Previous Article | Next Article 
Journal of Virology, February 1999, p. 1630-1636, Vol. 73, No. 2
0022-538X/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
Expression of Epstein-Barr Virus Nuclear Antigen 1 Is Associated with Enhanced Expression of CD25 in the Hodgkin Cell
Line L428
D.
Kube,1,2,*
M.
Vockerodt,1,2
O.
Weber,3
K.
Hell,4
J.
Wolf,1
B.
Haier,1
F. A.
Grässer,5
N.
Müller-Lantzsch,5
E.
Kieff,6
V.
Diehl,1 and
H.
Tesch1
Klinik für Innere Medizin
I,1
Zentrum für Molekulare Medizin
der Universität Köln,2 and
Institut für Pathologie der Universität
Köln,4 Cologne,
Institut für
Virologie der Universität Homburg,
Homburg,5 and
Bayer AG,
Wuppertal,3 Germany, and
Department of
Medicine and Microbiology and Molecular Genetics, Harvard Medical
School, Boston, Massachusetts6
Received 30 June 1998/Accepted 20 October 1998
 |
ABSTRACT |
Epstein-Barr virus is associated with several human malignancies
including Burkitt's lymphoma, nasopharyngeal carcinoma, and Hodgkin's
disease (HD). To examine the effect of Epstein-Barr virus nuclear
antigen 1 (EBNA-1) in the pathogenesis of HD, we transfected the gene
into the HD cell line L428. EBNA-1 expression was associated with
significantly enhanced CD25 expression (interleukin 2 [IL-2]-receptor
chain) in transient and stably transfected L428 cells but did not
affect the expression of IL-2 receptor
and
chains. There was no
up-regulation of the B-cell activation molecules CD23, CD30, CD39,
CD40, CD44, CD71, and CD54 (intercellular adhesion molecule 1) or
enhanced production of IL-6, IL-10, lymphotoxin alpha, and the soluble
form of CD25. Stable EBNA-1-expressing L428 cells were nontumorigenic
in SCID mice but showed enhanced lymphoma development in nonobese
diabetic-SCID mice compared to mock-transfected cells.
 |
TEXT |
Hodgkin's disease (HD) is
characterized by a disruption of the lymph node architecture with low
numbers of Hodgkin and Reed-Sternberg (H-RS) cells surrounded by an
abundance of reactive nonmalignant cells (2, 9, 13, 26).
This histological pattern of HD is probably due to the production and
release of cytokines by H-RS cells which are involved in the biology of
HD (19).
In HD, Epstein-Barr virus (EBV) is present in more than 50% of cases
and has been suggested to be a critical element in the pathogenesis of
the disease (1, 7, 12, 23, 36). Epidemiological studies
first indicated a link between EBV and HD and showed an increased risk
of developing HD in patients with infectious mononucleosis and elevated
EBV-VCA titers. More direct evidence came from molecular studies, which
demonstrated the presence of EBV sequences and antigens in H-RS cells
(2, 12, 33). The latent membrane protein 1 (LMP-1) is
detectable in H-RS cells in the absence of the EBV nuclear antigen 2 (EBNA-2), which can transactivate LMP-1 and a subset of cellular genes
in B cells (3, 35). Both EBNA-1 and LMP-2A were also found
to be expressed in H-RS cells by immunostaining (7, 11, 24).
EBV is involved in the pathogenesis of a number of different human
tumors, including immunoblastic B-cell lymphomas of immunocompromised patients, endemic Burkitt's lymphoma, certain T-cell lymphomas, and
nasopharyngeal carcinoma (NPC) (2, 6, 26). All
EBV-associated tumor cells carry episomal copies of the EBV genome, and
the EBER genes (small untranslated nonpolyadenylated nuclear viral
RNAs) are abundantly expressed. The precise role of EBV in tumor
development may be different in each disease, and a different
expression pattern of viral genes can be observed in the tumor cells.
The least complex case involves immunoblastic B-cell lymphomas, where
tumor cell growth appears to be directly EBV driven in a manner
analogous to that of the lymphoblastoid cell lines (LCLs) that arise
when EBV infects normal resting B cells in vitro or in the absence of a
functional immune system. Other EBV-associated tumors show a more
restricted pattern of viral gene expression limited to EBNA-1 in
Burkitt's lymphoma only (known as latency type I) or to EBNA-1, LMP-1,
and LMP-2A expression in HD and NPC (defined as latency type II)
(26).
EBNA-1 is the only latent protein consistently expressed in all
EBV-bearing tumor cells. Previously, it has been shown that a
subpopulation of B lymphocytes express EBNA-1 mRNA in the absence of
EBNA-2 or LMP-1, suggesting that the expression pattern of EBV genes in
lymphoma cells of latency type I is the same as that in normal B cells.
This expression pattern reflects a strategy of EBV of persisting in a
latent state while being unrecognized by immunosurveillance
(5). It has been shown that EBNA-1 does not alter the
phenotype of stably transfected BJAB lymphoma cells (35),
but transgenic mice expressing EBNA-1 specifically in B cells develop
B-cell lymphomas (39). The role of EBNA-1 in HD is not clear yet.
We analyzed the effects of EBNA-1 on cell morphology, cell surface
antigen, cytokine expression, and tumorigenicity in the HD cell line
L428. L428 represents a cell line of B-cell origin and is characterized
by the expression of many different surface antigens such as CD30,
CD39, CD40, CD44, CD54 (intercellular adhesion molecule 1 [ICAM-1]),
CD58 (lymphocyte function-associated antigen 3 [LFA3]), CD70, CD71,
CD80 (B7.BB1), and major histocompatibility complex class II molecules.
L428 cells are not tumorigenic in immunodeficient nude or SCID mice
(9, 34). The cells constitutively express a number of
cytokines including tumor necrosis factor alpha, lymphotoxin alpha
(LT-
), granulocyte-macrophage colony-stimulating factor, and
interleukin 6 (IL-6) (19, 30). Furthermore, L428 cells carry
rearranged immunoglobulin (Ig) heavy-chain and Ig light-chain genes.
Sequence analysis revealed that the rearranged VH gene (VH5) is
characterized by a high number of somatic mutations. Clonally related,
highly mutated rearranged Ig genes have also been detected by
single-cell analyses in most cases of primary HD (16). This
indicates that the L428 H-RS cell, like primary H-RS cells, has
probably undergone a complex maturation and differentiation process
within the germinal center, where the transformation process may have
occurred. This cell line provides a useful model system for analyzing
the effect of EBNA-1 gene expression in HD. Therefore, we transfected
the EBNA-1 gene in the HD cell line L428 and selected a number of
EBNA-1-positive cell clones.
Transfection of EBNA-1 in L428 cells.
To obtain stable
EBNA-1-expressing cells, L428 cells were cotransfected with pSG5 EBNA-1
expression plasmid or pSG5 vector control and a plasmid coding for
puromycin-N-acetyltransferase with an electroporator
(Easy-Ject electroporator; Eurogentec, Seraing, Belgium). After
transfection, cells were grown under puromycin selection and 60 resistant clones were analyzed for EBNA-1 expression. A total of 15 independent EBNA-1-positive clones and 12 control clones (pSG5 vector)
were included in this analysis from three independent transfection
experiments. EBNA-1 expression was detected by immunoblotting with an
EBNA-1-specific antibody (11) and the enhanced
chemiluminescence (ECL) detection kit (Amersham Life Science,
Braunschweig, Germany). As depicted in Fig.
1A, the stably transfected L428 clones
are characterized by different levels of EBNA-1 expression (indicated
by "++" to "++++"), with up to 15-fold-higher levels of EBNA-1
compared to the LCL IARC 304 (Fig. 1B). EBNA-1 was detected over a
period of more than 12 months.

View larger version (24K):
[in this window]
[in a new window]
|
FIG. 1.
Immunoblot of EBNA-1 expression in L428 cells (A) and
LCL 304 (B). The immunoblots were probed with rat anti-EBNA-1 (1H4)
monoclonal antibody. (A) Representative vector control (pSG5-pSV-PAC)
L428 clones and pSG5-EBNA-1-pSV-PAC-expressing L428 clones are shown.
mutu cl59 was used as a positive control. Expression levels of EBNA-1
are indicated by "++" to "++++," on a scale of one to four plus
signs. (B) Comparison of EBNA-1 expression levels in EBNA-1-positive
L428 clones and in the EBV-infected LCL IARC 304. Numbers at left
indicate molecular mass in kilodaltons.
|
|
To analyze the function of EBNA-1 in HD cells, EBNA-1-expressing and
vector control L428 clones derived from independent transfections were
assayed (i) morphologically; (ii) for the expression of B-lymphocyte activation markers (CD23, CD39, CD44, and CD71), the IL-2 receptor (IL-2R) complex (CD25-IL-2R
, CD122-IL-2R
, and p65
chains), molecules of the tumor necrosis factor-nerve growth factor
receptor-ligand family (CD30 and CD40), and the cell adhesion molecule
CD54-ICAM-1 by flow cytometry; (iii) for cytokine expression; and (iv)
for tumorigenicity in SCID and nonobese diabetic (NOD)-SCID mice.
Expression of cellular surface antigens.
Analysis of cell
surface antigens was performed by flow cytometry with the
FACScan (Becton Dickinson, Heidelberg, Germany). Values are
presented as specific mean linear fluorescence intensities after
subtraction of background staining with isotype-matched control. Dead
cells were excluded by propidium-iodide staining. The following
monoclonal antibodies were used in this study: IgG1 fluorescein
isothiocyanate (FITC)-phycoerythrin (PE), IgG2A FITC, anti-CD23-PE-low-affinity Fc
receptor, anti-CD25-PE-IL-2R
chain, anti-CD54-PE-ICAM-1, and goat anti-mouse Ig-FITC (Becton Dickinson, BDIS, San Jose, Calif.); anti-CD39, anti-CD40-FITC, anti-CD122-PE-IL-2R
chain, and anti-IL-2R
chain-PE
(Pharmingen, San Diego, Calif.); anti-CD44 (R&D Systems, Abingdon,
United Kingdom); anti-CD30-FITC (Dako, Glostrup, Denmark); anti-CD4-PE
and anti-CD71-FITC-transferrin receptor (Immunotech, Marseille,
France). Table 1 summarizes the results
of the surface immunofluorescence analyses of five representative
EBNA-1-expressing and vector control-fluorescein isothiocyanate
(FITC)-phycoerythrin (PE), transfected clones. No changes were found in
the expression of the B-cell activation markers CD23, CD39, CD44, and
CD71 and the cell adhesion molecule CD54. All analyzed clones showed
low levels of CD23 and CD39 expression, while CD44, CD54, and CD71 were
constitutively expressed at high levels without further significant
alterations. CD30 and CD40, characteristic surface antigens in most
cases of HD and HD-derived cell lines and constitutively expressed in
L428 cells, were not affected by EBNA-1 expression.
Induction of CD25 by EBNA-1.
As shown in Table
2, the expression of EBNA-1 is associated
with a consistent enhanced CD25 expression, compared with CD25 levels
in vector control cells. The CD25 expression level on
vector-transfected cells ranged from 0.2 to 2.0 with an average mean
fluorescence level of 1. In the case of EBNA-1-expressing L428 cells,
the expression level of CD25 ranged from 0.2 to 33.8. These cell clones
could be divided into two subgroups. Five of fifteen EBNA-1-expressing cell clones were characterized by CD25 expression levels which were
comparable to that of control vector-transfected cells (mean fluorescence, 0.2, 0.9, 1.2, 1.6, and 2.0). However, 10 of 15 EBNA-1-expressing L428 clones showed CD25 expression levels which were
higher than those in mock-transfected cells. There was a statistically
significant difference between CD25 expression levels in
EBNA-1-expressing cells and those in control clones as shown by the
Mann-Whitney test (P = 0.001). One EBNA-1-positive
clone (L428E1P MG5) showed a high level of EBNA-1 expression without significant CD25 expression. This could have been due to secondary effects during cell culture. However, the enhanced CD25 surface level
correlated in the majority of clones with the level of EBNA-1 expression.
View this table:
[in this window]
[in a new window]
|
TABLE 2.
Expression of CD25 in L428 cells expressing EBNA-1 in
correlation with the expression level of EBNA-1 in
early passagesa
|
|
To determine whether L428 cells expressed the high-affinity IL-2R
complex consisting of the
chain (CD25), the
chain (CD122), and
the p65
chain, we performed surface immunofluorescence stainings for these antigens. EBNA-1-positive and vector control clones showed
low staining for the
chain, while the p65
chain was constitutively expressed in all L428 clones (Fig.
2A). Since the expression of the
chain and the p65
chain of the IL-2R in L428 cells was not altered
by EBNA-1, this further underlined the specific effect of EBNA-1 on
CD25 expression. To determine whether the increase on the CD25 surface
level was associated with changes in IL-2R
-chain mRNA levels, total
cellular RNA from different transfected clones was analyzed by
semiquantitative reverse transcription-PCR (RT-PCR) as previously
described (37). L428 cells expressing EBNA-1 contained
increased IL-2R
-chain mRNA levels compared with vector control
cells (Fig. 2B).

View larger version (42K):
[in this window]
[in a new window]
|
FIG. 2.
Expression of IL-2R molecules in L428 cells expressing
EBNA-1. (A) Surface phenotype analysis of L428 clones for CD25-IL-2R
chain (a), CD122-IL-2R chain (b), and IL-2R chain (c).
EBNA-1-expressing L428 cells or vector control cells were stained with
isotype controls and corresponding PE-conjugated antibodies directed
against CD25, CD122, and IL-2 chain. Vector control cells were
stained with isotype control (dashed outline and no shading) or with
specific antibody (solid outline and no shading). EBNA-1-expressing
clones were stained with isotype control (solid outline with shading)
or with specific antibody (shading and no outline). In this analysis,
the clones L428KoP N6 and L428E1P F1 were used. (B) Seminquantitative
RT-PCR of total RNA isolated from L428 cells expressing EBNA-1 or
vector-transfected control cells. RNA was reverse transcribed, and
defined increasing amounts of cDNA were amplified with both
glyceraldehyde-3-phosphate dehydrogenase (GAPDH)-specific
oligonucleotides to normalize the amount of cDNA and IL-2R
-chain-specific oligonucleotides. In both reactions, a control
vector at fixed amounts carrying synthetic binding sites for
glyceraldehyde-3-phosphate dehydrogenase-IL-2R -chain
oligonucleotides was included (37). For this analysis,
clones L428KoP N1, L428KoP N6, L428E1P F1, L428E1P E1, and L428E1P F4
were used (see also Table 2).
|
|
CD25 activation by EBNA-1 in L428 cells was also analyzed in a
transient assay to confirm that the up-regulation of CD25 was EBNA-1
specific. After cotransfection of pMACS 4.1 (which encodes the
extracellular domain of CD4 as a selection antigen) and pSG5 or
pSG5-EBNA-1, we enriched transfected cells through immunomagnetic separation of CD4-positive cells with a magnetic cell sorting (MACS)
system (Miltenyi Biotec, Bergisch Gladbach, Germany). Our results
demonstrate that EBNA-1-positive cells express CD25 at up to
twofold-higher levels than do mock-transfected L428 cells (Fig.
3). This upregulation of CD25 by EBNA-1
in L428 cells was maximal at 120 h after magnetic sorting.

View larger version (40K):
[in this window]
[in a new window]
|
FIG. 3.
Expression of CD25 on the cell surface of
transient-transfected L428 cells with EBNA-1 (shaded bars) or vector
control (unshaded bars) and pMACS4.1 after MACS separation. The
fraction of CD25-positive cells was evaluated 24, 96, and 120 h
after MACS separation. A representative experiment of three independent
transfection experiments and MACS enrichments is shown.
|
|
The high levels of CD25 antigen on stable EBNA-1-expressing cells were
lost during prolonged cultivation of transfected cells even when the
EBNA-1 expression was unchanged in these clones and the cells were
grown under permanent selection (Table
3). Therefore, increased CD25 levels in
short-time-cultivated stably EBNA-1-expressing cells might reflect a
high activation status of these cells. The loss of enhanced CD25
expression suggests a selection process in cell culture which may be
directed against the expression of EBNA-1-induced genes. Another
possibility is an enhanced shedding of CD25. It has been reported
elsewhere that CD25 can be shed from the cell surface and can be
detected in serum of HD patients and NPC patients (10, 15).
Therefore, we analyzed soluble CD25 in cell culture supernatants by
enzyme-linked immunosorbent assay (Amersham Life Science). No soluble
CD25 was detected in the supernatants of EBNA-1-positive cells,
revealing that the activation of CD25 by EBNA-1 and following
subsequent decrease of surface CD25 was not associated with increased
levels of soluble CD25 in the supernatants (data not shown).
This EBNA-1-associated up-regulation of CD25 implies the possibility of
IL-2 binding to L428 cells expressing this EBV gene and activating
them. To analyze whether IL-2 can preferentially stimulate
EBNA-1-positive L428 cells, the cells were incubated with and without
recombinant human IL-2 (100 U/ml) (Gibco Life Technologies) for up to
96 h. [3H]thymidine incorporation revealed no effect
of IL-2 on the proliferation of EBNA-1-positive or -negative L428
cells, while freshly isolated T cells proliferated after addition of
IL-2 (data not shown). Since the IL-2R
chain was expressed at low
levels in all L428 cell clones analyzed, the effect of IL-2 on the
EBNA-1-expressing L428 cells is probably mediated only as a
low-affinity signal (14, 19), so that signals of IL-2 are
possibly nonmitogenic.
Cytokine activation by EBNA-1.
It has been shown that HD cell
lines express a large number of cytokines (14, 19, 29, 30).
To investigate whether EBNA-1 can influence cytokine expression, we
analyzed the expression of IL-6, IL-10, and LT-
by semiquantitative
RT-PCR and enzyme-linked immunosorbent assay. In some but not all
EBNA-1-positive clones (5 of 15), enhanced production of IL-6 was
detected (800 pg/ml within 48 h compared to 150 pg/ml produced by
the control cells), which reveals no direct involvement of EBNA-1. No
significant changes were observed for IL-10 (negative) and LT-
(unchanged high-level expression), which are induced by EBV in
Burkitt's lymphoma (14, 20).
Enhanced lymphoma growth by L428 cells transfected with EBNA-1 in
mice.
The parental cell line L428 is nontumorigenic in SCID mice
(34). To test the influence of EBNA-1 on the tumorigenicity
of L428 cells, 107 cells of EBNA-1 and control transfected
L428 cells were injected intraperitoneally into five SCID mice. Mice
were sacrificed after 10 weeks. No tumor growth was detected at this
time and even when the mice were kept for longer times. However, with
NOD-SCID mice 5 of 15 animals developed lymphomas within 5 weeks when
EBNA-1-positive cells were inoculated, whereas with vector
control-transfected L428 cells no lymphoma development was observed (0 of 15 animals analyzed). In addition, L428 cells expressing LMP-1 (0 of
5 animals analyzed) or EBNA-2 (0 of 5 animals analyzed) did not cause
tumor growth in NOD-SCID mice.
The lymphomas that developed from EBNA-1-expressing L428 cells were
characterized by a diffuse infiltration in various organs (pancreas,
liver, bowel, kidney, skin, and muscle) (Fig.
4a) with characteristics of H-RS cells,
and many mitotic and apoptotic cells were present; however, the
bystander cell population typical for HD was missing due to the absence
of T and B cells in the mice. Immunohistochemical examination revealed
a high CD30 expression on the lymphoma cells (Fig. 4b). Our result
indicates that EBNA-1 can promote lymphoma growth in this animal
system. The enhanced tumorigenicity of EBNA-1-positive L428 cells is
compatible with results obtained in a transgenic mouse model where it
was shown that the expression of EBNA-1 in B cells induces malignant
B-cell lymphomas (39).

View larger version (150K):
[in this window]
[in a new window]
|
FIG. 4.
Lymphoma in NOD-SCID mice developed within 5 weeks after
injection of EBNA-1-expressing L428 cells (L428E1P F1). (a) Lymphoma
developed in the pancreas of a NOD-SCID mouse. The infiltrate has a
sharp border towards the pancreas (magnification, ×100). (b) Tissue
sections were stained for expression of the HD-associated antigen CD30,
showing a strong expression on the cell surface (magnification,
×600).
|
|
These findings suggest that EBNA-1 is able to modulate the expression
of surface antigens and to enhance tumorigenicity in H-RS cells. CD25
levels were increased in EBNA-1-expressing cells, although IL-2 did not
affect cell proliferation. Similar findings have been described for
B-cell chronic lymphocytic leukemia, where the neoplastic cells
expressed only the IL-2R
chain (CD25), while the
chain was only
weakly expressed in a few cases (8, 17, 32). In addition,
the proliferative response of chronic lymphocytic leukemia cells in the
presence of even high doses of IL-2 is low (8). The
activation of CD25 in malignant cells may have different functions
compared to that in T cells, where IL-2 induces proliferation and
promotes expression of its own receptor (4, 17). It has been
reported elsewhere that direct activation of the protein kinase C or
protein kinase A pathway leads to an induction of CD25 in high-density
tonsillar B cells (22). We have shown previously that
treatment of L428 cells with phorbol myristate acetate leads to an
induction of CD25 antigen expression and reflects a strong activation
of these cells (29). Thus, CD25 induction could
be a secondary effect caused by EBNA-1 expression in L428 cells
by a still-unknown pathway (27). The up-regulation of CD25
by EBNA-1 in L428 cells may have important functional significance, and
the established EBNA-1-expressing L428 cells provide a new tool to
analyze this question in more detail. We and others have shown
previously that primary H-RS cells regularly express CD25, which
indicates that this molecule might be involved in the biology of HD
(31). EBNA-1 is expressed in a high proportion of
EBV-positive HD cases in the H-RS cells and may play an important role
in the pathogenesis of HD (11, 18, 25). Whether CD25
expression on primary H-RS cells is correlated with the presence of
EBNA-1 in these cells has to be investigated.
The observed tumorigenicity of L428 cells after EBNA-1 transfection is
compatible with results obtained in a transgenic mouse model where it
was shown that the expression of EBNA-1 in B cells induced malignant
B-cell lymphomas, frequently of follicular-center cell origin
(39), demonstrating a tumorigenic potential for EBNA-1.
However, the expression level of EBNA-1 detected in L428 cells in vitro
was up to 15-fold higher than that in the LCL, suggesting that a high
level of EBNA-1 is needed to induce phenotypic changes or tumor growth.
In addition, primary H-RS cells and HD cell lines represent in most
cases a population of germinal-center B cells with a high degree of
preactivation of surface antigens and cytokine expression and thus
represent a different status of activation compared to Burkitt's
lymphoma cells. When expressed in Burkitt's lymphoma, EBNA-1 has no
effects on the surface phenotype, while the expression of the
recombinase-activating genes RAG1 and RAG2 seems to be associated with
EBNA-1 expression in some but not all analyzed Burkitt's lymphoma
lines. In the Burkitt's-like lymphoma line BJAB or in different LCLs,
RAG1 and RAG2 expression was not detected (21, 28). Thus,
the effects of EBNA-1 are probably different in several cell types,
depending on the differentiation stage and the preactivation of the
cells (38).
The description of these specific effects of EBNA-1 on HD cells now
provides an opportunity to dissect the mechanism by which EBV alters
gene expression in HD and thus may contribute to the transformation and
immune escape mechanisms of the transformed H-RS cells.
 |
ACKNOWLEDGMENTS |
We acknowledge J. Franklin for help in the statistical analysis,
J. B. Wilson for helpful discussions of the manuscript, and U. Meyer and H. Straub for technical assistance.
This work was supported by the Deutsche Forschungsgemeinschaft by a
grant through the Sonderforschungsbereich 502.
 |
FOOTNOTES |
*
Corresponding author. Present address:
Universität Tübingen, Institut für Tropenmedizin
Sektion Humanparasitologie, Wilhelmstrasse 27, D-72074 Tübingen,
Germany. Phone: 49 7071 2980 240. Fax: 49 7071 295189. E-mail:
ail14{at}pop.rrz.uni-koeln.de.
 |
REFERENCES |
| 1.
|
Anagnostopoulos, I.,
H. Herbst,
G. Niedobitek, and H. Stein.
1989.
Demonstration of monoclonal EBV genomes in Hodgkin's disease and Ki-1-positive anaplastic large cell lymphoma by combined Southern blot and in situ hybridization.
Blood
74:810-816[Abstract/Free Full Text].
|
| 2.
|
Anagnostopoulos, I.,
M. Hummel, and H. Stein.
1996.
Epstein-Barr virus and Hodgkin's disease.
Forum. Trends Exp. Clin. Med.
6:36-50.
|
| 3.
|
Armstrong, A. A.,
L. M. Weiss,
A. Gallagher,
D. B. Jones,
A. S. Krajewski,
B. Angus,
G. Brown,
A. S. Jack,
B. S. Wilkins,
D. E. Onions, et al.
1992.
Criteria for the definition of Epstein-Barr virus association in Hodgkin's disease.
Leukemia
6:869-874[Medline].
|
| 4.
|
Burton, J., and N. E. Kay.
1994.
Does IL-2 receptor expression and secretion in chronic B-cell leukemia have a role in down-regulation of the immune system?
Leukemia
8:92-96[Medline].
|
| 5.
|
Chen, F.,
J. Z. Zou,
L. di Renzo,
G. Winberg,
L. F. Hu,
E. Klein,
G. Klein, and I. Ernberg.
1995.
A subpopulation of normal B cells latently infected with Epstein-Barr virus resembles Burkitt lymphoma cells in expressing EBNA-1 but not EBNA-2 or LMP1.
J. Virol.
69:3752-3758[Abstract].
|
| 6.
| Cruchley, A. T., D. M. Williams, G. Niedobitek, and L. S. Young. 1997. Epstein-Barr virus:
biology and disease. Oral Dis. 3(Suppl.
1):156-163.
|
| 7.
|
Deacon, E. M.,
G. Pallesen,
G. Niedobitek,
J. Crocker,
L. Brooks,
A. B. Rickinson, and L. S. Young.
1993.
Epstein-Barr virus and Hodgkin's disease: transcriptional analysis of virus latency in the malignant cells.
J. Exp. Med.
177:339-349[Abstract/Free Full Text].
|
| 8.
|
deTotero, D.,
C. P. di Francia,
A. Cignetti, and R. Foa.
1995.
The IL-2 receptor complex: expression and function on normal and leukemic B cells.
Leukemia
9:1425-1431[Medline].
|
| 9.
|
Diehl, V.,
H. H. Kirchner,
M. Schaadt,
C. Fonatsch,
H. Stein,
J. Gerdes, and C. Boie.
1981.
Hodgkin's disease: establishment and characterization of four in vitro cell lines.
J. Cancer Res. Clin. Oncol.
101:111-124[Medline].
|
| 10.
|
Gorschluter, M.,
H. Bohlen,
D. Hasenclever,
V. Diehl, and H. Tesch.
1995.
Serum cytokine levels correlate with clinical parameters in Hodgkin's disease.
Ann. Oncol.
6:477-482[Abstract/Free Full Text].
|
| 11.
|
Grasser, F.,
P. G. Murray,
E. Kremmer,
K. Klein,
K. Remberger,
W. Feiden,
G. Reynolds,
G. Niedobitek,
L. S. Young, and L. N. Mueller.
1994.
Monoclonal antibodies directed against the Epstein-Barr virus-encoded nuclear antigen 1 (EBNA-1): immunohistologic detection of EBNA-1 in the malignant cells of Hodgkin's disease.
Blood
84:3792-3978[Abstract/Free Full Text].
|
| 12.
|
Herbst, H.,
F. Dallenbach,
M. Hummel,
G. Niedobitek,
S. Pileri,
L. N. Muller, and H. Stein.
1991.
Epstein-Barr virus latent membrane protein expression in Hodgkin and Reed-Sternberg cells.
Proc. Natl. Acad. Sci. USA
88:4766-4770[Abstract/Free Full Text].
|
| 13.
|
Herbst, H.,
T. Raff, and H. Stein.
1996.
Phenotypic modulation of Hodgkin and Reed-Sternberg cells by Epstein-Barr virus.
J. Pathol.
179:54-59[Medline].
|
| 14.
|
Herbst, H.,
H. D. Foss,
J. Samol,
I. Araujo,
H. Klotzbach,
H. Krause,
A. Agathanggelou,
G. Niedobitek, and H. Stein.
1996.
Frequent expression of interleukin-10 by Epstein-Barr virus-harboring tumor cells of Hodgkin's disease.
Blood
87:2918-2929[Abstract/Free Full Text].
|
| 15.
|
Hsu, M. M.,
Y. J. Chen,
Y. L. Chang,
J. Y. Ko, and T. S. Sheen.
1995.
Soluble interleukin-2 receptor as a clinical parameter for nasopharyngeal carcinoma.
Asian Pac. J. Allergy Immunol.
13:1-4[Medline].
|
| 16.
|
Kanzler, H.,
R. Kuppers,
M. L. Hansmann, and K. Rajewsky.
1996.
Hodgkin and Reed-Sternberg cells in Hodgkin's disease represent the outgrowth of a dominant tumor clone derived from (crippled) germinal center B cells.
J. Exp. Med.
184:1495-1505[Abstract/Free Full Text].
|
| 17.
|
Karnitz, L. M., and R. T. Abraham.
1996.
Interleukin-2 receptor signaling mechanisms.
Adv. Immunol.
61:147-199[Medline].
|
| 18.
|
Khan, G., and M. A. Naase.
1995.
Down-regulation of Epstein-Barr virus nuclear antigen 1 in Reed-Sternberg cells of Hodgkin's disease.
J. Clin. Pathol.
48:845-848[Abstract/Free Full Text].
|
| 19.
|
Klein, S.,
M. Jucker,
V. Diehl, and H. Tesch.
1992.
Production of multiple cytokines by Hodgkin's disease derived cell lines.
Hematol. Oncol.
10:319-329[Medline].
|
| 20.
|
Klein, S. C.,
D. Kube,
H. Abts,
V. Diehl, and H. Tesch.
1996.
Promotion of IL8, IL10, TNF alpha and TNF beta production by EBV infection.
Leuk. Res.
20:633-636[Medline].
|
| 21.
|
Kuhn, H. I.,
D. R. Sage,
L. Stein,
H. Groelle, and J. D. Fingeroth.
1995.
Expression of recombination activating genes (RAG-1 and RAG-2) in Epstein-Barr virus-bearing B cells.
Blood
85:1289-1299[Abstract/Free Full Text].
|
| 22.
|
McKay, C. E., and W. Cushley.
1996.
Induction of CD25 expression in human B lymphocytes by pharmacological activators of cellular signalling pathways.
Cytokine
8:305-312[Medline].
|
| 23.
|
Mueller, N.
1987.
Epidemiologic studies assessing the role of the Epstein-Barr virus in Hodgkin's disease.
Yale J. Biol. Med.
60:321-332[Medline].
|
| 24.
|
Niedobitek, G.,
E. Kremmer,
H. Herbst,
L. Whitehead,
C. W. Dawson,
E. Niedobitek,
C. von Ostau,
N. Rooney,
F. A. Grasser, and L. S. Young.
1997.
Immunohistochemical detection of the Epstein-Barr virus-encoded latent membrane protein 2A in Hodgkin's disease and infectious mononucleosis.
Blood
90:1664-1672[Abstract/Free Full Text].
|
| 25.
|
Oudejans, J. J.,
D. F. Dukers,
N. M. Jiwa,
A. J. van den Brule,
F. A. Grasser,
P. C. de Bruin,
A. Horstman,
W. Vos,
J. van Gorp,
J. M. Middeldorp, and C. J. Meijer.
1996.
Expression of Epstein-Barr virus encoded nuclear antigen 1 in benign and malignant tissues harbouring EBV.
J. Clin. Pathol.
49:897-902[Abstract/Free Full Text].
|
| 26.
|
Rickinson, A., and E. Kieff.
1996.
Biology of EBV, p. 2397-2446.
In
B. N. Fields, D. M. Knipe, P. M. Howley, et al. (ed.), Fields virology. Lippincott-Raven, New York, N.Y.
|
| 27.
|
Snudden, D. K.,
J. Hearing,
P. R. Smith,
F. A. Grasser, and B. E. Griffin.
1994.
EBNA-1, the major nuclear antigen of Epstein-Barr virus, resembles 'RGG' RNA binding proteins.
EMBO J.
13:4840-4847[Medline].
|
| 28.
|
Srinivas, S. K., and J. W. Sixbey.
1995.
Epstein-Barr virus induction of recombinase-activating genes RAG1 and RAG2.
J. Virol.
69:8155-8158[Abstract].
|
| 29.
|
Tesch, H.,
M. Jucker,
S. Klein,
H. Abts,
A. Gunther,
G. R. Krueger, and V. Diehl.
1992.
Hodgkin and Reed-Sternberg cells express interleukin 6 and interleukin 6 receptors.
Leuk. Lymphoma
7:297-303[Medline].
|
| 30.
|
Tesch, H.,
A. C. Feller,
M. Jucker,
S. Klein,
H. Merz, and V. Diehl.
1992.
Activation of cytokines in Hodgkin's disease.
Ann. Oncol.
4:13-16.
|
| 31.
|
Tesch, H.,
A. Gunther,
H. Abts,
M. Jucker,
S. Klein,
G. R. Krueger, and V. Diehl.
1993.
Expression of interleukin-2R alpha and interleukin-2R beta in Hodgkin's disease.
Am. J. Pathol.
142:1714-1720[Abstract].
|
| 32.
|
Tsilivakos, V.,
A. Tsapis,
S. Kakolyris,
P. Iliakis,
M. Perraki, and V. Georgoulias.
1994.
Characterization of interleukin 2 receptors on B-cell chronic lymphocytic leukemia cells.
Leukemia
8:1571-1578[Medline].
|
| 33.
|
Vasef, M. A.,
O. W. Kamel,
Y. Y. Chen,
L. J. Medeiros, and L. M. Weiss.
1995.
Detection of Epstein-Barr virus in multiple sites involved by Hodgkin's disease.
Am. J. Pathol.
147:1408-1415[Abstract].
|
| 34.
|
von Kalle, C.,
J. Wolf,
A. Becker,
A. Scaer,
M. Munck,
A. Engert,
U. Kapp,
C. Fonatsch,
D. Komitowski,
W. Fe'aux Delacroix, and V. Diehl.
1992.
Growth of Hodgkin's cell lines in severly combined immunodeficient mice.
Int. J. Cancer
52:887-891[Medline].
|
| 35.
|
Wang, F.,
C. Gregory,
C. Sample,
M. Rowe,
D. Liebowitz,
R. Murray,
A. Rickinson, and E. Kieff.
1990.
Epstein-Barr virus latent membrane protein (LMP1) and nuclear proteins 2 and 3C are effectors of phenotypic changes in B lymphocytes: EBNA-2 and LMP1 cooperatively induce CD23.
J. Virol.
64:2309-2318[Abstract/Free Full Text].
|
| 36.
|
Weiss, L. M., and K. L. Chang.
1992.
Molecular biologic studies of Hodgkin's disease.
Semin. Diagn. Pathol.
9:272-278[Medline].
|
| 37.
|
Westermann, F.,
D. Kube,
B. Haier,
H. Bohlen,
A. Engert,
M. Zuehlsdorf,
V. Diehl, and H. Tesch.
1996.
Interleukin 10 inhibits cytokine production of human AML cells.
Ann. Oncol.
7:397-404[Abstract/Free Full Text].
|
| 38.
|
Willerford, D. M.,
J. Chen,
J. A. Ferry,
L. Davidson,
A. Ma, and F. W. Alt.
1995.
Interleukin-2 receptor alpha chain regulates the size and content of the peripheral lymphoid compartment.
Immunity
3:521-530[Medline].
|
| 39.
|
Wilson, J. B.,
J. L. Bell, and A. J. Levine.
1996.
Expression of Epstein-Barr virus nuclear antigen-1 induces B cell neoplasia in transgenic mice.
EMBO J.
15:3117-3126[Medline].
|
Journal of Virology, February 1999, p. 1630-1636, Vol. 73, No. 2
0022-538X/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
This article has been cited by other articles:
-
Flavell, J. R., Baumforth, K. R. N., Wood, V. H. J., Davies, G. L., Wei, W., Reynolds, G. M., Morgan, S., Boyce, A., Kelly, G. L., Young, L. S., Murray, P. G.
(2008). Down-regulation of the TGF-beta target gene, PTPRK, by the Epstein-Barr virus encoded EBNA1 contributes to the growth and survival of Hodgkin lymphoma cells. Blood
111: 292-301
[Abstract]
[Full Text]
-
Pages, F., Galon, J., Karaschuk, G., Dudziak, D., Camus, M., Lazar, V., Camilleri-Broet, S., Lagorce-Pages, C., Lebel-Binay, S., Laux, G., Fridman, W.-H., Henglein, B.
(2005). Epstein-Barr virus nuclear antigen 2 induces interleukin-18 receptor expression in B cells. Blood
105: 1632-1639
[Abstract]
[Full Text]
-
Kang, M.-S., Lu, H., Yasui, T., Sharpe, A., Warren, H., Cahir-McFarland, E., Bronson, R., Hung, S. C., Kieff, E.
(2005). Epstein-Barr virus nuclear antigen 1 does not induce lymphoma in transgenic FVB mice. Proc. Natl. Acad. Sci. USA
102: 820-825
[Abstract]
[Full Text]
-
Lu, C.-C., Wu, C.-W., Chang, S. C., Chen, T.-Y., Hu, C.-R., Yeh, M.-Y., Chen, J.-Y., Chen, M.-R.
(2004). Epstein-Barr virus nuclear antigen 1 is a DNA-binding protein with strong RNA-binding activity. J. Gen. Virol.
85: 2755-2765
[Abstract]
[Full Text]
-
Humme, S., Reisbach, G., Feederle, R., Delecluse, H.-J., Bousset, K., Hammerschmidt, W., Schepers, A.
(2003). The EBV nuclear antigen 1 (EBNA1) enhances B cell immortalization several thousandfold. Proc. Natl. Acad. Sci. USA
100: 10989-10994
[Abstract]
[Full Text]
-
Ito, S., Gotoh, E., Ozawa, S., Yanagi, K.
(2002). Epstein-Barr virus nuclear antigen-1 is highly colocalized with interphase chromatin and its newly replicated regions in particular. J. Gen. Virol.
83: 2377-2383
[Abstract]
[Full Text]
-
Paludan, C., Bickham, K., Nikiforow, S., Tsang, M. L., Goodman, K., Hanekom, W. A., Fonteneau, J.-F., Stevanovic, S., Munz, C.
(2002). Epstein-Barr Nuclear Antigen 1-Specific CD4+ Th1 Cells Kill Burkitt's Lymphoma Cells. J. Immunol.
169: 1593-1603
[Abstract]
[Full Text]
-
Wu, H., Kapoor, P., Frappier, L.
(2002). Separation of the DNA Replication, Segregation, and Transcriptional Activation Functions of Epstein-Barr Nuclear Antigen 1. J. Virol.
76: 2480-2490
[Abstract]
[Full Text]
-
Kang, M.-S., Hung, S. C., Kieff, E.
(2001). Epstein-Barr virus nuclear antigen 1 activates transcription from episomal but not integrated DNA and does not alter lymphocyte growth. Proc. Natl. Acad. Sci. USA
10.1073/pnas.211556598v1
[Abstract]
[Full Text]
-
Kube, D., Holtick, U., Vockerodt, M., Ahmadi, T., Haier, B., Behrmann, I., Heinrich, P. C., Diehl, V., Tesch, H.
(2001). STAT3 is constitutively activated in Hodgkin cell lines. Blood
98: 762-770
[Abstract]
[Full Text]
-
Ruf, I. K., Rhyne, P. W., Yang, C., Cleveland, J. L., Sample, J. T.
(2000). Epstein-Barr Virus Small RNAs Potentiate Tumorigenicity of Burkitt Lymphoma Cells Independently of an Effect on Apoptosis. J. Virol.
74: 10223-10228
[Abstract]
[Full Text]
-
Ruf, I. K., Sample, J.
(1999). Repression of Epstein-Barr Virus EBNA-1 Gene Transcription by pRb during Restricted Latency. J. Virol.
73: 7943-7951
[Abstract]
[Full Text]
-
Kang, M.-S., Hung, S. C., Kieff, E.
(2001). Epstein-Barr virus nuclear antigen 1 activates transcription from episomal but not integrated DNA and does not alter lymphocyte growth. Proc. Natl. Acad. Sci. USA
98: 15233-15238
[Abstract]
[Full Text]