Epstein-barr virus latently infected cells are selectively deleted in simulated-microgravity cultures

2001 ◽  
Vol 37 (4) ◽  
pp. 223-230 ◽  
Author(s):  
James P. Long ◽  
John H. Hughes
Keyword(s):  
Epstein Barr Virus ◽  
Simulated Microgravity ◽  
Barr Virus ◽  
Latently Infected ◽  
Infected Cells ◽  
Epstein Barr

scholarly journals Infection of Epstein–Barr Virus in Type III Latency Modulates Biogenesis of Exosomes and the Expression Profile of Exosomal miRNAs in the Burkitt Lymphoma Mutu Cell Lines

Cancers ◽  
2018 ◽  
Vol 10 (7) ◽  
pp. 237 ◽  
Author(s):  
Asuka Nanbo ◽  
Harutaka Katano ◽  
Michiyo Kataoka ◽  
Shiho Hoshina ◽  
Tsuyoshi Sekizuka ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Burkitt Lymphoma ◽  
Epstein Barr Virus ◽  
Type I ◽  
Type Iii ◽  
Barr Virus ◽  
Ebv Infection ◽  
Latently Infected ◽  
Infected Cells ◽  
Epstein Barr

Infection of Epstein–Barr virus (EBV), a ubiquitous human gamma herpesvirus, is associated with various malignancies in B lymphocytes and epithelial cells. EBV encodes 49 microRNAs in two separated regions, termed the BART and BHRF1 loci. Although accumulating evidence demonstrates that EBV infection regulates the profile of microRNAs in the cells, little is known about the microRNAs in exosomes released from infected cells. Here, we characterized the expression profile of intracellular and exosomal microRNAs in EBV-negative, and two related EBV-infected Burkitt lymphoma cell lines having type I and type III latency by next-generation sequencing. We found that the biogenesis of exosomes is upregulated in type III latently infected cells compared with EBV-negative and type I latently infected cells. We also observed that viral and several specific host microRNAs were predominantly incorporated in the exosomes released from the cells in type III latency. We confirmed that multiple viral microRNAs were transferred to the epithelial cells cocultured with EBV-infected B cells. Our findings indicate that EBV infection, in particular in type III latency, modulates the biogenesis of exosomes and the profile of exosomal microRNAs, potentially contributing to phenotypic changes in cells receiving these exosomes.

scholarly journals Nascent Transcriptomics Reveal Cellular Prolytic Factors Upregulated Upstream of the Latent-to-Lytic Switch Protein of Epstein-Barr Virus

2020 ◽  
Vol 94 (7) ◽  
Author(s):  
Tiffany R. Frey ◽  
Jozan Brathwaite ◽  
Xiaofan Li ◽  
Sandeepta Burgula ◽  
Ibukun A. Akinyemi ◽  
...  
Keyword(s):  
Epstein Barr Virus ◽  
Human Herpesvirus ◽  
Lytic Cycle ◽  
Barr Virus ◽  
Viral Spread ◽  
Cellular Genes ◽  
Latently Infected ◽  
Infected Cells ◽  
Host Shutoff ◽  
Epstein Barr

ABSTRACT Lytic activation from latency is a key transition point in the life cycle of herpesviruses. Epstein-Barr virus (EBV) is a human herpesvirus that can cause lymphomas, epithelial cancers, and other diseases, most of which require the lytic cycle. While the lytic cycle of EBV can be triggered by chemicals and immunologic ligands, the lytic cascade is activated only when expression of the EBV latent-to-lytic switch protein ZEBRA is turned on. ZEBRA then transcriptionally activates other EBV genes and, together with some of those gene products, ensures completion of the lytic cycle. However, not every latently infected cell exposed to a lytic trigger turns on the expression of ZEBRA, resulting in responsive and refractory subpopulations. What governs this dichotomy? By examining the nascent transcriptome following exposure to a lytic trigger, we find that several cellular genes are transcriptionally upregulated temporally upstream of ZEBRA. These genes regulate lytic susceptibility to various degrees in latently infected cells that respond to mechanistically distinct lytic triggers. While increased expression of these cellular genes defines a prolytic state, such upregulation also runs counter to the well-known mechanism of viral-nuclease-mediated host shutoff that is activated downstream of ZEBRA. Furthermore, a subset of upregulated cellular genes is transcriptionally repressed temporally downstream of ZEBRA, indicating an additional mode of virus-mediated host shutoff through transcriptional repression. Thus, increased transcription of a set of host genes contributes to a prolytic state that allows a subpopulation of cells to support the EBV lytic cycle. IMPORTANCE Transition from latency to the lytic phase is necessary for herpesvirus-mediated pathology as well as viral spread and persistence in the population at large. Yet, viral genomes in only some cells in a population of latently infected cells respond to lytic triggers, resulting in subpopulations of responsive/lytic and refractory cells. Our investigations into this partially permissive phenotype of the herpesvirus Epstein-Barr virus (EBV) indicate that upon exposure to lytic triggers, certain cellular genes are transcriptionally upregulated, while viral latency genes are downregulated ahead of expression of the viral latent-to-lytic switch protein. These cellular genes contribute to lytic susceptibility to various degrees. Apart from indicating that there may be a cellular “prolytic” state, our findings indicate that (i) early transcriptional upregulation of cellular genes counters the well-known viral-nuclease-mediated host shutoff and (ii) subsequent transcriptional downregulation of a subset of early upregulated cellular genes is a previously undescribed mode of host shutoff.

Calcium modulation activates Epstein-Barr virus genome in latently infected cells

Science ◽  
1986 ◽  
Vol 232 (4757) ◽  
pp. 1554-1556 ◽  
Author(s):  
A Faggioni ◽  
C Zompetta ◽  
S Grimaldi ◽  
G Barile ◽  
L Frati ◽  
...  
Keyword(s):  
Epstein Barr Virus ◽  
Virus Genome ◽  
Barr Virus ◽  
Calcium Modulation ◽  
Latently Infected ◽  
Infected Cells ◽  
Epstein Barr

scholarly journals Cells Expressing the Epstein-Barr Virus Growth Program Are Present in and Restricted to the Naive B-Cell Subset of Healthy Tonsils

2000 ◽  
Vol 74 (21) ◽  
pp. 9964-9971 ◽  
Author(s):  
Alexandra M. Joseph ◽  
Gregory J. Babcock ◽  
David A. Thorley-Lawson
Keyword(s):  
B Cells ◽  
B Cell ◽  
Epstein Barr Virus ◽  
Cell Subset ◽  
Pcr Analysis ◽  
Virus Growth ◽  
Barr Virus ◽  
Latently Infected ◽  
Infected Cells ◽  
Epstein Barr

ABSTRACT In this paper we demonstrate, for the first time, that Epstein-Barr virus (EBV)-infected cells expressing the lymphoblastoid growth program are present in healthy carriers of the virus. Previously we observed that latently infected naive B cells are present in tonsils only when viral replication is detected, suggesting that these may represent newly infected B cells. We have tested this idea by performing a reverse transcription-PCR analysis for the expression of latent genes (EBNA2 and the EBNA3s) that are characteristically expressed only by newly infected cells expressing the growth latency program. EBNA2 expression is regularly detected in purified naive (IgD+) tonsillar B cells (13 of 16 tonsils tested) but was never found in the IgD− population (0 of 16). More detailed analysis revealed that the mRNAs for the latent genes EBNA1 (3 of 3 tonsils tested), EBNA3a (3 of 5), EBNA3b (3 of 5), EBNA3c (3 of 5), LMP1 (6 of 6), and LMP2 (5 of 6) were also present in the IgD+ population, but the EBNA1Q-K transcript, characteristic of nonlymphoblastoid forms of latency, was never detected (0 of 6). Finally, we demonstrate that the latently infected naive (IgD+) cells express CD80 (B7.1), a marker characteristically expressed on activated naive lymphoblasts but absent from resting naive B cells. The infected naive (IgD+) population in the tonsil therefore has the viral and cellular phenotype of a B-cell directly infected with EBV—an activated lymphoblast expressing the growth program.

Bryostatin 1 induces productive Epstein-Barr virus replication in latently infected cells: implications for use in immunocompromised patients

1993 ◽  
Vol 33 (1) ◽  
pp. 89-91 ◽  
Author(s):  
James P. Stewart ◽  
Alan T. McGown ◽  
Joseph Prendiville ◽  
George R. Pettit ◽  
Brian W. Fox ◽  
...  
Keyword(s):  
Virus Replication ◽  
Epstein Barr Virus ◽  
Immunocompromised Patients ◽  
Bryostatin 1 ◽  
Barr Virus ◽  
Latently Infected ◽  
Infected Cells ◽  
Epstein Barr

Induction of the Epstein-Barr virus (EBV) cycle in latently infected cells by n-butyrate

Virology ◽  
1979 ◽  
Vol 94 (1) ◽  
pp. 228-231 ◽  
Author(s):  
Janos Luka ◽  
Bengt Kallin ◽  
George Klein
Keyword(s):  
Epstein Barr Virus ◽  
Barr Virus ◽  
Latently Infected ◽  
Infected Cells ◽  
Epstein Barr

scholarly journals Epstein-Barr Virus–Infected Resting Memory B Cells, Not Proliferating Lymphoblasts, Accumulate in the Peripheral Blood of Immunosuppressed Patients

1999 ◽  
Vol 190 (4) ◽  
pp. 567-576 ◽  
Author(s):  
Gregory J. Babcock ◽  
Lisa L. Decker ◽  
Richard B. Freeman ◽  
David A. Thorley-Lawson
Keyword(s):  
B Cells ◽  
Peripheral Blood ◽  
Epstein Barr Virus ◽  
Memory B Cells ◽  
Barr Virus ◽  
Latently Infected ◽  
Immunosuppressed Patients ◽  
Infected Cells ◽  
Epstein Barr ◽  
Healthy Carriers

When Epstein-Barr virus (EBV) infects B cells in vitro, the result is a proliferating lymphoblast that expresses at least nine latent proteins. It is generally believed that these cells are rigorously controlled in vivo by cytotoxic T cells. Consistent with this, the latently infected cells in the peripheral blood of healthy carriers are not lymphoblasts. Rather, they are resting memory B cells that are probably not subject to direct immunosurveillance by cytotoxic T lymphocytes (CTLs). When patients become immunosuppressed, the viral load increases in the peripheral blood. The expansion of proliferating lymphoblasts due to the suppressed CTL response is believed to account for this increase and is considered to be a major risk factor for posttransplant lymphoproliferative disease (PTLD) and AIDS-associated B cell lymphoma. Here we show that there is an increase in the numbers of latently infected cells in the peripheral blood of immunosuppressed patients. However, the cells are not proliferating lymphoblasts. They are all latently infected, resting, memory B cells—the same population of infected cells found in the blood of healthy carriers. These results are discussed in the context of a model for EBV persistence that explains why PTLD is usually limited to the lymph nodes.

Epstein-Barr virus BHRF1 prohibits the cells of nasopharyngeal carcinoma from apoptosis

1997 ◽  
Vol 111 (12) ◽  
pp. 1147-1150 ◽  
Author(s):  
H. Huang ◽  
J. H. Zhou ◽  
S. M. Zhou ◽  
J. H. Hu ◽  
X. H. Pan ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Epstein Barr Virus ◽  
Biological Behaviour ◽  
Barr Virus ◽  
Dna Damaging Agents ◽  
Before And After ◽  
Latently Infected ◽  
Infected Cells ◽  
Epstein Barr ◽  
Camptothecin Treatment

AbstractEpstein-Barr virus (EBV) is associated with nasopharyngeal carcinoma (NPC). The BHRF1 EBV protein is expressed at high levels in productively infected cells and certain latently infected cells. In order to investigate the effect of expression of BHRF1 on the biological behaviour of NPC cells, we constructed the BHRF1 high expression vector and transfected it into the NPC cell line, CNE2. Then, the alteration of proliferation and apoptotic rates in the cells were tested before and after camptothecin treatment. After treatment by camptothecin, BHRF1-CNE2cells could constantly and slowly proliferate and its apoptotic rate was less than in control groups, and the number of cells in the G phase decreased and in the S phase increased. So, it suggests that BHRF1 expression can enhance the resistibility of CNE2cells to DNA damaging agents that cause apoptosis.

Sign in / Sign up

Export Citation Format

Share Document