown. After the creation of an accurate and reproducible polymerase chain reaction system to quantify EBV DNA, virus loads in peripheral blood lymphocytes (PBL) were determined in 54 children: 15 with CAEBV, 16 with infectious mononucleosis (IM), and 23 healthy children. Children with CAEBV and those with IM had high virus loads. Lower loads were detected in 47% of seropositive healthy donors. There were two distinct differences between children with CAEBV and those with IM: The former had greater viral replication (10(3)-10(7) copies/2.5x10(5) PBL) than those with IM, and viral replication declined in children with IM whereas active replication persisted for years in subjects with CAEBV. Persisting high virus loads are a possible diagnostic criterion for CAEBV. EBV loads may enable classification and prognosis of EBV infections.

Detailed kinetics of EBV-specific CD4+ and CD8+ T cells during primary EBV infection in a kidney transplant patient.

PubMed

Piriou, Erwan R W A N; van Dort, Karel; Weel, Jan F L; Bemelman, Frederike J; Gamadia, Laila E; van Oers, Marinus H J; van Baarle, Debbie

2006-04-01

The etiology of infectious mononucleosis is poorly understood and usually detected many weeks after infection. Here, we present a unique case of primary symptomatic EBV infection after kidney transplantation, in whom we analyzed both EBV-specific CD4+ and CD8+ T cells in detail from the moment of infection up to latency. We show that EBV-specific T-cell responses in peripheral blood during primary EBV infection after kidney transplantation peaked early after the appearance of viral load, but well before onset of IM symptoms, suggesting that IM in this case is not caused by high numbers of CD8+ T cells per se but may be caused by lack of homing to lymph nodes or tonsils.

Lytic and transforming functions of individual products of the adenovirus E1A gene.

PubMed Central

Moran, E; Grodzicker, T; Roberts, R J; Mathews, M B; Zerler, B

1986-01-01

To distinguish the individual roles of the 13S, 12S, and 9S adenovirus E1A gene products, we isolated the corresponding cDNA clones and recombined them into both plasmids and viruses. Only the expected E1A mRNA products were made from the corresponding 12S and 13S viruses. The 9S mRNA was detected when the 9S virus was coinfected with the 13S virus but not when either virus was infected alone. The 13S virus formed plaques equally well in 293 cells, HeLa cells, and A549 cells, a human lung oat cell carcinoma line. Plaque titers of the 12S virus were much reduced in HeLa and A549 cells compared with 293 cells, although the 12S virus is multiplicity-dependent leaky in both HeLa and A549 cells. A549 cells were significantly more permissive than HeLa cells for growth of the 12S virus. In A549 cells even at low multiplicities of infection the final yield of 12S virus eventually approached the maximum yield from 293 cells. Expression from the adenovirus early region 2 and early region 3 promoters in HeLa cells was activated in the presence of a 13S cDNA E1A region but not in the presence of a 12S E1A cDNA region. Although defective for lytic growth in HeLa cells, the 12S virus immortalized BRK cells at very high efficiency, whereas infection of these cells with 13S virus, as with wild-type E1A virus, resulted mainly in cell death. The 13S product does have an immortalization function, however, revealed in the absence of adenovirus lytic functions when a plasmid containing the E1A 13S cDNA region was transfected into BRK cells. The 9S virus failed to immortalize infected BRK cells or to interfere with focus formation when coinfected with the 12S virus. Images PMID:2936898

Telomerase Activity Impacts on Epstein-Barr Virus Infection of AGS Cells

PubMed Central

Rac, Jürgen; Haas, Florian; Schumacher, Andrina; Middeldorp, Jaap M.; Delecluse, Henri-Jacques; Speck, Roberto F.

2015-01-01

The Epstein-Barr virus (EBV) is transmitted from host-to-host via saliva and is associated with epithelial malignancies including nasopharyngeal carcinoma (NPC) and some forms of gastric carcinoma (GC). Nevertheless, EBV does not transform epithelial cells in vitro where it is rapidly lost from infected primary epithelial cells or epithelial tumor cells. Long-term infection by EBV, however, can be established in hTERT-immortalized nasopharyngeal epithelial cells. Here, we hypothesized that increased telomerase activity in epithelial cells enhances their susceptibility to infection by EBV. Using HONE-1, AGS and HEK293 cells we generated epithelial model cell lines with increased or suppressed telomerase activity by stable ectopic expression of hTERT or of a catalytically inactive, dominant negative hTERT mutant. Infection experiments with recombinant prototypic EBV (rB95.8), recombinant NPC EBV (rM81) with increased epithelial cell tropism compared to B95.8, or recombinant B95.8 EBV with BZLF1-knockout that is not able to undergo lytic replication, revealed that infection frequencies positively correlate with telomerase activity in AGS cells but also partly depend on the cellular background. AGS cells with increased telomerase activity showed increased expression mainly of latent EBV genes, suggesting that increased telomerase activity directly acts on the EBV infection of epithelial cells by facilitating latent EBV gene expression early upon virus inoculation. Thus, our results indicate that infection of epithelial cells by EBV is a very selective process involving, among others, telomerase activity and cellular background to allow for optimized host-to-host transmission via saliva. PMID:25856387

Epigenetic dysregulation of epstein-barr virus latency and development of autoimmune disease.

PubMed

Niller, Hans Helmut; Wolf, Hans; Ay, Eva; Minarovits, Janos

2011-01-01

Epstein-Barr virus (EBV) is ahumanherpesvirus thatpersists in the memory B-cells of the majority of the world population in a latent form. Primary EBV infection is asymptomatic or causes a self-limiting disease, infectious mononucleosis. Virus latency is associated with a wide variety of neoplasms whereof some occur in immune suppressed individuals. Virus production does not occur in strict latency. The expression of latent viral oncoproteins and nontranslated RNAs is under epigenetic control via DNA methylation and histone modifications that results either in a complete silencing of the EBV genome in memory B cells, or in a cell-type dependent usage of a couple of latency promoters in tumor cells, germinal center B cells and lymphoblastoid cells (LCL, transformed by EBV in vitro). Both, latent and lytic EBV proteins elicit a strong immune response. In immune suppressed and infectious mononucleosis patients, an increased viral load can be detected in the blood. Enhanced lytic replication may result in new infection- and transformation-events and thus is a risk factor both for malignant transformation and the development of autoimmune diseases. An increased viral load or a changed presentation of a subset of lytic or latent EBV proteins that cross-react with cellular antigens may trigger pathogenic processes through molecular mimicry that result in multiple sclerosis (MS), systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA).

Epstein-Barr virus infection induces aberrant TLR activation pathway and fibroblast-myofibroblast conversion in scleroderma.

PubMed

Farina, Antonella; Cirone, Mara; York, Michael; Lenna, Stefania; Padilla, Cristina; Mclaughlin, Sarah; Faggioni, Alberto; Lafyatis, Robert; Trojanowska, Maria; Farina, Giuseppina A

2014-04-01

Scleroderma (SSc) is a complex and heterogeneous connective tissue disease mainly characterized by autoimmunity, vascular damage, and fibrosis that mostly involve the skin and lungs. Epstein-Barr virus (EBV) is a lymphotropic γ-herpesvirus that has co-evolved with human species, infecting >95% of the adult population worldwide, and has been a leading candidate in triggering several autoimmune diseases. Here we show that EBV establishes infection in the majority of fibroblasts and endothelial cells in the skin of SSc patients, characterized by the expression of the EBV noncoding small RNAs (EBERs) and the increased expression of immediate-early lytic and latency mRNAs and proteins. We report that EBV is able to persistently infect human SSc fibroblasts in vitro, inducing an aberrant innate immune response in infected cells. EBV-Toll-like receptor (TLR) aberrant activation induces the expression of selected IFN-regulatory factors (IRFs), IFN-stimulated genes (ISGs), transforming growth factor-β1 (TGFβ1), and several markers of fibroblast activation, such as smooth muscle actin and Endothelin-1, and all of these genes play a key role in determining the profibrotic phenotype in SSc fibroblasts. These findings imply that EBV infection occurring in mesenchymal, endothelial, and immune cells of SSc patients may underlie the main pathological features of SSc including autoimmunity, vasculopathy, and fibrosis, and provide a unified disease mechanism represented by EBV reactivation.

Lytic Replication of Epstein-Barr Virus During Space Flight

NASA Technical Reports Server (NTRS)

Stowe, R. P.; Pierson, D. L.; Barrett, A. D. T.

1999-01-01

Reactivation of latent Epstein-Barr virus (EBV) may be an important threat to crew health during extended space missions. Cellular immunity, which is decreased during and after space flight, is responsible for controlling EBV replication in vivo. In this study, we investigated the effects of short-term space flight on latent EBV reactivation.

NK and NK-like T-cell lymphoma in extranasal sites: a comparative clinicopathological study according to site and EBV status.

PubMed

Ko, Y H; Cho, E-Y; Kim, J-E; Lee, S-S; Huh, J-R; Chang, H-K; Yang, W-I; Kim, C-W; Kim, S-W; Ree, H J

2004-05-01

To analyse the clinicopathological findings of extranasal CD56+ cytotoxic T- or NK-cell lymphomas in different organs and to compare Epstein-Barr virus (EBV)+ and EBV- lymphoma of non-blastoid cytomorphology. Fifty-one cases of cCD3+ T-cell intracellular antigen (TIA-1)+ CD56+ lymphomas of extranodal/extranasal origin were included in the study. The primary sites of the CD56+ tumours were soft tissue (n = 10), the gastrointestinal (GI) tract (n = 13), the skin (n = 15), upper aerodigestive tract excluding nasal and nasopharyngeal regions (n = 11), the testis (n = 1), and parotid gland (n = 1). TCR gene rearrangement was detected in seven of 47 cases examined (16%). EBV was positive in 39 of 51 cases (76%). The positive rate of EBV was higher in tumours of soft tissue (80%), GI tract (92%), and skin (80%), and lowest in the upper aerodigestive tract excluding the nasal and nasopharyngeal region (50%). Tumours of the soft tissue and the upper aerodigestive tract tended to present with localized disease (P = 0.002). The 2-year survival rate was lowest for tumours of the GI tract (P = 0.0256). EBV- TCR- lymphoma showed less necrosis (P = 0.0133) and a better 2-year survival rate (P = 0.0066) than EBV+ TCR- lymphoma. Patients with EBV+ TCR+ lymphomas tended to present with localized disease, more often than EBV+ TCR- lymphoma (P = 0.0186). Significant prognostic factors in all CD56+ lymphomas were the site (P = 0.0256), EBV status (P = 0.0026), necrosis with or without perforation (P = 0.0338) and the presence of pleomorphic large tumour cells (P = 0.0428). Cox's regression analysis adjusting for other pathological parameters showed EBV status to be the only independent prognostic factor (P = 0.018). Extranodal CD56+ EBV- lymphoma at extranasal sites is a clinically less aggressive malignancy and displays less necrosis than CD56+ EBV+ lymphoma. Because CD56+ EBV+ TCR+ lymphomas show similar pathological and clinical findings to CD56+ EBV+ TCR- lymphomas, nasal-type NK

Phage lytic proteins: biotechnological applications beyond clinical antimicrobials

USDA-ARS?s Scientific Manuscript database

Most bacteriophages encode two types of cell wall lytic proteins: Endolysins (lysins) and virion-associated peptidoglycan hydrolases. Both enzymes have the ability to degrade the peptidoglycan of Gram positive bacteria resulting in cell lysis when they are applied externally. Bacteriophage lytic p...

Bacteriophage lytic to Desulfovibrio aespoeensis isolated from deep groundwater.

PubMed

Eydal, Hallgerd S C; Jägevall, Sara; Hermansson, Malte; Pedersen, Karsten

2009-10-01

Viruses were earlier found to be 10-fold more abundant than prokaryotes in deep granitic groundwater at the Aspö Hard Rock Laboratory (HRL). Using a most probable number (MPN) method, 8-30 000 cells of sulphate-reducing bacteria per ml were found in groundwater from seven boreholes at the Aspö HRL. The content of lytic phages infecting the indigenous bacterium Desulfovibrio aespoeensis in Aspö groundwater was analysed using the MPN technique for phages. In four of 10 boreholes, 0.2-80 phages per ml were found at depths of 342-450 m. Isolates of lytic phages were made from five cultures. Using transmission electron microscopy, these were characterized and found to be in the Podoviridae morphology group. The isolated phages were further analysed regarding host range and were found not to infect five other species of Desulfovibrio or 10 Desulfovibrio isolates with up to 99.9% 16S rRNA gene sequence identity to D. aespoeensis. To further analyse phage-host interactions, using a direct count method, growth of the phages and their host was followed in batch cultures, and the viral burst size was calculated to be approximately 170 phages per lytic event, after a latent period of approximately 70 h. When surviving cells from infected D. aespoeensis batch cultures were inoculated into new cultures and reinfected, immunity to the phages was found. The parasite-prey system found implies that viruses are important for microbial ecosystem diversity and activity, and for microbial numbers in deep subsurface groundwater.

Functional requirements for bacteriophage growth: gene essentiality and expression in mycobacteriophage Giles.

PubMed

Dedrick, Rebekah M; Marinelli, Laura J; Newton, Gerald L; Pogliano, Kit; Pogliano, Joseph; Hatfull, Graham F

2013-05-01

Bacteriophages represent a majority of all life forms, and the vast, dynamic population with early origins is reflected in their enormous genetic diversity. A large number of bacteriophage genomes have been sequenced. They are replete with novel genes without known relatives. We know little about their functions, which genes are required for lytic growth, and how they are expressed. Furthermore, the diversity is such that even genes with required functions - such as virion proteins and repressors - cannot always be recognized. Here we describe a functional genomic dissection of mycobacteriophage Giles, in which the virion proteins are identified, genes required for lytic growth are determined, the repressor is identified, and the transcription patterns determined. We find that although all of the predicted phage genes are expressed either in lysogeny or in lytic growth, 45% of the predicted genes are non-essential for lytic growth. We also describe genes required for DNA replication, show that recombination is required for lytic growth, and that Giles encodes a novel repressor. RNAseq analysis reveals abundant expression of a small non-coding RNA in a lysogen and in late lytic growth, although it is non-essential for lytic growth and does not alter lysogeny. © 2013 Blackwell Publishing Ltd.

Epstein-Barr virus immediate-early gene product trans-activates gene expression from the human immunodeficiency virus long terminal repeat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kenney, S.; Kamine, J.; Markovitz, D.

Acquired immunodeficiency syndrome patients are frequently coinfected with Epstein-Barr virus (EBV). In this report, the authors demonstrate that an EBV immediate-early gene product, BamHI MLF1, stimulates expression of the bacterial chloramphenicol acetyltransferase (CAT) gene linked to the human immunodeficiency virus (HIV) promoter. The HIV promoter sequences necessary for trans-activation by EBV do not include the tat-responsive sequences. In addition, in contrast to the other herpesvirus trans-activators previously studied, the EBV BamHI MLF1 gene product appears to function in part by a posttranscriptional mechanism, since it increases pHIV-CAT protein activity more than it increases HIV-CAT mRNA. This ability of an EBVmore » gene product to activate HIV gene expression may have biologic consequences in persons coinfected with both viruses.« less

An Animal Model for Human EBV-Associated Hemophagocytic Syndrome

PubMed Central

Hayashi, Kazuhiko; Ohara, Nobuya; Teramoto, Norihiro; Onoda, Sachiyo; Chen, Hong-Li; Oka, Takashi; Kondo, Eisaku; Yoshino, Tadashi; Takahashi, Kiyoshi; Yates, John; Akagi, Tadaatsu

2001-01-01

Epstein-Barr virus-associated hemophagocytic syndrome (EBV-AHS) is often associated with fatal infectious mononucleosis. However, the animal model for EBV-AHS has not been developed. We reported the first animal model for EBV-AHS using rabbits infected with EBV-related herpesvirus of baboon (HVP). Eleven of 13 (85%) rabbits inoculated intravenously with HVP-producing cells developed fatal lymphoproliferative disorders (LPD) between 22 and 105 days after inoculation. LPD was also accompanied by hemophagocytic syndrome (HPS) in nine of these 11 rabbits. The peroral spray of cell-free HVP induced the virus infection with increased anti-EBV-viral capsid antigen-IgG titers in three of five rabbits, and two of these three infected rabbits died of LPD with HPS. Autopsy revealed hepatosplenomegaly and swollen lymph nodes. Atypical lymphoid T cells expressing EBV-encoded small RNA-1 infiltrated diffusely in many organs, frequently involving the lymph nodes, spleen, and liver. Hemophagocytic histiocytosis was observed in the lymph nodes, spleen, bone marrow, and thymus. HVP-DNA was detected in the tissues and peripheral blood from the infected rabbits by polymerase chain reaction or Southern blot analysis. Reverse transcriptase-polymerase chain reaction revealed both HVP-EBNA1 and HVP-EBNA2 transcripts, suggesting latency type III infection. These data indicate that the high rate of rabbit LPD with HPS induction is caused by HVP. This system is useful for studying the pathogenesis, prevention, and treatment of human EBV-AHS. PMID:11290571

Novel Mouse Xenograft Models Reveal a Critical Role of CD4+ T Cells in the Proliferation of EBV-Infected T and NK Cells

PubMed Central

Arai, Ayako; Nakazawa, Atsuko; Kawano, Fuyuko; Ichikawa, Sayumi; Shimizu, Norio; Yamamoto, Naoki; Morio, Tomohiro; Ohga, Shouichi; Nakamura, Hiroyuki; Ito, Mamoru; Miura, Osamu; Komano, Jun; Fujiwara, Shigeyoshi

2011-01-01

Epstein-Barr virus (EBV), a ubiquitous B-lymphotropic herpesvirus, ectopically infects T or NK cells to cause severe diseases of unknown pathogenesis, including chronic active EBV infection (CAEBV) and EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH). We developed xenograft models of CAEBV and EBV-HLH by transplanting patients' PBMC to immunodeficient mice of the NOD/Shi-scid/IL-2Rγnull strain. In these models, EBV-infected T, NK, or B cells proliferated systemically and reproduced histological characteristics of the two diseases. Analysis of the TCR repertoire expression revealed that identical predominant EBV-infected T-cell clones proliferated in patients and corresponding mice transplanted with their PBMC. Expression of the EBV nuclear antigen 1 (EBNA1), the latent membrane protein 1 (LMP1), and LMP2, but not EBNA2, in the engrafted cells is consistent with the latency II program of EBV gene expression known in CAEBV. High levels of human cytokines, including IL-8, IFN-γ, and RANTES, were detected in the peripheral blood of the model mice, mirroring hypercytokinemia characteristic to both CAEBV and EBV-HLH. Transplantation of individual immunophenotypic subsets isolated from patients' PBMC as well as that of various combinations of these subsets revealed a critical role of CD4+ T cells in the engraftment of EBV-infected T and NK cells. In accordance with this finding, in vivo depletion of CD4+ T cells by the administration of the OKT4 antibody following transplantation of PBMC prevented the engraftment of EBV-infected T and NK cells. This is the first report of animal models of CAEBV and EBV-HLH that are expected to be useful tools in the development of novel therapeutic strategies for the treatment of the diseases. PMID:22028658

Novel mouse xenograft models reveal a critical role of CD4+ T cells in the proliferation of EBV-infected T and NK cells.

PubMed

Imadome, Ken-ichi; Yajima, Misako; Arai, Ayako; Nakazawa, Atsuko; Kawano, Fuyuko; Ichikawa, Sayumi; Shimizu, Norio; Yamamoto, Naoki; Morio, Tomohiro; Ohga, Shouichi; Nakamura, Hiroyuki; Ito, Mamoru; Miura, Osamu; Komano, Jun; Fujiwara, Shigeyoshi

2011-10-01

Epstein-Barr virus (EBV), a ubiquitous B-lymphotropic herpesvirus, ectopically infects T or NK cells to cause severe diseases of unknown pathogenesis, including chronic active EBV infection (CAEBV) and EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH). We developed xenograft models of CAEBV and EBV-HLH by transplanting patients' PBMC to immunodeficient mice of the NOD/Shi-scid/IL-2Rγ(null) strain. In these models, EBV-infected T, NK, or B cells proliferated systemically and reproduced histological characteristics of the two diseases. Analysis of the TCR repertoire expression revealed that identical predominant EBV-infected T-cell clones proliferated in patients and corresponding mice transplanted with their PBMC. Expression of the EBV nuclear antigen 1 (EBNA1), the latent membrane protein 1 (LMP1), and LMP2, but not EBNA2, in the engrafted cells is consistent with the latency II program of EBV gene expression known in CAEBV. High levels of human cytokines, including IL-8, IFN-γ, and RANTES, were detected in the peripheral blood of the model mice, mirroring hypercytokinemia characteristic to both CAEBV and EBV-HLH. Transplantation of individual immunophenotypic subsets isolated from patients' PBMC as well as that of various combinations of these subsets revealed a critical role of CD4+ T cells in the engraftment of EBV-infected T and NK cells. In accordance with this finding, in vivo depletion of CD4+ T cells by the administration of the OKT4 antibody following transplantation of PBMC prevented the engraftment of EBV-infected T and NK cells. This is the first report of animal models of CAEBV and EBV-HLH that are expected to be useful tools in the development of novel therapeutic strategies for the treatment of the diseases.

An antisense RNA in a lytic cyanophage links psbA to a gene encoding a homing endonuclease.

PubMed

Millard, Andrew D; Gierga, Gregor; Clokie, Martha R J; Evans, David J; Hess, Wolfgang R; Scanlan, David J

2010-09-01

Cyanophage genomes frequently possess the psbA gene, encoding the D1 polypeptide of photosystem II. This protein is believed to maintain host photosynthetic capacity during infection and enhance phage fitness under high-light conditions. Although the first documented cyanophage-encoded psbA gene contained a group I intron, this feature has not been widely reported since, despite a plethora of new sequences becoming available. In this study, we show that in cyanophage S-PM2, this intron is spliced during the entire infection cycle. Furthermore, we report the widespread occurrence of psbA introns in marine metagenomic libraries, and with psbA often adjacent to a homing endonuclease (HE). Bioinformatic analysis of the intergenic region between psbA and the adjacent HE gene F-CphI in S-PM2 showed the presence of an antisense RNA (asRNA) connecting these two separate genetic elements. The asRNA is co-regulated with psbA and F-CphI, suggesting its involvement with their expression. Analysis of scaffolds from global ocean survey datasets shows this asRNA to be commonly associated with the 3' end of cyanophage psbA genes, implying that this potential mechanism of regulating marine 'viral' photosynthesis is evolutionarily conserved. Although antisense transcription is commonly found in eukaryotic and increasingly also in prokaryotic organisms, there has been no indication for asRNAs in lytic phages so far. We propose that this asRNA also provides a means of preventing the formation of mobile group I introns within cyanophage psbA genes.

Transcriptional Downregulation of ORF50/Rta by Methotrexate Inhibits the Switch of Kaposi's Sarcoma-Associated Herpesvirus/Human Herpesvirus 8 from Latency to Lytic Replication

PubMed Central

Curreli, Francesca; Cerimele, Francesca; Muralidhar, Sumitra; Rosenthal, Leonard J.; Cesarman, Ethel; Friedman-Kien, Alvin E.; Flore, Ornella

2002-01-01

Kaposi's sarcoma-associated herpesvirus (KSHV) encodes a cellular dihydrofolate reductase (DHFR) homologue. Methotrexate (MTX), a potent anti-inflammatory agent, inhibits cellular DHFR activity. We investigated the effect of noncytotoxic doses of MTX on latency and lytic KSHV replication in two KSHV-infected primary effusion lymphoma cell lines (BC-3 and BC-1) and in MTX-resistant BC-3 cells (MTX-R-BC-3 cells). Treatment with MTX completely prevented tetradecanoyl phorbol acetate-induced viral DNA replication and strongly decreased viral lytic transcript levels, even in MTX-resistant cells. However, the same treatment had no effect on transcription of cellular genes and KSHV latent genes. One of the lytic transcripts inhibited by MTX, ORF50/Rta (open reading frame), is an immediate-early gene encoding a replication-transcription activator required for expression of other viral lytic genes. Therefore, transcription of genes downstream of ORF50/Rta was inhibited, including those encoding the viral G-protein-coupled receptor (GPCR), viral interleukin-6, and K12/kaposin, which have been shown to be transforming in vitro and oncogenic in mice. Resistance to MTX has been documented in cultured cells and also in patients treated with this drug. However, MTX showed an inhibitory activity even in MTX-R-BC-3 cells. Two currently available antiherpesvirus drugs, cidofovir and foscarnet, had no effect on the transcription of these viral oncogenes and ORF50/Rta. MTX is the first example of a compound shown to downregulate the expression of ORF50/Rta and therefore prevent viral transforming gene transcription. Given that the expression of these genes may be important for tumor development, MTX could play a role in the future management of KSHV-associated malignancies. PMID:11967335

Characterization of the expanded T cell population in infectious mononucleosis: apoptosis, expression of apoptosis-related genes, and Epstein–Barr virus (EBV) status

PubMed Central

Verbeke, C S; Wenthe, U; Bergler, W F; Zentgraf, H

2000-01-01

Infectious mononucleosis (IM), a manifestation of primary infection with EBV, is characterized by a massive expansion of the T cell population. In this study we examined this expanded T cell population regarding its EBV status, its proliferative and apoptotic activity, and its expression of apoptosis-related genes. Whereas previous studies were performed on ex vivo cultures or on peripheral blood, our investigations included in vivo analysis of IM tonsillectomy specimens (14 cases) by in situ hybridization for viral RNA (EBERs) combined with immunohistochemistry (IHC; CD3, CD45RO, CD20, CD79a, Ki-67, Bcl-2, Bax, Fas, FasL) and the TUNEL method. Of the EBER+ cells 50–70% showed expression of the B cell markers CD20/CD79a. The remainder of the EBER+ cells expressed neither B nor T cell antigens. No co-expression of EBERs and T cell antigens was detected in any of the specimens. In accordance with a high rate of apoptosis (up to 2·37%) within the expanded T cell population, Bcl-2 expression was drastically reduced and FasL expression remarkably increased. The levels of Bax and Fas expression showed no or moderate up-regulation. In conclusion, the massive expansion of IM T cells is not caused by EBV infection of these cells but merely represents an intense immune reaction. Through altered expression of Bcl-2/Bax and Fas/FasL, the activated T cells are subject to enhanced apoptosis while residing within the lymphoid tissue, which eventually allows the efficient silencing of this potentially damaging T cell response. PMID:10792379

Clonal expansion of Epstein-Barr virus (EBV)-infected γδ T cells in patients with chronic active EBV disease and hydroa vacciniforme-like eruptions.

PubMed

Wada, Taizo; Toga, Akiko; Sakakibara, Yasuhisa; Toma, Tomoko; Hasegawa, Minoru; Takehara, Kazuhiko; Shigemura, Tomonari; Agematsu, Kazunaga; Yachie, Akihiro

2012-10-01

Chronic active Epstein-Barr virus (EBV) disease (CAEBV) is a systemic EBV-positive lymphoproliferative disorder characterized by fever, lymphadenopathy, and splenomegaly. Patients with CAEBV may present with cutaneous symptoms, including hypersensitivity to mosquito bites and hydroa vacciniforme (HV)-like eruptions. HV is a rare photodermatosis characterized by vesicles and crust formation after exposure to sunlight, with onset in childhood, and is associated with latent EBV infection. While γδ T cells have recently been demonstrated to be the major EBV-infected cell population in HV, the immunophenotypic features of EBV-infected γδ T cells in CAEBV with HV-like eruptions or HV remain largely undetermined. We describe three patients with CAEBV whose γδ T cells were found to be the major cellular target of EBV. HV-like eruptions were observed in two of these patients. A clonally expanded subpopulation of γδ T cells that were highly activated and T cell receptor Vγ9- and Vδ2-positive cells was demonstrated in all patients. We also show that the clonally expanded γδ T cells infiltrated into the HV-like eruptions in one patient from whom skin biopsy specimens were available. These results suggest the pathogenic roles of clonally expanded γδ T cells infected by EBV in patients with CAEBV and HV-like eruptions.

Epstein-Barr virus infection and nasopharyngeal carcinoma.

PubMed

Tsao, Sai Wah; Tsang, Chi Man; Lo, Kwok Wai

2017-10-19

Epstein-Barr virus (EBV) is associated with multiple types of human cancer, including lymphoid and epithelial cancers. The closest association with EBV infection is seen in undifferentiated nasopharyngeal carcinoma (NPC), which is endemic in the southern Chinese population. A strong association between NPC risk and the HLA locus at chromosome 6p has been identified, indicating a link between the presentation of EBV antigens to host immune cells and NPC risk. EBV infection in NPC is clonal in origin, strongly suggesting that NPC develops from the clonal expansion of a single EBV-infected cell. In epithelial cells, the default program of EBV infection is lytic replication. However, latent infection is the predominant mode of EBV infection in NPC. The establishment of latent EBV infection in pre-invasive nasopharyngeal epithelium is believed to be an early stage of NPC pathogenesis. Recent genomic study of NPC has identified multiple somatic mutations in the upstream negative regulators of NF-κB signalling. Dysregulated NF-κB signalling may contribute to the establishment of latent EBV infection in NPC. Stable EBV infection and the expression of latent EBV genes are postulated to drive the transformation of pre-invasive nasopharyngeal epithelial cells to cancer cells through multiple pathways.This article is part of the themed issue 'Human oncogenic viruses'. © 2017 The Author(s).

Racial/ethnic variation in EBV-positive classical Hodgkin lymphoma in California populations

PubMed Central

Glaser, Sally L.; Gulley, Margaret L.; Clarke, Christina A.; Keegan, Theresa H.; Chang, Ellen T.; Shema, Sarah J.; Craig, Fiona E.; DiGiuseppe, Joseph A.; Dorfman, Ronald F.; Mann, Risa B.; Anton-Culver, Hoda; Ambinder, Richard F.

2009-01-01

Epstein-Barr virus (EBV) is detected in the tumor cells of some but not all Hodgkin lymphoma (HL) patients, and evidence indicates that EBV-positive and –negative HL are distinct entities. Racial/ethnic variation in EBV-positive HL in international comparisons suggests etiologic roles for environmental and genetic factors, but these studies used clinical series and evaluated EBV presence by differing protocols. Therefore, we evaluated EBV presence in the tumors of a large (n=1,032), racially and sociodemographically diverse series of California incident classical HL cases with uniform pathology re-review and EBV detection methods. Tumor EBV-positivity was associated with Hispanic and Asian/Pacific Islander (API) but not black race/ethnicity, irrespective of demographic and clinical factors. Complex race-specific associations were observed between EBV-positive HL and age, sex, histology, stage, neighborhood socioeconomic status (SES), and birth place. In Hispanics, EBV-positive HL was associated not only with young and older age, male sex, and mixed cellularity histology, but also with foreign birth and lower SES in females, suggesting immune function responses to correlates of early childhood experience and later environmental exposures, respectively, as well as of pregnancy. For APIs, a lack of association with birth place may reflect the higher SES of API than Hispanic immigrants. In blacks, EBV-positive HL was associated with later-stage disease, consistent with racial/ethnic variation in certain cytokine polymorphisms. The racial/ethnic variation in our findings suggests that EBV-positive HL results from an intricate interplay of early- and later-life environmental, hormonal, and genetic factors leading to depressed immune function and poorly controlled EBV infection. PMID:18646185

Cooperative action in eukaryotic gene regulation: Physical properties of a viral example

NASA Astrophysics Data System (ADS)

Werner, Maria; Zhu, Lizhe; Aurell, Erik

2007-12-01

The Epstein-Barr virus (EBV) infects more than 90% of the human population, and causes glandular fever as well as several more serious diseases. It is a tumor virus, and has been widely studied as a model system for cell transformation in humans. A central feature of the EBV life cycle is its ability to persist in human B cells in different latency states, denoted latency I, II, and III. In latency III the host cell is driven to cell proliferation and hence expansion of the viral population without entering the lytic pathway, while the latency I state is almost completely dormant. We here study the effective cooperativity of the viral C promoter, active in latency III EBV cell lines. We show that the unusually large number of binding sites of two competing transcription factors, one viral and one from the host, serves to make the switch sharper (higher Hill coefficient), either by cooperative binding between molecules of the same species when they bind, or by competition between the two species if there is sufficient steric hindrance.

Nominal dysphasia and euphoria caused by EBV encephalitis

PubMed Central

Carman, Kursat Bora; Yakut, Ayten; Ekici, Arzu; Isikay, Sedat

2013-01-01

Encephalitis is an uncommon neurological complication of Ebstein-Barr virus (EBV) infection and usually presents with confusion, decreased level of consciousness, fever, epileptic seizure, emotional instability and chorea. We present a patient with EBV encephalitis, characterised by nominal dysphasia, euphoria and personality changes. PMID:23307455

Lytic agents, cell permeability, and monolayer penetrability.

PubMed

Salton, M R

1968-07-01

Cell lysis induced by lytic agents is the terminal phase of a series of events leading to membrane disorganization and breadkdown with the release of cellular macromolecules. Permeability changes following exposure to lytic systems may range from selective effects on ion fluxes to gross membrane damage and cell leakage. Lysis can be conceived as an interfacial phenomenon, and the action of surface-active agents on erythrocytes has provided a model in which to investigate relationships between hemolysis and chemical structure, ionic charge, surface tension lowering, and ability to penetrate monolayers of membrane lipid components. Evidence suggests that lysis follows the attainment of surface pressures exceeding a "critical collapse" level and could involve membrane cholesterol or phospholipid. Similarities of chemical composition of membranes from various cell types could account for lytic responses observed on interaction with surface-active agents. Cell membranes usually contain about 20-30 % lipid and 50-75 % protein. One or two major phospholipids are present in all cell membranes, but sterols are not detectable in bacterial membranes other than those of the Mycoplasma group. The rigid cell wall in bacteria has an important bearing on their response to treatment with lytic agents. Removal of the wall renders the protoplast membrane sensitive to rapid lysis with surfactants. Isolated membranes of erythrocytes and bacteria are rapidly dissociated by surface-active agents. Products of dissociation of bacterial membranes have uniform behavior in the ultracentrifuge (sedimentation coefficients 2-3S). Dissociation of membrane proteins from lipids and the isolation and characterization of these proteins will provide a basis for investigating the specificity of interaction of lytic agents with biomembranes.

Impaired Cytokine Responses to Epstein-Barr Virus Antigens in Systemic Lupus Erythematosus Patients

PubMed Central

Draborg, Anette Holck; Sandhu, Noreen; Larsen, Nanna; Lisander Larsen, Janni; Jacobsen, Søren; Houen, Gunnar

2016-01-01

We analyzed cytokine responses against latent and lytic Epstein-Barr virus (EBV) antigens in systemic lupus erythematosus (SLE) patients and healthy controls (HCs) to obtain an overview of the distinctive immune regulatory response in SLE patients and to expand the previously determined impaired EBV-directed T-cell response. The concentrations of 14 cytokines (IL2, IL4, IL5, IL6, IL10, IL12, IL17, IL18, IL1β, IFNγ, TNFα, TNFβ, TGFβ, and GM-CSF) were quantified upon stimulation of whole blood with latent state antigen EBNA1, lytic cycle antigen EBV-EA/D, and the superantigen SEB. To avoid results affected by lack of lymphocytes, we focused on SLE patients with normal levels. Decreased induction of IL12, IFNγ, IL17, and IL6 upon EBNA1 stimulation and that of IFNγ, IL6, TNFβ, IL1β, and GM-CSF upon EBV-EA/D stimulation were detected in SLE patients compared to HCs. IFNγ responses, especially, were shown to be reduced. Induction of several cytokines was furthermore impaired in SLE patients upon SEB stimulation, but no difference was observed in basic levels. Results substantiate the previously proposed impaired regulation of the immune response against latent and lytic cycle EBV infection in SLE patients without lymphopenia. Furthermore, results indicate general dysfunction of leukocytes and their cytokine regulations in SLE patients. PMID:27110576

Dynamics of Epstein-Barr virus DNA levels in serum during EBV-associated disease.

PubMed

Berger, C; Day, P; Meier, G; Zingg, W; Bossart, W; Nadal, D

2001-08-01

A real-time polymerase chain reaction assay for quantitation of Epstein-Barr virus (EBV) DNA in serum was developed. This assay detected EBV DNA in 24 (89%) of 27 sera from patients with infectious mononucleosis, but only in 9 (18%) of 51 sera from EBV carriers (P < 0.001) and in none of the sera from 32 EBV-seronegative individuals. EBV DNA levels were higher in sera from infectious mononucleosis (median 8,000, range 1833-150,069 copies/ml) than from carriers (median < 2, range < 2-2980; P < 0.001). In sera of 36 children with infectious mononucleosis followed prospectively, EBV DNA levels correlated inversely with the duration of symptoms. Among 18 children with tumors including Hodgkin's disease (n = 7), non-Hodgkin's lymphoma (n = 6), Burkitt's lymphoma (n = 1), lymphoproliferative disorder (n = 4), and osteosarcoma (n = 1), EBV DNA was detected in serum from those 9 (100%) expressing EBV in the tumor (Hodgkin's disease, 3; non-Hodgkin's lymphoma, 2; lymphoproliferative disorder, 4), the levels peaking at diagnosis and correlating with disease activity. Quantitation of EBV DNA in serum may offer a simple means of monitoring patients at risk of EBV-associated lymphoproliferation. Copyright 2001 Wiley-Liss, Inc.

Studies of EBV-lymphoid cell interactions in two patients with the X-linked lymphoproliferative syndrome: normal EBV-specific HLA-restricted cytotoxicity.

PubMed

Rousset, F; Souillet, G; Roncarolo, M G; Lamelin, J P

1986-02-01

Two X-linked lymphoproliferative syndrome (XLP) patients with the hypogammaglobulinemia phenotype were investigated at a time remote from their primary infection with the Epstein-Barr virus (EBV). The lymphoblastoid cell lines derived from these patients expressed the phenotypic markers characteristic of normal mature B lymphocytes and produced normal levels of immunoglobulins (Ig). These observations imply that at least some of their B cells are phenotypically normal. The natural killer (NK) activity of the two patients was low. In one patient, activated lymphocyte killer (ALK) activity was inefficient. These two XLP patients expressed a normal EBV-specific, HLA-restricted cytotoxic activity. It thus appears, from the present findings and those in cases published previously (6/11 patients expressing normal EBV-specific cytotoxic activity), that the notion of poor specific T cell memory for EBV may not be as pivotal ass suggested or, alternatively, that this defect may not be common in hypogammaglobulinemic survivors.

Differences between T cell-type and natural killer cell-type chronic active Epstein-Barr virus infection.

PubMed

Kimura, Hiroshi; Hoshino, Yo; Hara, Shinya; Sugaya, Naomi; Kawada, Jun-Ichi; Shibata, Yukiko; Kojima, Seiji; Nagasaka, Tetsuro; Kuzushima, Kiyotaka; Morishima, Tsuneo

2005-02-15

Infections of T cells and natural killer (NK) cells play a central role in the pathogenesis of chronic active Epstein-Barr virus (CAEBV) infection. To characterize the virologic and cytokine profiles of T cell-type and NK cell-type infection, 39 patients with CAEBV infection were analyzed. Patients with T cell-type infection had higher titers of immunoglobulin G against early and late EBV antigens, suggesting lytic cycle infection. However, the pattern of EBV gene expression was latency type II; BZLF1, which is a hallmark of lytic cycle infection, could not be detected in any patients, regardless of infection type. Patients with CAEBV infection had high concentrations of proinflammatory, T helper cell type 1, and anti-inflammatory cytokines. The cytokine profile in patients with NK cell-type infection was similar to that in patients with T cell-type infection, but the concentration of IL-13 was high in patients with NK cell-type infection. These findings should help to clarify the pathogenesis of CAEBV infection and facilitate the development of more-effective treatments.

Non-canonical WNT6/WNT10A signal factor expression in EBV+ post-transplant smooth muscle tumors.

PubMed

Teiken, Kristin; Kuehnel, Mark; Rehkaemper, Jan; Kreipe, Hans; Laenger, Florian; Hussein, Kais; Jonigk, Danny

2018-01-01

Post-transplant smooth muscle tumors (PTSMTs) are rare mesenchymal neoplasms which occur after solid organ or haematopoietic stem cell transplantation. PTSMT typically consist of Epstein-Barr-virus (EBV)+ smooth muscle-like cells and show an intermediate malignancy. Their main occurrences are visceral organs, especially the liver, but intracranial appearances are described and associated with a poor prognosis. EBV drives the growth of PTSMT; however, the underlying molecular mechanisms still remain unclear. Gene expression analysis of a set of morphologically similar tumors (leiomyomas, leiomyosarcomas, angioleiomyomas and endothelial haemangiomas) from patients without immunosuppression or EBV-association was performed. Our findings indicate that PTSMT's growth is driven by two factors of the wingless-type protein family: WNT6 and WNT10A. We are first to report that in PTSMTs, a non-canonical activation of WNT, independent of beta-catenin, drives tumor cell proliferation via MTOR/AKT1, MYC and Cyclin D2.

Atypical prediagnosis Epstein-Barr virus serology restricted to EBV-positive Hodgkin lymphoma

PubMed Central

Chang, Ellen T.; Ambinder, Richard F.; Lennette, Evelyne T.; Rubertone, Mark V.; Mann, Risa B.; Borowitz, Michael; Weir, Edward G.; Abbondanzo, Susan L.; Mueller, Nancy E.

2012-01-01

An altered anti–Epstein-Barr virus (EBV) serologic profile preceding diagnosis is associated with an increased risk of Hodgkin lymphoma. It is unknown whether this atypical pattern predicts Hodgkin lymphoma risk further subdivided by determination of EBV in tumor cells. A nested case-control study of 128 incident Hodgkin lymphoma cases and 368 matched controls from active-duty military personnel with archived serum in the US Department of Defense Serum Repository was conducted to determine whether a panel of anti-EBV antibody titers differed in EBV+ and EBV− Hodgkin lymphoma. Among 40 EBV+ Hodgkin lymphoma cases and matched controls, statistically significant increased risks were associated with elevated anti-EBV VCA IgG antibody titers (relative risk = 3.1; 95% confidence interval [CI], 1.1-8.7), and an anti–EBNA-1/anti–EBNA-2 antibody ratio ≤ 1.0 versus > 1.0 (relative risk = 4.7; 95% CI, 1.6-13.8). In contrast, no significant associations were found among 88 EBV− Hodgkin lymphoma cases relative to their matched controls. In case-case analysis, EBV+ disease was significantly associated with a low anti–EBNA-1/anti–EBNA-2 antibody ratio. This distinc-tive serologic response to EBV latent antigens, indicative of immune dysfunction in other clinical settings, is associated with an increased risk of developing EBV+ but not EBV− Hodgkin lymphoma. PMID:22972983

Prognostic role of tumour-associated macrophages and regulatory T cells in EBV-positive and EBV-negative nasopharyngeal carcinoma.

PubMed

Ooft, Marc L; van Ipenburg, Jolique A; Sanders, Maxime E; Kranendonk, Mariette; Hofland, Ingrid; de Bree, Remco; Koljenović, Senada; Willems, Stefan M

2018-03-01

Tumour-associated macrophages (TAMs) and regulatory T cells (Tregs) form a special niche supporting tumour progression, and both correlate with worse survival in head and neck cancers. However, the prognostic role of TAM and Tregs in nasopharyngeal carcinoma (NPC) is still unknown. Therefore, we determined differences in TAMs and Tregs in different NPC subtypes, and their prognostic significance. Tissue of 91 NPCs was assessed for TAMs and Tregs by determination of CD68, CD163, CD206 and FOXP3 expression in the tumour microenvironment. Clinicopathological correlations were assessed using Pearson X 2 test, Fisher's exact test, analysis of variance and Mann-Whitney U test. Survival was analysed using Kaplan-Meier curves and Cox regression. CD68 and FOXP3 counts were higher in Epstein-Barr virus (EBV)-positive NPC, while CD68-/FOXP3-, CD163+/FOXP3- and CD206+/FOXP3- infiltrates were more common in EBV-negative NPC. In the whole NPC group, CD68-/FOXP3- correlated with worse overall survival (OS), and after multivariate analysis high FOXP3 count showed better OS (HR 0.352, 95% CI 0.128 to 0.968). No difference in M2 counts existed between EBV-positive and negative NPC. FOXP3, a Treg marker, seems to be an independent prognostic factor for better OS in the whole NPC group. Therefore, immune-based therapies targeting Tregs should be carefully evaluated. M2 spectrum macrophages are probably more prominent in EBV-negative NPC with also functional differences compared with EBV-positive NPC. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Reduced response to Epstein–Barr virus antigens by T-cells in systemic lupus erythematosus patients

PubMed Central

Draborg, Anette Holck; Jacobsen, Søren; Westergaard, Marie; Mortensen, Shila; Larsen, Janni Lisander; Houen, Gunnar; Duus, Karen

2014-01-01

Objective Epstein–Barr virus (EBV) has for long been associated with systemic lupus erythematosus (SLE). In this study, we investigated the levels of latent and lytic antigen EBV-specific T-cells and antibodies in SLE patients. Methods T cells were analyzed by flow cytometry and antibodies were analyzed by enzyme-linked immunosorbent assay. Results SLE patients showed a significantly reduced number of activated (CD69) T-cells upon ex vivo stimulation with EBV nuclear antigen (EBNA) 1 or EBV early antigen diffuse (EBV-EA/D) in whole blood samples compared with healthy controls. Also, a reduced number of T-cells from SLE patients were found to produce interferon-γ upon stimulation with these antigens. Importantly, responses to a superantigen were normal in SLE patients. Compared with healthy controls, SLE patients had fewer EBV-specific T-cells but higher titres of antibodies against EBV. Furthermore, an inverse correlation was revealed between the number of lytic antigen EBV-specific T-cells and disease activity of the SLE patients, with high-activity SLE patients having fewer T-cells than low-activity SLE patients. Conclusions These results indicate a limited or a defective EBV-specific T-cell response in SLE patients, which may suggest poor control of EBV infection in SLE with an immune reaction shift towards a humoral response in an attempt to control viral reactivation. A role for decreased control of EBV as a contributing agent in the development or exacerbation of SLE is proposed. PMID:25396062

The Biology and Clinical Utility of EBV Monitoring in Blood.

PubMed

Kanakry, Jennifer; Ambinder, Richard

2015-01-01

Epstein-Barr virus (EBV) DNA in blood can be quantified in peripheral blood mononuclear cells, in circulating cell-free (CCF) DNA specimens, or in whole blood. CCF viral DNA may be actively released or extruded from viable cells, packaged in virions or passively shed from cells during apoptosis or necrosis. In infectious mononucleosis, viral DNA is detected in each of these kinds of specimens, although it is only transiently detected in CCF specimens. In nasopharyngeal carcinoma, CCF EBV DNA is an established tumor marker. In EBV-associated Hodgkin lymphoma and in EBV-associated extranodal NK-/T-cell lymphoma, there is growing evidence for the utility of CCF DNA as a tumor marker.

Animal in vivo models of EBV-associated lymphoproliferative diseases: special references to rabbit models.

PubMed

Hayashi, K; Teramoto, N; Akagi, T

2002-10-01

Animal models of human EBV-associated diseases are essential to elucidate the pathogenesis of EBV-associated diseases. Here we review those previous models using EBV or EBV-like herpesviruses and describe the details on our two newly-developed rabbit models of lymphoproliferative diseases (LPD) induced by simian EBV-like viruses. The first is Cynomolgus-EBV-induced T-cell lymphomas in rabbits inoculated intravenously (77-90%) and orally (82-89%) during 2-5 months. EBV-DNA was detected in peripheral blood by PCR from 2 days after oral inoculation, while anti-EBV-VCA IgG was raised 3 weeks later. Rabbit lymphomas and their cell lines contained EBV-DNA and expressed EBV-encoded RNA-1 (EBER-1). Rabbit lymphoma cell lines, most of which have specific chromosomal abnormality, showed tumorigenicity in nude mice. The second is the first animal model for EBV-infected T-cell LPD with virus-associated hemophagocytic syndrome (VAHS), using rabbits infected with an EBV-like herpesvirus, Herpesvirus papio (HVP). Rabbits inoculated intravenously with HVP-producing cells showed increased anti-EBV-VCA-IgG titers, and most (85%) subsequently died of fatal LPD and VAHS, with bleeding and hepatosplenomegaly, during 22-105 days. Peroral spray of cell-free HVP induced viral infection with seroconversion in 3 out of 5 rabbits, with 2 of the 3 infected rabbits dying of LPD with VAHS. Atypical T lymphocytes containing HVP-DNA and expressing EBER-1 were observed in many organs. Hemophagocytic histiocytosis was observed in the lymph nodes, spleen, bone marrow, and thymus. These rabbit models are also useful and inexpensive alternative experimental model systems for studying the biology and pathogenesis of EBV, and prophylactic and therapeutic regimens.

In vitro atrazine-exposure inhibits human natural killer cell lytic granule release

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rowe, Alexander M.; Brundage, Kathleen M.; Center for Immunopathology and Microbial Pathogenesis, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV 26506

2007-06-01

The herbicide atrazine is a known immunotoxicant and an inhibitor of human natural killer (NK) cell lytic function. The precise changes in NK cell lytic function following atrazine exposure have not been fully elucidated. The current study identifies the point at which atrazine exerts its affect on the stepwise process of human NK cell-mediated lyses of the K562 target cell line. Using intracellular staining of human peripheral blood lymphocytes, it was determined that a 24-h in vitro exposure to atrazine did not decrease the level of NK cell lytic proteins granzyme A, granzyme B or perforin. Thus, it was hypothesizedmore » that atrazine exposure was inhibiting the ability of the NK cells to bind to the target cell and subsequently inhibit the release of lytic protein from the NK cell. To test this hypothesis, flow cytometry and fluorescent microscopy were employed to analyze NK cell-target cell co-cultures following atrazine exposure. These assays demonstrated no significant decrease in the level of target cell binding. However, the levels of NK intracellular lytic protein retained and the amount of lytic protein released were assessed following a 4-h incubation with K562 target cells. The relative level of intracellular lytic protein was 25-50% higher, and the amount of lytic protein released was 55-65% less in atrazine-treated cells than vehicle-treated cells following incubation with the target cells. These results indicate that ATR exposure inhibits the ability of NK cells to lyse target cells by blocking lytic granule release without affecting the ability of the NK cell to form stable conjugates with target cells.« less

Comparative genome analysis of novel Podoviruses lytic for hypermucoviscous Klebsiella pneumoniae of K1, K2, and K57 capsular types.

PubMed

Solovieva, Ekaterina V; Myakinina, Vera P; Kislichkina, Angelina A; Krasilnikova, Valentina M; Verevkin, Vladimir V; Mochalov, Vladimir V; Lev, Anastasia I; Fursova, Nadezhda K; Volozhantsev, Nikolay V

2018-01-02

Hypermucoviscous (HV) strains of capsular types K1, K2 and K57 are the most virulent representatives of the Klebsiella pneumoniae species. Eight novel bacteriophages lytic for HV K. pneumoniae were isolated and characterized. Three bacteriophages, KpV41, KpV475, and KpV71 were found to have a lytic activity against mainly K. pneumoniae of capsular type K1. Two phages, KpV74, and KpV763 were lytic for K2 capsular type K. pneumoniae, and the phage KpV767 was specific to K57-type K. pneumoniae only. Two more phages, KpV766, and KpV48 had no capsular specificity. The phage genomes consist of a linear double-stranded DNA of 40,395-44,623bp including direct terminal repeats of 180-246 bp. The G + C contents are 52.3-54.2 % that is slightly lower than that of genomes of K. pneumoniae strains being used for phage propagation. According to the genome structures, sequence similarity and phylogenetic data, the phages are classified within the genus Kp32virus and Kp34virus of subfamily Autographivirinae, family Podoviridae. In the phage genomes, genes encoding proteins with putative motifs of polysaccharide depolymerase were identified. Depolymerase genes of phages KpV71 and KpV74 lytic for hypermucoviscous K. pneumoniae of K1 and K2 capsular type, respectively, were cloned and expressed in Escherichia coli, and the recombinant gene products were purified. The specificity and polysaccharide-degrading activity of the recombinant depolymerases were demonstrated. Copyright © 2017 Elsevier B.V. All rights reserved.

Measurement of Epstein-Barr virus DNA load using a novel quantification standard containing two EBV DNA targets and SYBR Green I dye.

PubMed

Lay, Meav-Lang J; Lucas, Robyn M; Ratnamohan, Mala; Taylor, Janette; Ponsonby, Anne-Louise; Dwyer, Dominic E

2010-09-22

Reactivation of Epstein-Barr virus (EBV) infection may cause serious, life-threatening complications in immunocompromised individuals. EBV DNA is often detected in EBV-associated disease states, with viral load believed to be a reflection of virus activity. Two separate real-time quantitative polymerase chain reaction (QPCR) assays using SYBR Green I dye and a single quantification standard containing two EBV genes, Epstein-Barr nuclear antigen-1 (EBNA-1) and BamHI fragment H rightward open reading frame-1 (BHRF-1), were developed to detect and measure absolute EBV DNA load in patients with various EBV-associated diseases. EBV DNA loads and viral capsid antigen (VCA) IgG antibody titres were also quantified on a population sample. EBV DNA was measurable in ethylenediaminetetraacetic acid (EDTA) whole blood, peripheral blood mononuclear cells (PBMCs), plasma and cerebrospinal fluid (CSF) samples. EBV DNA loads were detectable from 8.0 × 10(2) to 1.3 × 10(8) copies/ml in post-transplant lymphoproliferative disease (n = 5), 1.5 × 10(3) to 2.0 × 10(5) copies/ml in infectious mononucleosis (n = 7), 7.5 × 10(4) to 1.1 × 10(5) copies/ml in EBV-associated haemophagocytic syndrome (n = 1), 2.0 × 10(2) to 5.6 × 10(3) copies/ml in HIV-infected patients (n = 12), and 2.0 × 10(2) to 9.1 × 10(4) copies/ml in the population sample (n = 218). EBNA-1 and BHRF-1 DNA were detected in 11.0% and 21.6% of the population sample respectively. There was a modest correlation between VCA IgG antibody titre and BHRF-1 DNA load (rho = 0.13, p = 0.05) but not EBNA-1 DNA load (rho = 0.11, p = 0.11). Two sensitive and specific real-time PCR assays using SYBR Green I dye and a single quantification standard containing two EBV DNA targets, were developed for the detection and measurement of EBV DNA load in a variety of clinical samples. These assays have application in the investigation of EBV-related illnesses in immunocompromised individuals.

EBV seroepidemiology in married and unmarried women and men in Iran.

PubMed

Pourahamad, Morteza; Hooshmand, Farhang; Olyaee Nezhad, Sara; Sepidkar, Abdolali

2014-04-01

Among the eight known human herpes viruses, Epstein- Barr virus (EBV) is considered to be sexually transmissible. This study was conducted to evaluate the seroepidemiology of this infection in married and unmarried Iranian couples. In this comparative observational and cross-sectional study, 160 men and women were divided into married and unmarried groups. Serum IgG and IgM antibodies to the EBV viral capsid antigen were analyzed by Enzyme-linked Immunosorbent Assays (ELISAs). In this study 78 men and 82 women were enrolled. Ninety percent of the married and 76.2% of the unmarried women were anti-EBV IgG positive (P = 0.08), while 80% of the married and 94% of the unmarried men were antiEBV IgG positive (P = 0.052). Seroepidemiology of EBV is not significantly different in married vs. unmarried women and men in Iran; therefore, sexual contact may not be the primary mechanism of EBV transmission in Iran and other developing countries. Attention to other possible routes of transmission is recommended.

EBV-Positive Lymphoproliferations of B- T- and NK-Cell Derivation in Non-Immunocompromised Hosts

PubMed Central

Fend, Falko

2018-01-01

The contribution of Epstein-Barr virus (EBV) to the development of specific types of benign lymphoproliferations and malignant lymphomas has been extensively studied since the discovery of the virus over the last 50 years. The importance and better understanding of the EBV-associated lymphoproliferative disorders (LPD) of B, T or natural killer (NK) cell type has resulted in the recognition of new entities like EBV+ mucocutaneous ulcer or the addition of chronic active EBV (CAEBV) infection in the revised 2016 World Health Organization (WHO) lymphoma classification. In this article, we review the definitions, morphology, pathogenesis, and evolving concepts of the various EBV-associated disorders including EBV+ diffuse large B-cell lymphoma, not otherwise specified (DLBCL, NOS), EBV+ mucocutaneous ulcer, DLBCL associated with chronic inflammation, fibrin-associated DLBCL, lymphomatoid granulomatosis, the EBV+ T and NK-cell LPD of childhood, aggressive NK leukaemia, extranodal NK/T-cell lymphoma, nasal type, and the new provisional entity of primary EBV+ nodal T- or NK-cell lymphoma. The current knowledge regarding the pathogenesis of B-cell lymphomas that can be EBV-associated including Burkitt lymphoma, plasmablastic lymphoma and classic Hodgkin lymphoma will be also explored. PMID:29518976

Stress-induced reactivation of Epstein-Barr virus in astronauts

NASA Technical Reports Server (NTRS)

Stowe, R. P.; Pierson, D. L.; Feeback, D. L.; Barrett, A. D.

2000-01-01

Herpesviruses are leading causes of infectious blindness and death in immunocompromised individuals. Impaired cellular immunity, which is known to result in increased frequency and severity of herpesvirus infections, has been demonstrated both during and after spaceflight. Therefore, we examined whether Epstein-Barr virus (EBV), a well-characterized latent herpesvirus, undergoes reactivation in astronauts. Sera from Shuttle astronauts, taken before and after spaceflight, were examined for evidence of EBV reactivation. The geometric mean antibody titer to EBV viral capsid antigen (VCA) was significantly increased prior to flight compared to baseline (p = 0. 0001). After spaceflight, evidence of acute lytic replication was found in which 8- to 64-fold increases in EBV early antigen (EA) antibodies occurred without significant increases in antibodies to measles virus. Additionally, stress-induced shifts in circulating leukocytes and elevated levels of urinary cortisol and epinephrine were found. Overall, significant increases in EA or high VCA/EA antibody titers were found in 8 of 23 (35%) male astronauts and 3 of 5 (60%) female astronauts. These results indicate that stress reactivates EBV prior to flight and suggest that acute lytic replication of EBV occurs during spaceflight. Copyright 2000 S. Karger AG, Basel.

CD95 (Fas) ligand expression of Epstein-Barr virus (EBV)-infected lymphocytes: a possible mechanism of immune evasion in chronic active EBV infection.

PubMed

Ohshima, K; Suzumiya, J; Sugihara, M; Nagafuchi, S; Ohga, S; Kikuchi, M

1999-01-01

The Epstein-Barr virus (EBV) induces infectious mononucleosis (IM) and can be associated with chronic active EBV infection (CAEBV). Cytotoxic T lymphocytes (CTL) play an important role in excluding EBV-infected cells. Two cytotoxic mechanisms of CTL have been demonstrated: one perforin/granzyme-based and the other Fas (CD95)/Fas ligand (FasL)-based. To clarify these two pathways in CAEBV, we analyzed six patients with CAEBV and four patients with IM using immunohistochemical staining of the lymph nodes. In both CAEBV and IM, CD8+ T-cells increased in number, but CD56+ natural killer cells were rare. In four of six cases with CAEBV, approximately half the lymphocytes were positive for T cell-restricted intracellular antigens (TIA-1), which were recognized by the cytolytic granules of CTL. In IM, the number of TIA-1 positive cells was smaller than that in CAEBV. Fas-positive lymphocytes were frequently encountered in both CAEBV and IM. However, FasL-positive lymphocytes increased in three of six patients with CAEBV, but not in patients with IM. Except for one case with CAEBV, the number of perforin- and/or granzyme-positive cells was small in number in both CAEBV and IM cases. In double-staining FasL and EBV in situ hybridization, FasL-positive EBV-infected lymphocytes were detected in CAEBV but not in IM. In CAEBV, the Fas/FasL pathway and not perforin pathways appears to play an important role in the pathogenesis. The data suggest that EBV-infected lymphocytes may evade immune attack through the expression of FasL.

[Aggressive primary cutaneous B-cell lymphomas and novel EBV+ entities].

PubMed

Lamos, C; Dippel, E

2017-09-01

Primary cutaneous large B‑cell lymphomas (PCBLT), EBV-positive large B‑cell lymphomas, not otherwise specified (EBV+ DLBCL, NOS), and primary cutaneous intravascular large B‑cell lymphomas (PCIVLBL) are recognized as cutaneous lymphomas with intermediate to poor prognosis. Differentiation from indolent B‑cell lymphomas or other pathologies of the skin can be complex, both clinically and histologically, but vital for the outcome of the patient. The combination of immunotherapy and polychemotherapy regimens, such as R‑CHOP, has led to significant improvements in prognosis, especially in diffuse large B‑cell lymphomas. Therapeutic decisions need to be individually made for each patient, ideally within an interdisciplinary tumor conference. Immunosenescence may be an important factor in the pathogenesis of EBV+ DLBCL, NOS in elderly individuals. Their prognosis is less favorable than that of patients with EBV-negative PCBLT, whereby this has been observed particularly in elderly patients. One third of patients with PCIVLBL progress to systemic disease. The occurrence of nodal manifestation is rarely observed. Symptoms may vary depending on the organ system involved. Currently there are no evidence-based therapy recommendations due to the rarity of the disease. EBV-positive mucocutaneous ulcer is a new provisional category in the current WHO classification for lymphoid neoplasms. It has been segregated from EBV+ DLBCL, NOS due to its self-limiting course and good response to conservative therapy.

Molecular Pathogenesis of EBV Susceptibility in XLP as Revealed by Analysis of Female Carriers with Heterozygous Expression of SAP

PubMed Central

Palendira, Umaimainthan; Low, Carol; Chan, Anna; Hislop, Andrew D.; Ho, Edwin; Phan, Tri Giang; Deenick, Elissa; Cook, Matthew C.; Riminton, D. Sean; Choo, Sharon; Loh, Richard; Alvaro, Frank; Booth, Claire; Gaspar, H. Bobby; Moretta, Alessandro; Khanna, Rajiv; Rickinson, Alan B.; Tangye, Stuart G.

2011-01-01

X-linked lymphoproliferative disease (XLP) is a primary immunodeficiency caused by mutations in SH2D1A which encodes SAP. SAP functions in signalling pathways elicited by the SLAM family of leukocyte receptors. A defining feature of XLP is exquisite sensitivity to infection with EBV, a B-lymphotropic virus, but not other viruses. Although previous studies have identified defects in lymphocytes from XLP patients, the unique role of SAP in controlling EBV infection remains unresolved. We describe a novel approach to this question using female XLP carriers who, due to random X-inactivation, contain both SAP+ and SAP− cells. This represents the human equivalent of a mixed bone marrow chimera in mice. While memory CD8+ T cells specific for CMV and influenza were distributed across SAP+ and SAP− populations, EBV-specific cells were exclusively SAP+. The preferential recruitment of SAP+ cells by EBV reflected the tropism of EBV for B cells, and the requirement for SAP expression in CD8+ T cells for them to respond to Ag-presentation by B cells, but not other cell types. The inability of SAP− clones to respond to Ag-presenting B cells was overcome by blocking the SLAM receptors NTB-A and 2B4, while ectopic expression of NTB-A on fibroblasts inhibited cytotoxicity of SAP− CD8+ T cells, thereby demonstrating that SLAM receptors acquire inhibitory function in the absence of SAP. The innovative XLP carrier model allowed us to unravel the mechanisms underlying the unique susceptibility of XLP patients to EBV infection in the absence of a relevant animal model. We found that this reflected the nature of the Ag-presenting cell, rather than EBV itself. Our data also identified a pathological signalling pathway that could be targeted to treat patients with severe EBV infection. This system may allow the study of other human diseases where heterozygous gene expression from random X-chromosome inactivation can be exploited. PMID:22069374

Viral Carcinogenesis Beyond Malignant Transformation: EBV in the Progression of Human Cancers

PubMed Central

Müller-Coan, Bárbara G.; Pagano, Joseph S.

2017-01-01

Cancer progression begins when malignant cells colonize adjacent sites, and it is characterized by increasing tumor heterogeneity, invasion and dissemination of cancer cells. Clinically, progression is the most relevant stage in the natural history of cancers. A given virus is usually regarded as oncogenic because of its ability to induce malignant transformation of cells. Nonetheless, oncogenic viruses may also be important for the progression of infection-associated cancers. Recently this hypothesis has been addressed because of studies on the contribution of the Epstein–Barr virus (EBV) to the aggressiveness of nasopharyngeal carcinoma (NPC). Several EBV products modulate cancer progression phenomena, such as the epithelial–mesenchymal transition, cell motility, invasiveness, angiogenesis, and metastasis. In this regard, there are compelling data about the effects of EBV latent membrane proteins (LMPs) and EBV nuclear antigens (EBNAs), as well as nontranslated viral RNAs, such as the EBV-encoded small nonpolyadenylated RNAs (EBERs) and viral microRNAs, notably EBV miR-BARTs. The available data on the mechanisms and players involved in the contribution of EBV infection to the aggressiveness of NPC are discussed in this review. Overall, this conceptual framework may be valuable for the understanding of the contribution of some infectious agents in the progression of cancers. PMID:27068530

A model of lytic, latent, and reactivating varicella-zoster virus infections in isolated enteric neurons.

PubMed

Gershon, Anne A; Chen, Jason; Gershon, Michael D

2008-03-01

Because human primary afferent neurons are not readily obtained, we sought to develop a model in which the lytic, latent, and reactivating phases of varicella-zoster virus (VZV) infection were recapitulated in neurons from an animal source. Enteric neurons were obtained from the small intestine of adult guinea pigs and from the bowel of fetal mice. Latency was established when these neurons were infected by cell-free VZV in the absence of fibroblasts or other cells of mesodermal origin. In contrast, lytic infection ensued when fibroblasts were present or when the enteric neurons were infected by cell-associated VZV. Latency was associated with the expression of a limited subset of viral genes, the products of which were restricted to the cytoplasm. Lysis was associated with the expression of viral glycoproteins, nuclear translocation of latency-associated gene products, and rapid cell death. Reactivation was accomplished by expressing VZV open reading frame (ORF) 61p or herpes simplex virus ICP0 in latently infected neurons. Isolated enteric neurons from guinea pigs and mice recapitulate latent gene expression in human cranial nerve and dorsal root ganglia. Expression of latency-associated VZV gene products was detected in 88% of samples of adult human intestine, suggesting that VZV not only infects enteric neurons but also is latent in the human enteric nervous system. This in vitro model should facilitate further understanding of latency and reactivation of VZV.

Potential of a lytic bacteriophage to disrupt Acinetobacter baumannii biofilms in vitro.

PubMed

Liu, Yannan; Mi, Zhiqiang; Niu, Wenkai; An, Xiaoping; Yuan, Xin; Liu, Huiying; Wang, Yong; Feng, Yuzhong; Huang, Yong; Zhang, Xianglilan; Zhang, Zhiyi; Fan, Hang; Peng, Fan; Li, Puyuan; Tong, Yigang; Bai, Changqing

2016-10-01

The ability of Acinetobacter baumannii to form biofilms and develop antibiotic resistance makes it difficult to control infections caused by this bacterium. In this study, we explored the potential of a lytic bacteriophage to disrupt A. baumannii biofilms. The potential of the lytic bacteriophage to disrupt A. baumannii biofilms was assessed by performing electron microscopy, live/dead bacterial staining, crystal violet staining and by determining adenosine triphosphate release. The bacteriophage inhibited the formation of and disrupted preformed A. baumannii biofilms. Results of disinfection assay showed that the lytic bacteriophage lysed A. baumannii cells suspended in blood or grown on metal surfaces. These results suggest the potential of the lytic bacteriophage to disrupt A. baumannii biofilms.

The Translesion Polymerase Pol η Is Required for Efficient Epstein-Barr Virus Infectivity and Is Regulated by the Viral Deubiquitinating Enzyme BPLF1

PubMed Central

Dyson, Ossie F.; Pagano, Joseph S.

2017-01-01

ABSTRACT Epstein-Barr virus (EBV) infection and lytic replication are known to induce a cellular DNA damage response. We previously showed that the virally encoded BPLF1 protein interacts with and regulates several members of the translesion synthesis (TLS) pathway, a DNA damage tolerance pathway, and that these cellular factors enhance viral infectivity. BPLF1 is a late lytic cycle gene, but the protein is also packaged in the viral tegument, indicating that BPLF1 may function both early and late during infection. The BPLF1 protein expresses deubiquitinating activity that is strictly conserved across the Herpesviridae; mutation of the active site cysteine results in a loss of enzymatic activity. Infection with an EBV BPLF1 knockout virus results in decreased EBV infectivity. Polymerase eta (Pol η), a specialized DNA repair polymerase, functions in TLS and allows for DNA replication complexes to bypass lesions in DNA. Here we report that BPLF1 interacts with Pol η and that Pol η protein levels are increased in the presence of functional BPLF1. BPLF1 promotes a nuclear relocalization of Pol η molecules which are focus-like in appearance, consistent with the localization observed when Pol η is recruited to sites of DNA damage. Knockdown of Pol η resulted in decreased production of infectious virus, and further, Pol η was found to bind to EBV DNA, suggesting that it may allow for bypass of damaged viral DNA during its replication. The results suggest a mechanism by which EBV recruits cellular repair factors, such as Pol η, to sites of viral DNA damage via BPLF1, thereby allowing for efficient viral DNA replication. IMPORTANCE Epstein-Barr virus is the causative agent of infectious mononucleosis and infects approximately 90% of the world's population. It causes lymphomas in individuals with acquired and innate immune disorders and is strongly associated with Hodgkin's lymphoma, Burkitt's lymphoma, diffuse large B-cell lymphomas, nasopharyngeal carcinoma (NPC

The Translesion Polymerase Pol η Is Required for Efficient Epstein-Barr Virus Infectivity and Is Regulated by the Viral Deubiquitinating Enzyme BPLF1.

PubMed

Dyson, Ossie F; Pagano, Joseph S; Whitehurst, Christopher B

2017-10-01

Epstein-Barr virus (EBV) infection and lytic replication are known to induce a cellular DNA damage response. We previously showed that the virally encoded BPLF1 protein interacts with and regulates several members of the translesion synthesis (TLS) pathway, a DNA damage tolerance pathway, and that these cellular factors enhance viral infectivity. BPLF1 is a late lytic cycle gene, but the protein is also packaged in the viral tegument, indicating that BPLF1 may function both early and late during infection. The BPLF1 protein expresses deubiquitinating activity that is strictly conserved across the Herpesviridae ; mutation of the active site cysteine results in a loss of enzymatic activity. Infection with an EBV BPLF1 knockout virus results in decreased EBV infectivity. Polymerase eta (Pol η), a specialized DNA repair polymerase, functions in TLS and allows for DNA replication complexes to bypass lesions in DNA. Here we report that BPLF1 interacts with Pol η and that Pol η protein levels are increased in the presence of functional BPLF1. BPLF1 promotes a nuclear relocalization of Pol η molecules which are focus-like in appearance, consistent with the localization observed when Pol η is recruited to sites of DNA damage. Knockdown of Pol η resulted in decreased production of infectious virus, and further, Pol η was found to bind to EBV DNA, suggesting that it may allow for bypass of damaged viral DNA during its replication. The results suggest a mechanism by which EBV recruits cellular repair factors, such as Pol η, to sites of viral DNA damage via BPLF1, thereby allowing for efficient viral DNA replication. IMPORTANCE Epstein-Barr virus is the causative agent of infectious mononucleosis and infects approximately 90% of the world's population. It causes lymphomas in individuals with acquired and innate immune disorders and is strongly associated with Hodgkin's lymphoma, Burkitt's lymphoma, diffuse large B-cell lymphomas, nasopharyngeal carcinoma (NPC), and

Degradation of phosphorylated p53 by viral protein-ECS E3 ligase complex.

PubMed

Sato, Yoshitaka; Kamura, Takumi; Shirata, Noriko; Murata, Takayuki; Kudoh, Ayumi; Iwahori, Satoko; Nakayama, Sanae; Isomura, Hiroki; Nishiyama, Yukihiro; Tsurumi, Tatsuya

2009-07-01

p53-signaling is modulated by viruses to establish a host cellular environment advantageous for their propagation. The Epstein-Barr virus (EBV) lytic program induces phosphorylation of p53, which prevents interaction with MDM2. Here, we show that induction of EBV lytic program leads to degradation of p53 via an ubiquitin-proteasome pathway independent of MDM2. The BZLF1 protein directly functions as an adaptor component of the ECS (Elongin B/C-Cul2/5-SOCS-box protein) ubiquitin ligase complex targeting p53 for degradation. Intringuingly, C-terminal phosphorylation of p53 resulting from activated DNA damage response by viral lytic replication enhances its binding to BZLF1 protein. Purified BZLF1 protein-associated ECS could be shown to catalyze ubiquitination of phospho-mimetic p53 more efficiently than the wild-type in vitro. The compensation of p53 at middle and late stages of the lytic infection inhibits viral DNA replication and production during lytic infection, suggesting that the degradation of p53 is required for efficient viral propagation. Taken together, these findings demonstrate a role for the BZLF1 protein-associated ECS ligase complex in regulation of p53 phosphorylated by activated DNA damage signaling during viral lytic infection.

Roles of germination-specific lytic enzymes CwlJ and SleB in Bacillus anthracis.

PubMed

Heffron, Jared D; Orsburn, Benjamin; Popham, David L

2009-04-01

The structural characteristics of a spore enable it to withstand stresses that typically kill a vegetative cell. Spores remain dormant until small molecule signals induce them to germinate into vegetative bacilli. Germination requires degradation of the thick cortical peptidoglycan by germination-specific lytic enzymes (GSLEs). Bacillus anthracis has four putative GSLEs, based upon sequence similarities with enzymes in other species: SleB, CwlJ1, CwlJ2, and SleL. In this study, the roles of SleB, CwlJ1, and CwlJ2 were examined. The expression levels of all three genes peak 3.5 h into sporulation. Genetic analysis revealed that, similar to other known GSLEs, none of these gene products are individually required for growth, sporulation, or triggering of germination. However, later germination events are affected in spores lacking CwlJ1 or SleB. Compared to the wild type, germinating spores without CwlJ1 suffer a delay in optical density loss and cortex peptidoglycan release. The absence of SleB also causes a delay in cortex fragment release. A double mutant lacking both SleB and CwlJ1 is completely blocked in cortex hydrolysis and progresses through outgrowth to produce colonies at a frequency 1,000-fold lower than that of the wild-type strain. A null mutation eliminating CwlJ2 has no effect on germination. High-performance liquid chromatography and mass spectroscopy analysis revealed that SleB is required for lytic transglycosylase activity. CwlJ1 also clearly participates in cortex hydrolysis, but its specific mode of action remains unclear. Understanding the lytic germination activities that naturally diminish spore resistance can lead to methods for prematurely inducing them, thus simplifying the process of treating contaminated sites.

Infectious mononucleosis accompanied by clonal proliferation of EBV-infected cells and infection of CD8-positive cells.

PubMed

Arai, Ayako; Yamaguchi, Takeshi; Komatsu, Honami; Imadome, Ken-Ichi; Kurata, Morito; Nagata, Kaoru; Miura, Osamu

2014-01-01

A 22-year-old male was admitted for a sustained fever of 2 months, lymphadenopathy, and liver dysfunction. Anti-VCA-IgM antibody was positive, with elevated Epstein-Barr virus (EBV)-DNA load in the peripheral blood. Liver biopsy revealed infiltration of CD8-positive and EBV-positive cells. Most peripheral blood mononuclear cells (PBMCs) were also positive for CD8, and showed detectable levels of EBV-DNA. Monoclonal proliferation of EBV-infected cells was detected in the PBMCs by Southern blotting for EBV-terminal repeat (EBV-TR). Although EBV-positive T-cell lymphoproliferative disease (EBV-T-LPD) was suspected, the symptoms spontaneously resolved within 12 months. Anti-VCA-IgM antibody and the clonal band of EBV-TR were negative 1 year after the onset, while anti-EBNA antibody was positive. The final diagnosis was thus confirmed as infectious mononucleosis (IM). Our results indicate that EBV-infected CD8-positive cells and clonal proliferation of EBV-infected cells may be temporally detected in IM. EBV-T-LPDs should be carefully excluded in such cases.

Deficient EBV-specific B- and T-cell response in patients with chronic fatigue syndrome.

PubMed

Loebel, Madlen; Strohschein, Kristin; Giannini, Carolin; Koelsch, Uwe; Bauer, Sandra; Doebis, Cornelia; Thomas, Sybill; Unterwalder, Nadine; von Baehr, Volker; Reinke, Petra; Knops, Michael; Hanitsch, Leif G; Meisel, Christian; Volk, Hans-Dieter; Scheibenbogen, Carmen

2014-01-01

Epstein-Barr virus (EBV) has long been discussed as a possible cause or trigger of Chronic Fatigue Syndrome (CFS). In a subset of patients the disease starts with infectious mononucleosis and both enhanced and diminished EBV-specific antibody titers have been reported. In this study, we comprehensively analyzed the EBV-specific memory B- and T-cell response in patients with CFS. While we observed no difference in viral capsid antigen (VCA)-IgG antibodies, EBV nuclear antigen (EBNA)-IgG titers were low or absent in 10% of CFS patients. Remarkably, when analyzing the EBV-specific memory B-cell reservoir in vitro a diminished or absent number of EBNA-1- and VCA-antibody secreting cells was found in up to 76% of patients. Moreover, the ex vivo EBV-induced secretion of TNF-α and IFN-γ was significantly lower in patients. Multicolor flow cytometry revealed that the frequencies of EBNA-1-specific triple TNF-α/IFN-γ/IL-2 producing CD4(+) and CD8(+) T-cell subsets were significantly diminished whereas no difference could be detected for HCMV-specific T-cell responses. When comparing EBV load in blood immune cells, we found more frequently EBER-DNA but not BZLF-1 RNA in CFS patients compared to healthy controls suggesting more frequent latent replication. Taken together, our findings give evidence for a deficient EBV-specific B- and T-cell memory response in CFS patients and suggest an impaired ability to control early steps of EBV reactivation. In addition the diminished EBV response might be suitable to develop diagnostic marker in CFS.

Do EBV Encoded Small RNAs Interfere with Tumor Suppressor APC in EBV Associated Breast Cancers

DTIC Science & Technology

2006-08-01

acute infectious mononucleosis but ultimately establishes persistent lifetime latent infection. In all latently infected cells EBVexpresses two small non...human initially causes acute infectious mononucleosis and later establishes persistent lifetime latent infection. In all latently EBV-infected cells, only

Defective activity of Epstein-Barr virus (EBV) specific cytotoxic T lymphocytes in children with chronic active EBV infection and in their parents.

PubMed

Fujieda, M; Wakiguchi, H; Hisakawa, H; Kubota, H; Kurashige, T

1993-10-01

Antibodies of Epstein-Barr virus (EBV), EBV-specific cytotoxic T lymphocyte (EBVCTL) activity and the lymphocyte subset of CTL were examined in 13 Japanese children with chronic active EBV infection (CAEBV) and their parents (eight fathers and 10 mothers). Anti-virus-capsid antigen (VCA)-IgG antibody titers ranged from 1:640 to 1:5120 in the patients with CAEBV and from 1:40 to 1:640 in the parents. While anti-VCA-IgM antibody was detected in three patients, anti-VCA-IgA antibody in five and anti-early-antigen (EA)-IgG antibody in 11, no antibody was detected in the parents except anti-EA antibody, which was positive in the mothers of cases 5 and 13 (1:10 and 1:40). Anti-EBV-associated nuclear antigen (EBNA) antibody was < or = 1:10 in six out of 13 patients with CAEBV and in 10 out of 18 parents tested. Epstein-Barr virus activity was significantly lower (P < 0.005) both in the children with CAEBV and in their parents than in seropositive age-matched controls. Proportions of a CTL subset (CD8+ CD11- lymphocytes) in the patients with CAEBV were significantly higher (P < 0.005) than in controls, while those in the parents were at the same level as in controls. Defective EBVCTL activity and anti-EBNA-antibody responses were frequently observed both in children with CAEBV and in their parents, which may suggest that the abnormal immune response to EBV may be based on a familial disorder, though no familial involvement has been reported in Japanese children with CAEBV.

HLA class I polymorphisms are associated with development of infectious mononucleosis upon primary EBV infection.

PubMed

McAulay, Karen A; Higgins, Craig D; Macsween, Karen F; Lake, Annette; Jarrett, Ruth F; Robertson, Faye L; Williams, Hilary; Crawford, Dorothy H

2007-10-01

Infectious mononucleosis (IM) is an immunopathological disease caused by EBV that occurs in young adults and is a risk factor for Hodgkin lymphoma (HL). An association between EBV-positive HL and genetic markers in the HLA class I locus has been identified, indicating that genetic differences in the HLA class I locus may alter disease phenotypes associated with EBV infection. To further determine whether HLA class I alleles may affect development of EBV-associated diseases, we analyzed 2 microsatellite markers and 2 SNPs located near the HLA class I locus in patients with acute IM and in asymptomatic EBV-seropositive and -seronegative individuals. Alleles of both microsatellite markers were significantly associated with development of IM. Specific alleles of the 2 SNPs were also significantly more frequent in patients with IM than in EBV-seronegative individuals. IM patients possessing the associated microsatellite allele had fewer lymphocytes and increased neutrophils relative to IM patients lacking the allele. These patients also displayed higher EBV titers and milder IM symptoms. The results of this study indicate that HLA class I polymorphisms may predispose patients to development of IM upon primary EBV infection, suggesting that genetic variation in T cell responses can influence the nature of primary EBV infection and the level of viral persistence.

HLA class I polymorphisms are associated with development of infectious mononucleosis upon primary EBV infection

PubMed Central

McAulay, Karen A.; Higgins, Craig D.; Macsween, Karen F.; Lake, Annette; Jarrett, Ruth F.; Robertson, Faye L.; Williams, Hilary; Crawford, Dorothy H.

2007-01-01

Infectious mononucleosis (IM) is an immunopathological disease caused by EBV that occurs in young adults and is a risk factor for Hodgkin lymphoma (HL). An association between EBV-positive HL and genetic markers in the HLA class I locus has been identified, indicating that genetic differences in the HLA class I locus may alter disease phenotypes associated with EBV infection. To further determine whether HLA class I alleles may affect development of EBV-associated diseases, we analyzed 2 microsatellite markers and 2 SNPs located near the HLA class I locus in patients with acute IM and in asymptomatic EBV-seropositive and -seronegative individuals. Alleles of both microsatellite markers were significantly associated with development of IM. Specific alleles of the 2 SNPs were also significantly more frequent in patients with IM than in EBV-seronegative individuals. IM patients possessing the associated microsatellite allele had fewer lymphocytes and increased neutrophils relative to IM patients lacking the allele. These patients also displayed higher EBV titers and milder IM symptoms. The results of this study indicate that HLA class I polymorphisms may predispose patients to development of IM upon primary EBV infection, suggesting that genetic variation in T cell responses can influence the nature of primary EBV infection and the level of viral persistence. PMID:17909631

A multiplex calibrated real-time PCR assay for quantitation of DNA of EBV-1 and 2.

PubMed

Gatto, Francesca; Cassina, Giulia; Broccolo, Francesco; Morreale, Giuseppe; Lanino, Edoardo; Di Marco, Eddi; Vardas, Efthiya; Bernasconi, Daniela; Buttò, Stefano; Principi, Nicola; Esposito, Susanna; Scarlatti, Gabriella; Lusso, Paolo; Malnati, Mauro S

2011-12-01

Accurate and highly sensitive tests for the diagnosis of active Epstein-Barr virus (EBV) infection are essential for the clinical management of individuals infected with EBV. A calibrated quantitative real-time PCR assay for the measurement of EBV DNA of both EBV-1 and 2 subtypes was developed, combining the detection of the EBV DNA and a synthetic DNA calibrator in a multiplex PCR format. The assay displays a wide dynamic range and a high degree of accuracy even in the presence of 1μg of human genomic DNA. This assay measures with the same efficiency EBV DNA from strains prevalent in different geographic areas. The clinical sensitivity and specificity of the system were evaluated by testing 181 peripheral blood mononuclear cell (PBMCs) and plasma specimens obtained from 21 patients subjected to bone marrow transplantation, 70 HIV-seropositive subjects and 23 healthy controls. Patients affected by EBV-associated post-transplant lymphoprolipherative disorders had the highest frequency of EBV detection and the highest viral load. Persons infected with HIV had higher levels of EBV DNA load in PBMCs and a higher frequency of EBV plasma viremia compared to healthy controls. In conclusion, this new assay provides a reliable high-throughput method for the quantitation of EBV DNA in clinical samples. Copyright © 2011 Elsevier B.V. All rights reserved.

A Rare Case of Chronic Active Epstein-Barr Virus (EBV) Infection Accompanied by the Infiltration of EBV-infected CD8+ T Cells into the Muscle.

PubMed

Kobayashi, Nobuhiko; Mitsui, Takeki; Ogawa, Yoshiyuki; Iriuchishima, Hirono; Takizawa, Makiko; Yokohama, Akihiko; Saitoh, Takayuki; Koiso, Hiromi; Tsukamoto, Norifumi; Murakami, Hirokazu; Nojima, Yoshihisa; Handa, Hiroshi

2018-04-01

We describe a rare case of chronic active Epstein-Barr virus (CAEBV) infection, with infiltration of the skeletal muscle. A 19-year-old woman with swollen cervical lymph nodes and a fever was referred to our hospital. Swelling of the trapezium muscle and elevation of creatinine kinase level were observed. Biopsy results of the brachialis muscle revealed infiltration of Epstein-Barr virus (EBV)-encoded RNA-positive CD8 T lymphocytes. The EBV virus load in the peripheral blood was high, and EBV monoclonality was determined by Southern blot analysis. Owing to the rarity of CAEBV with skeletal muscle infiltration, this case alerts physicians to the potential diagnostic pitfalls of CAEBV.

Establishment and operation of a Good Manufacturing Practice-compliant allogeneic Epstein-Barr virus (EBV)-specific cytotoxic cell bank for the treatment of EBV-associated lymphoproliferative disease

PubMed Central

Vickers, Mark A; Wilkie, Gwen M; Robinson, Nicolas; Rivera, Nadja; Haque, Tanzina; Crawford, Dorothy H; Barry, Jacqueline; Fraser, Neil; Turner, David M; Robertson, Victoria; Dyer, Phil; Flanagan, Peter; Newlands, Helen R; Campbell, John; Turner, Marc L

2014-01-01

Epstein-Barr virus (EBV) is associated with several malignancies, including post-transplant lymphoproliferative disorder (PTLD). Conventional treatments for PTLD are often successful, but risk organ rejection and cause significant side effects. EBV-specific cytotoxic T lymphocytes (CTLs) generated in vitro from peripheral blood lymphocytes provide an alternative treatment modality with few side effects, but autologous CTLs are difficult to use in clinical practice. Here we report the establishment and operation of a bank of EBV-specific CTLs derived from 25 blood donors with human leucocyte antigen (HLA) types found at high frequency in European populations. Since licensure, there have been enquiries about 37 patients, who shared a median of three class I and two class II HLA types with these donors. Cells have been infused into ten patients with lymphoproliferative disease, eight of whom achieved complete remission. Neither patient with refractory disease was matched for HLA class II. Both cases of EBV-associated non-haematopoietic sarcoma receiving cells failed to achieve complete remission. Thirteen patients died before any cells could be issued, emphasizing that the bank should be contacted before patients become pre-terminal. Thus, this third party donor-derived EBV-specific CTL cell bank can supply most patients with appropriately matched cells and most recipients have good outcomes. PMID:25066775

Lytic and Chemotactic Features of the Plaque-Forming Bacterium KD531 on Phaeodactylum tricornutum

PubMed Central

Chen, Zhangran; Zheng, Wei; Yang, Luxi; Boughner, Lisa A.; Tian, Yun; Zheng, Tianling; Xu, Hong

2017-01-01

Phaeodactylum tricornutum is a dominant bloom forming species and potential biofuel feedstock. To control P. tricornutum bloom or to release lipids from P. tricornutum, we previously screened and identified the lytic bacterium Labrenzia sp. KD531 toward P. tricornutum. In the present study, we evaluated the lytic activity of Labrenzia sp. KD531 on microalgae and investigated its lytic mechanism. The results indicated that the lytic activity of KD531 was temperature- and pH-dependent, but light-independent. In addition to P. tricornutum, KD531 also showed lytic activity against other algal species, especially green algae. A quantitative analysis of algal cellular protein, carbohydrate and lipid content together with measurements of dry weight after exposure to bacteria-infected algal lysate indicated that the bacterium KD531 influenced the algal biomass by disrupting the algal cells. Both chemotactic analysis and microscopic observations of subsamples from different regions of formed plaques showed that KD531 could move toward and then directly contact algal cells. Direct contact between P. tricornutum and KD531 cells was essential for the lytic process. PMID:29312256

157 Pathogenesis of Epstein-Barr Virus-driven lymphomas of HIV+ patients: new insights of potential clinical relevance

PubMed Central

Dolcetti, Riccardo

2014-01-01

Human Immunodeficiency Virus (HIV)+ patients have an increased risk to develop lymphomas, including a significant fraction of histotypes associated with Epstein-Barr Virus (EBV) infection. Although restoration of EBV-specific T-cell function induced by HAART has led to a decreased incidence of the more immunogenic EBV-associated lymphomas, such as immunoblastic and primary central nervous system lymphomas, other EBV+ histotypes are still prevalent in the HAART era, particularly Hodgkin’s lymphoma. Therefore, factors other than HIV-induced immune suppression are probably required for the development of EBV-related lymphomas in this setting. Particular attention is being given to the identification of microenvironmental stimuli able to up-regulate critical EBV latency proteins or to induce/enhance EBV replication. In fact, recent evidence indicates that, although latency programs predominate in EBV-driven tumors, lytic EBV replication may also be of pathogenic relevance, at least in the early phases of cell transformation. This is particularly relevant for HIV-related lymphomagenesis since the underlying impairment of immune responses may favour uncontrolled activation of EBV lytic replication in latently-infected B lymphocytes. Available data indicate that local expression of distinct cytokines, including IL-4 and IL-13, may up-regulate the expression of the LMP-1 oncoprotein in B cells, thus favoring lymphomagenesis. In the search of microenvironmental factors that may promote the development of EBV-driven lymphomas in HIV+ patients, we obtained evidence supporting a pathogenic role for HIV matrix protein p17, which accumulates in lymphoid tissues of HIV+ individuals, even during HAART. Our findings support a direct contribution of HIV p17 to the development of EBV-driven lymphomagenesis and may provide the rationale for new strategies of clinical intervention in this setting.

Development of Drugs for Epstein - Barr virus using High-Throughput in silico Virtual Screening

PubMed Central

Li, Ning; Thompson, Scott; Jiang, Hualiang; Lieberman, Paul M.; Luo, Cheng

2010-01-01

Importance of the field Epstein-Barr virus (EBV) is a ubiquitious human herpesvirus that is causally associated with endemic forms of Burkitt’s lymphoma (BL), nasopharyngeal carcinoma, and lymphoproliferative disease in immunosuppressed individuals. On a global scale, EBV infects over 90% of the adult population and is responsible for ~1% of all human cancers. To date, there is no efficacious drug or therapy for the treatment of EBV infection and EBV-related diseases. Areas covered in this review In this review, we discuss the existing anti-EBV inhibitors and those under development. We discuss the value of different molecular targets, including EBV lytic DNA replication enzymes, as well as proteins that are expressed exclusively during latent infection, like EBNA1 and LMP1. Since the atomic structure of the EBNA1 DNA binding domain has been described, it is an attractive target for in silico methods of drug design and small molecule screening. We discuss the use of computational methods that can greatly facilitate the development of novel inhibitors and how in silico screening methods can be applied to target proteins with known structures, like EBNA1, to treat EBV infection and disease. What the reader will gain The reader will be familiarized with the problems in targeting of EBV for inhibition by small molecules and how computational methods can greatly facilitate this process. Take home message Despite the impressive efficacy of nucleoside analogues for the treatment of herpesvirus lytic infection, there remain few effective treatments for latent infections. Since EBV-latent infection persists within and contributes to the formation of EBV-associated cancers, targeting EBV latent proteins is an unmet medical need. High throughput in silico screening can accelerate the process of drug discovery for novel and selective agents that inhibit EBV latent infection and associated disease. PMID:22822721

Identification and characterization of EBV genomes in spontaneously immortalized human peripheral blood B lymphocytes by NGS technology.

PubMed

Lei, Haiyan; Li, Tianwei; Hung, Guo-Chiuan; Li, Bingjie; Tsai, Shien; Lo, Shyh-Ching

2013-11-19

We conducted genomic sequencing to identify Epstein Barr Virus (EBV) genomes in 2 human peripheral blood B lymphocytes that underwent spontaneous immortalization promoted by mycoplasma infections in culture, using the high-throughput sequencing (HTS) Illumina MiSeq platform. The purpose of this study was to examine if rapid detection and characterization of a viral agent could be effectively achieved by HTS using a platform that has become readily available in general biology laboratories. Raw read sequences, averaging 175 bps in length, were mapped with DNA databases of human, bacteria, fungi and virus genomes using the CLC Genomics Workbench bioinformatics tool. Overall 37,757 out of 49,520,834 total reads in one lymphocyte line (# K4413-Mi) and 28,178 out of 45,335,960 reads in the other lymphocyte line (# K4123-Mi) were identified as EBV sequences. The two EBV genomes with estimated 35.22-fold and 31.06-fold sequence coverage respectively, designated K4413-Mi EBV and K4123-Mi EBV (GenBank accession number KC440852 and KC440851 respectively), are characteristic of type-1 EBV. Sequence comparison and phylogenetic analysis among K4413-Mi EBV, K4123-Mi EBV and the EBV genomes previously reported to GenBank as well as the NA12878 EBV genome assembled from database of the 1000 Genome Project showed that these 2 EBVs are most closely related to B95-8, an EBV previously isolated from a patient with infectious mononucleosis and WT-EBV. They are less similar to EBVs associated with nasopharyngeal carcinoma (NPC) from Hong Kong and China as well as the Akata strain of a case of Burkitt's lymphoma from Japan. They are most different from type 2 EBV found in Western African Burkitt's lymphoma.

Biopsy-proven case of Epstein-Barr virus (EBV)-associated vasculitis of the central nervous system.

PubMed

Kano, Kohei; Katayama, Takayuki; Takeguchi, Shiori; Asanome, Asuka; Takahashi, Kae; Saito, Tsukasa; Sawada, Jun; Saito, Masato; Anei, Ryogo; Kamada, Kyousuke; Miyokawa, Naoyuki; Nishihara, Hiroshi; Hasebe, Naoyuki

2017-06-01

A 75-year-old woman was admitted to our hospital with rapidly deteriorating consciousness disturbance. She had a 7-year history of rheumatoid arthritis (RA), which had been treated with methotrexate (MTX) and prednisolone. Brain T2-weighted MRI showed diffuse high-intensity lesions in the cerebral subcortical and deep white matter, bilateral basal ganglia and thalamus. A cerebrospinal fluid examination revealed elevated protein levels and positive Epstein-Barr virus (EBV) DNA. Human immunodeficiency virus was negative. Brain biopsy showed perivascular lymphocytic infiltration in the parenchyma and meninx with EBV-encoded small RNA (EBER). Since this case did not fulfill the criteria for chronic active EBV infection (CAEBV), she was diagnosed with Epstein-Barr virus (EBV)-associated vasculitis of the central nervous system. High-dose methylprednisolone, acyclovir, ganciclovir and foscarnet were not effective. Although EBV is a causative agent of infectious mononucleosis (IM), lymphomas and nasopharyngeal carcinomas, vasculitic pathology of the central nervous system with EBV reactivation in the elderly is rare. Immunosuppressive drugs such as steroids and MTX are widely used to treat autoimmune disorders, but may exacerbate the reactivation of EBV. This is the first case of biopsy-proven EBV-positive/HIV-negative vasculitis during the treatment of RA with MTX and steroids. This case indicates that EBV-associated vasculitis needs to be considered as a differential diagnosis of CNS vasculitis. © 2016 Japanese Society of Neuropathology.

A microRNA signature profile in EBV+ diffuse large B-cell lymphoma of the elderly

PubMed Central

de Andrade, Tathiana Azevedo; Evangelista, Adriane Feijo; Campos, Antonio Hugo Froes; Poles, Wagner Augusto; Borges, Natalia Morais; Camillo, Claudia Malheiros Coutinho; Soares, Fernando Augusto; Vassallo, Jose; Paes, Roberto Pinto; Zerbini, Maria Claudia; Scapulatempo, Cristovam; Alves, Antonio Correa

2014-01-01

Currently, there is no characteristic microRNA (miRNA) expression pattern in Epstein-Barr virus+ diffuse large B-cell lymphoma of the elderly (EBV+DLBCLe). This study aims to characterize a signature profile and identify miRNAs that can be used as biomarkers and alternative therapeutic targets for EBV+DLBCLe. Seventy-one DLBCL patients aged 50 years and older were included and four EBV+ and four EBV– samples were analyzed in two miRNA array platforms (pilot study). A larger multicenter cohort (29 EBV+DLBCLe and 65 EBV–DLBCL patients) was used to validate the results by real-time polymerase chain reaction. In the pilot study, 9% of DLBCL were EBV+DLBCLe by in situ hybridization. In multicenter study, EBV+DLBCLe group showed a predominance of non-germinal center B-cell origin. Overall survival duration of EBV+DLBCLe was significantly inferior to that of EBV–DLBCL patients. We found 10 deregulated miRNAs in the two groups, but only seven were statistically different. We confirmed overexpression of hsa-miR-126, hsa-miR-146a, hsa-miR-146b, hsa-miR-150, and hsa-miR-222 and underexpression of hsa-miR-151 in EBV+DLBCLe cases compared to EBV–DLBCL cases. Hsa-miR-146b and hsa-miR-222 showed high specificity for identifying EBV+DLBCLe. The present study proposed a miRNA signature for EBV+DLBCLe and our findings suggest that hsa-miR-146b and hsa-miR-222 could be biomarkers and therapeutic targets. PMID:25544772

Pathogenic Role of Exosomes in Epstein-Barr Virus (EBV)-Associated Cancers

PubMed Central

Teow, Sin-Yeang; Liew, Kitson; Khoo, Alan Soo-Beng; Peh, Suat-Cheng

2017-01-01

Exosomes are 40- to 100-nm membrane-bound small vesicles that carry a great variety of cellular cargoes including proteins, DNA, messenger RNAs (mRNAs), and microRNAs (miRNAs). These nanovesicles are detected in various biological fluids such as serum, urine, saliva, and seminal fluids. Exosomes serve as key mediators in intercellular communication by facilitating the transfer and exchange of cellular components from cells to cells. They contain various pathogenic factors whereby their adverse effects have been implicated in multiple viral infections and cancers. Interestingly, accumulating evidences showed that exosomes derived from tumour viruses or oncoviruses, exacerbate virus-associated cancers by remodelling the tumour microenvironment. In this review, we summarize the contributing factors of Epstein-Barr virus (EBV) products-containing exosomes in viral pathogenesis and their potential implications in EBV-driven malignancies. Understanding the biological role of these exosomes in the disease would undoubtedly boost the development of a more comprehensive strategy to combat EBV-associated cancers and to better predict the therapeutic outcomes. Furthermore, we also highlight the potentials and challenges of EBV products-containing exosomes being employed as diagnostic markers and therapeutic targets for EBV-related cancers. Since these aspects are rather underexplored, we attempt to underline interesting areas that warrant further investigations in the future. PMID:29104494

Coexistence of age-related EBV-associated follicular hyperplasia and large B-cell EBV+ lymphoma of the elderly. Two distinct features of the same T-cell dysfunction related to senescence?

PubMed

Gibier, Jean-Baptiste; Bouchindhomme, Brigitte; Dubois, Romain; Hivert, Benedicte; Grardel, Nathalie; Copin, Marie-Christine

2017-03-01

Age-related EBV-associated lymphoproliferative disorders form a new clinicopathological group. Until recently, this group was associated with diffuse large B-cell lymphoma (DLBCL), characterised by an aggressive clinical presentation and a poor prognosis. Recent findings in Western Caucasian patients, however, suggest that this entity covers a wide spectrum of diseases, ranging from reactive follicular hyperplasia (HR) to DLBCL. We report the case of an 85-year-old Caucasian man showing lymphadenopathy and numerous hypodense lesions of the liver. Examination of a lymph node revealed follicular hyperplasia with EBV expression confined to germinal centres. The patient was treated with Rituximab and subsequently, the lesions of the liver were explored. They showed extensive necrosis and a polymorphic large B-cell population with strong EBV expression. This is the first report to describe age-related EBV-associated follicular hyperplasia at one site coexisting with DLBCL at another. This case warrants undertaking further investigations each time a diagnosis of age-related EBV-HR is associated with extranodal lesions. Copyright © 2016 Elsevier GmbH. All rights reserved.

Establishment and operation of a Good Manufacturing Practice-compliant allogeneic Epstein-Barr virus (EBV)-specific cytotoxic cell bank for the treatment of EBV-associated lymphoproliferative disease.

PubMed

Vickers, Mark A; Wilkie, Gwen M; Robinson, Nicolas; Rivera, Nadja; Haque, Tanzina; Crawford, Dorothy H; Barry, Jacqueline; Fraser, Neil; Turner, David M; Robertson, Victoria; Dyer, Phil; Flanagan, Peter; Newlands, Helen R; Campbell, John; Turner, Marc L

2014-11-01

Epstein-Barr virus (EBV) is associated with several malignancies, including post-transplant lymphoproliferative disorder (PTLD). Conventional treatments for PTLD are often successful, but risk organ rejection and cause significant side effects. EBV-specific cytotoxic T lymphocytes (CTLs) generated in vitro from peripheral blood lymphocytes provide an alternative treatment modality with few side effects, but autologous CTLs are difficult to use in clinical practice. Here we report the establishment and operation of a bank of EBV-specific CTLs derived from 25 blood donors with human leucocyte antigen (HLA) types found at high frequency in European populations. Since licensure, there have been enquiries about 37 patients, who shared a median of three class I and two class II HLA types with these donors. Cells have been infused into ten patients with lymphoproliferative disease, eight of whom achieved complete remission. Neither patient with refractory disease was matched for HLA class II. Both cases of EBV-associated non-haematopoietic sarcoma receiving cells failed to achieve complete remission. Thirteen patients died before any cells could be issued, emphasizing that the bank should be contacted before patients become pre-terminal. Thus, this third party donor-derived EBV-specific CTL cell bank can supply most patients with appropriately matched cells and most recipients have good outcomes. © 2014 The Authors. British Journal of Haematology published by John Wiley & Sons Ltd.

Seroprevalence of Anti-EBV IgG among Various Age Groups from Khon Kaen Province, Thailand.

PubMed

Suntornlohanakul, Rabporn; Wanlapakorn, Nasamon; Vongpunsawad, Sompong; Thongmee, Thanunrat; Chansaenroj, Jira; Poovorawan, Yong

2015-01-01

Epstein-Barr virus (EBV) is an extremely common herpesvirus that may cause asymptomatic infection or various diseases, including infectious mononucleosis, certain lymphoproliferative diseases and several types of neoplasms. Vaccine development is an important strategy to reduce the burden of EBV-associated diseases and the timing of vaccinations should be before primary infection occurs. In the past, more than 90% of Thai children were infected with EBV in early childhood. Now, due to the improved healthcare system in Thailand, we aim to determine current prevalence of EBV infection among people in different age groups. A total of 538 sera were collected from residents of Khon Kaen province in northeastern Thailand for detecting anti-EBV IgG. Sera of infants under 2-years-old were also tested for anti-EBV IgM and EBV-DNA. The prevalence of anti-EBV IgG was 47.1% (95% CI: 23.3-70.8) in infants aged 0-6 months, 34.9% (95% CI: 23.1-46.7) in those aged 6-24 months, 87.9% (95% CI: 79.5-96.3) in children aged 3-5 years and then maintained at above 95% through adulthood. These seropositivity rates among Thai children remain similar to those found in a previous study conducted 20 years ago. Thai children are still exposed to EBV from an early age. Therefore, a prophylactic vaccine should be given within the first two years of life.

Common cytological and cytogenetic features of Epstein-Barr virus (EBV)-positive natural killer (NK) cells and cell lines derived from patients with nasal T/NK-cell lymphomas, chronic active EBV infection and hydroa vacciniforme-like eruptions.

PubMed

Zhang, Yu; Nagata, Hiroshi; Ikeuchi, Tatsuro; Mukai, Hiroyuki; Oyoshi, Michiko K; Demachi, Ayako; Morio, Tomohiro; Wakiguchi, Hiroshi; Kimura, Nobuhiro; Shimizu, Norio; Yamamoto, Kohtaro

2003-06-01

In this study, we describe the cytological and cytogenetic features of six Epstein-Barr virus (EBV)-infected natural killer (NK) cell clones. Three cell clones, SNK-1, -3 and -6, were derived from patients with nasal T/NK-cell lymphomas; two cell clones, SNK-5 and -10, were isolated from patients with chronic active EBV infection (CAEBV); and the other cell clone, SNK-11, was from a patient with hydroa vacciniforme (HV)-like eruptions. An analysis of the number of EBV-terminal repeats showed that the SNK cell clones had monoclonal EBV genomes identical to the original EBV-infected cells of the respective patients, and SNK cells had the type II latency of EBV infection, suggesting that not only the cell clones isolated from nasal T/NK-cell lymphomas but also those isolated from CAEBV and HV-like eruptions had been transformed by EBV to a certain degree. Cytogenetic analysis detected deletions in chromosome 6q in five out of the six SNK cell clones, while 6q was not deleted in four control cell lines of T-cell lineage. This suggested that a 6q deletion is a characteristic feature of EBV-positive NK cells, which proliferated in the diseased individuals. The results showed that EBV-positive NK cells in malignant and non-malignant lymphoproliferative diseases shared common cytological and cytogenetic features.

PiggyBac-mediated Cancer Immunotherapy Using EBV-specific Cytotoxic T-cells Expressing HER2-specific Chimeric Antigen Receptor

PubMed Central

Nakazawa, Yozo; Huye, Leslie E; Salsman, Vita S; Leen, Ann M; Ahmed, Nabil; Rollins, Lisa; Dotti, Gianpietro; Gottschalk, Stephen M; Wilson, Matthew H; Rooney, Cliona M

2011-01-01

Epstein-Barr virus (EBV)-specific cytotoxic T lymphocytes (CTLs) can be modified to function as heterologous tumor directed effector cells that survive longer in vivo than tumor directed T cells without virus specificity, due to chronic stimulation by viral antigens expressed during persistent infection in seropositive individuals. We evaluated the nonviral piggyBac (PB) transposon system as a platform for modifying EBV-CTLs to express a functional human epidermal growth factor receptor 2-specific chimeric antigen receptor (HER2-CAR) thereby directing virus-specific, gene modified CTLs towards HER2-positive cancer cells. Peripheral blood mononuclear cells (PBMCs) were nucleofected with transposons encoding a HER2-CAR and a truncated CD19 molecule for selection followed by specific activation and expansion of EBV-CTLs. HER2-CAR was expressed in ~40% of T cells after CD19 selection with retention of immunophenotype, polyclonality, and function. HER2-CAR-modified EBV-CTLs (HER2-CTLs) killed HER2-positive brain tumor cell lines in vitro, exhibited transient and reversible increases in HER2-CAR expression following antigen-specific stimulation, and stably expressed HER2-CAR beyond 120 days. Adoptive transfer of PB-modified HER2-CTLs resulted in tumor regression in a murine xenograft model. Our results demonstrate that PB can be used to redirect virus-specific CTLs to tumor targets, which should prolong tumor-specific T cell survival in vivo producing more efficacious immunotherapy. PMID:21772253

PiggyBac-mediated cancer immunotherapy using EBV-specific cytotoxic T-cells expressing HER2-specific chimeric antigen receptor.

PubMed

Nakazawa, Yozo; Huye, Leslie E; Salsman, Vita S; Leen, Ann M; Ahmed, Nabil; Rollins, Lisa; Dotti, Gianpietro; Gottschalk, Stephen M; Wilson, Matthew H; Rooney, Cliona M

2011-12-01

Epstein-Barr virus (EBV)-specific cytotoxic T lymphocytes (CTLs) can be modified to function as heterologous tumor directed effector cells that survive longer in vivo than tumor directed T cells without virus specificity, due to chronic stimulation by viral antigens expressed during persistent infection in seropositive individuals. We evaluated the nonviral piggyBac (PB) transposon system as a platform for modifying EBV-CTLs to express a functional human epidermal growth factor receptor 2-specific chimeric antigen receptor (HER2-CAR) thereby directing virus-specific, gene modified CTLs towards HER2-positive cancer cells. Peripheral blood mononuclear cells (PBMCs) were nucleofected with transposons encoding a HER2-CAR and a truncated CD19 molecule for selection followed by specific activation and expansion of EBV-CTLs. HER2-CAR was expressed in ~40% of T cells after CD19 selection with retention of immunophenotype, polyclonality, and function. HER2-CAR-modified EBV-CTLs (HER2-CTLs) killed HER2-positive brain tumor cell lines in vitro, exhibited transient and reversible increases in HER2-CAR expression following antigen-specific stimulation, and stably expressed HER2-CAR beyond 120 days. Adoptive transfer of PB-modified HER2-CTLs resulted in tumor regression in a murine xenograft model. Our results demonstrate that PB can be used to redirect virus-specific CTLs to tumor targets, which should prolong tumor-specific T cell survival in vivo producing more efficacious immunotherapy.

Frequency of EBV LMP-1 Promoter and Coding Variations in Burkitt Lymphoma Samples in Africa and South America and Peripheral Blood in Uganda.

PubMed

Liao, Hsiao-Mei; Liu, Hebing; Lei, Heiyan; Li, Bingjie; Chin, Pei-Ju; Tsai, Shien; Bhatia, Kishor; Gutierrez, Marina; Epelman, Sidnei; Biggar, Robert J; Nkrumah, Francis; Neequaye, Janet; Ogwang, Martin D; Reynolds, Steven J; Lo, Shyh-Ching; Mbulaiteye, Sam M

2018-06-02

Epstein-Barr virus (EBV) is linked to several cancers, including endemic Burkitt lymphoma (eBL), but causal variants are unknown. We recently reported novel sequence variants in the LMP-1 gene and promoter in EBV genomes sequenced from 13 of 14 BL biopsies. Alignments of the novel sequence variants for 114 published EBV genomes, including 27 from BL cases, revealed four LMP-1 variant patterns, designated A to D. Pattern A variant was found in 48% of BL EBV genomes. Here, we used PCR-Sanger sequencing to evaluate 50 additional BL biopsies from Ghana, Brazil, and Argentina, and peripheral blood samples from 113 eBL cases and 115 controls in Uganda. Pattern A was found in 60.9% of 64 BL biopsies evaluated. Compared to PCR-negative subjects in Uganda, detection of Pattern A in peripheral blood was associated with eBL case status (odds ratio [OR] 31.7, 95% confidence interval: 6.8⁻149), controlling for relevant confounders. Variant Pattern A and Pattern D were associated with eBL case status, but with lower ORs (9.7 and 13.6, respectively). Our results support the hypothesis that EBV LMP-1 Pattern A may be associated with eBL, but it is not the sole associated variant. Further research is needed to replicate and elucidate our findings.

Changing patterns in the Epstein-Barr virus (EBV)and Hodgkin lymphoma association in Tunisia.

PubMed

Dhiab, Myriam Ben; Ziadi, Sonia; Saad, Hanene; Louhichi, Teheni; Trimeche, Mounir

2016-09-01

We compared the features of the Epstein-Barr virus (EBV) and Hodgkin lymphoma (HL) association in Tunisia in two periods of time, 1991-2001 (111 cases) and 2002-2012 (122 cases). The investigation of the EBV status by EBER in situ hybridization showed a significant decrease in the prevalence of EBV-positive HL from 69.3 % for the period 1991-2001 to 40.1 % for the 2002-2012 period (p = 0.00001). EBV positivity has decreased in all age groups but was more pronounced among young patients, in the 15-24-year age group (46.1 vs 10.3 %, p = 0.003), in the 25-34-year age group (56.2 vs 25 %, p = 0.04), and among children (88.4 vs 59.2 %, p = 0.01). This decrease in EBV-positive HL over time contrasted with a remarkable increase in EBV-negative HL in young adults aged 15-34 years (51.2 vs 83 %; p = 0.001), especially among women (59.1 vs 91.2 %; p = 0.01). The decrease in EBV-positive HL over time concerns particularly the nodular sclerosis histological subtype (69.2 vs 31.6 %, p = 0.000001). These results indicate that the epidemiology of HL and its association with EBV are changing over time, with a trend toward a Western profile, and point toward the emergence of other environmental causative factors, especially among young women, which remain to be identified.

Natural Variation of Epstein-Barr Virus Genes, Proteins, and Primary MicroRNA.

PubMed

Correia, Samantha; Palser, Anne; Elgueta Karstegl, Claudio; Middeldorp, Jaap M; Ramayanti, Octavia; Cohen, Jeffrey I; Hildesheim, Allan; Fellner, Maria Dolores; Wiels, Joelle; White, Robert E; Kellam, Paul; Farrell, Paul J

2017-08-01

Viral gene sequences from an enlarged set of about 200 Epstein-Barr virus (EBV) strains, including many primary isolates, have been used to investigate variation in key viral genetic regions, particularly LMP1, Zp, gp350, EBNA1, and the BART microRNA (miRNA) cluster 2. Determination of type 1 and type 2 EBV in saliva samples from people from a wide range of geographic and ethnic backgrounds demonstrates a small percentage of healthy white Caucasian British people carrying predominantly type 2 EBV. Linkage of Zp and gp350 variants to type 2 EBV is likely to be due to their genes being adjacent to the EBNA3 locus, which is one of the major determinants of the type 1/type 2 distinction. A novel classification of EBNA1 DNA binding domains, named QCIGP, results from phylogeny analysis of their protein sequences but is not linked to the type 1/type 2 classification. The BART cluster 2 miRNA region is classified into three major variants through single-nucleotide polymorphisms (SNPs) in the primary miRNA outside the mature miRNA sequences. These SNPs can result in altered levels of expression of some miRNAs from the BART variant frequently present in Chinese and Indonesian nasopharyngeal carcinoma (NPC) samples. The EBV genetic variants identified here provide a basis for future, more directed analysis of association of specific EBV variations with EBV biology and EBV-associated diseases. IMPORTANCE Incidence of diseases associated with EBV varies greatly in different parts of the world. Thus, relationships between EBV genome sequence variation and health, disease, geography, and ethnicity of the host may be important for understanding the role of EBV in diseases and for development of an effective EBV vaccine. This paper provides the most comprehensive analysis so far of variation in specific EBV genes relevant to these diseases and proposed EBV vaccines. By focusing on variation in LMP1, Zp, gp350, EBNA1, and the BART miRNA cluster 2, new relationships with the known

Serological profiling of the EBV immune response in Chronic Fatigue Syndrome using a peptide microarray.

PubMed

Loebel, Madlen; Eckey, Maren; Sotzny, Franziska; Hahn, Elisabeth; Bauer, Sandra; Grabowski, Patricia; Zerweck, Johannes; Holenya, Pavlo; Hanitsch, Leif G; Wittke, Kirsten; Borchmann, Peter; Rüffer, Jens-Ulrich; Hiepe, Falk; Ruprecht, Klemens; Behrends, Uta; Meindl, Carola; Volk, Hans-Dieter; Reimer, Ulf; Scheibenbogen, Carmen

2017-01-01

Epstein-Barr-Virus (EBV) plays an important role as trigger or cofactor for various autoimmune diseases. In a subset of patients with Chronic Fatigue Syndrome (CFS) disease starts with infectious mononucleosis as late primary EBV-infection, whereby altered levels of EBV-specific antibodies can be observed in another subset of patients. We performed a comprehensive mapping of the IgG response against EBV comparing 50 healthy controls with 92 CFS patients using a microarray platform. Patients with multiple sclerosis (MS), systemic lupus erythematosus (SLE) and cancer-related fatigue served as controls. 3054 overlapping peptides were synthesised as 15-mers from 14 different EBV proteins. Array data was validated by ELISA for selected peptides. Prevalence of EBV serotypes was determined by qPCR from throat washing samples. EBV type 1 infections were found in patients and controls. EBV seroarray profiles between healthy controls and CFS were less divergent than that observed for MS or SLE. We found significantly enhanced IgG responses to several EBNA-6 peptides containing a repeat sequence in CFS patients compared to controls. EBNA-6 peptide IgG responses correlated well with EBNA-6 protein responses. The EBNA-6 repeat region showed sequence homologies to various human proteins. Patients with CFS had a quite similar EBV IgG antibody response pattern as healthy controls. Enhanced IgG reactivity against an EBNA-6 repeat sequence and against EBNA-6 protein is found in CFS patients. Homologous sequences of various human proteins with this EBNA-6 repeat sequence might be potential targets for antigenic mimicry.

[The clinical value of immunological markers of EBV infection in children with infectious mononucleosis].

PubMed

Kurtasova, L M; Ol'khovskiĭ, I A; Iakunina, E Iu; Golovanova, A E; Zablotskaia, S G

2005-12-01

A hundred and sixteen patients aged 1 to 14 years who had infectious mononucleosis (IM) caused by the Epstein-Barr virus (EBV) were followed up in its acute phase and 3, 6, and 12 months after the disease experienced by them. The clinical significance of the markers of EBV infection was assessed in children with IM. The high diagnostic capacity of detection of EBV DNA in the lymphocytes was established in patients with IM. It was shown that it is necessary to use the serological markers of EBV infection to monitor the course of this disease in children.

Lytic bacteriophages reduce Escherichia coli O157

PubMed Central

Ferguson, Sean; Roberts, Cheryl; Handy, Eric; Sharma, Manan

2013-01-01

The role of lytic bacteriophages in preventing cross contamination of produce has not been evaluated. A cocktail of three lytic phages specific for E. coli O157:H7 (EcoShield™) or a control (phosphate buffered saline, PBS) was applied to lettuce by either; (1) immersion of lettuce in 500 ml of EcoShield™ 8.3 log PFU/ml or 9.8 log PFU/ml for up to 2 min before inoculation with E. coli O157:H7; (2) spray-application of EcoShield™ (9.3 log PFU/ml) to lettuce after inoculation with E. coli O157:H7 (4.10 CFU/cm2) following exposure to 50 μg/ml chlorine for 30 sec. After immersion studies, lettuce was spot-inoculated with E. coli O157:H7 (2.38 CFU/cm2). Phage-treated, inoculated lettuce pieces were stored at 4°C for and analyzed for E. coli O157:H7 populations for up to 7 d. Immersion of lettuce in 9.8 log PFU/ml EcoShield™ for 2 min significantly (p < 0.05) reduced E. coli O157:H7 populations after 24 h when stored at 4°C compared with controls. Immersion of lettuce in suspensions containing high concentrations of EcoShield™ (9.8 log PFU/ml) resulted in the deposition of high concentrations (7.8 log log PFU/cm2) of bacteriophages on the surface of fresh cut lettuce, potentially contributing to the efficacy of the lytic phages on lettuce. Spraying phages on to inoculated fresh cut lettuce after being washed in hypochlorite solution was significantly more effective in reducing E. coli O157:H7 populations (2.22 log CFU/cm2) on day 0 compared with control treatments (4.10 log CFU/cm2). Both immersion and spray treatments provided protection from E. coli O157:H7 contamination on lettuce, but spray application of lytic bacteriophages to lettuce was more effective in immediately reducing E. coli O157:H7 populations fresh cut lettuce. PMID:23819106

Comparison of EBV DNA viral load in whole blood, plasma, B-cells and B-cell culture supernatant.

PubMed

Ouedraogo, David Eric; Bollore, Karine; Viljoen, Johannes; Foulongne, Vincent; Reynes, Jacques; Cartron, Guillaume; Vendrell, Jean-Pierre; Van de Perre, Philippe; Tuaillon, Edouard

2014-05-01

Epstein-Barr virus (EBV) genome quantitation in whole blood is used widely for therapeutic monitoring of EBV-associated disorders in immunosuppressed individuals and in patients with EBV-associated lymphoma. However, the most appropriate biological material to be used for EBV DNA quantitation remains a subject of debate. This study compare the detection rate and levels of EBV DNA from whole blood, plasma, enriched B-cells, and B-cell short-term culture supernatant using quantitative real-time PCR. Samples were collected from 33 subjects with either HIV infection or B-cell lymphoma. Overall, EBV DNA was detected in 100% of enriched B-cell samples, in 82% of B-cell culture supernatants, in 57% of plasma, and 42% of whole blood samples. A significant correlation for EBV viral load was found between enriched B-cell and B-cell culture supernatant material (ρ = 0.92; P < 0.0001), but no significant correlation existed between EBV DNA levels in whole blood and enriched B-cells (ρ = -0.02; P = 0.89), whole blood and plasma (ρ = 0.24; P = 0.24), or enriched B-cells and plasma (ρ = 0.08; P = 0.77). Testing of enriched B-cells appeared to be the most sensitive method for detection of EBV DNA as well as for exploration of the cellular reservoir. Quantitation of EBV DNA in plasma and B-cell culture supernatant may be of interest to assess EBV reactivation dynamics and response to treatment as well as to decipher EBV host-pathogen interactions in various clinical scenarios. © 2013 Wiley Periodicals, Inc.

Clinicopathological characteristics of four cases of EBV positive T-cell lymphoproliferative disorders of childhood in China

PubMed Central

Huang, Wenting; Lv, Ning; Ying, Jianming; Qiu, Tian; Feng, Xiaoli

2014-01-01

A new category, “EBV positive T-cell lymphoproliferative disorders (LPD) of childhood”, was proposed in the 2008 World Health Organization’s (WHO) classifications of lymphoma. This series of lymphoproliferative disorders is rare. There are two major types of this series of disorders: systemic EBV positive T-cell LPD of childhood and hydroa vacciniforme-like lymphoma (HVLL). In this study, we describe the distinct features of four cases of EBV positive T-cell LPD of childhood in China. Two were systemic EBV positive T-cell LPD of childhood, one was HVLL and one was chronic active EBV (CAEBV). The main manifestations were lymphadenopathy, fever, hepatosplenomegaly and skin rashes. The structure of the lymph nodes in the patients ranged from preserved to partially or totally destroyed. Small- to medium-sized, atypical T cells had infiltrated the lymph nodes. In HVLL, the neoplastic cells had infiltrated the dermis and subcutaneous region surrounding sweat glands and nerves. All of the cases tested positive for CD8, other T cells, cytotoxic markers and EBV-encoded RNA (EBER) without CD56 expression. Molecular analysis was performed in three cases. All of the three analyses showed a TCRγ rearrangement and one case also had an IGH rearrangement. One of the patients with systemic EBV positive T-cell LPD of childhood experienced rapid evolved and died within five months of onset. CAEBV, systemic EBV-positive T-cell LPD of childhood and HVLL are distinct but overlapping diseases within the category of EBV-positive T-cell LPD of childhood. They constitute a continuous spectrum of EBV-infected associated disorders. PMID:25197370

Immunology: Is Actin at the Lytic Synapse a Friend or a Foe?

PubMed

Hammer, John A

2018-02-19

Cytotoxic T cells and natural killer cells defend us against disease by secreting lytic granules. Whether actin facilitates or thwarts lytic granule secretion has been an open question. Recent results now indicate that the answer depends on the maturation stage of the immune cell-target cell contact. Published by Elsevier Ltd.

Epstein-Barr virus (EBV)-encoded dUTPase and chronic restraint induce impaired learning and memory and sickness responses.

PubMed

Aubrecht, Taryn G; Weil, Zachary M; Ariza, Maria Eugenia; Williams, Marshall; Reader, Brenda F; Glaser, Ronald; Sheridan, John F; Nelson, Randy J

2014-10-01

Most adult humans have been infected with Epstein-Barr virus (EBV) and carry the latent virus. The EBV genome codes for several proteins that form an early antigen complex important for viral replication; one of these proteins is deoxyuridine triphosphate nucleotidohydrolase (dUTPase). The EBV-encoded dUTPase can induce sickness responses in mice. Because stress can increase latent virus reactivation, we hypothesized that chronic restraint would exacerbate sickness behaviors elicited by EBV-encoded dUTPase. Male Swiss-Webster mice were injected daily for 15 days with either saline or EBV-encoded dUTPase. Additionally, half of the mice from each condition were either restrained for 3h daily or left undisturbed. Restraint stress impaired learning and memory in the passive avoidance chamber; impaired learning and memory was due to EBV-encoded dUTPase injected into restrained mice. EBV-encoded dUTPase induced sickness responses and restraint stress interacts with EBV-encoded dUTPase to exacerbate the sickness response. These data support a role for EBV-encoded dUTPase and restraint stress in altering the pathophysiology of EBV independent of viral replication. Copyright © 2014 Elsevier Inc. All rights reserved.

Epstein-Barr virus recombinants from overlapping cosmid fragments.

PubMed

Tomkinson, B; Robertson, E; Yalamanchili, R; Longnecker, R; Kieff, E

1993-12-01

Five overlapping type 1 Epstein-Barr virus (EBV) DNA fragments constituting a complete replication- and transformation-competent genome were cloned into cosmids and transfected together into P3HR-1 cells, along with a plasmid encoding the Z immediate-early activator of EBV replication. P3HR-1 cells harbor a type 2 EBV which is unable to transform primary B lymphocytes because of a deletion of DNA encoding EBNA LP and EBNA 2, but the P3HR-1 EBV can provide replication functions in trans and can recombine with the transfected cosmids. EBV recombinants which have the type 1 EBNA LP and 2 genes from the transfected EcoRI-A cosmid DNA were selectively and clonally recovered by exploiting the unique ability of the recombinants to transform primary B lymphocytes into lymphoblastoid cell lines. PCR and immunoblot analyses for seven distinguishing markers of the type 1 transfected DNAs identified cell lines infected with EBV recombinants which had incorporated EBV DNA fragments beyond the transformation marker-rescuing EcoRI-A fragment. Approximately 10% of the transforming virus recombinants had markers mapping at 7, 46 to 52, 93 to 100, 108 to 110, 122, and 152 kbp from the 172-kbp transfected genome. These recombinants probably result from recombination among the transfected cosmid-cloned EBV DNA fragments. The one recombinant virus examined in detail by Southern blot analysis has all the polymorphisms characteristic of the transfected type 1 cosmid DNA and none characteristic of the type 2 P3HR-1 EBV DNA. This recombinant was wild type in primary B-lymphocyte infection, growth transformation, and lytic replication. Overall, the type 1 EBNA 3A gene was incorporated into 26% of the transformation marker-rescued recombinants, a frequency which was considerably higher than that observed in previous experiments with two-cosmid EBV DNA cotransfections into P3HR-1 cells (B. Tomkinson and E. Kieff, J. Virol. 66:780-789, 1992). Of the recombinants which had incorporated the

The Epstein-Barr virus lytic protein BZLF1 as a candidate target antigen for vaccine development1

PubMed Central

Hartlage, Alex S.; Liu, Tom; Patton, John T.; Garman, Sabrina L.; Zhang, Xiaoli; Kurt, Habibe; Lozanski, Gerard; Lustberg, Mark E.; Caligiuri, Michael A.; Baiocchi, Robert A.

2015-01-01

The Epstein-Barr virus (EBV) is an oncogenic, γ-herpesvirus associated with a broad spectrum of disease. While most immune-competent individuals can effectivley develop efficient adaptive immune responses to EBV, immunocompromised individuals are at serious risk for developing life threatening diseases such as Hodgkin’s lymphoma and post-transplant lymphoproliferative disorder (PTLD). Given the significant morbidity associated with EBV infection in high-risk populations, there is a need to develop vaccine strategies that restore or enhance EBV-specific immune responses. Here, we identify the EBV immediate-early protein BZLF1 as a potential target antigen for vaccine development. Primary tumors from patients with PTLD and a chimeric human-murine model of EBV-driven lymphoproliferative disorder (EBV-LPD) express BZLF1 protein. Pulsing human dendritic cells (DC) with recombinant BZLF1 followed by incubation with autologous mononuclear cells led to expansion of BZLF1-specific CD8(+) T cells in vitro and primed BZLF1-specific T-cell responses in vivo. In addition, vaccination of hu-PBL-SCID mice with BZLF1-transduced DCs induced specific cellular immunity and significantly prolonged survival from fatal EBV-LPD. These findings identify BZLF1 as a candidate target protein in the immunosurveillance of EBV and provide rationale for considering BZLF1 in vaccine strategies to enhance primary and recall immune responses and potentially prevent EBV-associated diseases. PMID:25735952

A recombinant modified vaccinia ankara vaccine encoding Epstein-Barr Virus (EBV) target antigens: a phase I trial in UK patients with EBV-positive cancer.

PubMed

Taylor, Graham S; Jia, Hui; Harrington, Kevin; Lee, Lip Wai; Turner, James; Ladell, Kristin; Price, David A; Tanday, Manjit; Matthews, Jen; Roberts, Claudia; Edwards, Ceri; McGuigan, Lesley; Hartley, Andrew; Wilson, Steve; Hui, Edwin P; Chan, Anthony T C; Rickinson, Alan B; Steven, Neil M

2014-10-01

Epstein-Barr virus (EBV) is associated with several cancers in which the tumor cells express EBV antigens EBNA1 and LMP2. A therapeutic vaccine comprising a recombinant vaccinia virus, MVA-EL, was designed to boost immunity to these tumor antigens. A phase I trial was conducted to demonstrate the safety and immunogenicity of MVA-EL across a range of doses. Sixteen patients in the United Kingdom (UK) with EBV-positive nasopharyngeal carcinoma (NPC) received three intradermal vaccinations of MVA-EL at 3-weekly intervals at dose levels between 5 × 10(7) and 5 × 10(8) plaque-forming units (pfu). Blood samples were taken at screening, after each vaccine cycle, and during the post-vaccination period. T-cell responses were measured using IFNγ ELISpot assays with overlapping EBNA1/LMP2 peptide mixes or HLA-matched epitope peptides. Polychromatic flow cytometry was used to characterize functionally responsive T-cell populations. Vaccination was generally well tolerated. Immunity increased after vaccination to at least one antigen in 8 of 14 patients (7/14, EBNA1; 6/14, LMP2), including recognition of epitopes that vary between EBV strains associated with different ethnic groups. Immunophenotypic analysis revealed that vaccination induced differentiation and functional diversification of responsive T-cell populations specific for EBNA1 and LMP2 within the CD4 and CD8 compartments, respectively. MVA-EL is safe and immunogenic across diverse ethnicities and thus suitable for use in trials against different EBV-positive cancers globally as well as in South-East Asia where NPC is most common. The highest dose (5 × 10(8) pfu) is recommended for investigation in current phase IB and II trials. ©2014 American Association for Cancer Research.

EBV+ and MSI Gastric Cancers Harbor High PD-L1/PD-1 Expression and High CD8+ Intratumoral Lymphocytes

PubMed Central

De Rosa, Simona; Tibiletti, Maria Grazia; Magnoli, Francesca; Vanoli, Alessandro; Sessa, Fausto; Chiaravalli, Anna Maria

2018-01-01

Both EBV+ and MSI gastric cancers (GCs) have high lymphoid infiltration which is rare in MSS/EBV− cancers. PD-L1/PD-1 interaction leads to a down-regulated immune response and it is one of the most promising targets for gastric cancer immunotherapy. PD-L1/PD-1 and CD8 expression were immunohistochemically investigated in a series of 169 FFPE GCs, including 33 EBV+, 59 MSI and 77 MSS/EBV− cases. PD-L1 membrane immunoreactivity in more than 5% of tumor cells was present in 31/169 GCs and was associated with high levels of CD8 intraepithelial lymphocytes (TILs; p < 0.001). PD-L1+ cases were mainly poorly differentiated (71%), intestinal type (85%) and high lymphoid response (HLR; 90%) tumors. PD-L1 expression was only present in EBV⁺ (46%), MSI (24%) and rare MSS/EBV− (3%) GCs with high CD8+ TILs (p < 0.001). Despite being associated with a better prognosis both in the whole series (p < 0.05) and in the MSI subset, PD-L1 is not an independent prognostic factor. PD-L1 gene amplification was detected in 3/17 cases, including 2/7 EBV+ and 1/8 MSI GC. PD-1⁺ TILs were significantly higher in EBV⁺ than MSI and MSS/EBV− cases. PD-L1/PD-1 pathway is selectively activated in HLR GCs and could be considered an emerging therapeutic target, particularly for EBV and MSI GCs. PMID:29614789

Epstein-Barr-Virus-Positive B-Cell Lymphoma of Recipient Origin Despite of the Elimination of Clonally EBV-Infected T Cells by Allogeneic Stem Cell Transplantation in a Patient with Chronic Active EBV Infection

PubMed Central

Nagasawa, Masayuki

2012-01-01

A 20-year-old patient with chronic active EBV infection (CAEBV) received peripheral blood stem cell transplantation (PBSCT) from HLA-one-locus-mismatched mother. Although EB-virus-infected T cells were eliminated after PBSCT, she developed EB-virus-positive B-cell lymphoma of recipient origin in the brain. By reducing the immunosuppressive therapy, the initial lesion disappeared. However, another lesion in the opposite lateral brain appeared later and was resistant to further reduction of immunosuppressive therapy. EBV-DNA was persistently negative after PBSCT in the peripheral blood. This case is suggestive in management of EBV reactivation after SCT and understanding alloimmune response to EBV. PMID:23213608

N6-methyladenosine modification and the YTHDF2 reader protein play cell type specific roles in lytic viral gene expression during Kaposi's sarcoma-associated herpesvirus infection

PubMed Central

Dominissini, Dan; He, Chuan

2018-01-01

Methylation at the N6 position of adenosine (m6A) is a highly prevalent and reversible modification within eukaryotic mRNAs that has been linked to many stages of RNA processing and fate. Recent studies suggest that m6A deposition and proteins involved in the m6A pathway play a diverse set of roles in either restricting or modulating the lifecycles of select viruses. Here, we report that m6A levels are significantly increased in cells infected with the oncogenic human DNA virus Kaposi’s sarcoma-associated herpesvirus (KSHV). Transcriptome-wide m6A-sequencing of the KSHV-positive renal carcinoma cell line iSLK.219 during lytic reactivation revealed the presence of m6A across multiple kinetic classes of viral transcripts, and a concomitant decrease in m6A levels across much of the host transcriptome. However, we found that depletion of the m6A machinery had differential pro- and anti-viral impacts on viral gene expression depending on the cell-type analyzed. In iSLK.219 and iSLK.BAC16 cells the pathway functioned in a pro-viral manner, as depletion of the m6A writer METTL3 and the reader YTHDF2 significantly impaired virion production. In iSLK.219 cells the defect was linked to their roles in the post-transcriptional accumulation of the major viral lytic transactivator ORF50, which is m6A modified. In contrast, although the ORF50 mRNA was also m6A modified in KSHV infected B cells, ORF50 protein expression was instead increased upon depletion of METTL3, or, to a lesser extent, YTHDF2. These results highlight that the m6A pathway is centrally involved in regulating KSHV gene expression, and underscore how the outcome of this dynamically regulated modification can vary significantly between cell types. PMID:29659627

Chronic active EBV infection: the experience of the Samsung Medical Center in South Korea.

PubMed

Lee, Tae-Hee; Ko, Young-Hyeh

Chronic active EBV infection (CAEBV) of T-cell or NK-cell type is an EBV+ polyclonal, oligoclonal or often monoclonal lymphoproliferative disorder (LPD) recognized as representing the spectrum of EBV-associated T-cell and NK-cell LPD with different clinical presentations; one systemic and two cutaneous disorders including hydroa vacciniforme-like T-cell LPD and mosquito bite hypersensitivity. The systemic form of the disease is characterized by fever, persistent hepatitis, hepatosplenomegaly and lymphadenopathy, which shows varying degrees of clinical severity depending on the immune response of the host and the EBV viral load. We described the clinicopathological findings of two children with CAEBV with a brief review of the literature. Recognition of the disease is important for adequate management of the patient. EBV analysis should be included in the principal diagnostic tests for febrile children. Copyright © 2015 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.

Regulatory network analysis of Epstein-Barr virus identifies functional modules and hub genes involved in infectious mononucleosis.

PubMed

Poorebrahim, Mansour; Salarian, Ali; Najafi, Saeideh; Abazari, Mohammad Foad; Aleagha, Maryam Nouri; Dadras, Mohammad Nasr; Jazayeri, Seyed Mohammad; Ataei, Atousa; Poortahmasebi, Vahdat

2017-05-01

Epstein-Barr virus (EBV) is the most common cause of infectious mononucleosis (IM) and establishes lifetime infection associated with a variety of cancers and autoimmune diseases. The aim of this study was to develop an integrative gene regulatory network (GRN) approach and overlying gene expression data to identify the representative subnetworks for IM and EBV latent infection (LI). After identifying differentially expressed genes (DEGs) in both IM and LI gene expression profiles, functional annotations were applied using gene ontology (GO) and BiNGO tools, and construction of GRNs, topological analysis and identification of modules were carried out using several plugins of Cytoscape. In parallel, a human-EBV GRN was generated using the Hu-Vir database for further analyses. Our analysis revealed that the majority of DEGs in both IM and LI were involved in cell-cycle and DNA repair processes. However, these genes showed a significant negative correlation in the IM and LI states. Furthermore, cyclin-dependent kinase 2 (CDK2) - a hub gene with the highest centrality score - appeared to be the key player in cell cycle regulation in IM disease. The most significant functional modules in the IM and LI states were involved in the regulation of the cell cycle and apoptosis, respectively. Human-EBV network analysis revealed several direct targets of EBV proteins during IM disease. Our study provides an important first report on the response to IM/LI EBV infection in humans. An important aspect of our data was the upregulation of genes associated with cell cycle progression and proliferation.

Characterization of a Bacteriophage-Induced, Host-Specific Lytic Enzyme from Lysates of Bacillus stearothermophilus Infected with Bacteriophage TP-8

PubMed Central

Brehm, Sylvia P.; Welker, N. E.

1974-01-01

Phage TP-8 lysates of Bacillus stearothermophilus 4S or 4S(8) contain lytic activity exhibiting two pH optima, one at pH 6.5 and the other at pH 7.5. Using a variety of fractionation procedures, the two lytic activities could not be separated. At pH 7.5 the lytic enzyme is an endopeptidase which hydrolyzes the l-alanyl-d-glutamyl linkage in the peptide subunits of the cell wall peptidoglycan and at pH 6.5 it exhibits N-acetylmuramidase activity. Endopeptidase activity is inhibited by NaCl and neither lytic activity was significantly affected by divalent cations or ethylenediaminetetraacetic acid. Crude lysates contain 2.5 to 3.0 times more endopeptidase activity than N-acetylmuramidase activity. The ratio of the two lytic activities (endopeptidase/N-acetylmuramidase) changes to 1.3 to 1.7 during the course of purification, to 1.0 after isoelectric focusing, and 3.9 and 6.00 after exposure for 2 h at 60 and 65 C, respectively. We conclude that the two lytic activities may be associated with a single protein or a lytic enzyme complex composed of two enzymes. Lytic activity at pH 7.5 is more effective in solubilizing cells or cell walls than the lytic activity at pH 6.5. LiCl extracts of 4S and 4S(8) cells contain lytic activity exhibiting endopeptidase activity at pH 7.5 and N-acetylmuramidase activity at pH 6.5. Lytic activity in these LiCl extracts also has a number of other properties in common with those in lysates of phage TP-8. We proposed that the lytic enzyme(s) are not coded for by the phage genome but are part of the host autolytic system. PMID:4218232

Space Flight-Induced Reactivation of Latent Epstein-Barr Virus

NASA Technical Reports Server (NTRS)

Stowe, Raymond P.; Barrett, Alan D. T.; Pierson, Duane L.

2001-01-01

Reactivation of latent Epstein-Barr virus (EBV) may be an important threat to crew health during extended space missions. Decreased cellular immune function has been reported both during and after space flight. Preliminary studies have demonstrated increased EBV shedding in saliva as well as increased antibody titers to EBV lytic proteins. We hypothesize that the combined effects of microgravity along with associated physical and psychological stress will decrease EBV-specific T-cell immunity and reactivate latent EBV in infected B-lymphocytes. If increased virus production and clonal expansion of infected B-lymphocytes are detected, then pharmacological measures can be developed and instituted prior to onset of overt clinical disease. More importantly, we will begin to understand the basic mechanisms involved in stress-induced reactivation of EBV in circulating B-lymphocytes.

Evidence of shared Epstein-Barr viral isolates between sexual partners, and low level EBV in genital secretions.

PubMed

Thomas, Ranjit; Macsween, Karen F; McAulay, Karen; Clutterbuck, Daniel; Anderson, Richard; Reid, Stuart; Higgins, Craig D; Swerdlow, Anthony J; Harrison, Nadine; Williams, Hilary; Crawford, Dorothy H

2006-09-01

Epstein-Barr virus is present in the saliva of most persistently infected individuals and is generally thought to be spread by close oral contact. However, there are now several reports of EBV in genital secretions, suggesting the possibility of sexual transmission between adults. The present study was undertaken to investigate the risk of sexual transmission of EBV. PCR analysis was used to examined the degree to which a group (n = 11) of patients with infectious mononucleosis (IM) shared the same viral isolates as their sexual partners, and compare this to the extent of isolate sharing among a different group (n = 18) of IM patients and their non-sexual contacts. There was significantly more sharing of EBV isolates among the IM/sexual-contact pairs than among the IM/non-sexual-contact pairs (P = 0.0012). Female cervical (n = 84), male urethral (n = 55), and semen (n = 30) samples from asymptomatic, unselected volunteers were analyzed for the presence of EBV DNA, revealing 7%, 5%, and 3% to be EBV positive, respectively. Fractionation of cervical and urethral samples into cellular and supernatant fluid components showed EBV to be mainly cell-associated. Quantitation of EBV in these samples gave levels of below 10 EBV genomes per microg of DNA. Overall the findings support the possibility that EBV could on occasions be transmitted sexually, however, the low levels detected in genital secretions compared to saliva suggest that this is not a major transmission route. The finding of small quantities of cell-associated virus suggests a latent infection; thus EBV is probably in the B lymphocyte rather than in the epithelial cell component of the secretions.

HLA-A alleles and infectious mononucleosis suggest a critical role for cytotoxic T-cell response in EBV-related Hodgkin lymphoma

PubMed Central

Hjalgrim, Henrik; Rostgaard, Klaus; Johnson, Paul C. D.; Lake, Annette; Shield, Lesley; Little, Ann-Margaret; Ekstrom-Smedby, Karin; Adami, Hans-Olov; Glimelius, Bengt; Hamilton-Dutoit, Stephen; Kane, Eleanor; Taylor, G. Malcolm; McConnachie, Alex; Ryder, Lars P.; Sundstrom, Christer; Andersen, Paal Skytt; Chang, Ellen T.; Alexander, Freda E.; Melbye, Mads; Jarrett, Ruth F.

2010-01-01

A proportion of classical Hodgkin lymphoma (HL) is believed to be causally related to infection with the ubiquitous lymphotropic EBV. The determining factors for development of EBV-related HL remain poorly understood, but likely involve immunological control of the viral infection. Accordingly, markers of the HLA class I region have been associated with risk of EBV-related HL. To study the host genetic component of EBV-related HL further, we investigated the lymphoma's association with HLA-A*01 and HLA-A*02 simultaneously in the setting of infectious mononucleosis (IM), a risk factor for EBV-related HL, in a case-series analysis including 278 EBV-related and 656 EBV-unrelated cases of HL. By logistic regression, HLA-A*01 alleles [odds ratio (OR) per allele, 2.15; 95% CI, 1.60–2.88] were associated with increased and HLA-A*02 alleles (OR per allele, 0.70; 95% CI, 0.51–0.97) with decreased risk of EBV-related HL. These allele-specific associations corresponded to nearly 10-fold variation in risk of EBV-related HL between HLA-A*01 and HLA-A*02 homozygotes. History of IM was also associated with risk of EBV-related HL (OR, 3.40; 95% CI, 1.74–6.66). The association between history of IM and EBV-related HL was not seen in the presence of HLA-A*02 because this allele appeared to neutralize the effect of IM on EBV-related HL risk. Our findings suggest that HLA class I-restricted EBV-specific cytotoxic T-cell responses and events in the early immune response to EBV infection in IM play critical roles in the pathogenesis of EBV-related HL. PMID:20308568

Epstein-Barr virus DNA is detected in peripheral blood mononuclear cells of EBV-seronegative infants with infectious mononucleosis-like symptoms.

PubMed

Ikuta, Kazufumi; Saiga, Kyoko; Deguchi, Masanori; Sairenji, Takeshi

2003-01-01

We demonstrated Epstein-Barr virus (EBV) DNA in peripheral blood mononuclear cells (PBMCs) from infants with infectious mononucleosis- (IM) like symptoms. Thirteen of the 17 patients did not have EBV antibodies; however, EBV DNA was detected in 8 PBMC from the 13 seronegative patients by PCR. The 4 patients were retested in 6-12 months later. Three patients were still seronegative; however EBV DNA wasnot detected. One patient seroconverted and EBV DNA could still be detected. The transcript of EBNA1 was detected in one patient, but neither EBNA2 nor LMP2A were detected in all PBMC from the 4 tested patients. Type 1 EBV DNA was detected in 5 PBMC of 7 tested patients, and type 2 EBV DNA was detected in type 1 positive PBMC of one patient as well. The IL-1 beta polymorphism that is reported to be one of the immunological factors of EBV seronegativity revealed no difference in IM-like patients. These results indicated that EBV infection occurs in EBV-seronegative IM-like infants; however, the modes of infection are clearly different from IM.

Chronic active EBV infection with features of granulomatosis with polyangiitis.

PubMed

Shimomura, Masaki; Morishita, Hideaki; Meguro, Takaaki; Seto, Shiro; Kimura, Mitsuaki; Hamazaki, Minoru; Hashimoto, Ayako; Sugiyama, Yuka; Kimura, Hiroshi

2016-07-01

Herein, we report the case of a 13-year-old boy with multiple recurrent ulcers on his legs. He developed severe sinusitis at 10 years of age and had significant weight loss (6 kg) in the 2 months prior to admission. Histology of tissue biopsied from the ulcer indicated small vessel vasculitis and granulomatous inflammation. Given that these findings met the diagnostic criteria for granulomatosis with polyangiitis (GPA), he was treated with immunosuppressive agents. Further pathology, however, indicated Epstein-Barr virus (EBV)-encoded RNA (EBER) in most lymphocytes in the same sample. The EBER-positive lymphocytes were mainly CD4-positive T cells. The EBV-DNA load in the peripheral blood was also abnormally increased (1.0 × 10(4) copies/μg DNA). Thus, the diagnosis was established as chronic active EBV infection (CAEBV). This case illustrates the necessity of careful differential diagnosis of CAEBV owing to its clinical resemblance and pathological overlap with GPA. © 2016 Japan Pediatric Society.

NCI International EBV-Gastric Cancer Consortium

Cancer.gov

A collaboration among NCI and extramural investigators, established by DCEG in 2006, that utilizes data and biospecimens from completed and ongoing case series and observational studies of gastric cancer to replicate and extend findings from previous studies hindered by small numbers of EBV-positive cases, and to stimulate multidisciplinary research in this area.

Down-regulation of increased TRAF6 expression in the peripheral mononuclear cells of patients with primary Sjögren's syndrome by an EBV-EBER1-specific synthetic single-stranded complementary DNA molecule.

PubMed

Sipka, Sándor; Zilahi, Erika; Papp, Gábor; Chen, Ji-Qing; Nagy, Andrea; Hegyi, Katalin; Kónya, József; Zeher, Margit

2017-05-01

We described earlier a simultaneously increased that the increased expression of miRNA-146a/b was accompanied by an increase in the expression of and TRAF6 and a decrease in the expression of IRAK1 genes in the peripheral mononuclear cells (PBMCs) of patients with primary Sjogren's syndrome (pSS) patients. Recently, the expression of EBV encoded. RNA (EBER) was published in the B cells of salivary glands of in pSS. In the present study, we applied an EBV-EBER1 specific synthetic single stranded complementary DNA molecule (EBV-EBER1-cDNA) to test whether any EBER1 related effect exists also in PBMCs of pSS patients. In the PBMCs of pSS patients and healthy controls, we investigated in vitro the effects of a synthetic single stranded EBV-EBER1-cDNA molecule, synthetic double-stranded (ds)RNA polyinosinic-polycytidylic acid [poly (I:C)] and polyadenylic acid potassium salt poly-adenylic acid [poly-(A)] on the expression of TRAF6 gene tested by qRTPCR. The release of interferon -α was detected by ELISA. EBV-EBER1-cDNA resulted in a significant reduction in the expression of TRAF6 in the cells of patients, but in the healthy controls not, whereas the treatments with poly (I:C) and poly-(A) could not reduce the TRAF6 over-expression. No release of EBER1 could be observed in the culture supernatants of patients with pSS. Only the treatment with poly (I:C) resulted in a significant increase of interferon -α release, and only in the heathy controls. No release of EBER1 molecules took place during the culturing of cells. EBV-EBER- cDNA acted functionally on the cells of patients only. These findings give a further evidence of the linkage between EBV and pSS, furthermore, they show the possible role of EBV-EBER1 in the induction of increased TRAF6 expression in the peripheral B cells of Sjögren's patients. © 2017 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.

The Effect of Antiretroviral Combination Treatment on Epstein-Barr Virus (EBV) Genome Load in HIV-Infected Patients

PubMed Central

Friis, Anna M. C.; Gyllensten, Katarina; Aleman, Anna; Ernberg, Ingemar; Åkerlund, Börje

2010-01-01

We evaluated the effect of combination anti-retroviral treatment (cART) on the host control of EBV infection in moderately immunosuppressed HIV-1 patients. Twenty HIV-1 infected individuals were followed for five years with repeated measurements of EBV DNA load in peripheral blood lymphocytes in relation to HIV-RNA titers and CD4+ cell counts. Individuals with optimal response, i.e. durable non-detectable HIV-RNA, showed a decline of EBV load to the level of healthy controls. Individuals with non-optimal HIV-1 control did not restore their EBV control. Long-lasting suppression of HIV-replication after early initiation of cART is a prerequisite for re-establishing the immune control of EBV. PMID:21994658

EGCG debilitates the persistence of EBV latency by reducing the DNA binding potency of nuclear antigen 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Ya-Lin; Tsai, Hsing-Lyn; Peng, Chih-Wen, E-mail: pengcw@mail.tcu.edu.tw

Highlights: Black-Right-Pointing-Pointer Two cell-based reporter platforms were established for screening of EBNA1 inhibitors. Black-Right-Pointing-Pointer EGCG acts as an inhibitor to block EBNA1 binding with the cognate oriP sequence. Black-Right-Pointing-Pointer EGCG debilitates EBNA1-dependent transcription enhancement and episome maintenance. Black-Right-Pointing-Pointer EGCG impairs persistence of EBV latency. Black-Right-Pointing-Pointer EGCG is a potent anti-EBV agent for targeting the latent cascade of EBV. -- Abstract: Because the expression of EBNA1 is prevalent in all EBV-associated tumors, it has become one of the most attractive drug targets for the discovery of anti-EBV compounds. In a cell-based reporter system, EBNA1 consistently upregulated the transcription of an oriP-Lucmore » mini-EBV episome by 6- to 8-fold. The treatment of cells with 50 {mu}M EGCG effectively blocked the binding of EBNA1 to oriP-DNA both in vivo and in vitro, which led to the abrogation of EBNA1-dependent episome maintenance and transcriptional enhancement. Importantly, the anti-EBNA1 effects caused by EGCG ultimately impaired the persistence of EBV latent infection. Our data suggest that the inhibition of EBNA1 activity by EGCG could be a promising starting point for the development of new protocols for anti-EBV therapy.« less

A phase I-II trial to examine the toxicity of CMV- and EBV-specific cytotoxic T lymphocytes when used for prophylaxis against EBV and CMV disease in recipients of CD34-selected/T cell-depleted stem cell transplants.

PubMed

Lucas, K G; Sun, Q; Burton, R L; Tilden, A; Vaughan, W P; Carabasi, M; Salzman, D; Ship, A

2000-07-01

Epstein-Barr virus (EBV)-induced lymphoproliferative disease and cytomegalovirus (CMV) infection are major causes of morbidity and mortality in individuals with compromised cellular immunity. Although anti-viral pharmacological agents exist, severe side effects such as myelosuppression often limit the application of these medications. Infusion of ex vivo-expanded, virus-specific cytotoxic T-lymphocytes (CTL) has been proven to be safe and efficacious for the prophylaxis and treatment of EBV and CMV complications. While EBV-specific CTL can be readily and reliably produced with EBV-immortalized B-lymphoblastoid cell lines (BLCL) as stimulators, current protocols for CMV-specific CTL, which use CMV-infected fibroblasts as stimulators, may be associated with alloreactivity and the need for cloning, as well as the potential for exposure to human blood-born infectious agents. Our laboratory has developed a novel system to generate EBV/CMV-bi-specific CTL by co-culturing PBMC with autologous BLCL expressing a CMV protein pp65 (BLCLpp65) (Sun et al., 1999). pp65, an immunodominant CMV antigen, is transduced into BLCL by a recombinant retrovirus MSCVpp65. While low in alloreactivity, BLCLpp65-stimulated CTL are cytolytic to autologous cells infected with EBV or CMV, and this cytotoxicity is mediated by polyclonal, CD8+, MHC Class I-restricted T-cells. Further experiments revealed that retroviral transduction and expression of pp65 do not compromise the capacity of presenting EBV antigens, and T cells stimulated by BLCLpp65 recognize clinical strains of CMV (Sun et al., 2000). These data indicated that BLCLpp65 could substitute for BLCL as antigen presenting cells in adoptive immunotherapy against EBV-LPD, with the benefit of providing protection against CMV reactivation. This protocol is a Phase I/II study to examine the toxicity associated with and the immunologic effects of ex vivo simultaneously expanded EBV- and CMV-specific CTL for prophylaxis against EBV and CMV

Unique variations of Epstein-Barr virus-encoded BARF1 gene in nasopharyngeal carcinoma biopsies.

PubMed

Wang, Yun; Wang, Xiao-Feng; Sun, Zhi-Fu; Luo, Bing

2012-06-01

The Epstein-Barr virus (EBV) BamHI-A rightward frame 1 (BARF1) gene is frequently expressed in EBV-associated epithelial malignancies and involves in oncogenicity and immunomodulation. To characterize the variations of BARF1 gene in different populations, the sequences of BARF1 gene in Northern Chinese nasopharyngeal carcinoma (NPC), EBV-associated gastric carcinoma (EBVaGC) and healthy donors were analyzed. The correlation of BARF1 variation with polymorphisms of BamHI F fragment (type F and f variants) and EBV-coded viral interleukin-10 (vIL-10) gene (B95-8 and SPM patterns) was also explored. Two major subtypes of BARF1 gene, designated as B95-8 and V29A, were identified. B95-8 subtype had identical amino acid sequence to B95-8 and was the dominant subtype among the EBV isolates from Northern China. V29A subtype, with one consistent amino acid change at residue 29 (V→A) and several nucleotide changes, showed higher frequency in NPC cases (25.3%, 20/79) than in EBVaGC cases (0/45) or healthy donors (4.3%, 2/46) (NPC vs. EBVaGC: P=0.0001; NPC vs. healthy donor: P=0.004). A preferential linkage between BamHI F and BARF1/vIL-10 polymorphisms was found. Type f isolates was specially correlated with the V29A/SPM genotype in NPC isolates and type f/V29A/SPM was preferentially found in NPC. BARF1/c-fms homology domain, transforming domain and cytotoxic T lymphocyte (CTL) epitopes of BARF1 were highly conserved in most isolates, suggesting the important role of BARF1 in virus infection and the potential usefulness in EBV-targeting immunotherapy of EBV-associated tumors. The relatively higher prevalence of type f/V29A/SPM strains in NPC may also suggest the association between these variations in multiple viral genes and NPC. Copyright © 2012 Elsevier B.V. All rights reserved.

Genetic characterization of ØVC8 lytic phage for Vibrio cholerae O1.

PubMed

Solís-Sánchez, Alejandro; Hernández-Chiñas, Ulises; Navarro-Ocaña, Armando; De la Mora, Javier; Xicohtencatl-Cortes, Juan; Eslava-Campos, Carlos

2016-03-22

Epidemics and pandemics of cholera, a diarrheal disease, are attributed to Vibrio cholera serogroups O1 and O139. In recent years, specific lytic phages of V. cholera have been proposed to be important factors in the cyclic occurrence of cholera in endemic areas. However, the role and potential participation of lytic phages during long interepidemic periods of cholera in non-endemic regions have not yet been described. The purpose of this study was to isolate and characterize specific lytic phages of V. cholera O1 strains. Sixteen phages were isolated from wastewater samples collected at the Endhó Dam in Hidalgo State, Mexico, concentrated with PEG/NaCl, and purified by density gradient. The lytic activity of the purified phages was tested using different V. cholerae O1 and O139 strains. Phage morphology was visualized by transmission electron microscopy (TEM), and phage genome sequencing was performed using the Genome Analyzer IIx System. Genome assembly and bioinformatics analysis were performed using a set of high-throughput programs. Phage structural proteins were analyzed by mass spectrometry. Sixteen phages with lytic and lysogenic activity were isolated; only phage ØVC8 showed specific lytic activity against V. cholerae O1 strains. TEM images of ØVC8 revealed a phage with a short tail and an isometric head. The ØVC8 genome comprises linear double-stranded DNA of 39,422 bp with 50.8 % G + C. Of the 48 annotated ORFs, 16 exhibit homology with sequences of known function and several conserved domains. Bioinformatics analysis showed multiple conserved domains, including an Ig domain, suggesting that ØVC8 might adhere to different mucus substrates such as the human intestinal epithelium. The results suggest that ØVC8 genome utilize the "single-stranded cohesive ends" packaging strategy of the lambda-like group. The two structural proteins sequenced and analyzed are proteins of known function. ØVC8 is a lytic phage with specific activity against V. cholerae

AtlA functions as a peptidoglycan lytic transglycosylase in the Neisseria gonorrhoeae type IV secretion system.

PubMed

Kohler, Petra L; Hamilton, Holly L; Cloud-Hansen, Karen; Dillard, Joseph P

2007-08-01

Type IV secretion systems require peptidoglycan lytic transglycosylases for efficient secretion, but the function of these enzymes is not clear. The type IV secretion system gene cluster of Neisseria gonorrhoeae encodes two peptidoglycan transglycosylase homologues. One, LtgX, is similar to peptidoglycan transglycosylases from other type IV secretion systems. The other, AtlA, is similar to endolysins from bacteriophages and is not similar to any described type IV secretion component. We characterized the enzymatic function of AtlA in order to examine its role in the type IV secretion system. Purified AtlA was found to degrade macromolecular peptidoglycan and to produce 1,6-anhydro peptidoglycan monomers, characteristic of lytic transglycosylase activity. We found that AtlA can functionally replace the lambda endolysin to lyse Escherichia coli. In contrast, a sensitive measure of lysis demonstrated that AtlA does not lyse gonococci expressing it or gonococci cocultured with an AtlA-expressing strain. The gonococcal type IV secretion system secretes DNA during growth. A deletion of ltgX or a substitution in the putative active site of AtlA severely decreased DNA secretion. These results indicate that AtlA and LtgX are actively involved in type IV secretion and that AtlA is not involved in lysis of gonococci to release DNA. This is the first demonstration that a type IV secretion peptidoglycanase has lytic transglycosylase activity. These data show that AtlA plays a role in type IV secretion of DNA that requires peptidoglycan breakdown without cell lysis.

Temperate and lytic bacteriophages programmed to sensitize and kill antibiotic-resistant bacteria

PubMed Central

Yosef, Ido; Manor, Miriam; Kiro, Ruth

2015-01-01

The increasing threat of pathogen resistance to antibiotics requires the development of novel antimicrobial strategies. Here we present a proof of concept for a genetic strategy that aims to sensitize bacteria to antibiotics and selectively kill antibiotic-resistant bacteria. We use temperate phages to deliver a functional clustered regularly interspaced short palindromic repeats (CRISPR)–CRISPR-associated (Cas) system into the genome of antibiotic-resistant bacteria. The delivered CRISPR-Cas system destroys both antibiotic resistance-conferring plasmids and genetically modified lytic phages. This linkage between antibiotic sensitization and protection from lytic phages is a key feature of the strategy. It allows programming of lytic phages to kill only antibiotic-resistant bacteria while protecting antibiotic-sensitized bacteria. Phages designed according to this strategy may be used on hospital surfaces and hand sanitizers to facilitate replacement of antibiotic-resistant pathogens with sensitive ones. PMID:26060300

Temperate and lytic bacteriophages programmed to sensitize and kill antibiotic-resistant bacteria.

PubMed

Yosef, Ido; Manor, Miriam; Kiro, Ruth; Qimron, Udi

2015-06-09

The increasing threat of pathogen resistance to antibiotics requires the development of novel antimicrobial strategies. Here we present a proof of concept for a genetic strategy that aims to sensitize bacteria to antibiotics and selectively kill antibiotic-resistant bacteria. We use temperate phages to deliver a functional clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) system into the genome of antibiotic-resistant bacteria. The delivered CRISPR-Cas system destroys both antibiotic resistance-conferring plasmids and genetically modified lytic phages. This linkage between antibiotic sensitization and protection from lytic phages is a key feature of the strategy. It allows programming of lytic phages to kill only antibiotic-resistant bacteria while protecting antibiotic-sensitized bacteria. Phages designed according to this strategy may be used on hospital surfaces and hand sanitizers to facilitate replacement of antibiotic-resistant pathogens with sensitive ones.

Glutathione diminishes Dibutyltin- and tributyltin-induced loss of lytic function in human natural killer cells

PubMed Central

Powell, Jeralyn J.; Davis, McLisa V.; Whalen, Margaret M.

2008-01-01

This study investigated whether reduced glutathione (GSH) was able to alter the negative effects of tributyltin (TBT) or dibutyltin (DBT) on the lytic function of human natural killer (NK) cells. NK cells are an intital immune defense against the development of tumors or viral infections. TBT and DBT are widespread environmental contaminants, due to their various industrial applications. Both TBT and DBT have been shown to decrease the ability of NK cells to lyse tumor cells (lytic function). The results indicated that the presence of GSH during exposure of NK cells to TBT or DBT diminished the negative effect of the BT on the lytic function of NK cells. This suggests that interaction TBT and DBT with functionally relevant sulfhydryl groups in NK cells may be part of the mechanism by which they decrease NK lytic function. PMID:18821099

Glutathione diminishes tributyltin- and dibutyltin-induced loss of lytic function in human natural killer cells.

PubMed

Powell, Jeralyn J; Davis, McLisa V; Whalen, Margaret M

2009-01-01

This study investigated whether reduced glutathione (GSH) was able to alter the negative effects of tributyltin (TBT) or dibutyltin (DBT) on the lytic function of human natural killer (NK) cells. NK cells are an initial immune defense against the development of tumors or viral infections. TBT and DBT are widespread environmental contaminants, due to their various industrial applications. Both TBT and DBT have been shown to decrease the ability of NK cells to lyse tumor cells (lytic function). The results indicated that the presence of GSH during the exposure of NK cells to TBT or DBT diminished the negative effect of the butyltin on the lytic function of NK cells. This suggests that the interaction of TBT and DBT with functionally relevant sulfhydryl groups in NK cells may be part of the mechanism by which they decrease NK lytic function.

L-Asparaginase monotherapy for EBV-positive T/NK lymphoproliferative diseases: A pilot Study.

PubMed

Jinta, Minako; Imadome, Ken-Ichi; Komatsu, Honami; Yoshimori, Mayumi; Kurata, Morito; Fujiwara, Shigeyoshi; Miura, Osamu; Arai, Ayako

2015-03-30

We investigated the effects of L-asparaginase (L-asp) on Epstein-Barr virus (EBV)-positive T/NK lymphoproliferative diseases (EBV-T/ NK-LPDs). Seven doses of L-asp (6,000 U/m2) were administered intravenously, with one dose administered on every alternate day. Five consecutive patients were enrolled. Three patients completed the treatment. The clinical symptoms resolved in 1 patient who started the administration 8 months after the onset, being the earliest among the 5 patients. Her EBV-DNA level in whole blood markedly decreased to 0.08 times of that before treatment, and the level in plasma became undetectable. In the other 2 patients whose administration was started 3 and 3.5 years after the onset, however, a remarkable improvement was not detected. Treatment was discontinued in 2 patients because of disease progression or idiopathic dystonia. The mRNA levels of asparagine synthetase in EBV-infected cells were examined. The level from the patient who responded to L-asp treatment was low, but it did not correlate with the effects in the other patients. Liver dysfunction (grades 2 and 3) was observed in 2 patients and neutropenia (grade 3) was noted in 1 patient. In conclusion, the effect of L-asp as monotherapy in EBV-T/NK-LPDs is limited, and early treatment initiation might be effective.

Acute hepatitis: a rare complication of Epstein-Barr virus (EBV) infection.

PubMed

Uluğ, Mehmet; Celen, Mustafa Kemal; Ayaz, Celal; Geyik, Mehmet Faruk; Hoşoğlu, Salih

2010-10-28

Infectious Mononucleosis (IM), a benign lymphoproliferative disease, is the best known clinical syndrome caused by Epstein-Barr Virus (EBV). It usually resolves over a period of weeks or months without sequelae but may occasionally be complicated by a wide variety of neurologic, hematologic, hepatic, respiratory, and psychological complications. In this report we describe a patient with acute hepatitis following EBV-IM in a previously healthy woman. A 26-year-old woman who presented with fever, generalized weakness, nausea, sore throat, yellowing of skin, and a generalized skin rash was admitted to our clinic. Tonsillar enlargement, pharyngeal erythema, palatal petechiae, lymphadenopathy, and jaundice were noted. Significant atypical lymphocytes ( > 10%) were seen on the peripheral blood smear. Liver function tests such as ALT: 303 U/L, AST: 172 U/L, ALP: 193 U/L and total bilirubin: 7.3 mg/dl were elevated. Serological tests for EBV infection were consistent with acute infection (EBV virus capsid antigen was reactive with IgM and IgG antibodies). The Monospot test was also positive. On the seventh day, liver function tests and bilirubin had risen to peak level and platelets were decreased. The patient was managed supportively and her critical condition improved and was finally stabilized. Although the prognosis for IM is very favorable, a variety of acute complications may occur.

Comprehensive assessment of peripheral blood TCRβ repertoire in infectious mononucleosis and chronic active EBV infection patients.

PubMed

Liu, Shenglin; Zhang, Qian; Huang, Dongli; Zhang, Wenli; Zhong, Fengluan; Feng, Jia; Chen, Xueru; Meng, Qingxiang; Chen, Xiaofan; Zhang, Wei; Zhang, Hongyu

2017-04-01

Epstein-Barr virus (EBV) primary infection is usually asymptomatic, but it sometimes progresses to infectious mononucleosis (IM). Occasionally, some people develop chronic active EBV infection (CAEBV) with underlying immunodeficiency, which belongs to a continuous spectrum of EBV-associated lymphoproliferative disorders (EBV + LPD) with heterogeneous clinical presentations and high mortality. It has been well established that T cell-mediated immune response plays a critical role in the disease evolution of EBV infection. Recently, high-throughput sequencing of the hypervariable complementarity-determining region 3 (CDR3) segments of the T cell receptor (T cell receptor β (TCRβ)) has emerged as a sensitive approach to assess the T cell repertoire. In this study, we fully characterized the diversity of peripheral blood TCRβ repertoire in IM (n = 6) and CAEBV patients (n = 5) and EBV-seropositive controls (n = 5). Compared with the healthy EBV-seropositive controls, both IM and CAEBV patients demonstrate a significant decrease in peripheral blood TCRβ repertoire diversity, basically, including narrowed repertoire breadth, highly expanded clones, and skewed CDR3 length distribution. However, there is no significant difference between IM and CAEBV patients. Furthermore, we observed some disease-related preferences in TRBV/TRBJ usage and combinations, as well as lots of T cell clones shared by different groups (unique or overlapped) involved in public T cell responses, which provide more detailed insights into the divergent disease evolution.

Unusual MRI findings in an immunocompetent patient with EBV encephalitis: a case report

PubMed Central

2011-01-01

Blackground It is well-known that Epstein-Barr virus (EBV) can affect the central nervous system (CNS). Case presentation Herein the authors report unusual timely Magnetic Resonance Imaging (MRI) brain scan findings in an immunocompetent patient with EBV encephalitis. Diffusion weighted MRI sequence performed during the acute phase of the disease was normal, whereas the Fast Relaxation Fast Spin Echo T2 image showed diffuse signal intensity changes in white matter. The enhancement pattern suggested an inflammatory response restricted to the brain microcirculation. Acyclovir and corticosteroid therapy was administered. After three weeks, all signal intensities returned to normal and the patient showed clinical recovery. Conclusion This report demonstrates that EBV in an immunocompetent adult can present with diffuse, reversible brain white matter involvement in the acute phase of mononucleosis. Moreover, our case suggests that a negative DWI sequence is associated with a favorable improvement in severe EBV CNS infection. More extensive studies are needed to assess what other instrumental data can help to distinguish viral lesions from other causes in the acute phase of disease. PMID:21435249

Epstein-Barr virus is present in the brain of most cases of multiple sclerosis and may engage more than just B cells

PubMed Central

Hassani, Asma; Corboy, John R.; Al-Salam, Suhail

2018-01-01

Multiple sclerosis (MS) is a chronic neuroinflammatory condition of the central nervous system (CNS). It is a major cause of neurological disability in young adults, particularly women. What triggers the destruction of myelin sheaths covering nerve fibres is unknown. Both genetic and infectious agents have been implicated. Of the infectious agents, Epstein-Barr virus (EBV), a common herpesvirus, has the strongest epidemiological and serological evidence. However, the presence of EBV in the CNS and demonstration of the underlying mechanism(s) linking EBV to the pathogenesis of MS remain to be elucidated. We aimed at understanding the contribution of EBV infection in the pathology of MS. We examined 1055 specimens (440 DNA samples and 615 brain tissues) from 101 MS and 21 non-MS cases for the presence of EBV using PCR and EBER-in situ hybridization (EBER-ISH). EBV was detected by PCR and/or EBER-ISH in 91/101 (90%) of MS cases compared to only 5/21 (24%) of non-MS cases with other neuropathologies. None of the samples were PCR positive for other common herpesviruses (HSV-1, CMV, HHV-6). By quantitative PCR, EBV viral load in MS brain was mainly low to moderate in most cases. However, in 18/101 (18%) of MS cases, widespread but scattered presence of EBV infected cells was noted in the affected tissues by EBER-ISH. Immunohistochemical analysis of EBV gene expression in the 18 heavily infected cases, revealed that the EBV latent protein EBNA1, and to a lesser extent the early lytic protein BZLF1 were expressed. Furthermore, using double-staining we show for the first time that astrocytes and microglia, in addition to B-cells can also be infected. To the best of our knowledge, this is the most comprehensive study demonstrating that EBV is present and transcriptionally active in the brain of most cases of MS and supports a role for the virus in MS pathogenesis. Further studies are required to address the mechanism of EBV involvement in MS pathology. PMID:29394264

Detection of Epstein-Barr virus genome and latent infection gene expression in normal epithelia, epithelial dysplasia, and squamous cell carcinoma of the oral cavity.

PubMed

Kikuchi, Kentaro; Noguchi, Yoshihiro; de Rivera, Michelle Wendoline Garcia-Niño; Hoshino, Miyako; Sakashita, Hideaki; Yamada, Tsutomu; Inoue, Harumi; Miyazaki, Yuji; Nozaki, Tadashige; González-López, Blanca Silvia; Ide, Fumio; Kusama, Kaoru

2016-03-01

A relationship between Epstein-Barr virus (EBV) infection and cancer of lymphoid and epithelial tissues such as Burkitt's lymphoma, Hodgkin's disease, nasopharyngeal carcinoma (NPC), gastric carcinoma, and oral cancer has been reported. EBV is transmitted orally and infects B cells and epithelial cells. However, it has remained uncertain whether EBV plays a role in carcinogenesis of oral mucosal tissue. In the present study, we detected the EBV genome and latent EBV gene expression in normal mucosal epithelia, epithelial dysplasia, and oral squamous cell carcinoma (OSCC) to clarify whether EBV is involved in carcinogenesis of the oral cavity. We examined 333 formalin-fixed, paraffin-embedded tissue samples (morphologically normal oral mucosa 30 samples, gingivitis 32, tonsillitis 17, oral epithelial dysplasia 83, OSCC 150, and NPC 21). EBV latent infection genes (EBNA-2, LMP-1) were detected not only in OSCC (50.2 %, 10.7 %) but also in severe epithelial dysplasia (66.7 %, 44.4 %), mild to moderate epithelial dysplasia (43.1 %, 18.5 %), gingivitis (78.1 %, 21.9 %), and normal mucosa (83.3 %, 23.3 %). Furthermore, the intensity of EBV latent infection gene expression (EBER, LMP-1) was significantly higher in severe epithelial dysplasia (94.4 %, 72.2 %) than in OSCC (34.7 %, 38.7 %). These results suggest that EBV latent infection genes and their increased expression in severe epithelial dysplasia might play an important role in the dysplasia-carcinoma sequence in the oral cavity.

Successful Immunosuppressive Therapy for Severe Infectious Mononucleosis in a Patient with Clonal Proliferation of EBV-infected CD8-positive Cells.

PubMed

Hosoi, Hiroki; Sonoki, Takashi; Murata, Shogo; Mushino, Toshiki; Kuriyama, Kodai; Nishikawa, Akinori; Hanaoka, Nobuyoshi; Ohshima, Koichi; Imadome, Ken-Ichi; Nakakuma, Hideki

2015-01-01

A 30-year-old woman was diagnosed with severe infectious mononucleosis (IM). The Epstein-Barr virus (EBV) had infected both CD19- and CD8-positive cells, and clonal proliferation of EBV-infected cells and T-cells was detected. Although we suspected malignant lymphoma, her condition improved following immunosuppressive therapy. A similar case was recently reported; therefore, this case is the second case of IM with EBV-infected CD8-positive cells and clonal proliferation of EBV-infected cells. Our results demonstrate that the clonal proliferation of EBV-infected cells is not always an indication for chemotherapy in the primary infection phase and that monitoring the EBV viral load is useful for therapeutic decision-making.

Successful control of Epstein-Barr virus (EBV)-infected cells by allogeneic nonmyeloablative stem cell transplantation in a patient with the lethal form of chronic active EBV infection.

PubMed

Uehara, Taeko; Nakaseko, Chiaki; Hara, Satoru; Harima, Akane; Ejiri, Megumi; Yokota, Akira; Saito, Yasushi; Nishimura, Miki

2004-08-01

Chronic active Epstein-Barr virus infection (CAEBV) is a heterogeneous EBV-related disorder, ranging from mild/moderate forms to rapidly lethal disorders. The lethal form of CAEBV is characterized by multiple organ failure, hemophagocytic syndrome, and development of lymphomas. Allogeneic stem cell transplantation is considered as the only potentially curative treatment for the lethal form of CAEBV, but it is not always desirable because of the high incidence of regimen-related toxicities. A 17-year-old female with CAEBV, who was refractory to conventional therapies and considered to be unable to receive a myeloablative regimen because of multiple organ dysfunction, underwent allogeneic nonmyeloablative stem cell transplantation (allo-NST) before developing a hematological malignancy. She has been well without any signs of CAEBV for 27 months after allo-NST, and we confirmed that specific cytotoxic T lymphocyte activity against EBV was reconstituted. This outcome suggests that allo-NST can control CAEBV by reconstituting the host immunity against EBV. Copyright 2004 Wiley-Liss, Inc.

Adenovirus Death Protein (ADP) Is Required for Lytic Infection of Human Lymphocytes

PubMed Central

Murali, V. K.; Ornelles, D. A.; Gooding, L. R.; Wilms, H. T.; Huang, W.; Tollefson, A. E.; Wold, W. S. M.

2014-01-01

The adenovirus death protein (ADP) is expressed at late times during a lytic infection of species C adenoviruses. ADP promotes the release of progeny virus by accelerating the lysis and death of the host cell. Since some human lymphocytes survive while maintaining a persistent infection with species C adenovirus, we compared ADP expression in these cells with ADP expression in lymphocytes that proceed with a lytic infection. Levels of ADP were low in KE37 and BJAB cells, which support a persistent infection. In contrast, levels of ADP mRNA and protein were higher in Jurkat cells, which proceed with a lytic infection. Epithelial cells infected with an ADP-overexpressing virus died more quickly than epithelial cells infected with an ADP-deleted virus. However, KE37, and BJAB cells remained viable after infection with the ADP-overexpressing virus. Although the levels of ADP mRNA increased in KE37 and BJAB cells infected with the ADP-overexpressing virus, the fraction of cells with detectable ADP was unchanged, suggesting that the control of ADP expression differs between epithelial and lymphocytic cells. When infected with an ADP-deleted adenovirus, Jurkat cells survived and maintained viral DNA for greater than 1 month. These findings are consistent with the notion that the level of ADP expression determines whether lymphocytic cells proceed with a lytic or a persistent adenovirus infection. PMID:24198418

Activating PIK3CD mutations impair human cytotoxic lymphocyte differentiation, function and EBV immunity.

PubMed

Edwards, Emily S J; Bier, Julia; Cole, Theresa S; Wong, Melanie; Hsu, Peter; Berglund, Lucinda J; Boztug, Kaan; Lau, Anthony; Gostick, Emma; Price, David A; O'Sullivan, Michael; Meyts, Isabelle; Choo, Sharon; Gray, Paul; Holland, Steven M; Deenick, Elissa K; Uzel, Gulbu; Tangye, Stuart G

2018-05-22

Germline gain-of function (GOF) mutations in PIK3CD, encoding the catalytic p110δ subunit of phosphatidylinositol-3 kinase, result in hyperactivation of the PI3K-AKT-mTOR pathway and underlie a novel inborn error of immunity. Affected individuals exhibit perturbed humoral and cellular immunity, manifesting as recurrent infections, autoimmunity, hepatosplenomegaly, uncontrolled EBV and/or CMV infection, and an increased incidence of B-cell lymphoproliferation and/or lymphoma. Mechanisms underlying disease pathogenesis remain unknown. Understanding the cellular and molecular mechanisms underpinning inefficient surveillance of EBV-infected B cells is required to understand disease in individuals with PIK3CD GOF mutations, identify key molecules required for cell mediated immunity against EBV, and develop immunotherapeutic interventions for the treatment of this as well as other EBV-opathies. We studied the consequences of PIK3CD GOF mutations on the generation, differentiation and function of CD8 + T cells and NK cells, which are implicated in host defense against infection with herpesviruses including EBV. PIK3CD GOF total and EBV-specific CD8 + T cells were skewed towards an effector phenotype, with exaggerated expression of markers associated with premature immunosenescence/exhaustion, and increased susceptibility to re-activation induced cell death. These findings were recapitulated in a novel mouse model of PI3K GOF. NK cells in PIK3CD GOF individuals also exhibited perturbed expression of differentiation-associated molecules. Both CD8 + T cells and NK cells had reduced capacity to kill EBV-infected B cells. PIK3CD GOF B cells had increased expression of CD48, PDL-1/2 and CD70. PIK3CD GOF mutations aberrantly induce exhaustion and/or senescence and impair cytotoxicity of CD8+ T and NK cells. These defects may contribute to clinical features of affected individuals, such as impaired immunity to herpesviruses and tumor surveillance. Copyright © 2018. Published by

Broad-range lytic bacteriophages that kill Staphylococcus aureus local field strains

PubMed Central

Boncompain, Carina A.; Amadio, Ariel A.; Carrasco, Soledad; Suárez, Cristian A.

2017-01-01

Staphylococcus aureus is a very successful opportunistic pathogen capable of causing a variety of diseases ranging from mild skin infections to life-threatening sepsis, meningitis and pneumonia. Its ability to display numerous virulence mechanisms matches its skill to display resistance to several antibiotics, including β-lactams, underscoring the fact that new anti-S. aureus drugs are urgently required. In this scenario, the utilization of lytic bacteriophages that kill bacteria in a genus -or even species- specific way, has become an attractive field of study. In this report, we describe the isolation, characterization and sequencing of phages capable of killing S. aureus including methicillin resistant (MRSA) and multi-drug resistant S. aureus local strains from environmental, animal and human origin. Genome sequencing and bio-informatics analysis showed the absence of genes encoding virulence factors, toxins or antibiotic resistance determinants. Of note, there was a high similarity between our set of phages to others described in the literature such as phage K. Considering that reported phages were obtained in different continents, it seems plausible that there is a commonality of genetic features that are needed for optimum, broad host range anti-staphylococcal activity of these related phages. Importantly, the high activity and broad host range of one of our phages underscores its promising value to control the presence of S. aureus in fomites, industry and hospital environments and eventually on animal and human skin. The development of a cocktail of the reported lytic phages active against S. aureus–currently under way- is thus, a sensible strategy against this pathogen. PMID:28742812

Broad-range lytic bacteriophages that kill Staphylococcus aureus local field strains.

PubMed

Abatángelo, Virginia; Peressutti Bacci, Natalia; Boncompain, Carina A; Amadio, Ariel F; Carrasco, Soledad; Suárez, Cristian A; Morbidoni, Héctor R

2017-01-01

Staphylococcus aureus is a very successful opportunistic pathogen capable of causing a variety of diseases ranging from mild skin infections to life-threatening sepsis, meningitis and pneumonia. Its ability to display numerous virulence mechanisms matches its skill to display resistance to several antibiotics, including β-lactams, underscoring the fact that new anti-S. aureus drugs are urgently required. In this scenario, the utilization of lytic bacteriophages that kill bacteria in a genus -or even species- specific way, has become an attractive field of study. In this report, we describe the isolation, characterization and sequencing of phages capable of killing S. aureus including methicillin resistant (MRSA) and multi-drug resistant S. aureus local strains from environmental, animal and human origin. Genome sequencing and bio-informatics analysis showed the absence of genes encoding virulence factors, toxins or antibiotic resistance determinants. Of note, there was a high similarity between our set of phages to others described in the literature such as phage K. Considering that reported phages were obtained in different continents, it seems plausible that there is a commonality of genetic features that are needed for optimum, broad host range anti-staphylococcal activity of these related phages. Importantly, the high activity and broad host range of one of our phages underscores its promising value to control the presence of S. aureus in fomites, industry and hospital environments and eventually on animal and human skin. The development of a cocktail of the reported lytic phages active against S. aureus-currently under way- is thus, a sensible strategy against this pathogen.

KSHV LANA and EBV LMP1 induce the expression of UCH-L1 following viral transformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bentz, Gretchen L.; Bheda-Malge, Anjali; Wang, Ling

Ubiquitin C-terminal Hydrolase L1 (UCH-L1) has oncogenic properties and is highly expressed during malignancies. We recently documented that Epstein-Barr virus (EBV) infection induces uch-l1 expression. Here we show that Kaposi's Sarcoma-associated herpesvirus (KSHV) infection induced UCH-L1 expression, via cooperation of KSHV Latency-Associated Nuclear Antigen (LANA) and RBP-Jκ and activation of the uch-l1 promoter. UCH-L1 expression was also increased in Primary Effusion Lymphoma (PEL) cells co-infected with KSHV and EBV compared with PEL cells infected only with KSHV, suggesting EBV augments the effect of LANA on uch-l1. EBV latent membrane protein 1 (LMP1) is one of the few EBV products expressedmore » in PEL cells. Results showed that LMP1 was sufficient to induce uch-l1 expression, and co-expression of LMP1 and LANA had an additive effect on uch-l1 expression. These results indicate that viral latency products of both human γ-herpesviruses contribute to uch-l1 expression, which may contribute to the progression of lymphoid malignancies. - Highlights: • Infection of endothelial cells with KSHV induced UCH-L1 expression. • KSHV LANA is sufficient for the induction of uch-l1. • Co-infection with KSHV and EBV (observed in some PELs) results in the additive induction of uch-l1. • EBV LMP1 also induced UCH-L1 expression. • LANA- and LMP1-mediated activation of the uch-l1 promoter is in part through RBP-Jκ.« less

Two New Lytic Bacteriophages of the Myoviridae Family Against Carbapenem-Resistant Acinetobacter baumannii

PubMed Central

Zhou, Weilong; Feng, Yu; Zong, Zhiyong

2018-01-01

Two lytic bacteriophages, WCHABP1 and WCHABP12, were recovered from hospital sewage and were able to infect 9 and 12 out of 18 carbapenem-resistant Acinetobacter baumannii clinical strains, which belonged to different clones. Electron microscopy scan showed that both bacteriophages had the similar morphology as those of the Myoviridae family. Whole genomic sequencing revealed 45.4- or 45.8-kb genome with a 37.6% GC content for WCHABP1 and WCHABP12, both of which showed significant DNA sequence similarity with bacteriophages of the Ap22virus genus within the Myoviridae family. Taxonomic analysis was therefore performed following the proposal approved by the International Committee on Taxonomy of Viruses, which confirmed that WCHABP1 and WCHABP12 represented two new species of the Ap22virus genus. No tRNAs but 88 and 89 open reading frames (ORFs) were predicted for the two bacteriophages, among which 22 and 21 had known function and encoded proteins for morphogenesis, packaging, lysis, and nucleiotide metabolism. The C-terminal amino acids of the large unit of fiber tail proteins varied between the bacteriophages, which may explain their different host ranges. For most lytic bacteriophages, a set of holin and endolysin are required for lysis. However, no known holin-encoding genes were identified in WCHABP1 and WCHABP12, suggesting that they may use alternative, yet-to-be-identified, novel holins for host cell membrane lysis. To test the efficacy of the bacteriophages in protecting against A. baumannii infection, a Galleria mellonella larva model was used. Only <20% G. mellonella larvae survived at 96 h after being infected by carbapenem-resistant A. baumannii strains, from which the two bacteriophages were recovered. With the administration of WCHABP1 and WCHABP12, the survival of larvae increased to 75%, while the treatment of polymyxin B only slightly increased the survival rate to 25%. The isolation of two new lytic bacteriophages in this study could expand our

The impact of targeting repetitive BamHI-W sequences on the sensitivity and precision of EBV DNA quantification.

PubMed

Sanosyan, Armen; Fayd'herbe de Maudave, Alexis; Bollore, Karine; Zimmermann, Valérie; Foulongne, Vincent; Van de Perre, Philippe; Tuaillon, Edouard

2017-01-01

Viral load monitoring and early Epstein-Barr virus (EBV) DNA detection are essential in routine laboratory testing, especially in preemptive management of Post-transplant Lymphoproliferative Disorder. Targeting the repetitive BamHI-W sequence was shown to increase the sensitivity of EBV DNA quantification, but the variability of BamHI-W reiterations was suggested to be a source of quantification bias. We aimed to assess the extent of variability associated with BamHI-W PCR and its impact on the sensitivity of EBV DNA quantification using the 1st WHO international standard, EBV strains and clinical samples. Repetitive BamHI-W- and LMP2 single- sequences were amplified by in-house qPCRs and BXLF-1 sequence by a commercial assay (EBV R-gene™, BioMerieux). Linearity and limits of detection of in-house methods were assessed. The impact of repeated versus single target sequences on EBV DNA quantification precision was tested on B95.8 and Raji cell lines, possessing 11 and 7 copies of the BamHI-W sequence, respectively, and on clinical samples. BamHI-W qPCR demonstrated a lower limit of detection compared to LMP2 qPCR (2.33 log10 versus 3.08 log10 IU/mL; P = 0.0002). BamHI-W qPCR underestimated the EBV DNA load on Raji strain which contained fewer BamHI-W copies than the WHO standard derived from the B95.8 EBV strain (mean bias: - 0.21 log10; 95% CI, -0.54 to 0.12). Comparison of BamHI-W qPCR versus LMP2 and BXLF-1 qPCR showed an acceptable variability between EBV DNA levels in clinical samples with the mean bias being within 0.5 log10 IU/mL EBV DNA, whereas a better quantitative concordance was observed between LMP2 and BXLF-1 assays. Targeting BamHI-W resulted to a higher sensitivity compared to LMP2 but the variable reiterations of BamHI-W segment are associated with higher quantification variability. BamHI-W can be considered for clinical and therapeutic monitoring to detect an early EBV DNA and a dynamic change in viral load.

The impact of targeting repetitive BamHI-W sequences on the sensitivity and precision of EBV DNA quantification

PubMed Central

Fayd’herbe de Maudave, Alexis; Bollore, Karine; Zimmermann, Valérie; Foulongne, Vincent; Van de Perre, Philippe; Tuaillon, Edouard

2017-01-01

Background Viral load monitoring and early Epstein-Barr virus (EBV) DNA detection are essential in routine laboratory testing, especially in preemptive management of Post-transplant Lymphoproliferative Disorder. Targeting the repetitive BamHI-W sequence was shown to increase the sensitivity of EBV DNA quantification, but the variability of BamHI-W reiterations was suggested to be a source of quantification bias. We aimed to assess the extent of variability associated with BamHI-W PCR and its impact on the sensitivity of EBV DNA quantification using the 1st WHO international standard, EBV strains and clinical samples. Methods Repetitive BamHI-W- and LMP2 single- sequences were amplified by in-house qPCRs and BXLF-1 sequence by a commercial assay (EBV R-gene™, BioMerieux). Linearity and limits of detection of in-house methods were assessed. The impact of repeated versus single target sequences on EBV DNA quantification precision was tested on B95.8 and Raji cell lines, possessing 11 and 7 copies of the BamHI-W sequence, respectively, and on clinical samples. Results BamHI-W qPCR demonstrated a lower limit of detection compared to LMP2 qPCR (2.33 log10 versus 3.08 log10 IU/mL; P = 0.0002). BamHI-W qPCR underestimated the EBV DNA load on Raji strain which contained fewer BamHI-W copies than the WHO standard derived from the B95.8 EBV strain (mean bias: - 0.21 log10; 95% CI, -0.54 to 0.12). Comparison of BamHI-W qPCR versus LMP2 and BXLF-1 qPCR showed an acceptable variability between EBV DNA levels in clinical samples with the mean bias being within 0.5 log10 IU/mL EBV DNA, whereas a better quantitative concordance was observed between LMP2 and BXLF-1 assays. Conclusions Targeting BamHI-W resulted to a higher sensitivity compared to LMP2 but the variable reiterations of BamHI-W segment are associated with higher quantification variability. BamHI-W can be considered for clinical and therapeutic monitoring to detect an early EBV DNA and a dynamic change in viral load

NK cells converge lytic granules to promote cytotoxicity and prevent bystander killing

PubMed Central

Hsu, Hsiang-Ting; Viswanath, Dixita I.; Önfelt, Björn

2016-01-01

Natural killer (NK) cell activation triggers sequential cellular events leading to destruction of diseased cells. We previously identified lytic granule convergence, a dynein- and integrin signal–dependent movement of lysosome-related organelles to the microtubule-organizing center, as an early step in the cell biological process underlying NK cell cytotoxicity. Why lytic granules converge during NK cell cytotoxicity, however, remains unclear. We experimentally controlled the availability of human ligands to regulate NK cell signaling and promote granule convergence with either directed or nondirected degranulation. By the use of acoustic trap microscopy, we generated specific effector–target cell arrangements to define the impact of the two modes of degranulation. NK cells with converged granules had greater targeted and less nonspecific “bystander” killing. Additionally, NK cells in which dynein was inhibited or integrin blocked under physiological conditions demonstrated increased nondirected degranulation and bystander killing. Thus, NK cells converge lytic granules and thereby improve the efficiency of targeted killing and prevent collateral damage to neighboring healthy cells. PMID:27903610

The Role of Gammaherpesviruses in Cancer Pathogenesis

PubMed Central

Jha, Hem Chandra; Banerjee, Shuvomoy; Robertson, Erle S.

2016-01-01

Worldwide, one fifth of cancers in the population are associated with viral infections. Among them, gammaherpesvirus, specifically HHV4 (EBV) and HHV8 (KSHV), are two oncogenic viral agents associated with a large number of human malignancies. In this review, we summarize the current understanding of the molecular mechanisms related to EBV and KSHV infection and their ability to induce cellular transformation. We describe their strategies for manipulating major cellular systems through the utilization of cell cycle, apoptosis, immune modulation, epigenetic modification, and altered signal transduction pathways, including NF-kB, Notch, Wnt, MAPK, TLR, etc. We also discuss the important EBV latent antigens, namely EBNA1, EBNA2, EBNA3’s and LMP’s, which are important for targeting these major cellular pathways. KSHV infection progresses through the engagement of the activities of the major latent proteins LANA, v-FLIP and v-Cyclin, and the lytic replication and transcription activator (RTA). This review is a current, comprehensive approach that describes an in-depth understanding of gammaherpes viral encoded gene manipulation of the host system through targeting important biological processes in viral-associated cancers. PMID:26861404

Ceramides promote apoptosis for virus-infected lymphoma cells through induction of ceramide synthases and viral lytic gene expression

PubMed Central

Dai, Lu; Trillo-Tinoco, Jimena; Bai, Aiping; Chen, Yihan; Bielawski, Jacek; Del Valle, Luis; Smith, Charles D.; Ochoa, Augusto C.; Qin, Zhiqiang; Parsons, Chris

2015-01-01

Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiologic agent for several human cancers including primary effusion lymphoma (PEL), a rapidly progressive malignancy arising preferentially in immunocompromised patients. With conventional chemotherapy, PEL continues to portend high mortality, dictating the development of novel therapeutic strategies. Sphingosine kinase 2 (SphK2) represents a key gatekeeper for sphingolipid metabolism, responsible for conversion of ceramides to sphingosine-1-phosphate (S1P). We have previously demonstrated that targeting SphK2 using a novel selective inhibitor, ABC294640, leads to intracellular accumulation of ceramides and induces apoptosis for KSHV-infected PEL cells, while suppressing tumor progression in vivo. In the current study, we sought to determine whether specific ceramide/dh-ceramide species and related ceramide synthases (CerS) impact viability for KSHV-infected PEL cells during targeting of SphK2. We found that several specific ceramide and dihydro(dh)-ceramide species and their associated CerS reduce PEL survival and tumor expansion in vitro and in vivo. Moreover, we found that dhC16-Cer induces PEL apoptosis in part through activation of KSHV lytic gene expression. These data further implicate bioactive sphingolipids in regulation of PEL survival, and provide justification for future studies evaluating clinically relevant ceramide analogs or mimetics for their potential as therapeutic agents for PEL. PMID:26327294

Survival features of EBV-stabilized cells from centenarians: morpho-functional and transcriptomic analyses.

PubMed

Matarrese, Paola; Tinari, Antonella; Ascione, Barbara; Gambardella, Lucrezia; Remondini, Daniel; Salvioli, Stefano; Tenedini, Elena; Tagliafico, Enrico; Franceschi, Claudio; Malorni, Walter

2012-12-01

In the present work, we analyzed the survival features of six different Epstein-Barr virus (EBV)-stabilized lymphoid cell lines obtained from adult subjects and from subjects of more than 95 years. For the first, we found that lymphoid B cells from centenarians were more resistant to apoptosis induction and displayed a more developed lysosomal compartment, the most critical component of phagic machinery, in comparison with lymphoid B cells from adult subjects. In addition, cells from centenarians were capable of engulfing and digesting other cells, i.e., their siblings (even entire cells), whereas lymphoid cells from "control samples", i.e., from adults, did not. This behavior was improved by nutrient deprivation but, strikingly, it was unaffected by the autophagy-modulating drug, rapamycin, an autophagy inducer, and 3-methyladenine, an autophagy inhibitor. Transcriptomic analyses indicated that: (1) aspartyl proteases, (2) cell surface molecules such as integrins and cadherins, and (3) some components of cytoskeletal network could contribute to establish this survival phenotype. Also, Kyoto Encyclopedia of Genes and Genomes pathways such as Wnt signaling pathway, an essential contributor to cell migration and actin cytoskeleton remodeling, appeared as prominent. Although we cannot rule out the possibility that EBV-immortalization could play a role, since we observed this phagic behavior in cells from centenarians but not in those from adults, we hypothesize that it may represent an important survival determinant in cells from centenarians.

Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Manbok, E-mail: manbok66@dankook.ac.kr; Rahman, Masmudur M.; Cogle, Christopher R.

Epstein–Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignanciesmore » in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts. - Highlights: • Myxoma virus effectively infects and purges EBV lymphoma cells in vivo. • Oncolytic myxoma virus effectively eradicates oncogenic EBV tumorigenesis. • Ex vivo pre-treatment of myxoma virus can be effective as a preventive treatment modality for post-transplant lymphoproliferative diseases.« less

Epstein-Barr virus (EBV) in infectious mononucleosis: detection of the virus in tonsillar B lymphocytes but not in desquamated oropharyngeal epithelial cells

PubMed Central

Niedobitek, G; Agathanggelou, A; Steven, N; Young, L S

2000-01-01

Aims—Despite its well established tropism for B cells, the nature of the cellular compartment(s) mediating primary and persistent Epstein-Barr virus (EBV) infection is still a matter of controversy. In view of the association of EBV with several lymphoid and epithelial malignancies, resolution of this issue is important. Methods—Desquamated oropharyngeal epithelial cells from 10 patients with acute infectious mononucleosis and from seven chronic virus carriers were studied for evidence of EBV infection using in situ hybridisation for the detection of the small EBV encoded RNAs (EBERs) and of the viral genome. In addition, immunocytochemistry was used to detect the BZLF1 transactivator protein of EBV. Results—There was no evidence of latent or replicative EBV infection in oropharyngeal epithelial cells in any of the samples. In contrast, EBV infected B cells were readily identified in a tonsil from a patient with infectious mononucleosis. Conclusions—The results suggest that oropharyngeal epithelial cells are not a major site of EBV infection and provide further support for the notion that B cells mediate primary and persistent EBV infection. PMID:10884920

Infection of autoreactive B lymphocytes with EBV, causing chronic autoimmune diseases.

PubMed

Pender, Michael P

2003-11-01

I hypothesize that human chronic autoimmune diseases are based on infection of autoreactive B lymphocytes by Epstein-Barr virus (EBV), in the following proposed scenario. During primary infection, autoreactive B cells are infected by EBV, proliferate and become latently infected memory B cells, which are resistant to the apoptosis that occurs during normal B-cell homeostasis because they express virus-encoded anti-apoptotic molecules. Genetic susceptibility to the effects of B-cell infection by EBV leads to an increased number of latently infected autoreactive memory B cells, which lodge in organs where their target antigen is expressed, and act there as antigen-presenting cells. When CD4(+) T cells that recognize antigens within the target organ are activated in lymphoid organs by cross-reactivity with infectious agents, they migrate to the target organ but fail to undergo activation-induced apoptosis because they receive a co-stimulatory survival signal from the infected B cells. The autoreactive T cells proliferate and produce cytokines, which recruit other inflammatory cells, with resultant target organ damage and chronic autoimmune disease.

How compelling are the data for Epstein-Barr virus being a trigger for systemic lupus and other autoimmune diseases?

PubMed

Draborg, Anette; Izarzugaza, Jose M G; Houen, Gunnar

2016-07-01

Systemic lupus erythematosus (SLE) is caused by a combination of genetic and acquired immunodeficiencies and environmental factors including infections. An association with Epstein-Barr virus (EBV) has been established by numerous studies over the past decades. Here, we review recent experimental studies on EBV, and present our integrated theory of SLE development. SLE patients have dysfunctional control of EBV infection resulting in frequent reactivations and disease progression. These comprise impaired functions of EBV-specific T-cells with an inverse correlation to disease activity and elevated serum levels of antibodies against lytic cycle EBV antigens. The presence of EBV proteins in renal tissue from SLE patients with nephritis suggests direct involvement of EBV in SLE development. As expected for patients with immunodeficiencies, studies reveal that SLE patients show dysfunctional responses to other viruses as well. An association with EBV infection has also been demonstrated for other autoimmune diseases, including Sjögren's syndrome, rheumatoid arthritis, and multiple sclerosis. Collectively, the interplay between an impaired immune system and the cumulative effects of EBV and other viruses results in frequent reactivation of EBV and enhanced cell death, causing development of SLE and concomitant autoreactivities.

Kaposi's Sarcoma-Associated Herpesvirus Utilizes and Manipulates RNA N6-Adenosine Methylation To Promote Lytic Replication

PubMed Central

Chen, E. Ricky; Nilsen, Timothy W.

2017-01-01

ABSTRACT N6-adenosine methylation (m6A) is the most common posttranscriptional RNA modification in mammalian cells. We found that most transcripts encoded by the Kaposi's sarcoma-associated herpesvirus (KSHV) genome undergo m6A modification. The levels of m6A-modified mRNAs increased substantially upon stimulation for lytic replication. The blockage of m6A inhibited splicing of the pre-mRNA encoding the replication transcription activator (RTA), a key KSHV lytic switch protein, and halted viral lytic replication. We identified several m6A sites in RTA pre-mRNA crucial for splicing through interactions with YTH domain containing 1 (YTHDC1), an m6A nuclear reader protein, in conjunction with serine/arginine-rich splicing factor 3 (SRSF3) and SRSF10. Interestingly, RTA induced m6A and enhanced its own pre-mRNA splicing. Our results not only demonstrate an essential role of m6A in regulating RTA pre-mRNA splicing but also suggest that KSHV has evolved a mechanism to manipulate the host m6A machinery to its advantage in promoting lytic replication. IMPORTANCE KSHV productive lytic replication plays a pivotal role in the initiation and progression of Kaposi's sarcoma tumors. Previous studies suggested that the KSHV switch from latency to lytic replication is primarily controlled at the chromatin level through histone and DNA modifications. The present work reports for the first time that KSHV genome-encoded mRNAs undergo m6A modification, which represents a new mechanism at the posttranscriptional level in the control of viral replication. PMID:28592530

Hepatocellular apoptosis associated with cytotoxic T/natural killer-cell infiltration in chronic active EBV infection.

PubMed

Nomura, Yuko; Kimura, Hiroshi; Karube, Kennosuke; Yoshida, Shiro; Sugita, Yasuo; Niino, Daisuke; Shimizu, Kei; Kimura, Yoshizo; Aoki, Ryosuke; Kiyasu, Junichi; Takeuchi, Masanori; Hashikawa, Keiko; Hirose, Shinichi; Ohshima, Koichi

2009-07-01

The aim of the present study was to identify the mechanism of hepatocellular apoptosis induced by EBV-infected cytotoxic T/natural killer (NK) cells in chronic active EBV infection (CAEBV). Eight patients with CAEBV were studied, and infected T-cell expansion and NK-cell expansion were detected in four patients each. Biopsy or necropsy was performed on lymph node, liver, or spleen, and each specimen was subjected to immunohistochemical double staining of CD3 plus caspase-3 with the addition of cytotoxic markers of T-cell restricted intracellular antigen-1 (TIA-1), perforin, and granzyme B, as well as EBV in situ hybridization (EBV-ISH). In the liver, some of the infiltrating CD3-positive lymphocytes stained positively for EBV-ISH and cytotoxic markers. Double staining of CD3 plus caspase-3 indicated caspase-3 positive hepatocytes with apoptotic features, accompanied by extensive infiltration of CD3-positive cells, which were directly attached to the apoptotic caspase-3 positive hepatocytes. In contrast, far fewer cells stained positive for caspase-3 in lymph node and spleen than in liver. The present findings suggest that in patients with CAEBV, cytotoxic T/NK cells may directly induce hepatocytes to undergo apoptosis more frequently than they do cells in other organs of the reticulo-endothelial system.

Hypothesis: a role for EBV-induced molecular mimicry in Parkinson's disease.

PubMed

Woulfe, John M; Gray, Madison T; Gray, Douglas A; Munoz, David G; Middeldorp, Jaap M

2014-07-01

Current concepts regarding the pathogenesis of Parkinson's disease support a model whereby environmental factors conspire with a permissive genetic background to initiate the disease. The identity of the responsible environmental trigger has remained elusive. There is incontrovertible evidence that aggregation of the neuronal protein alpha-synuclein is central to disease pathogenesis. A novel hypothesis of Parkinson's pathogenesis, articulated by Braak and colleagues, implicates a pathogen acting in the olfactory mucosa and gastrointestinal tract as the inciting agent. In this point-of-view article, we hypothesize that α-synuclein aggregation in Parkinson's disease is an Epstein-Barr virus (EBV)-induced autoimmune phenomenon. Specifically, we have shown evidence for molecular mimicry between the C-terminal region of α-synuclein and a repeat region in the latent membrane protein 1 encoded by EBV. We hypothesize that, in genetically-susceptible individuals, anti-EBV latent membrane protein antibodies targeting the critical repeat region cross react with the homologous epitope on α-synuclein and induce its oligomerization. Consistent with the Braak's proposed pattern of spread, we contend that axon terminals in the lamina propria of the gut are among the initial targets, with subsequent spread of pathology to the CNS. While at this time, we can only provide evidence from the literature and preliminary findings from our own laboratory, we hope that our hypothesis will stimulate the development of tractable experimental systems that can be exploited to test it. Further support for an EBV-induced immune pathogenesis for Parkinson's disease could have profound therapeutic implications. Copyright © 2014 Elsevier Ltd. All rights reserved.

KSHV Targeted Therapy: An Update on Inhibitors of Viral Lytic Replication

PubMed Central

Coen, Natacha; Duraffour, Sophie; Snoeck, Robert; Andrei, Graciela

2014-01-01

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the causative agent of Kaposi’s sarcoma, primary effusion lymphoma and multicentric Castleman’s disease. Since the discovery of KSHV 20 years ago, there is still no standard treatment and the management of virus-associated malignancies remains toxic and incompletely efficacious. As the majority of tumor cells are latently infected with KSHV, currently marketed antivirals that target the virus lytic cycle have shown inconsistent results in clinic. Nevertheless, lytic replication plays a major role in disease progression and virus dissemination. Case reports and retrospective studies have pointed out the benefit of antiviral therapy in the treatment and prevention of KSHV-associated diseases. As a consequence, potent and selective antivirals are needed. This review focuses on the anti-KSHV activity, mode of action and current status of antiviral drugs targeting KSHV lytic cycle. Among these drugs, different subclasses of viral DNA polymerase inhibitors and compounds that do not target the viral DNA polymerase are being discussed. We also cover molecules that target cellular kinases, as well as the potential of new drug targets and animal models for antiviral testing. PMID:25421895

EBV+ lymphoepithelial carcinoma of the parotid gland in Mexican Mestizo patients with chronic autoimmune diseases.

PubMed

Saqui-Salces, Milena; Martinez-Benitez, Braulio; Gamboa-Dominguez, Armando

2006-01-01

Lymphoepithelial carcinomas of the salivary gland are rare tumors constantly associated with Epstein-Barr virus (EBV) and mainly identified in Asiatic and Greenlander population. Four cases have been described in Caucasians, only two with EBV infection. We describe two cases of parotid gland lymphoepithelial carcinomas in Mexican mestizo women in which chronic latent EBV infection was documented by immunohistochemistry and in situ hybridization. One patient had primary Sjögren's syndrome and the other systemic lupus erythematosus of six and three years of evolution, respectively. Epithelial neoplastic cells showed latency pattern II (LMP1+, EBNA-2-, EBER+) with a dense inflammatory infiltrate composed mainly by CD8+ T lymphocytes. Follow-up excluded nasopharyngeal involvement in both patients. This report expands the ethnic groups in which salivary lymphoepithelial carcinomas associated with chronic latent EBV infection have been described, and illustrates for the first time its association with autoimmune diseases in two women living in a region non-endemic for this unusual neoplasm.

The Definition of Epstein Barr Virus (EBV)’s Role in HTLV-III Infected USAF Personnel as Related to Disease Progression.

DTIC Science & Technology

1987-10-27

individuals and patients with acute EBV infectious mononucleosis . Of 124 mouthwash specimens from III patients, 33% were positive for EBV DNA with...controls and persons with acute EBV infectious mononucleosis , including those with oropharyngeal ERV detected by the bioassay. By the quantitative...oropharyngeal secretions compared to patients with acute infectious " mononucleosis (Table 5). EBV genotyping findings. Southern analysis using the Epstein-Barr

Comparative lytic efficacy of rt-PA and ultrasound in porcine versus human clots.

PubMed

Huang, Shenwen; Shekhar, Himanshu; Holland, Christy K

2017-01-01

Porcine thrombi are employed routinely in preclinical models of ischemic stroke. In this study, we examined the differential lytic susceptibility of porcine and human whole blood clots with and without the use of microbubbles and ultrasound (US) as an adjuvant. An in vitro system equipped with time-lapse microscopy was used to evaluate recombinant tissue-plasminogen activator (rt-PA) lysis of porcine and human clots in the same species or cross species plasma. Human and porcine whole blood clots were treated with rt-PA and an echo contrast agent, Definity®, and exposed to intermittent 120 kHz US. The rt-PA lytic efficacy observed for porcine clots in porcine plasma was 22 times lower than for human clots in human plasma reported previously. Further, porcine clots did not exhibit increased lysis with adjuvant Definity® and US exposure. However, the rt-PA lytic susceptibility of the porcine clots in human plasma was similar to that of human clots in human plasma. Human clots perfused with porcine plasma did not respond to rt-PA, but adjuvant use of Definity® and US enhanced lysis. These results reveal considerable differences in lytic susceptibility of porcine clots and human clots to rt-PA. The use of porcine clot models to test new human thrombolytic therapies may necessitate modulation of coagulation and thrombolytic factors to reflect human hemostasis accurately.

Hydroxyapatite crystals as a bone graft substitute in benign lytic lesions of bone

PubMed Central

Gupta, Anil Kumar; Kumar, Praganesh; Keshav, Kumar; Singh, Anant

2015-01-01

Background: Bone grafts are required to fill a cavity created after curettage of benign lytic lesions of the bone. To avoid the problems associated at donor site with autologous bone graft, we require allograft or bone graft substitutes. We evaluated the healing of lytic lesions after hydroxyapatite (HA) grafting by serial radiographs. Materials and Methods: Forty cases of benign lytic lesions of bone were managed by simple curettage and grafting using HA blocks. Commercially available HA of bovine origin (Surgiwear Ltd., Shahjahanpur, India) was used for this purpose. Mean duration of followup was 34.8 months (range 12–84 months). Mean patient age was 19.05 years (range 3–55 years). Radiological staging of graft incorporation was done as per criteria of Irwin et al. 2001. Results: In our series, two cases were in stage I. A total of 11 cases were in stage II and 27 were in stage III. Graft incorporation was radiologically complete by 15 months. Clinical recovery was observed before radiological healing. The average time taken to return to preoperative function was 3 months. Recurrence was observed in giant cell tumor (n = 3) and chondromyxoid fibroma (n = 1). There was no incidence of graft rejection, collapse, growth plate disturbances or antigenic response. Conclusions: We conclude that calcium HA is biologically acceptable bone graft substitute in the management of benign lytic lesions of bone. PMID:26806973

Arsenic mediated disruption of promyelocytic leukemia protein nuclear bodies induces ganciclovir susceptibility in Epstein-Barr positive epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sides, Mark D.; Block, Gregory J.; Shan, Bin

Promyelocytic leukemia protein nuclear bodies (PML NBs) have been implicated in host immune response to viral infection. PML NBs are targeted for degradation during reactivation of herpes viruses, suggesting that disruption of PML NB function supports this aspect of the viral life cycle. The Epstein-Barr virus (EBV) Latent Membrane Protein 1 (LMP1) has been shown to suppress EBV reactivation. Our finding that LMP1 induces PML NB immunofluorescence intensity led to the hypothesis that LMP1 may modulate PML NBs as a means of maintaining EBV latency. Increased PML protein and morphometric changes in PML NBs were observed in EBV infected alveolarmore » epithelial cells and nasopharyngeal carcinoma cells. Treatment with low dose arsenic trioxide disrupted PML NBs, induced expression of EBV lytic proteins, and conferred ganciclovir susceptibility. This study introduces an effective modality to induce susceptibility to ganciclovir in epithelial cells with implications for the treatment of EBV associated pathologies.« less

An overview of the infection of CMV, HSV 1/2 and EBV in Mexican patients with glioblastoma multiforme.

PubMed

Zavala-Vega, Sergio; Castro-Escarpulli, Graciela; Hernández-Santos, Hector; Salinas-Lara, Citlatepetl; Palma, Icela; Mejía-Aranguré, Juan Manuel; Gelista-Herrera, Noemí; Rembao-Bojorquez, Daniel; Ochoa, Sara A; Cruz-Córdova, Ariadnna; Xicohtencatl-Cortes, Juan; Uribe-Gutiérrez, Gabriel; Arellano-Galindo, José

2017-03-01

Several risk factors are involved in glioblastoma, including cytomegalovirus (CMV). This research was carried out to determine the rate of CMV infection, as well as HSV 1/2 and EBV in brain tissue, in patients with glioblastomamultiforme (GBM). The tissues were tested using immunohistochemistry, PCR, in situ hybridization and real-time PCR. At least, one HHV was detected in 21/29 (72%) patients as follows: single infections with HSV-1/2 in 4/21 (19%), EBV in 6/21 (28.6%) and CMV in 1/21 (4.8%). Mixed viral infection, HSV-1/2 and EBV were detected in 4/21 patients (19%), CMV and EBV in 5/21 (23.8%), and HSV-1/2, EBV, and CMV in 1/21. The CMV viral load ranged from 3×10 2 to 4.33×10 5 genome/100ng of tissue. Genotype based on CMV gB was 3/7 where 2/3 was gB1 and 1/3 gB4. HSV, EBV and CMV were frequently found in brain tissues, more in mix in a population reported as highly seropositive. Copyright © 2017 Elsevier GmbH. All rights reserved.

A Cell Culture Model of Latent and Lytic Herpes Simplex Virus Type 1 Infection in Spiral Ganglion.

PubMed

Liu, Yuehong; Li, Shufeng

2015-01-01

Reactivation of latent herpes simplex virus type 1 (HSV-1) in spiral ganglion neurons (SGNs) is supposed to be one of the causes of idiopathic sudden sensorineural hearing loss. This study aims to establish a cell culture model of latent and lytic HSV-1 infection in spiral ganglia. In the presence of acyclovir, primary cultures of SGNs were latently infected with HSV-1 expressing green fluorescent protein. Four days later, these cells were treated with trichostatin A (TSA), a known chemical reactivator of HSV-1. TCID50 was used to measure the titers of virus in cultures on Vero cells. RNA from cultures was detected for the presence of transcripts of ICP27 and latency-associated transcript (LAT) using reverse transcription polymerase chain reaction. There is no detectable infectious HSV-1 in latently infected cultures, whereas they could be observed in both lytically infected and latently infected/TSA-treated cultures. LAT was the only detectable transcript during latent infection, whereas lytic ICP27 transcript was detected in lytically infected and latently infected/TSA-treated cultures. Cultured SGNs can be both latently and lytically infected with HSV-1. Furthermore, latently infected SGNs can be reactivated using TSA, yielding infectious virus.

HDAC6 regulates the dynamics of lytic granules in cytotoxic T lymphocytes

PubMed Central

Núñez-Andrade, Norman; Iborra, Salvador; Trullo, Antonio; Moreno-Gonzalo, Olga; Calvo, Enrique; Catalán, Elena; Menasche, Gaël; Sancho, David; Vázquez, Jesús; Yao, Tso-Pang

2016-01-01

HDAC6 is a tubulin deacetylase involved in many cellular functions related to cytoskeleton dynamics including cell migration and autophagy. In addition, HDAC6 affects antigen-dependent CD4+ T cell activation. In this study, we show that HDAC6 contributes to the cytotoxic function of CD8+ T cells. Immunization studies revealed defective cytotoxic activity in vivo in the absence of HDAC6. Adoptive transfer of wild-type or Hdac6-/- CD8+ T cells to Rag1-/- mice demonstrated specific impairment in CD8+ T cell responses against vaccinia infection. Mechanistically, HDAC6-deficient cytotoxic T lymphocytes (CTLs) showed defective in vitro cytolytic activity related to altered dynamics of lytic granules, inhibited kinesin 1 – dynactin mediated terminal transport of lytic granules to the immune synapse and deficient exocytosis, but not to target cell recognition, T cell receptor (TCR) activation or interferon (IFNγ) production. Our results establish HDAC6 as an effector of the immune cytotoxic response that acts by affecting the dynamics, transport and secretion of lytic granules by CTLs. PMID:26869226

Wide host range and strong lytic activity of Staphylococcus aureus lytic phage Stau2.

PubMed

Hsieh, Sue-Er; Lo, Hsueh-Hsia; Chen, Shui-Tu; Lee, Mong-Chuan; Tseng, Yi-Hsiung

2011-02-01

In searching for an alternative antibacterial agent against multidrug-resistant Staphylococcus aureus, we have isolated and characterized a lytic staphylophage, Stau2. It possesses a double-stranded DNA genome estimated to be about 134.5 kb and a morphology resembling that of members of the family Myoviridae. With an estimated latency period of 25 min and a burst size of 100 PFU/infected cell, propagation of Stau2 in liquid culture gave a lysate of ca. 6 × 10(10) PFU/ml. It was stable at pH 5 to 13 in normal saline at room temperature for at least 4 weeks and at -85°C for more than 2 years, while 1 × 10(9) out of 2 × 10(12) PFU/ml retained infectivity after 36 months at 4°C. Stau2 could lyse 80% of the S. aureus isolates (164/205) obtained from hospitals in Taiwan, with complete lysis of most of the isolates tested within 3 h; however, it was an S. aureus-specific phage because no lytic infection could be found in the coagulase-negative staphylococci tested. Its host range among S. aureus isolates was wider than that of polyvalent phage K (47%), which can also lyse many other staphylococcal species. Experiments with mice demonstrated that Stau2 could provide 100% protection from lethal infection when a multiplicity of infection of 10 was administered immediately after a challenge with S. aureus S23. Considering these results, Stau2 could be considered at least as a candidate for topical phage therapy or an additive in the food industry.

Identification of acidic and aromatic residues in the Zta activation domain essential for Epstein-Barr virus reactivation.

PubMed

Deng, Z; Chen, C J; Zerby, D; Delecluse, H J; Lieberman, P M

2001-11-01

Epstein-Barr virus (EBV) lytic cycle transcription and DNA replication require the transcriptional activation function of the viral immediate-early protein Zta. We describe a series of alanine substitution mutations in the Zta activation domain that reveal two functional motifs based on amino acid composition. Alanine substitution of single or paired hydrophobic aromatic amino acid residues resulted in modest transcription activation defects, while combining four substitutions of aromatic residues (F22/F26/W74/F75) led to more severe transcription defects. Substitution of acidic amino acid residue E27, D35, or E54 caused severe transcription defects on most viral promoters. Promoter- and cell-specific defects were observed for some substitution mutants. Aromatic residues were required for Zta interaction with TFIIA-TFIID and the CREB-binding protein (CBP) and for stimulation of CBP histone acetyltransferase activity in vitro. In contrast, acidic amino acid substitution mutants interacted with TFIIA-TFIID and CBP indistinguishably from the wild type. The nuclear domain 10 (ND10) protein SP100 was dispersed by most Zta mutants, but acidic residue mutations led to reduced, while aromatic substitution mutants led to increased SP100 nuclear staining. Acidic residue substitution mutants had more pronounced defects in transcription activation of endogenous viral genes in latently infected cells and for viral replication, as measured by the production of infectious virus. One mutant, K12/F13, was incapable of stimulating EBV lytic replication but had only modest transcription defects. These results indicate that Zta stimulates viral reactivation through two nonredundant structural motifs, one of which interacts with general transcription factors and coactivators, and the other has an essential but as yet not understood function in lytic transcription.

Role of defective Oct-2 and OCA-B expression in immunoglobulin production and Kaposi's sarcoma-associated herpesvirus lytic reactivation in primary effusion lymphoma.

PubMed

Di Bartolo, Daniel L; Hyjek, Elizabeth; Keller, Shannon; Guasparri, Ilaria; Deng, Hongyu; Sun, Ren; Chadburn, Amy; Knowles, Daniel M; Cesarman, Ethel

2009-05-01

Primary effusion lymphoma (PEL) is a distinct type of B-cell non-Hodgkin lymphoma characterized by the presence of Kaposi's sarcoma-associated herpesvirus (KSHV/human herpesvirus 8). Despite having a genotype and gene expression signature of highly differentiated B cells, PEL does not usually express surface or cytoplasmic immunoglobulin (Ig). We show the lack of Oct-2 and OCA-B transcription factors to be responsible, at least in part, for this defect in Ig production. Like Ig genes, ORF50, the key regulator of the switch from latency to lytic reactivation, contains an octamer motif within its promoter. We therefore examined the impact of Oct-2 and OCA-B on ORF50 activation. The binding of Oct-1 to the ORF50 promoter has been shown to significantly enhance ORF50 transactivation. We found that Oct-2, on the other hand, inhibited ORF50 expression and consequently lytic reactivation by competing with Oct-1 for the octamer motif in the ORF50 promoter. Our data suggest that Oct-2 downregulation in infected cells would be favorable to KSHV in allowing for efficient viral reactivation.

EBV latent membrane protein 1 abundance correlates with patient age but not with metastatic behavior in north African nasopharyngeal carcinomas

PubMed Central

Khabir, Abdelmajid; Karray, Hela; Rodriguez, Sandrine; Rosé, Mathieu; Daoud, Jamel; Frikha, Mounir; Boudawara, Tahia; Middeldorp, Jaap; Jlidi, Rachid; Busson, Pierre

2005-01-01

Background Undifferentiated nasopharyngeal carcinomas are rare in a majority of countries but they occur at a high incidence in South China and to a lesser extent in North Africa. They are constantly associated with the Epstein-Barr virus (EBV) regardless of patient geographic origin. In North Africa, the distribution of NPC cases according to patient age is bi-modal with a large group of patients being around 50 years old (80%) and a smaller group below 25 years old. We and others have previously shown that the juvenile form of NPC has distinct biological characteristics including a low amount of p53 and Bcl2 in the tumor tissue and a low level of anti-EBV IgG and IgA in the peripheral blood. Results To get more insight on potential oncogenic mechanisms specific of these two forms, LMP1 abundance was assessed in 82 NPC patients of both groups, using immuno-histochemistry and semi-quantitative evaluation of tissue staining. Serum levels of anti-EBV antibodies were simultaneously assessed. For LMP1 staining, we used the S12 antibody which has proven to be more sensitive than the common anti-LMP1 CS1-4 for analysis of tissue sections. In all NPC biopsies, at least a small fraction of cells was positively stained by S12. LMP1 abundance was strongly correlated to patient age, with higher amounts of the viral protein detected in specimens of the juvenile form. In contrast, LMP1 abundance was not correlated to the presence of lymph node or visceral metastases, nor to the risk of metastatic recurrence. It was also independent of the level of circulating anti-EBV antibodies. Conclusion The high amount of LMP1 recorded in tumors from young patients confirms that the juvenile form of NPC has specific features regarding not only cellular but also viral gene expression. PMID:15842731

EBV latent membrane protein 1 abundance correlates with patient age but not with metastatic behavior in north African nasopharyngeal carcinomas.

PubMed

Khabir, Abdelmajid; Karray, Hela; Rodriguez, Sandrine; Rosé, Mathieu; Daoud, Jamel; Frikha, Mounir; Boudawara, Tahia; Middeldorp, Jaap; Jlidi, Rachid; Busson, Pierre

2005-04-20

Undifferentiated nasopharyngeal carcinomas are rare in a majority of countries but they occur at a high incidence in South China and to a lesser extent in North Africa. They are constantly associated with the Epstein-Barr virus (EBV) regardless of patient geographic origin. In North Africa, the distribution of NPC cases according to patient age is bi-modal with a large group of patients being around 50 years old (80%) and a smaller group below 25 years old. We and others have previously shown that the juvenile form of NPC has distinct biological characteristics including a low amount of p53 and Bcl2 in the tumor tissue and a low level of anti-EBV IgG and IgA in the peripheral blood. To get more insight on potential oncogenic mechanisms specific of these two forms, LMP1 abundance was assessed in 82 NPC patients of both groups, using immuno-histochemistry and semi-quantitative evaluation of tissue staining. Serum levels of anti-EBV antibodies were simultaneously assessed. For LMP1 staining, we used the S12 antibody which has proven to be more sensitive than the common anti-LMP1 CS1-4 for analysis of tissue sections. In all NPC biopsies, at least a small fraction of cells was positively stained by S12. LMP1 abundance was strongly correlated to patient age, with higher amounts of the viral protein detected in specimens of the juvenile form. In contrast, LMP1 abundance was not correlated to the presence of lymph node or visceral metastases, nor to the risk of metastatic recurrence. It was also independent of the level of circulating anti-EBV antibodies. The high amount of LMP1 recorded in tumors from young patients confirms that the juvenile form of NPC has specific features regarding not only cellular but also viral gene expression.

Mapping regions of Epstein-Barr virus (EBV) glycoprotein B (gB) important for fusion function with gH/gL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Plate, Aileen E.; Reimer, Jessica J.; Jardetzky, Theodore S.

Glycoproteins gB and gH/gL are required for entry of Epstein-Barr virus (EBV) into cells, but the role of each glycoprotein and how they function together to mediate fusion is unclear. Analysis of the functional homology of gB from the closely related primate gammaherpesvirus, rhesus lymphocryptovirus (Rh-LCV), showed that EBV gB could not complement Rh gB due to a species-specific dependence between gB and gL. To map domains of gB required for this interaction, we constructed a panel of EBV/Rh gB chimeric proteins. Analysis showed that insertion of Rh gB from residues 456 to 807 restored fusion function of EBV gBmore » with Rh gH/gL, suggesting this region of gB is important for interaction with gH/gL. Split YFP bimolecular complementation (BiFC) provided evidence of an interaction between EBV gB and gH/gL. Together, our results suggest the importance of a gB-gH/gL interaction in EBV-mediated fusion with B cells requiring the region of EBV gB from 456 to 807.« less

Acute EBV infection masquerading as "In-situ Follicular Lymphoma": a pitfall in the differential diagnosis of this entity.

PubMed

Gru, Alejandro A; Kreisel, Friederike; Duncavage, Eric; Nguyen, TuDung T; Hassan, Anjum; Frater, John L

2013-06-19

We present the case of a 30 year-old man who was referred for evaluation of diffuse lymphadenopathy. Six weeks prior, he noticed darkening of his urine associated with pale stools, nausea and an eventual 30 lb weight loss within a month. The initial laboratory findings showed elevation of the liver enzymes. A CT scan showed mesenteric and periaortic lymphadenopathy with the largest lymph node measuring 2.8 cm. Other laboratory results were otherwise unremarkable (including a normal LDH) with the exception of positive serum antibodies against Epstein-Barr virus (EBV) associated antigens (IgM+ and IgG+). An excisional biopsy of 4 of the small neck lymph nodes showed a normal architecture with prominent follicles and an intact capsule. But, by immunohistochemistry two of the follicles showed aberrant coexpression of BCL-2, in addition to CD10 and BCL-6. In-situ hybridization for early Epstein-Barr virus mRNA (EBER) and immunohistochemistry for latent membrane protein-1 (LMP-1) stained both scattered positive cells, as well as BCL-2 positive B-cells. Although an original diagnosis of in-situ follicular lymphoma was favored at an outside facility, additional interphase fluorescence in situ hybridization (FISH) studies for t(14;18);(IGH-BCL2) rearrangement (performed on the BCL-2 + follicles microdissected from the tissue block; Abott probe dual colour fusion) and molecular studies (IGH gene rearrangement by PCR, also performed on the microdissected follicles) were negative. Serologic studies (positive EBV antibodies) and immunostains in conjunction with the molecular studies confirmed the reactive nature of the changes. Our case also shows direct immunopathogenic evidence of BCL-2 expression among the EBV-infected cells, which has to our knowledge not been previously documented in vivo. A diagnosis of EBV infection should, therefore, be considered when confronted with BCL-2 expression in germinal centers, particularly in younger individuals, as the diagnosis of FLIS may

Regulation of tumour related genes by dynamic epigenetic alteration at enhancer regions in gastric epithelial cells infected by Epstein-Barr virus.

PubMed

Okabe, Atsushi; Funata, Sayaka; Matsusaka, Keisuke; Namba, Hiroe; Fukuyo, Masaki; Rahmutulla, Bahityar; Oshima, Motohiko; Iwama, Atsushi; Fukayama, Masashi; Kaneda, Atsushi

2017-08-11

Epstein-Barr virus (EBV) infection is associated with tumours such as Burkitt lymphoma, nasopharyngeal carcinoma, and gastric cancer. We previously showed that EBV(+) gastric cancer presents an extremely high-methylation epigenotype and this aberrant DNA methylation causes silencing of multiple tumour suppressor genes. However, the mechanisms that drive EBV infection-mediated tumorigenesis, including other epigenomic alteration, remain unclear. We analysed epigenetic alterations induced by EBV infection especially at enhancer regions, to elucidate their contribution to tumorigenesis. We performed ChIP sequencing on H3K4me3, H3K4me1, H3K27ac, H3K27me3, and H3K9me3 in gastric epithelial cells infected or not with EBV. We showed that repressive marks were redistributed after EBV infection, resulting in aberrant enhancer activation and repression. Enhancer dysfunction led to the activation of pathways related to cancer hallmarks (e.g., resisting cell death, disrupting cellular energetics, inducing invasion, evading growth suppressors, sustaining proliferative signalling, angiogenesis, and tumour-promoting inflammation) and inactivation of tumour suppressive pathways. Deregulation of cancer-related genes in EBV-infected gastric epithelial cells was also observed in clinical EBV(+) gastric cancer specimens. Our analysis showed that epigenetic alteration associated with EBV-infection may contribute to tumorigenesis through enhancer activation and repression.

Association of transforming growth factor-beta1 gene polymorphism in the development of Epstein-Barr virus-related hematologic diseases.

PubMed

Hatta, Kanako; Morimoto, Akira; Ishii, Eiichi; Kimura, Hiroshi; Ueda, Ikuyo; Hibi, Shigeyoshi; Todo, Shinjiro; Sugimoto, Tohru; Imashuku, Shinsaku

2007-11-01

Epstein-Barr virus (EBV) is etiologically associated with various hematologic disorders, including primary acute infectious mononucleosis (IM), hemophagocytic lymphohistiocytosis (EBV-HLH), chronic active EBV infection (CAEBV) and malignant lymphomas. Although cytokines play a central role in EBV-related immune responses, the exact mechanisms causing different clinical responses remain unclear. In this study, the pattern of cytokine gene polymorphisms was comparatively analyzed in EBV-related diseases. Eighty-nine patients with EBV-related disease were analyzed; 30 with IM, 28 with EBV-HLH and 31 with CAEBV. Eighty-one EBV-seropositive healthy adults were also used as controls. Associations with polymorphisms of various cytokines, including interleukin (IL)-1 alpha and IL-1 beta were evaluated. The gene polymorphisms were typed by polymerase chain reaction with sequence-specific primers. A significant difference of polymorphisms was found for transforming growth factor (TGF)-beta1; the frequency of TGF-beta1 codon 10 C allele was significantly higher in patients with EBV-related diseases than in controls (p<0.001). The difference was significant in patients with IM or HLH (p<0.001), but not in those with CAEBV (p=0.127), compared with controls. As regards other cytokines, the frequency of the IL-1 alpha -889 C allele was significantly lower in patients with IM than in controls (p<0.05). Our results suggests that TGF-beta1 codon 10 C allele plays a role in the development of EBV-related diseases and that the IL-1 alpha -889 C allele may be involved in response failure and sequential progression into the development of HLH.

Ataxia and Encephalitis in a Young Adult with EBV Mononucleosis: A Case Report.

PubMed

Hussain, Rashid S; Hussain, Naaz A

2013-01-01

Neurological manifestations of mononucleosis are extremely rare, occurring in about 1% of all cases. However, when they occur, appropriate treatment must be undertaken to ensure appropriate symptomatic management and reduce morbidity. We present the case of a 25-year-old graduate student with weeklong complaints of fever, sore throat, fatigue, nausea, and "dizziness." She later developed increased sleep requirements, ataxia, vertigo, and nystagmus with a positive EBV IgM titer confirming acute infectious mononucleosis. The patient was clinically diagnosed with EBV-associated cerebellitis and encephalitis, displaying neurological and psychiatric impairment commonly seen in postconcussion syndrome. MRI showed no acute changes. She was started on valacyclovir and a prednisone taper, recovering by the end of twelve weeks. Though corticosteroids and acyclovir are not recommended therapy in patients presenting with EBV-associated ataxia, clinicians may want to keep a low threshold to start these medications in case more serious neurological sequelae develop.

The Definition of Epstein Barr Virus (EBV)’s Role in HTLV-III Infected USAF Personnel as Related to Disease Progression

DTIC Science & Technology

1989-04-15

pathologic tissues: prevalence and titer of infectious EBV according to a transformation assay (8, 9), prevalence and quantity of EBV - DNA by spot...containing EBV - DNA were also reported in increased frequency in homosexuals and AIDS patients (3). This latter finding is being noted moreso, possibly as a...digestions (11). In addition, the concomitant presence of inLitr. HIV-l antigen and infectious virus was searched for in established EBV cell cultures

Viral colonization in exhaled breath condensate of lung cancer patients: Possible role of EBV and CMV.

PubMed

Carpagnano, Giovanna E; Lacedonia, Donato; Natalicchio, Maria Iole; Cotugno, Grazia; Zoppo, Luigi; Martinelli, Domenico; Antonetti, Raffaele; Foschino-Barbaro, Maria Pia

2018-02-01

Today, an increasing interest is being addressed to the viral etiology of lung tumors. As a consequence, research efforts are currently being directed to the identification of the new viruses involved in lung carcinogenesis toward which the screening programs could be directed. The aim of this study was to investigate the airways colonization by the Epstein-Barr virus (EBV) and Citomegalovirus (CMV) in patients affected by lung cancer using, as a respiratory non-invasive sample, the exhaled breath condensate (EBC). About 70 lung-cancer patients and 40 controls were enrolled. All subjects underwent bronchial brushing and EBC collection. EBV-DNA and CMV-DNA were evaluated in both samples by real-time PCR assay. They were able to detect EBV and CMV in the EBC. An increase of the EBV positivity in non-small cell lung cancer (NSCLC) patients compared with controls and of the CMV in advanced stages of lung cancer were observed. The association of the positivity of the cytology and the CMV test (in EBC or brushing) slightly increased the sensitivity of malignant diagnosis. EBV and CMV resulted detectable in the EBC. In consideration of the potential involvement of these viruses in lung cancer, which was confirmed in this study, future studies in this direction were supported. © 2016 John Wiley & Sons Ltd.

Comparative lytic efficacy of rt-PA and ultrasound in porcine versus human clots

PubMed Central

Shekhar, Himanshu; Holland, Christy K.

2017-01-01

Introduction Porcine thrombi are employed routinely in preclinical models of ischemic stroke. In this study, we examined the differential lytic susceptibility of porcine and human whole blood clots with and without the use of microbubbles and ultrasound (US) as an adjuvant. Materials and methods An in vitro system equipped with time-lapse microscopy was used to evaluate recombinant tissue-plasminogen activator (rt-PA) lysis of porcine and human clots in the same species or cross species plasma. Human and porcine whole blood clots were treated with rt-PA and an echo contrast agent, Definity®, and exposed to intermittent 120 kHz US. Results and conclusions The rt-PA lytic efficacy observed for porcine clots in porcine plasma was 22 times lower than for human clots in human plasma reported previously. Further, porcine clots did not exhibit increased lysis with adjuvant Definity® and US exposure. However, the rt-PA lytic susceptibility of the porcine clots in human plasma was similar to that of human clots in human plasma. Human clots perfused with porcine plasma did not respond to rt-PA, but adjuvant use of Definity® and US enhanced lysis. These results reveal considerable differences in lytic susceptibility of porcine clots and human clots to rt-PA. The use of porcine clot models to test new human thrombolytic therapies may necessitate modulation of coagulation and thrombolytic factors to reflect human hemostasis accurately. PMID:28545055

The Definition of Epstein Barr Virus (EBV)’s Role in HTLV-III Infected USAF Personnel as Related to Disease Progression

DTIC Science & Technology

1988-12-27

were considerably greater than those noted in patients with acute EBV induced infectious mononucleosis (IM), while the antibody levels to early... infectious (WR 1 - 6) (WR 1 only) (WR 1) Controls mononucleosis Oropharyngeat EBV 14/20 (70 ) 6/10 (60 ) 19/30 (63 ) 5/23 (21.7) 17/19 (89.5) Spontaneous... EBV infection in patients with ARC and AIDS. B cell lymphomas containing EBV - DNA are being reported in increased frequency in homosexuals and AIDS

Clinicopathological states of Epstein-Barr virus-associated T/NK-cell lymphoproliferative disorders (severe chronic active EBV infection) of children and young adults.

PubMed

Suzuki, Keiko; Ohshima, Koichi; Karube, Kennosuke; Suzumiya, Junji; Ohga, Shouichi; Ishihara, Shigehiko; Tamura, Kazuo; Kikuchi, Masahiro

2004-05-01

Epstein-Barr virus (EBV)-associated T/NK-cell lymphoproliferative disorders (LPD) of children and young adults are sometimes termed as severe chronic active EBV infection (CAEBV), and are associated with an aggressive clinical course. However, these clinicopathological states and the role of EBV have not been clarified. A retrospective study was performed on 43 children and adult patients, who manifested EBV-associated T/NK-cell lymphoproliferative disorders (EBV-T/NK-LPD) and most of whom had experienced general illness with CAEBV for several months or years. Clinicopathologically, 43 patients were classified into four groups: group A (smoldering state) (n=7), morphological non-neoplastic LPD with chronic clinical course (several years); group B (chronic state) (n=10), non-neoplastic LPD with clonal EBV-infected cells and a chronic course; group C (leukemia/lymphoma state) (n=22), neoplastic LPD with a subacute course (years to months); group D (fulminant state) (n=4), neoplastic LPD with a fulminant course (weeks to days). The 43 patients comprised 21 males and 22 females. The median age of group A was 14 years, group B 12 years, group C 17 years, and group D 1 year. Four of 7 patients in group A, 3 of 10 in group B, 12 of 22 in group C, and all 4 in group D have died. Causes of death included hemophagocytic syndrome and/or tumor death. Genotypically and phenotypically, group C was composed of peripheral T-cell lymphoma (PTCL), and NK-cell leukemia/lymphoma (NKLL), and group D comprised cases of PTCL. Groups A and B exhibited increased NK- or T-cells (CD8>CD4), and rare B-cells. Serologic titers of EBV were only modestly elevated or not elevated in almost all cases. EBV early RNA-1 (EBER-1)-expressing EBV-infected cells were frequently encountered in each group, but the number of infected cells varied between the cases. The EBV genotype did not differ between the groups. Our findings support an important pathogenic role for EBV-infected T/NK-cell infection

LMP1 and Dynamic Progressive Telomere Dysfunction: A Major Culprit in EBV-Associated Hodgkin's Lymphoma.

PubMed

Knecht, Hans; Mai, Sabine

2017-06-27

Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) is expressed in germinal-center-derived, mononuclear Hodgkin (H) and multinuclear, diagnostic Reed-Sternberg (RS) cells in classical EBV-positive Hodgkin's lymphoma (cHL). LMP1 expression in EBV-negative H-cell lines results in a significantly increased number of RS cells. In a conditional, germinal-center-derived B-cell in vitro system, LMP1 reversibly down-regulates the shelterin proteins, telomeric repeat binding factor (TRF)1, TRF2, and protection of telomeres (POT)1. This down-regulation is associated with progressive 3D shelterin disruption, resulting in telomere dysfunction, progression of complex chromosomal rearrangements, and multinuclearity. TRF2 appears to be the key player. Thus, we hypothesize that the 3D interaction of telomeres and TRF2 is disrupted in H cells, and directly associated with the formation of H and RS cells. Using quantitative 3D co-immuno-TRF2-telomere fluorescent in situ hybridization (3D TRF2/Telo-Q-FISH) applied to monolayers of primary H and RS cells, we demonstrate TRF2-telomere dysfunction in EBV-positive cHL. However, in EBV-negative cHL a second molecular mechanism characterized by massive up-regulation of TRF2, but attrition of telomere signals, is also identified. These facts point towards a shelterin-related pathogenesis of cHL, where two molecularly disparate mechanisms converge at the level of 3D Telomere-TRF2 interactions, leading to the formation of RS cells.

Identification and characterization of an autolysin gene, atlg, from Streptococcus sobrinus.

PubMed

Yamada, Arisa; Tamura, Haruki; Kato, Hirohisa

2009-02-01

AtlA is a major cell-lytic enzyme called autolysin in Streptococcus mutans. In this study, we identified the atlg gene-encoding autolysin (Atlg), consisting of 863 residues from Streptococcus sobrinus 6715DP, and confirmed lytic activity of recombinant Atlg by zymography of S. sobrinus cells. An atlA-inactivated mutant was constructed in S. mutans Xc, and the atlg gene product was characterized by plasmid complementation. Microscopic analysis, saliva-induced aggregation assay and autolysis assay of static cultures in air revealed that the atlg gene product partially complemented the role of AtlA. Furthermore, the capability of biofilm formation of the atlA-deficient mutant cultivated in air was restored by plasmid comprising the atlg gene. These findings suggest that Atlg may be involved in cell separation and biofilm formation in S. sobrinus.

Active CMV and EBV infections in renal transplant recipients with unexplained fever and elevated serum creatinine.

PubMed

Hasannia, Tahereh; Moosavi Movahed, Seyed Majid; Vakili, Rosita; Rafatpanah, Houshang; Hekmat, Reza; Valizadeh, Narges; Rezaee, Seyed Abdolrahim

2016-10-01

Proper identification of active cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections are helpful for monitoring antiviral treatment in transplant recipients. Qualitative and quantitative CMV, EBV DNA PCR techniques in the context of serological tests are performed for early detection and differentiation of active and latent CMV and EBV infections in renal transplantation. Basically, 129 renal transplanted recipients monitored carefully and hospitalized for unexplained elevated creatinine levels or high fever and 21 of their donors were studied. CMV DNA was detected in 63.5% of the febrile episodes following transplantation and in 46.42% of readmitted patients using qualitative PCR method. In the first group, 15% of the patients and in the second group 42.85% of the patients had copy numbers more than cutoff point (900 copies/mL). Cutoff point had 100% sensitivity and 82.5% specificity for active and symptomatic CMV infection. Only 15.5% of the subjects were positive for EBV infection by qualitative PCR method. Among them 5% had >2000 copies/mL and were symptomatic. One subject with a history of three times hospitalization had higher EBV viral load and developed post-transplant lymphoproliferative disorder. CMV load was significantly correlated with elevated creatinine levels (OR = 3.1, p = 0.006), abnormal heart sounds (OR = 4.7; p = 0.02) and hypertension (OR = 3.6; p = 0.03). Only qRT-PCR could differentiate between latent and active infections and might be clinically useful for monitoring symptomatic CMV and EBV infections and initiation of the antiviral therapy. Elevated creatinine levels, hypertension, and abnormal heart sounds could be considered as main manifestations of HCMV infection in kidney recipients.

Wide Host Range and Strong Lytic Activity of Staphylococcus aureus Lytic Phage Stau2▿

PubMed Central

Hsieh, Sue-Er; Lo, Hsueh-Hsia; Chen, Shui-Tu; Lee, Mong-Chuan; Tseng, Yi-Hsiung

2011-01-01

In searching for an alternative antibacterial agent against multidrug-resistant Staphylococcus aureus, we have isolated and characterized a lytic staphylophage, Stau2. It possesses a double-stranded DNA genome estimated to be about 134.5 kb and a morphology resembling that of members of the family Myoviridae. With an estimated latency period of 25 min and a burst size of 100 PFU/infected cell, propagation of Stau2 in liquid culture gave a lysate of ca. 6 × 1010 PFU/ml. It was stable at pH 5 to 13 in normal saline at room temperature for at least 4 weeks and at −85°C for more than 2 years, while 1 × 109 out of 2 × 1012 PFU/ml retained infectivity after 36 months at 4°C. Stau2 could lyse 80% of the S. aureus isolates (164/205) obtained from hospitals in Taiwan, with complete lysis of most of the isolates tested within 3 h; however, it was an S. aureus-specific phage because no lytic infection could be found in the coagulase-negative staphylococci tested. Its host range among S. aureus isolates was wider than that of polyvalent phage K (47%), which can also lyse many other staphylococcal species. Experiments with mice demonstrated that Stau2 could provide 100% protection from lethal infection when a multiplicity of infection of 10 was administered immediately after a challenge with S. aureus S23. Considering these results, Stau2 could be considered at least as a candidate for topical phage therapy or an additive in the food industry. PMID:21148689

Detection and quantification of Epstein-Barr virus EBER1 in EBV-infected cells by fluorescent in situ hybridization and flow cytometry

NASA Technical Reports Server (NTRS)

Stowe, R. P.; Cubbage, M. L.; Sams, C. F.; Pierson, D. L.; Barrett, A. D.

1998-01-01

A rapid and highly sensitive fluorescent in situ hybridization (FISH) assay was developed to detect Epstein Barr virus (EBV)-infected cells in peripheral blood. Multiple fluorescein-labeled antisense oligonucleotide probes were designed to hybridize to the EBER1 transcript, which is highly expressed in latently infected cells. After a rapid (30 min) hybridization, the cells were analyzed by flow cytometry. EBER1 was detected in several positive control cell lines that have variable numbers of EBV genome copies. No EBER1 was detected in two known EBV-negative cell lines. Northern blot analyses confirmed the presence and quantity of EBER1 transcripts in each cell line. This method was used to quantify the number of EBV-infected cells in peripheral blood from a patient with chronic mononucleosis. These results indicate that EBV-infected cells can be detected at the single cell level, and that this assay can be used to quantify the number of EBV-infected cells in clinical samples.

Testing protozoacidal activity of ligand-lytic peptides against termite gut protozoa in vitro (protozoa culture) and in vivo (microinjection into termite hindgut).

PubMed

Husseneder, Claudia; Sethi, Amit; Foil, Lane; Delatte, Jennifer

2010-12-29

We are developing a novel approach to subterranean termite control that would lead to reduced reliance on the use of chemical pesticides. Subterranean termites are dependent on protozoa in the hindguts of workers to efficiently digest wood. Lytic peptides have been shown to kill a variety of protozoan parasites (Mutwiri et al. 2000) and also protozoa in the gut of the Formosan subterranean termite, Coptotermes formosanus (Husseneder and Collier 2009). Lytic peptides are part of the nonspecific immune system of eukaryotes, and destroy the membranes of microorganisms (Leuschner and Hansel 2004). Most lytic peptides are not likely to harm higher eukaryotes, because they do not affect the electrically neutral cholesterol-containing cell membranes of higher eukaryotes (Javadpour et al. 1996). Lytic peptide action can be targeted to specific cell types by the addition of a ligand. For example, Hansel et al. (2007) reported that lytic peptides conjugated with cancer cell membrane receptor ligands could be used to destroy breast cancer cells, while lytic peptides alone or conjugated with non-specific peptides were not effective. Lytic peptides also have been conjugated to human hormones that bind to receptors on tumor cells for targeted destruction of prostate and testicular cancer cells (Leuschner and Hansel 2004). In this article we present techniques used to demonstrate the protozoacidal activity of a lytic peptide (Hecate) coupled to a heptapeptide ligand that binds to the surface membrane of protozoa from the gut of the Formosan subterranean termite. These techniques include extirpation of the gut from termite workers, anaerobic culture of gut protozoa (Pseudotrichonympha grassii, Holomastigotoides hartmanni,Spirotrichonympha leidyi), microscopic confirmation that the ligand marked with a fluorescent dye binds to the termite gut protozoa and other free-living protozoa but not to bacteria or gut tissue. We also demonstrate that the same ligand coupled to a lytic

Therapeutic Strategies against Epstein-Barr Virus-Associated Cancers Using Proteasome Inhibitors

PubMed Central

Hui, Kwai Fung; Tam, Kam Pui

2017-01-01

Epstein-Barr virus (EBV) is closely associated with several lymphomas (endemic Burkitt lymphoma, Hodgkin lymphoma and nasal NK/T-cell lymphoma) and epithelial cancers (nasopharyngeal carcinoma and gastric carcinoma). To maintain its persistence in the host cells, the virus manipulates the ubiquitin-proteasome system to regulate viral lytic reactivation, modify cell cycle checkpoints, prevent apoptosis and evade immune surveillance. In this review, we aim to provide an overview of the mechanisms by which the virus manipulates the ubiquitin-proteasome system in EBV-associated lymphoid and epithelial malignancies, to evaluate the efficacy of proteasome inhibitors on the treatment of these cancers and discuss potential novel viral-targeted treatment strategies against the EBV-associated cancers. PMID:29160853

Therapeutic Strategies against Epstein-Barr Virus-Associated Cancers Using Proteasome Inhibitors.

PubMed

Hui, Kwai Fung; Tam, Kam Pui; Chiang, Alan Kwok Shing

2017-11-21

Epstein-Barr virus (EBV) is closely associated with several lymphomas (endemic Burkitt lymphoma, Hodgkin lymphoma and nasal NK/T-cell lymphoma) and epithelial cancers (nasopharyngeal carcinoma and gastric carcinoma). To maintain its persistence in the host cells, the virus manipulates the ubiquitin-proteasome system to regulate viral lytic reactivation, modify cell cycle checkpoints, prevent apoptosis and evade immune surveillance. In this review, we aim to provide an overview of the mechanisms by which the virus manipulates the ubiquitin-proteasome system in EBV-associated lymphoid and epithelial malignancies, to evaluate the efficacy of proteasome inhibitors on the treatment of these cancers and discuss potential novel viral-targeted treatment strategies against the EBV-associated cancers.

CD4(+) T-cell responses to Epstein-Barr virus (EBV) latent membrane protein 1 in infectious mononucleosis and EBV-associated non-Hodgkin lymphoma: Th1 in active disease but Tr1 in remission.

PubMed

Marshall, Neil A; Culligan, Dominic J; Johnston, Peter W; Millar, Colin; Barker, Robert N; Vickers, Mark A

2007-10-01

Primary infection with Epstein-Barr virus (EBV) in childhood is usually asymptomatic, whereas infection in adolescence may result in infectious mononucleosis (IM) often followed by a fatigue syndrome. EBV latent membrane protein 1 (LMP1) is expressed in latency and in many EBV-associated tumours, including non-Hodgkin lymphoma (NHL). Given the regulatory nature of the CD4(+) T-cell response against LMP1 previously reported in healthy donors, we investigated whether patients with active EBV-driven disease can nevertheless mount effector [T-helper cell, type 1 (Th1)] anti-LMP1 responses. We therefore performed a longitudinal study of the nature of CD4(+) T-cell responses to LMP1 in four patients with IM, and five patients with NHL. In both groups, responses changed with time. During symptomatic infection or active tumour growth, responses were dominated by a Th1 effector phenotype, but switched to a regulatory interleukin-10 response upon recovery. In addition, the fine specificities of the T cells driving these responses evolved. This study showed the dynamic nature of CD4(+) T-cell responses to LMP1, and demonstrated that, although patients can mount Th1 effector responses, recovery from IM and NHL is associated with regulatory responses.

Adult T-cell leukemia/lymphoma with EBV-positive Hodgkin-like cells

PubMed Central

Venkataraman, Girish; Berkowitz, Jonathan; Morris, John C.; Janik, John E.; Raffeld, Mark A.; Pittaluga, Stefania

2011-01-01

SUMMARY Hodgkin-like cells (HLC) have been described in a variety of non-Hodgkin lymphomas (NHL) including chronic lymphocytic leukemia (CLL) and peripheral T-cell lymphoma (PTCL). There have been rare reports in the Japanese population of human T-cell lymphotrophic virus-1 (HTLV-1)-associated adult T-cell leukemia/lymphoma (ATLL) harboring HLC; however, no similar cases have been described in western patients. We report a 53-year-old African-American man that presented with progressive weakness and lethargy, and was found to have generalized lymphadenopathy and hypercalcemia. A lymph node biopsy showed involvement by ATLL with scattered Epstein-Barr virus (EBV)-positive cells, some of which resembled Hodgkin cells that had a B-cell phenotype, consistent with an Epstein-Barr virus-lymphoproliferative disorder (LPD). The patient had stage 4 disease with bone marrow involvement. In light of the associated B-cell lymphoproliferative process, the patient was treated with six cycles of intensive chemotherapy that targeted both the ATLL and the EBV-LPD that resulted in a complete response. An awareness of the association of EBV-LPD with Hodgkin-like cells in the context of ATLL is necessary to avoid potential misdiagnosis and to aid in therapeutic decisions. PMID:21315416

Calcium Signaling throughout the Toxoplasma gondii Lytic Cycle

PubMed Central

Borges-Pereira, Lucas; Budu, Alexandre; McKnight, Ciara A.; Moore, Christina A.; Vella, Stephen A.; Hortua Triana, Miryam A.; Liu, Jing; Garcia, Celia R. S.; Pace, Douglas A.; Moreno, Silvia N. J.

2015-01-01

Toxoplasma gondii is an obligate intracellular parasite that invades host cells, creating a parasitophorous vacuole where it communicates with the host cell cytosol through the parasitophorous vacuole membrane. The lytic cycle of the parasite starts with its exit from the host cell followed by gliding motility, conoid extrusion, attachment, and invasion of another host cell. Here, we report that Ca2+ oscillations occur in the cytosol of the parasite during egress, gliding, and invasion, which are critical steps of the lytic cycle. Extracellular Ca2+ enhances each one of these processes. We used tachyzoite clonal lines expressing genetically encoded calcium indicators combined with host cells expressing transiently expressed calcium indicators of different colors, and we measured Ca2+ changes in both parasites and host simultaneously during egress. We demonstrated a link between cytosolic Ca2+ oscillations in the host and in the parasite. Our approach also allowed us to measure two new features of motile parasites, which were enhanced by Ca2+ influx. This is the first study showing, in real time, Ca2+ signals preceding egress and their direct link with motility, an essential virulence trait. PMID:26374900

[The study of gene mutations in unknown refractory viral infection and primary hemophagocytic lymphohistiocytosis].

PubMed

Tong, Chun-Rong; Liu, Hong-Xing; Xie, Jian-Jun; Wang, Fang; Cai, Peng; Wang, Hui; Zhu, Juan; Teng, Wen; Zhang, Xian; Yang, Jun-Fang; Zhang, Ya-Li; Fei, Xin-Hong; Zhao, Jie; Yin, Yu-Ming; Wu, Tong; Wang, Jing-Bo; Sun, Yuan; Liu, Rong; Shi, Xiao-Dong; Lu, Dao-Pei

2011-04-01

To study the type and corresponding clinical characteristics of primary hemophagocytic lymphohistiocytosis (HLH) associated immune gene mutations in the refractory virus infection or HLH of unknown causes. From December 2009 to July 2010, the patients with refractory virus infection or HLH of unknown causes were screened for the primary HLH associated immune genes mutations by DNA sequence analysis, including PRF1, UNC13D, STX11, STXBP2, SH2D1A and XIAP. The clinical characteristics and outcomes were followed up. Totally 25 patients with refractory virus infection or HLH of unknown causes were investigated for the 6 genes and 13 cases were found carrying gene mutations, composing of 6 of PRF1 mutation, 3 of UNC13D, and each one of STX11, XIAP, SH2D1A and STXBP2, respectively. Among the 13 cases with gene mutations, 5 suffered from Epstein-Barr virus associated HLH (EBV-HLH), 1 human herpes virus 7 associated HLH (HHV7-HLH), 1 HLH without causes, 4 chronic activated EB virus infection (CAEBV) with 1 progressing to Hodgkin's lymphoma carrying abnormal chromosome of t(15;17) (q22;q25) and hyperdiploid, 2 EBV associated lymphoma. Among the other 12 patients without gene mutation, 4 suffered from EBV-HLH with 1 progressing to peripheral T lymphoma, 8 suffered from CAEBV. Primary HLH associated immune gene mutations are critical causes of refractory virus infection of unknown causes, most patients manifest as HLH, some cases appear in CAEBV and EBV associated lymphoma. DNA sequence analysis is helpful to early diagnosis and correct decision-making for treatment.

Using Phage Lytic Enzymes to Destroy Pathogenic and BW Bacteria

DTIC Science & Technology

2005-07-14

against antibiotic resistant Enterococcus faecalis and Enterococcus faecium . J Bacteriol. 186:4808-12. Cheng, Q., D. Nelson, S. Zhu, and V.A...Lysins from Enterococcus faecalis RU-654 3. Fischetti, Vincent A. Schuch, Raymond Lytic Enzymes and spore surface antigens for detection and

Peripheral blood lymphocytes express recombination-activating genes 1 and 2 during Epstein-Barr virus-induced infectious mononucleosis.

PubMed

Wagner, Hans-Joachim; Scott, Rona S; Buchwald, Dedra; Sixbey, John W

2004-09-01

Implicit in the persistence of Epstein-Barr virus (EBV) in B lymphocytes is the successful circumvention of ongoing cell selection for competence of B cell receptors (BCRs). Because the EBV infection of B cells in vitro induces enzymatic machinery that is responsible for secondary immunoglobulin gene rearrangement, we examined the expression of the recombination-activating genes (RAGs) in peripheral blood mononuclear cells (PBMCs) from 26 patients with infectious mononucleosis (IM). RAG1 and/or RAG2 RNA was detected in PBMCs from 42% of patients with IM but not from healthy control subjects. EBV may usurp the cellular mechanism that diversifies the BCR, to guarantee a level of survival signaling sufficient for its own persistence.

An epidemiologic study of index and family infectious mononucleosis and adult Hodgkin's disease (HD): evidence for a specific association with EBV+ve HD in young adults.

PubMed

Alexander, Freda E; Lawrence, Davia J; Freeland, June; Krajewski, Andrew S; Angus, Brian; Taylor, G Malcolm; Jarrett, Ruth F

2003-11-01

Infectious mononucleosis (IM) is an established risk factor for Hodgkin's disease (HD). A substantial minority (33%) of cases of HD have Epstein-Barr virus (EBV) DNA within the malignant cells (are EBV+ve). It is unclear whether risk after IM applies specifically to EBV+ve HD. We report the results of a population-based case-control study of HD in adults (n = 408 cases of classical HD, 513 controls) aged 16-74 years; the case series included 113 EBV+ve and 243 EBV+ve HD. Analyses compared total HD, EBV+ve HD and EBV-ve HD with the controls and EBV+ve HD with EBV-ve HD cases using, mainly, logistic regression. Regression analyses were adjusted for gender, age-group and socioeconomic status, and were performed for the whole age range and separately for young (< 35 years) and old adults (> or = 35 years); formal tests of effect modification by age were included. For the young adults, reported IM in index or relative was strongly and significantly associated with EBV+ve HD when compared to controls (odds ratio [OR] = 2.94, 95% confidence interval [CI]: 1.08-7.98 and OR = 5.22, 95% CI: 2.15-12.68, respectively). These results may be interpreted as indications that late first exposure to EBV increases risk of HD, especially in young adults; this applies primarily to EBV+ve HD. Copyright 2003 Wiley-Liss, Inc.

A possible link between the Epstein-Barr virus infection and autoimmune thyroid disorders.

PubMed

Dittfeld, Anna; Gwizdek, Katarzyna; Michalski, Marek; Wojnicz, Romuald

2016-01-01

The Epstein-Barr virus (EBV), also known as human herpesvirus 4, is a member of the Herpesviridae virus family. EBV infection can cause infectious mononucleosis (IM) in the lytic phase of EBV's life cycle. Past EBV infection is associated with lymphomas, and may also result in certain allergic and autoimmune diseases. Although potential mechanisms of autoimmune diseases have not been clearly elucidated, both genetic and environmental factors, such as infectious agents, are considered to be responsible for their development. In addition, EBV modifies the host immune response. The worldwide prevalence of autoimmune diseases shows how common this pathogen is. Normally, the virus stays in the body and remains dormant throughout life. However, this is not always the case, and a serious EBV-related illness may develop later in life. This explains the chronic course of autoimmune diseases that is often accompanied by exacerbations of symptoms. Based on the present studies, EBV infection can cause autoimmune diseases, such as systemic lupus erythematosus (SLE), multiple sclerosis (MS), rheumatoid arthritis (RA), Sjögren's syndrome, and autoimmune hepatitis. The EBV has also been reported in patients with autoimmune thyroid disorders. Although EBV is not the only agent responsible for the development of autoimmune thyroid diseases, it can be considered a contributory factor.

Augmentation of failed human vertebrae with critical un-contained lytic defect restores their structural competence under functional loading: An experimental study.

PubMed

Alkalay, Ron N; von Stechow, Dietrich; Hackney, David B

2015-07-01

Lytic spinal lesions reduce vertebral strength and may result in their fracture. Vertebral augmentation is employed clinically to provide mechanical stability and pain relief for vertebrae with lytic lesions. However, little is known about its efficacy in strengthening fractured vertebrae containing lytic metastasis. Eighteen unembalmed human lumbar vertebrae, having simulated uncontained lytic defects and tested to failure in a prior study, were augmented using a transpedicular approach and re-tested to failure using a wedge fracture model. Axial and moment based strength and stiffness parameters were used to quantify the effect of augmentation on the structural response of the failed vertebrae. Effects of cement volume, bone mineral density and vertebral geometry on the change in structural response were investigated. Augmentation increased the failed lytic vertebral strength [compression: 85% (P<0.001), flexion: 80% (P<0.001), anterior-posterior shear: 95%, P<0.001)] and stiffness [(40% (P<0.05), 53% (P<0.05), 45% (P<0.05)]. Cement volume correlated with the compressive strength (r(2)=0.47, P<0.05) and anterior-posterior shear strength (r(2)=0.52, P<0.05) and stiffness (r(2)=0.45, P<0.05). Neither the geometry of the failed vertebrae nor its pre-fracture bone mineral density correlated with the volume of cement. Vertebral augmentation is effective in bolstering the failed lytic vertebrae compressive and axial structural competence, showing strength estimates up to 50-90% of historical values of osteoporotic vertebrae without lytic defects. This modest increase suggests that lytic vertebrae undergo a high degree of structural damage at failure, with strength only partially restored by vertebral augmentation. The positive effect of cement volume is self-limiting due to extravasation. Copyright © 2015. Published by Elsevier Ltd.

Association between human papillomavirus and Epstein - Barr virus DNA and gene promoter methylation of RB1 and CDH1 in the cervical lesions: a transversal study.

PubMed

McCormick, Thaís M; Canedo, Nathalie H S; Furtado, Yara L; Silveira, Filomena A; de Lima, Roberto J; Rosman, Andréa D F; Almeida Filho, Gutemberg L; Carvalho, Maria da Glória da C

2015-06-02

Human papillomavirus (HPV) inactivates the retinoblastoma 1 (RB1) gene by promoter methylation and reduces cellular E-cadherin expression by overexpression of DNA methyltransferase 1 (DNMT1). The Epstein-Barr virus (EBV) is an oncogenic virus that may be related to cervical carcinogenesis. In gastric cancer, it has been demonstrated that E-cadherin gene (CDH1) hypermethylation is associated with DNMT1 overexpression by EBV infection. Our aim was to analyze the gene promoter methylation frequency of RB1 and CDH1 and verify the association between that methylation frequency and HPV and EBV infection in cervical lesions. Sixty-five samples were obtained from cervical specimens: 15 normal cervices, 17 low-grade squamous intraepithelial lesions (LSIL), 15 high-grade squamous intraepithelial lesions (HSIL), and 18 cervical cancers. HPV and EBV DNA testing was performed by PCR, and the methylation status was verified by MSP. HPV frequency was associated with cervical cancer cases (p = 0.005) but not EBV frequency (p = 0.732). Viral co-infection showed a statistically significant correlation with cancer (p = 0.027). No viral infection was detected in 33.3% (5/15) of controls. RB1 methylated status was associated with cancer (p = 0.009) and HPV infection (p = 0.042). CDH1 methylation was not associated with cancer (p = 0.181). Controls and LSIL samples did not show simultaneous methylation, while both genes were methylated in 27.8% (5/18) of cancer samples. In the presence of EBV, CDH1 methylation was present in 27.8% (5/18) of cancer samples. Only cancer cases presented RB1 promoter methylation in the presence of HPV and EBV (33.3%). The methylation status of both genes increased with disease progression. With EBV, RB1 methylation was a tumor-associated event because only the cancer group presented methylated RB1 with HPV infection. HPV infection was shown to be significantly correlated with cancer conditions. The global methylation frequency was

EBV, HSV, CMV and HPV in laryngeal and oropharyngeal carcinoma in Polish patients.

PubMed

Polz-Gruszka, Dorota; Stec, Agnieszka; Dworzański, Jakub; Polz-Dacewicz, Małgorzata

2015-03-01

The role of viruses in the etiology of oral cancer has been proposed in many studies. The aim of the present study was to analyze the prevalence of Epstein-Barr virus, Human Herpes virus type 1, Cytomegalovirus and Human Papilloma virus among patients with oral squamous cell carcinoma in a Polish population. We investigated fresh-frozen tumor tissue fragments obtained from 80 patients with OSCC using the polymerase chain reaction assay. HPV was detected in 32.5% (22.5% were HPV 16), more often in laryngeal (36%) than in oropharyngeal carcinoma (26.6%). EBV was identified in 57.5%, HHV-1 in 7.5%, and CMV in 10% of patients. Co-infection with one or more viruses was detected in 30% of cases and most frequently it was co-infection with EBV and HPV (15%). Further studies are necessary to determine the potential role of EBV and the possible importance of HHV-1 as an infection co-factor in oropharyngeal cancer. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

gp140, the EBV/C3d receptor (CR2) of human B lymphocytes, is involved in cell-free phosphorylation of p120, a nuclear ribonucleoprotein.

PubMed

Delcayre, A X; Fiandino, A; Barel, M; Frade, R

1987-12-01

gp140, the EB/C3d receptor (EBV/C3dR; CR2), is a membrane site involved in human B cell regulation. Cross-linking of this receptor on the cell surface by its specific ligands led to the enhancement of B cell proliferation in synergy with T cell factors. In vitro activation of human peripheral B lymphocytes by cross-linking membrane immunoglobulins with anti-mu antibody induced EBV/C3dR phosphorylation. These studies were pursued by analyzing cell-free phosphorylation of EBV/C3dR isolated from Raji cell fractions, and immobilized on OKB7, a monoclonal anti-EBV/C3dR antibody. Three EBV/C3dR-related antigens which could be cell-free phosphorylated were detected: gp140, the EBV/C3dR, p130 and p120. gp140, the mature form of EBV/C3dR, was isolated from plasma membrane and from purified nuclei. p130 was identified as an intracellular intermediate of EBV/C3dR glycosylation, localized in low-density microsomes. Phosphoamino acid analysis of EBV/C3dR allowed the detection of phosphotyrosine and phosphoserine residues. These data suggest that EBV/C3dR could carry an autophosphorylation activity and could be associated to serine kinases. Using polyclonal anti-p120 antibody and anti-120 kDa nuclear ribonucleoprotein monoclonal antibody (mAb), p120 was identified as a nuclear ribonucleoprotein antigenically not related to EBV/C3dR. Detection of p120 on EBV/C3dR, immobilized on OKB7, was due to interactions between both antigens, instead of anti-EBV/C3dR mAb cross-reactivity with p120. Cell-free phosphorylation of p120 was under the control of EBV/C3dR. However, it is not yet established whether other nuclear or membrane components were involved in the control of p120 cell-free phosphorylation by EBV/C3dR. From the data presented herein, we propose that phosphorylation of a 120-kDa nuclear ribonucleoprotein by EBV/C3dR-associated kinases could represent a crucial step in in vivo regulation of human B cell activation.

Epstein-Barr Virus Lytic Reactivation Activates B Cells Polyclonally and Induces Activation-Induced Cytidine Deaminase Expression: A Mechanism Underlying Autoimmunity and Its Contribution to Graves' Disease.

PubMed

Nagata, Keiko; Kumata, Keisuke; Nakayama, Yuji; Satoh, Yukio; Sugihara, Hirotsugu; Hara, Sayuri; Matsushita, Michiko; Kuwamoto, Satoshi; Kato, Masako; Murakami, Ichiro; Hayashi, Kazuhiko

2017-04-01

Graves' disease is an autoimmune disease that results in and is the most common cause of hyperthyroidism, and the reactivation of persisting Epstein-Barr virus (EBV) in B lymphocytes induces the differentiation of host B cells into plasma cells. We previously reported that some EBV-infected B cells had thyrotropin receptor antibodies (TRAbs) as surface immunoglobulins (Igs), and EBV reactivation induced these TRAb+EBV+ cells to produce TRAbs. EBV reactivation induces Ig production from host B cells. The purpose of the present study was to examine total Ig productions from B cell culture fluids and to detect activation-induced cytidine deaminase (AID), nuclear factor kappa B (NF-κB), and EBV latent membrane protein (LMP) 1 in culture B cells during EBV reactivation induction and then we discussed the mechanisms of EBV reactivation-induced Ig production in relation to autoimmunity. We showed that the EBV reactivation induces the production of every isotype of Ig and suggested that the Ig production was catalyzed by AID through LMP1 and NF-κB. The results that the amount of IgM was significantly larger compared with IgG suggested the polyclonal B cell activation due to LMP1. We proposed the pathway of EBV reactivation induced Ig production; B cells newly infected with EBV are activated by polyclonal B cell activation and produce Igs through plasma cell differentiation induced by EBV reactivation. LMP1-induced AID enabled B cells to undergo class-switch recombination to produce every isotype of Ig. According to this mechanism, EBV rescues autoreactive B cells to produce autoantibodies, which contribute to the development and exacerbation of autoimmune diseases.

Epstein–Barr Virus Lytic Reactivation Activates B Cells Polyclonally and Induces Activation-Induced Cytidine Deaminase Expression: A Mechanism Underlying Autoimmunity and Its Contribution to Graves' Disease

PubMed Central

Kumata, Keisuke; Nakayama, Yuji; Satoh, Yukio; Sugihara, Hirotsugu; Hara, Sayuri; Matsushita, Michiko; Kuwamoto, Satoshi; Kato, Masako; Murakami, Ichiro; Hayashi, Kazuhiko

2017-01-01

Abstract Graves' disease is an autoimmune disease that results in and is the most common cause of hyperthyroidism, and the reactivation of persisting Epstein–Barr virus (EBV) in B lymphocytes induces the differentiation of host B cells into plasma cells. We previously reported that some EBV-infected B cells had thyrotropin receptor antibodies (TRAbs) as surface immunoglobulins (Igs), and EBV reactivation induced these TRAb+EBV+ cells to produce TRAbs. EBV reactivation induces Ig production from host B cells. The purpose of the present study was to examine total Ig productions from B cell culture fluids and to detect activation-induced cytidine deaminase (AID), nuclear factor kappa B (NF-κB), and EBV latent membrane protein (LMP) 1 in culture B cells during EBV reactivation induction and then we discussed the mechanisms of EBV reactivation-induced Ig production in relation to autoimmunity. We showed that the EBV reactivation induces the production of every isotype of Ig and suggested that the Ig production was catalyzed by AID through LMP1 and NF-κB. The results that the amount of IgM was significantly larger compared with IgG suggested the polyclonal B cell activation due to LMP1. We proposed the pathway of EBV reactivation induced Ig production; B cells newly infected with EBV are activated by polyclonal B cell activation and produce Igs through plasma cell differentiation induced by EBV reactivation. LMP1-induced AID enabled B cells to undergo class-switch recombination to produce every isotype of Ig. According to this mechanism, EBV rescues autoreactive B cells to produce autoantibodies, which contribute to the development and exacerbation of autoimmune diseases. PMID:28333576

Mutations Inactivating Herpes Simplex Virus 1 MicroRNA miR-H2 Do Not Detectably Increase ICP0 Gene Expression in Infected Cultured Cells or Mouse Trigeminal Ganglia.

PubMed

Pan, Dongli; Pesola, Jean M; Li, Gang; McCarron, Seamus; Coen, Donald M

2017-01-15

Herpes simplex virus 1 (HSV-1) latency entails the repression of productive ("lytic") gene expression. An attractive hypothesis to explain some of this repression involves inhibition of the expression of ICP0, a lytic gene activator, by a viral microRNA, miR-H2, which is completely complementary to ICP0 mRNA. To test this hypothesis, we engineered mutations that disrupt miR-H2 without affecting ICP0 in HSV-1. The mutant virus exhibited drastically reduced expression of miR-H2 but showed wild-type levels of infectious virus production and no increase in ICP0 expression in lytically infected cells, which is consistent with the weak expression of miR-H2 relative to the level of ICP0 mRNA in that setting. Following corneal inoculation of mice, the mutant was not significantly different from wild-type virus in terms of infectious virus production in the trigeminal ganglia during acute infection, mouse mortality, or the rate of reactivation from explanted latently infected ganglia. Critically, the mutant was indistinguishable from wild-type virus for the expression of ICP0 and other lytic genes in acutely and latently infected mouse trigeminal ganglia. The latter result may be related to miR-H2 being less effective in inhibiting ICP0 expression in transfection assays than a host microRNA, miR-138, which has previously been shown to inhibit lytic gene expression in infected ganglia by targeting ICP0 mRNA. Additionally, transfected miR-138 reduced lytic gene expression in infected cells more effectively than miR-H2. While this study provides little support for the hypothesis that miR-H2 promotes latency by inhibiting ICP0 expression, the possibility remains that miR-H2 might target other genes during latency. Herpes simplex virus 1 (HSV-1), which causes a variety of diseases, can establish lifelong latent infections from which virus can reactivate to cause recurrent disease. Latency is the most biologically interesting and clinically vexing feature of the virus. Ever since

Phenoloxidase but not lytic activity reflects resistance against Pasteuria ramosa in Daphnia magna

PubMed Central

Pauwels, Kevin; De Meester, Luc; Decaestecker, Ellen; Stoks, Robby

2011-01-01

The field of ecological immunology strongly relies on indicators of immunocompetence. Two major indicators in invertebrates, the activity of phenoloxidase (PO) and lytic activity have recently been questioned in studies showing that, across a natural range of baseline levels, these indicators did not predict resistance against a manipulated challenge with natural parasites. We confirmed this finding by showing that baseline levels of PO and lytic activity in the host Daphnia magna were not related to spore load of the parasite Pasteuria ramosa. Yet, PO levels in infected hosts did predict spore load, indicating PO activity can be useful as an indicator of immunocompetence in this model parasite–host system. PMID:20810432

Phenoloxidase but not lytic activity reflects resistance against Pasteuria ramosa in Daphnia magna.

PubMed

Pauwels, Kevin; De Meester, Luc; Decaestecker, Ellen; Stoks, Robby

2011-02-23

The field of ecological immunology strongly relies on indicators of immunocompetence. Two major indicators in invertebrates, the activity of phenoloxidase (PO) and lytic activity have recently been questioned in studies showing that, across a natural range of baseline levels, these indicators did not predict resistance against a manipulated challenge with natural parasites. We confirmed this finding by showing that baseline levels of PO and lytic activity in the host Daphnia magna were not related to spore load of the parasite Pasteuria ramosa. Yet, PO levels in infected hosts did predict spore load, indicating PO activity can be useful as an indicator of immunocompetence in this model parasite-host system.

A gene expression signature that correlates with CD8+T cell expansion in acute Epstein Barr virus infection1

PubMed Central

Greenough, Thomas C.; Straubhaar, Juerg R.; Kamga, Larisa; Weiss, Eric R.; Brody, Robin M.; McManus, Margaret M.; Lambrecht, Linda K.; Somasundaran, Mohan; Luzuriaga, Katherine F.

2015-01-01

Virus specific CD8+ T cells expand dramatically during acute Epstein Barr virus (EBV) infection, and their persistence is important for lifelong control of EBV-related disease. To better define the generation and maintenance of these effective CD8+ T cell responses, we used microarrays to characterize gene expression in total and EBV-specific CD8+ T cells isolated from the peripheral blood of ten individuals followed from acute infectious mononucleosis (AIM) into convalescence (CONV). In total CD8+ T cells, differential expression of genes in AIM and CONV was most pronounced among those encoding proteins important in T cell activation/differentiation, cell division/metabolism, chemokines/cytokines and receptors, signaling and transcription factors (TF), immune effector functions, and negative regulators. Within these categories, we identified 28 genes that correlated with CD8+ T cell expansion in response to an acute EBV infection. In EBV-specific CD8+ T cells, we identified 33 genes that were differentially expressed in AIM and CONV. Two important TF, T-bet and Eomesodermin (Eomes), were upregulated and maintained at similar levels in both AIM and CONV; by contrast, protein expression declined from AIM to CONV. Expression of these TF varied among cells with different epitope specificities. Altogether, gene and protein expression patterns suggest that a large proportion, if not a majority of CD8+ T cells in AIM are virus-specific, activated, dividing, and primed to exert effector activities. High expression of T-bet and Eomes may help to maintain effector mechanisms in activated cells, and to enable proliferation and transition to earlier differentiation states in CONV. PMID:26416268

Massive intracerebral Epstein-Barr virus reactivation in lethal multiple sclerosis relapse after natalizumab withdrawal.

PubMed

Serafini, Barbara; Scorsi, Eleonora; Rosicarelli, Barbara; Rigau, Valérie; Thouvenot, Eric; Aloisi, Francesca

2017-06-15

Rebound of disease activity in multiple sclerosis patients after natalizumab withdrawal is a potentially life-threatening event. To verify whether highly destructive inflammation after natalizumab withdrawal is associated with Epstein-Barr virus (EBV) reactivation in central nervous system infiltrating B-lineage cells and cytotoxic immunity, we analyzed post-mortem brain tissue from a patient who died during a fulminating MS relapse following natalizumab withdrawal. Numerous EBV infected B cells/plasma cells and CD8+ T cells infiltrated all white matter lesions; the highest frequency of EBV lytically infected cells and granzyme B+ CD8+ T cells was observed in actively demyelinating lesions. These results may encourage switching to B-cell depleting therapy after natalizumab discontinuation. Copyright © 2017 Elsevier B.V. All rights reserved.

Diagnostic dilemma: Epstein-Barr virus (EBV) infectious mononucleosis with lung involvement or co-infection with Legionnaire's disease?

PubMed

Cunha, Burke A; Gian, John

Hospitalized adults with fever and "pneumonia" can be a difficult diagnostic challenge particularly when the clinical findings may be due to different infectious diseases. We recently had an elderly female who presented with fever, fatigue and dry cough with elevated serum transaminases and lung infiltrates. The diagnosis of Epstein-Barr virus (EBV) infectious mononucleosis (IM) was made based on a positive Monospot test, elevated EBV VCA IgM titer, and highly elevated EBV viral load. Her chest infiltrates were not accompanied by hilar adenopathy which may occur with EBV IM. Her dry cough persisted and she developed abdominal pain. Legionnaire's disease was considered because she had extra-pulmonary findings characteristic of Legionnaire's disease, e.g., relative bradycardia, abdominal pain, hyponatremia, hypophosphatemia, elevated ferritin levels, microscopic hematuria. Legionella titers were negative, but Legionella (serogroup 1) urinary antigen was positive. We present a diagnostic dilemma in an elderly female with both Legionnaire's disease and Epstein-Barr virus infectious mononucleosis with pulmonary involvement. Copyright © 2016 Elsevier Inc. All rights reserved.

Concurrent targeting of EP1/EP4 receptors and COX-2 induces synergistic apoptosis in KSHV and EBV associated non-Hodgkin lymphoma cell lines

PubMed Central

Paul, Arun George; Chandran, Bala; Sharma-Walia, Neelam

2014-01-01

The effective anti-tumorigenic potential of non-steroidal anti-inflammatory drugs (NSAIDs) and eicosonoid (EP; EP1–4) receptor antagonists prompted us to test their efficacy in Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) related lymphomas. Our study demonstrated that (1) EP1–4 receptor protein levels vary among the various non-Hodgkin’s lymphoma (NHL) cell lines tested (BCBL-1:KSHV+/EBV−;BC-3: KSHV+/EBV−; Akata/EBV+: KSHV−/EBV+; and JSC-1 cells: KSHV+/EBV+ cells); (2) 5.0 µM of EP1 antagonist (SC-51322) had a significant anti-proliferative effect on BCBL-1, BC-3, Akata/EBV+, and JSC-1 cells; (3) 50.0 µM of EP2 antagonist (AH6809) was required to induce a significant anti-proliferative effect on BCBL-1, Akata/EBV+, and JSC-1 cells; (4) 5.0 µM of EP4 antagonist (GW 627368X) had a significant anti-proliferative effect on BC-3, Akata/EBV+, and JSC-1 cells; (5) COX-2 selective inhibitor celecoxib (5.0µM) had significant anti-proliferative effects on BCBL-1, BC-3, Akata/EBV+, and JSC-1 cells; and (6) a combination of 1.0µM each of celecoxib, SC-51322 and GW 627368X could potentiate the pro-apoptotic properties of celecoxib or vice-versa. Overall, our studies identified the synergistic anti-proliferative effect of NSAIDs and EP receptor blockers on KSHV and EBV related B cell malignancies. PMID:23523954

Clinicopathological analysis of 12 patients with Epstein-Barr virus-positive primary intestinal T/natural killer-cell lymphoma (EBV+ ITNKL).

PubMed

Hu, Lei-Ming; Takata, Katsuyoshi; Miyata-Takata, Tomoko; Asano, Naoko; Takahashi, Emiko; Furukawa, Katsuya; Miyoshi, Hiroaki; Satou, Akira; Kohno, Kei; Kosugi, Hiroshi; Kinoshita, Tomohiro; Hirooka, Yoshiki; Goto, Hidemi; Nakamura, Shigeo; Kato, Seiichi

2017-06-01

Epstein-Barr virus-positive (EBV + ) intestinal T/natural killer (NK) cell lymphoma (ITNKL) is an uncommon tumour with an extremely aggressive clinical behaviour. However, the clinicopathological characteristics of this tumour, including T cell receptor (TCR) phenotype and the patient's background, remain unknown. The aim of this study was to elucidate the detailed clinicopathological profile of EBV + ITNKL. We enrolled 12 patients with EBV + ITNKL without nasal involvement into the study. All patients were characterized by involvement of the small intestine with concurrent lesions of the large intestine in two patients. Seven patients (58%) had Lugano stages IIE/IV disease and eight (67%) were categorized as high-intermediate/high-risk according to the Prognostic Index for PTCL (PIT). Three patients (25%) with an age of onset of less than 50 years had chronic active EBV infection (CAEBV). Five CD56-positive patients (42%) had a poorer prognosis than those without CD56 expression (P = 0.008). NK cell-type lymphoma defined by the absence of any TCR expression or clonal TCR-γ rearrangement was found in six patients (50%). Interestingly, EBV + intra-epithelial lymphocytosis was observed in one case with a background of CAEBV. This study is the first to shed light on the significant heterogeneity of EBV + ITNKL and its relationship with CAEBV, especially in patients younger than 50 years of age. These observations will provide a guide for diagnostic and therapeutic approaches in routine practice. © 2017 John Wiley & Sons Ltd.

An animal model for human EBV-associated hemophagocytic syndrome: herpesvirus papio frequently induces fatal lymphoproliferative disorders with hemophagocytic syndrome in rabbits.

PubMed

Hayashi, K; Ohara, N; Teramoto, N; Onoda, S; Chen, H L; Oka, T; Kondo, E; Yoshino, T; Takahashi, K; Yates, J; Akagi, T

2001-04-01

Epstein-Barr virus-associated hemophagocytic syndrome (EBV-AHS) is often associated with fatal infectious mononucleosis. However, the animal model for EBV-AHS has not been developed. We reported the first animal model for EBV-AHS using rabbits infected with EBV-related herpesvirus of baboon (HVP). Eleven of 13 (85%) rabbits inoculated intravenously with HVP-producing cells developed fatal lymphoproliferative disorders (LPD) between 22 and 105 days after inoculation. LPD was also accompanied by hemophagocytic syndrome (HPS) in nine of these 11 rabbits. The peroral spray of cell-free HVP induced the virus infection with increased anti-EBV-viral capsid antigen-IgG titers in three of five rabbits, and two of these three infected rabbits died of LPD with HPS. Autopsy revealed hepatosplenomegaly and swollen lymph nodes. Atypical lymphoid T cells expressing EBV-encoded small RNA-1 infiltrated diffusely in many organs, frequently involving the lymph nodes, spleen, and liver. Hemophagocytic histiocytosis was observed in the lymph nodes, spleen, bone marrow, and thymus. HVP-DNA was detected in the tissues and peripheral blood from the infected rabbits by polymerase chain reaction or Southern blot analysis. Reverse transcriptase-polymerase chain reaction revealed both HVP-EBNA1 and HVP-EBNA2 transcripts, suggesting latency type III infection. These data indicate that the high rate of rabbit LPD with HPS induction is caused by HVP. This system is useful for studying the pathogenesis, prevention, and treatment of human EBV-AHS.

A possible link between the Epstein-Barr virus infection and autoimmune thyroid disorders

PubMed Central

Gwizdek, Katarzyna; Michalski, Marek; Wojnicz, Romuald

2016-01-01

The Epstein-Barr virus (EBV), also known as human herpesvirus 4, is a member of the Herpesviridae virus family. EBV infection can cause infectious mononucleosis (IM) in the lytic phase of EBV’s life cycle. Past EBV infection is associated with lymphomas, and may also result in certain allergic and autoimmune diseases. Although potential mechanisms of autoimmune diseases have not been clearly elucidated, both genetic and environmental factors, such as infectious agents, are considered to be responsible for their development. In addition, EBV modifies the host immune response. The worldwide prevalence of autoimmune diseases shows how common this pathogen is. Normally, the virus stays in the body and remains dormant throughout life. However, this is not always the case, and a serious EBV-related illness may develop later in life. This explains the chronic course of autoimmune diseases that is often accompanied by exacerbations of symptoms. Based on the present studies, EBV infection can cause autoimmune diseases, such as systemic lupus erythematosus (SLE), multiple sclerosis (MS), rheumatoid arthritis (RA), Sjögren’s syndrome, and autoimmune hepatitis. The EBV has also been reported in patients with autoimmune thyroid disorders. Although EBV is not the only agent responsible for the development of autoimmune thyroid diseases, it can be considered a contributory factor. PMID:27833448

Cellular corepressor TLE2 inhibits replication-and-transcription- activator-mediated transactivation and lytic reactivation of Kaposi's sarcoma-associated herpesvirus.

PubMed

He, Zhiheng; Liu, Yunhua; Liang, Deguang; Wang, Zhuo; Robertson, Erle S; Lan, Ke

2010-02-01

Replication and transcription activator (RTA) encoded by open reading frame 50 (ORF50) of Kaposi's sarcoma-associated herpesvirus (KSHV) is essential and sufficient to initiate lytic reactivation. RTA activates its target genes through direct binding with high affinity to its responsive elements or by interaction with cellular factors, such as RBP-Jkappa, Ap-1, C/EBP-alpha, and Oct-1. In this study, we identified transducin-like enhancer of split 2 (TLE2) as a novel RTA binding protein by using yeast two-hybrid screening of a human spleen cDNA library. The interaction between TLE2 and RTA was confirmed by glutathione S-transferase (GST) binding and coimmunoprecipitation assays. Immunofluorescence analysis showed that TLE2 and RTA were colocalized in the same nuclear compartment in KSHV-infected cells. This interaction recruited TLE2 to RTA bound to its recognition sites on DNA and repressed RTA auto-activation and transactivation activity. Moreover, TLE2 also inhibited the induction of lytic replication and virion production driven by RTA. We further showed that the Q (Gln-rich), SP (Ser-Pro-rich), and WDR (Trp-Asp repeat) domains of TLE2 and the Pro-rich domain of RTA were essential for this interaction. RBP-Jkappa has been shown previously to bind to the same Pro-rich domain of RTA, and this binding can be subject to competition by TLE2. In addition, TLE2 can form a complex with RTA to access the cognate DNA sequence of the RTA-responsive element at different promoters. Intriguingly, the transcription level of TLE2 could be upregulated by RTA during the lytic reactivation process. In conclusion, we identified a new RTA binding protein, TLE2, and demonstrated that TLE2 inhibited replication and transactivation mediated by RTA. This provides another potentially important mechanism for maintenance of KSHV viral latency through interaction with a host protein.

MicroRNAs sequencing unveils distinct molecular subgroups of plasmablastic lymphoma

PubMed Central

Gazaneo, Sara; Picciolini, Matteo; Vara, Prasad Satya; Sayed, Shaheen; Ginori, Alessandro; Lo Bello, Giuseppe; Del Porro, Leonardo; Navari, Mohsen; Ascani, Stefano; Yonis, Amhed; Leoncini, Lorenzo

2017-01-01

Plasmablastic lymphoma (PBL) is an aggressive lymphoma, often arising in the context of immunodeficiency and associated with Epstein-Barr virus (EBV) infection. The most frequently detected genetic alteration is the deregulation of MYC gene through the translocation - t(8;14)(q24;q32). The diagnosis of PBL is often challenging because it has an overlap in morphology, immunophenotype, cytogenetics and virus association with other lymphomas and plasma cell neoplasms; further, its molecular basis remains elusive. In the present study we aimed to better define the possible contribution of EBV infection as well as miRNA deregulation in PBL pathogenesis. We studied 23 cases of PBL, 19 Burkitt lymphomas (BL), and 17 extra-medullary plasmacytoma (EMPC). We used qPCR and immunohistochemistry to assess EBV latency patterns, while micro-RNA (miRNA) profiling was performed by next generation sequencing (Illumina) and validated by qPCR. Our analysis revealed a non-canonical EBV latency program with the partial expression of some proteins characterizing latency II and the activation of an abortive lytic cycle. Moreover, we identified miRNA signatures discriminating PBL from BL and EMPC. Interestingly, based on the miRNA profile, PBL appeared constituted by two discrete subgroups more similar to either BL or EMPC, respectively. This pattern was confirmed in an independent set of cases studied by qPCR and corresponded to different clinico-pathological features in the two groups, including HIV infection, MYC rearrangement and disease localization. In conclusion, we uncovered for the first time 1) an atypical EBV latency program in PBL; 2) a miRNA signature distinguishing PBL from the closest malignant counterparts; 3) the molecular basis of PBL heterogeneity. PMID:29296171

MicroRNAs sequencing unveils distinct molecular subgroups of plasmablastic lymphoma.

PubMed

Ambrosio, Maria Raffaella; Mundo, Lucia; Gazaneo, Sara; Picciolini, Matteo; Vara, Prasad Satya; Sayed, Shaheen; Ginori, Alessandro; Lo Bello, Giuseppe; Del Porro, Leonardo; Navari, Mohsen; Ascani, Stefano; Yonis, Amhed; Leoncini, Lorenzo; Piccaluga, Pier Paolo; Lazzi, Stefano

2017-12-08

Plasmablastic lymphoma (PBL) is an aggressive lymphoma, often arising in the context of immunodeficiency and associated with Epstein-Barr virus (EBV) infection. The most frequently detected genetic alteration is the deregulation of MYC gene through the translocation - t(8;14)(q24;q32). The diagnosis of PBL is often challenging because it has an overlap in morphology, immunophenotype, cytogenetics and virus association with other lymphomas and plasma cell neoplasms; further, its molecular basis remains elusive. In the present study we aimed to better define the possible contribution of EBV infection as well as miRNA deregulation in PBL pathogenesis. We studied 23 cases of PBL, 19 Burkitt lymphomas (BL), and 17 extra-medullary plasmacytoma (EMPC). We used qPCR and immunohistochemistry to assess EBV latency patterns, while micro-RNA (miRNA) profiling was performed by next generation sequencing (Illumina) and validated by qPCR. Our analysis revealed a non-canonical EBV latency program with the partial expression of some proteins characterizing latency II and the activation of an abortive lytic cycle. Moreover, we identified miRNA signatures discriminating PBL from BL and EMPC. Interestingly, based on the miRNA profile, PBL appeared constituted by two discrete subgroups more similar to either BL or EMPC, respectively. This pattern was confirmed in an independent set of cases studied by qPCR and corresponded to different clinico-pathological features in the two groups, including HIV infection, MYC rearrangement and disease localization. In conclusion, we uncovered for the first time 1) an atypical EBV latency program in PBL; 2) a miRNA signature distinguishing PBL from the closest malignant counterparts; 3) the molecular basis of PBL heterogeneity.

EBV-Negative Monomorphic B-Cell Posttransplant Lymphoproliferative Disorder with Marked Morphologic Pleomorphism and Pathogenic Mutations in ASXL1, BCOR, CDKN2A, NF1, and TP53.

PubMed

Bogusz, Agata M

2017-01-01

Posttransplant lymphoproliferative disorders (PTLDs) are a diverse group of lymphoid or plasmacytic proliferations frequently driven by Epstein-Barr virus (EBV). EBV-negative PTLDs appear to represent a distinct entity. This report describes an unusual case of a 33-year-old woman that developed a monomorphic EBV-negative PTLD consistent with diffuse large B-cell lymphoma (DLBCL) 13 years after heart-lung transplant. Histological examination revealed marked pleomorphism of the malignant cells including nodular areas reminiscent of classical Hodgkin lymphoma (cHL) with abundant large, bizarre Hodgkin-like cells. By immunostaining, the malignant cells were immunoreactive for CD45, CD20, CD79a, PAX5, BCL6, MUM1, and p53 and negative for CD15, CD30, latent membrane protein 1 (LMP1), and EBV-encoded RNA (EBER). Flow cytometry demonstrated lambda light chain restricted CD5 and CD10 negative B-cells. Fluorescence in situ hybridization studies (FISH) were negative for cMYC , BCL2, and BCL6 rearrangements but showed deletion of TP53 and monosomy of chromosome 17. Next-generation sequencing studies (NGS) revealed numerous genetic alterations including 6 pathogenic mutations in ASXL1, BCOR, CDKN2A, NF1, and TP53 (x2) genes and 30 variants of unknown significance (VOUS) in ABL1, ASXL1, ATM, BCOR, BCORL1, BRNIP3, CDH2, CDKN2A, DNMT3A, ETV6, EZH2, FBXW7, KIT, NF1, RUNX1, SETPB1, SF1, SMC1A, STAG2, TET2, TP53, and U2AF2.

EBV-Negative Monomorphic B-Cell Posttransplant Lymphoproliferative Disorder with Marked Morphologic Pleomorphism and Pathogenic Mutations in ASXL1, BCOR, CDKN2A, NF1, and TP53