Non-correlation of in vivo and in vitro parameters of Epstein-Barr virus persistence suggests heterogeneity of B cell infection.

ABSTRACT The human gammaherpesviruses Epstein-Barr virus and Kaposi Sarcoma-associated herpesvirus both contain a glycoprotein (gp350/220 and K8.1, respectively) that mediates binding to target cells and has been studied in great detail in vitro. However, there is no direct information on the role that these glycoproteins play in pathogenesis in vivo. Infection of mice by murid herpesvirus 4 strain 68 (MHV-68) is an established animal model for gammaherpesvirus pathogenesis and expresses an analogous glycoprotein, gp150. To elucidate the in vivo function of gp150, a recombinant MHV-68 deficient in gp150 production was generated (vgp150Δ). The productive viral replication in vitro and in vivo was largely unaffected by mutation of gp150, aside from a partial defect in the release of extracellular virus. Likewise, B-cell latency was established. However, the transient mononucleosis and spike in latently infected cells associated with the spread of MHV-68 to the spleen was significantly reduced in vgp150Δ-infected mice. A soluble, recombinant gp150 was found to bind specifically to B cells but not to epithelial cells in culture. In addition, gp150-deficient MHV-68 derived from mouse lungs bound less well to spleen cells than wild-type virus. Thus, gp150 is highly similar in function in vitro to the Epstein-Barr virus gp350/220. These results suggest a role for these analogous proteins in mononucleosis and have implications for their use as vaccine antigens.

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Epstein-Barr Virus LMP2A Alters In Vivo and In Vitro Models of B-Cell Anergy, but Not Deletion, in Response to Autoantigen

Journal of Virology ◽

10.1128/jvi.79.12.7355-7362.2005 ◽

2005 ◽

Vol 79 (12) ◽

pp. 7355-7362 ◽

Cited By ~ 39

Author(s):

Michelle A. Swanson-Mungerson ◽

Robert G. Caldwell ◽

Rebecca Bultema ◽

Richard Longnecker

Keyword(s):

B Cells ◽

B Cell ◽

Epstein Barr Virus ◽

Nuclear Translocation ◽

Cell Receptor ◽

Barr Virus ◽

Low Levels ◽

Epstein Barr

ABSTRACT A significant percentage of the population latently harbors Epstein-Barr virus (EBV) in B cells. One EBV-encoded protein, latent membrane protein 2A (LMP2A), is expressed in tissue culture models of EBV latent infection, in human infections, and in many of the EBV-associated proliferative disorders. LMP2A constitutively activates proteins involved in the B-cell receptor (BCR) signal transduction cascade and inhibits the antigen-induced activation of these proteins. In the present study, we investigated whether LMP2A alters B-cell receptor signaling in primary B cells in vivo and in vitro. LMP2A does not inhibit antigen-induced tolerance in response to strong stimuli in an in vivo tolerance model in which B cells are reactive to self-antigen. In contrast, LMP2A bypasses anergy induction in response to low levels of soluble hen egg lysozyme (HEL) both in vivo and in vitro as determined by the ability of LMP2A-expressing HEL-specific B cells to proliferate and induce NF-κB nuclear translocation after exposure to low levels of antigen. Furthermore, LMP2A induces NF-κB nuclear translocation independent of BCR cross-linking. Since NF-κB is required to bypass tolerance induction, this LMP2A-dependent NF-κB activation may complete the tolerogenic signal induced by low levels of soluble HEL. Overall, the findings suggest that LMP2A may not inhibit BCR-induced signals under all conditions as previously suggested by studies with EBV immortalized B cells.

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Molecular virology of Epstein–Barr virus

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2000.0781 ◽

2001 ◽

Vol 356 (1408) ◽

pp. 437-459 ◽

Cited By ~ 99

Author(s):

Georg W. Bornkamm ◽

Wolfgang Hammerschmidt

Keyword(s):

B Cell ◽

Epstein Barr Virus ◽

Descriptive Analysis ◽

Genetic System ◽

Lytic Cycle ◽

Barr Virus ◽

Cell Immortalization ◽

Epstein Barr

Epstein–Barr virus (EBV) interacts with its host in three distinct ways in a highly regulated fashion: (i) EBV infects human B lymphocytes and induces proliferation of the infected cells, (ii) it enters into a latent phase in vivo that follows the proliferative phase, and (iii) it can be reactivated giving rise to the production of infectious progeny for reinfection of cells of the same type or transmission of the virus to another individual. In healthy people, these processes take place simultaneously in different anatomical and functional compartments and are linked to each other in a highly dynamic steady–state equilibrium. The development of a genetic system has paved the way for the dissection of those processes at a molecular level that can be studied in vitro , i.e. B–cell immortalization and the lytic cycle leading to production of infectious progeny. Polymerase chain reaction analyses coupled to fluorescent–activated cell sorting has on the other hand allowed a descriptive analysis of the virus–host interaction in peripheral blood cells as well as in tonsillar B cells in vivo . This paper is aimed at compiling our present knowledge on the process of B–cell immortalization in vitro as well as in vivo latency, and attempts to integrate this knowledge into the framework of the viral life cycle in vivo .

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Virally Induced Cellular MicroRNA miR-155 Plays a Key Role in B-Cell Immortalization by Epstein-Barr Virus

Journal of Virology ◽

10.1128/jvi.01248-10 ◽

2010 ◽

Vol 84 (22) ◽

pp. 11670-11678 ◽

Cited By ~ 129

Author(s):

Sarah D. Linnstaedt ◽

Eva Gottwein ◽

Rebecca L. Skalsky ◽

Micah A. Luftig ◽

Bryan R. Cullen

Keyword(s):

B Cell ◽

Cell Lines ◽

Epstein Barr Virus ◽

B Cell Lymphoma ◽

Selective Inhibition ◽

B Cell Lymphomas ◽

Cell Infection ◽

Barr Virus ◽

Epstein Barr

ABSTRACT Infection of resting primary human B cells by Epstein-Barr virus (EBV) results in their transformation into indefinitely proliferating lymphoblastoid cell lines (LCLs). LCL formation serves as a model for lymphomagenesis, and LCLs are phenotypically similar to EBV-positive diffuse large B-cell lymphomas (DLBCLs), which represent a common AIDS-associated malignancy. B-cell infection by EBV induces the expression of several cellular microRNAs (miRNAs), most notably miR-155, which is overexpressed in many tumors and can induce B-cell lymphomas when overexpressed in animals. Here, we demonstrate that miR-155 is the most highly expressed miRNA in LCLs and that the selective inhibition of miR-155 function specifically inhibits the growth of both LCLs and the DLBCL cell line IBL-1. Cells lacking miR-155 are inefficient in progressing through S phase and spontaneously undergo apoptosis. In contrast, three other B-cell lymphoma lines, including two EBV-positive Burkitt's lymphoma cell lines, grew normally in the absence of miR-155 function. These data identify the induction of cellular miR-155 expression by EBV as critical for the growth of both laboratory-generated LCLs and naturally occurring DLBCLs and suggest that targeted inhibition of miR-155 function could represent a novel approach to the treatment of DLBCL in vivo.

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Epstein-Barr virus nuclear protein 2A forms oligomers in vitro and in vivo through a region required for B-cell transformation.

Journal of Virology ◽

10.1128/jvi.68.7.4287-4294.1994 ◽

1994 ◽

Vol 68 (7) ◽

pp. 4287-4294 ◽

Cited By ~ 13

Author(s):

S Tsui ◽

W H Schubach

Keyword(s):

B Cell ◽

Epstein Barr Virus ◽

Nuclear Protein ◽

Cell Transformation ◽

Barr Virus ◽

Epstein Barr

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Identification of the Site of Epstein-Barr Virus Persistence In Vivo as a Resting B Cell

Journal of Virology ◽

10.1128/jvi.72.11.9419-9419.1998 ◽

1998 ◽

Vol 72 (11) ◽

pp. 9419-9419 ◽

Cited By ~ 1

Author(s):

Emily M. Miyashita ◽

Bin Yang ◽

Gregory J. Babcock ◽

David A. Thorley-Lawson

Keyword(s):

B Cell ◽

Epstein Barr Virus ◽

Virus Persistence ◽

Barr Virus ◽

Epstein Barr

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Epstein-Barr Virus LMP2A Enhances B-Cell Responses In Vivo and In Vitro

Journal of Virology ◽

10.1128/jvi.00433-06 ◽

2006 ◽

Vol 80 (14) ◽

pp. 6764-6770 ◽

Cited By ~ 27

Author(s):

Michelle Swanson-Mungerson ◽

Rebecca Bultema ◽

Richard Longnecker

Keyword(s):

B Cells ◽

B Cell ◽

Epstein Barr Virus ◽

Plasma Cells ◽

Barr Virus ◽

Epstein Barr ◽

Hen Egg ◽

Hen Egg Lysozyme

ABSTRACT Epstein-Barr virus (EBV) establishes latent infections in a significant percentage of the population. Latent membrane protein 2A (LMP2A) is an EBV protein expressed during latency that inhibits B-cell receptor signaling in lymphoblastoid cell lines. In the present study, we have utilized a transgenic mouse system in which LMP2A is expressed in B cells that are specific for hen egg lysozyme (E/HEL-Tg). To determine if LMP2A allows B cells to respond to antigen, E/HEL-Tg mice were immunized with hen egg lysozyme. E/HEL-Tg mice produced antibody in response to antigen, indicating that LMP2A allows B cells to respond to antigen. In addition, E/HEL-Tg mice produced more antibody and an increased percentage of plasma cells after immunization compared to HEL-Tg littermates, suggesting that LMP2A increased the antibody response in vivo. Finally, in vitro studies determined that LMP2A acts directly on the B cell to increase antibody production by augmenting the expansion and survival of the activated B cells, as well as increasing the percentage of plasma cells generated. Taken together, these data suggest that LMP2A enhances, not diminishes, B-cell-specific antibody responses in vivo and in vitro in the E/HEL-Tg system.

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Human Epstein-Barr virus (EBV)-specific cytotoxic T lymphocytes home preferentially to and induce selective regressions of autologous EBV-induced B cell lymphoproliferations in xenografted C.B-17 scid/scid mice.

Journal of Experimental Medicine ◽

10.1084/jem.183.3.1215 ◽

1996 ◽

Vol 183 (3) ◽

pp. 1215-1228 ◽

Cited By ~ 74

Author(s):

J F Lacerda ◽

M Ladanyi ◽

D C Louie ◽

J M Fernandez ◽

E B Papadopoulos ◽

...

Keyword(s):

T Cells ◽

B Cell ◽

Epstein Barr Virus ◽

Scid Mice ◽

Barr Virus ◽

Target Ratio ◽

Epstein Barr ◽

Effector Target

C.B-17 scid/scid (severe combined immunodeficiency [SCID]) mice inoculated with peripheral blood lymphocytes from Epstein-Barr virus (EBV)-seropositive donors, or with EBV-transformed lymphoblastoid B cell lines (EBV-LCL), develop lethal human EBV+ B cell lymphoproliferative disorders (EBV-LPD) with characteristics similar to those arising in immunodeficient patients. Using this model, we examined the capacity of human effector cells to control human EBV-LPD. SCID mice received rabbit anti-asialo GM1 antiserum to abrogate endogenous natural killer-cell function. Preliminary experiments showed that adoptive transfer of peripheral blood mononuclear cells (PBMC), purified T cells, interleukin (IL) 2-activated PBMC or anti-CD3-activated T cells derived from EBV-seropositive donors did not result in improved survival of treated mice (in vivo effector/target ratio 2:1 to 1:1). In contrast, EBV-specific cytotoxic T lymphocytes (CTL), derived from EBV-seropositive donors and expanded in vitro, exhibited strong EBV-specific and HLA-restricted activity both in vitro and in vivo. SCID mice inoculated intraperitoneally with autologous but not with HLA-mismatched EBV-LCL had significantly improved survival relative to untreated mice after inoculation of EBV-specific CTL either intraperitoneally (P<0.001) or intravenously (P<0.001) (in vivo effector/target ratio 1:1). SCID mice bearing large subcutaneous EBV+ tumors and treated intravenously with 10(7) EBV-specific CTL achieved complete tumor regression. Both CTL- and CTL-plus-IL-2-treated mice survived significantly longer than untreated animals or animals treated with IL-2 alone (P = 0.0004 and P<0.02, respectively). SCID mice bearing two subcutaneous EBV+ tumors, one autologous and the other HLA mismatched to the EBV-specific CTL donor, had regression of only the autologous tumor after intravenous infusion of 10(7) EBV-specific CTL. Moreover, we could demonstrate preferential homing of PKH26-labeled EBV-specific CTL to autologous but not to HLA-mismatched EBV+ tumors as early as 24 h after intravenous adoptive transfer. Immunophenotypic analyses also demonstrated preferential infiltration of T cells into the autologous EBV+ tumor in SCID mice bearing both the autologous and either fully HLA-mismatched or genotypically related haplotype-sharing EBV+ tumors. The human T cells infiltrating EBV+ tumors were CD3+ and, predominantly, CD8+CD4-. Our results indicate that EBV-specific CTL preferentially localize to and infiltrate EBV+ tumors bearing the appropriate HLA antigens and thereafter induce targeted regressions of disease.

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How Epstein–Barr Virus and Kaposi’s Sarcoma-Associated Herpesvirus Are Maintained Together to Transform the Same B-Cell

Viruses ◽

10.3390/v13081478 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1478

Author(s):

Arthur U. Sugden ◽

Mitch Hayes ◽

Bill Sugden

Keyword(s):

B Cell ◽

Kaposi's Sarcoma ◽

Epstein Barr Virus ◽

Kaposi’S Sarcoma ◽

Barr Virus ◽

Kaposi's Sarcoma Associated Herpesvirus ◽

Epstein Barr ◽

Kaposi’S Sarcoma Associated Herpesvirus

Epstein–Barr virus (EBV) and Kaposi’s sarcoma-associated herpesvirus (KSHV) independently cause human cancers, and both are maintained as plasmids in tumor cells. They differ, however, in their mechanisms of segregation; EBV partitions its genomes quasi-faithfully, while KSHV often clusters its genomes and partitions them randomly. Both viruses can infect the same B-cell to transform it in vitro and to cause primary effusion lymphomas (PELs) in vivo. We have developed simulations based on our measurements of these replicons in B-cells transformed in vitro to elucidate the synthesis and partitioning of these two viral genomes when in the same cell. These simulations successfully capture the biology of EBV and KSHV in PELs. They have revealed that EBV and KSHV replicate and partition independently, that they both contribute selective advantages to their host cell, and that KSHV pays a penalty to cluster its genomes.

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Induction of Lytic Epstein-Barr Virus (EBV) Infection by Synergistic Action of Rituximab and Dexamethasone Renders EBV-Positive Lymphoma Cells More Susceptible to Ganciclovir Cytotoxicity In Vitro and In Vivo

Journal of Virology ◽

10.1128/jvi.79.9.5875-5879.2005 ◽

2005 ◽

Vol 79 (9) ◽

pp. 5875-5879 ◽

Cited By ~ 27

Author(s):

Masanori Daibata ◽

Kentaro Bandobashi ◽

Masayuki Kuroda ◽

Shosuke Imai ◽

Isao Miyoshi ◽

...

Keyword(s):

B Cell ◽

Epstein Barr Virus ◽

Cell Lymphoma ◽

B Cell Lymphoma ◽

Lymphoma Cells ◽

Barr Virus ◽

Ebv Infection ◽

Epstein Barr

ABSTRACT The purposeful induction of the lytic form of Epstein-Barr virus (EBV) infection combined with ganciclovir (GCV) treatment has been advocated as a novel strategy for EBV-positive B-cell lymphoma. We demonstrated that rituximab had a synergistic effect with dexamethasone on induction of the lytic EBV infection in CD20-positive lymphoma cells. Addition of GCV to the dexamethasone/rituximab-treated cells was more effective than dexamethasone/rituximab alone in killing EBV-positive lymphoma cells in vitro and in lymphoma-bearing nude mice but not in EBV-negative cells. These data suggest that induction of the lytic EBV infection with dexamethasone/rituximab in combination with GCV could be a potential virally targeted therapy for EBV-associated B-cell lymphoma.

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