The Journal of Immunology, 1999, 162: 1551-1558.
Copyright © 1999 by The American Association of Immunologists
AIDS Primary Central Nervous System Lymphoma: Molecular Analysis of the Expressed VH Genes and Possible Implications for Lymphomagenesis1
Sylvie Julien*,
Mirjana Radosavljevic*,
Nathalie Labouret*,
Sophie Camilleri-Broet
,
Frederic Davi
,
Martine Raphael
,
Thierry Martin* and
Jean-Louis Pasquali2,*
*
Laboratoire dImmunopathologie, Centre de Recherche dImmunohématologie, Hôpital Civil, Hôpitaux Universitaires, Strasbourg, France; and
Service dHematologie Biologique, Hôpital Avicenne, Bobigny, France
 |
Abstract
|
|---|
AIDS-associated primary central nervous system lymphomas are late
events that have an extremely poor prognosis. Despite different
hypotheses, the brain localization of these B cell lymphomas remains an
enigma. To better define the cell origin of the lymphomas and the
possible role of the B cell receptor (BCR) in the brain localization
and/or in the oncogenic transformation, we analyzed the V region genes
of the Ig heavy chain expressed by lymphoma cells in five randomly
selected patients. After amplifying the rearranged
VHDJH DNA by PCR, cloning, and sequencing of
the amplified products, we observed that: 1) of the five lymphomas
analyzed, four were clearly monoclonal; 2) there was no preferential
use of one peculiar VH family or one peculiar
segment of gene; 3) the mutation analysis showed that an Ag-driven
process occurred in at least two cases, probably before the oncogenic
event; and 4) there was no intraclonal variability, suggesting that the
hypermutation mechanism is no longer efficient in these lymphoma B
cells. Taken together, our results suggest that distinct Ags could be
recognized by the BCR of the lymphoma cells in different patients and
that, if the Ags are responsible for the brain localization of these B
cells bearing mutated BCR, other factors must be involved in B cell
transformations in primary central nervous system
lymphoma.
 |
Introduction
|
|---|
In
the past, primary central nervous system
(CNS)3 lymphoma (PCNSL) was
considered to be a rare disease; however, its incidence increased
dramatically with the outbreak of the AIDS epidemic. It was recently
suggested that, if the incidence of PCNSL continued to increase, it
could become the most common primary malignant neoplasm of the CNS by
the year 2000 (1). The overall survival of patients with
AIDS-associated PCNSL remains extremely poor (1). Among AIDS-associated
lymphomas that are histologically fairly heterogeneous, AIDS-associated
PCNSLs have the peculiarity of a homogeneous histology, usually
presenting as large cell immunoblastic plasmocytoid lymphomas of the B
lymphocyte lineage (2, 3).
The origins of HIV-associated lymphomas have not been clearly
elucidated; however, different factors may contribute to the occurrence
of these B cell neoplasias (reviewed in 4 , including EBV,
immunodeficiency, chronic antigenic stimulation leading to B cell
hyperactivity, and genetic lesions. Focusing on PCNSL, the causative
factor EBV is consistently found during PCNSL within the lymphoma cells
(5), which is not the case during the heterogeneous systemic
AIDS-associated lymphomas. Furthermore, AIDS-associated PCNSLs express
Epstein-Barr nuclear Ag-2 and latent membrane protein-1, which
are two EBV-transforming proteins that are presumed to be of importance
in EBV-induced lymphomagenesis (6, 7, 8). The responsibility of the
immunodeficiency is clearly evidenced by the known epidemiological
association between very low CD4+ T lymphocyte counts and
the high risk of development of PCNSL (9); the propensity of these
lymphomas to grow in the brain could also be related to an even more
depressed immune surveillance in this site. Thus, both EBV and profound
immunodeficiency could act in the development of PCNSL, as is the case
in lymphomas following drug-induced immunosuppression in transplant
patients (10, 11). The role of chronic antigenic stimulation as a
possible step in lymphomagenesis (12) with regard to HIV-associated
lymphoma is suggested by different indirect arguments: 1) HIV-infected
patients have B cell chronic activation that could predispose them to B
cell malignancy; 2) such patients often have paraproteinemias that can
display anti-HIV activity (13); 3) the anti-HIV and
anti-IgG specificities were demonstrated in two IgMs produced by
AIDS-associated lymphoma cell lines (14); and 4) it was recently shown
that systemic AIDS-associated B cell lymphomas preferentially use
IgVH4 genes (15). These different arguments are
relevant in the case of systemic forms of AIDS-associated lymphomas. In
trying to understand the main forces driving the lymphoma process
during PCNSL, we must take into consideration the molecular analysis of
the V region genes of lymphomatous Ig, which could indicate one of
these hypotheses indirectly; if a peculiar Ag is responsible for
chronic B cell stimulation and the subsequent transformation, then the
VH repertoire could be biased, like in AIDS-associated
systemic lymphomas, but if EBV as well as profound local
immunosuppression is primarily responsible, then the VH
repertoire should be more diverse. This study was performed to directly
address these questions in five random cases of AIDS-associated PCNSL.
 |
Materials and Methods
|
|---|
Patients
Characteristics of the patients are described in Table I
. All of these lymphomas were defined as
immunoblastic lymphomas with plasmacytic differentiation. The five
cases were obtained from an autopsy cohort studied at
Pitié-Salpêtrière Hospital (Prof. J. J.
Hauw, Neuropathology Laboratory, Paris, France).
Clinical information, including age, sex, CD4 cell count, and
HIV-associated disorders, was collected for each patient. The autopsy
material was classically processed with paraffin-embedding and
hematoxylin-eosin and Giemsa stainings. The five cases were classified
as immunoblastic lymphomas with plasmacytic features. For each case, a
sample was snap-frozen in liquid nitrogen until it was used for
molecular analysis. DNA was prepared as described previously (16) using
SDS lysis, proteinase K digestion, phenol-chloroform extraction, and
ethanol precipitation.
Polymerase chain reaction
Two sets of nested amplifications of the purified DNA were
performed in a GeneAmp PCR system (Perkin-Elmer, Foster City,
CA). For the first set of six PCRs, we used an external
antisense JH consensus primer and one of each of the six
VH family-specific leader primers; the VH1
primer was used to detect the VH7 subfamily (see Table II
). Primers were used at a 1-µM
concentration. A total of 1 U of Taq polymerase
(Perkin-Elmer), Taq buffer, and 100 µM of deoxynucleoside
triphosphates were added to a final volume of 100 µl. After 2
min of denaturation at 94°C, samples were amplified for 30 cycles;
each cycle consisted of 1 min at 94°C, 1 min 15 s at a
temperature depending upon the primer sequence (optimized during
previous experiments; Table II
), and 1 min at 72°C followed by
elongation for 10 min at 72°C. A total of 5 µl of each of the first
set of PCR reactions was used to perform a second set of PCR reactions
by adding an internal JH consensus primer and one of six
internal VH family-specific leaders. These primers were
designed with restriction sites for subsequent cloning. The
amplification products were analyzed on ethidium bromide-stained 1%
agarose gels for 45 min at 110 V.
Cloning and DNA sequencing
The PCR products were ethanol-precipitated, digested by
SalI and Bsp106, and ethanol precipitated again before
ligation into pBluescript (Stratagene, La Jolla, CA) using T4 DNA
ligase overnight at 4°C. dsDNA sequencing was performed using
the Thermo Sequenase cycle-sequencing kit (Amersham,
Buckinghamshire, U.K.) according to the manufacturers
recommendations.
Somatic mutation analysis
For n, the number of random mutations, the number of
replacement (R) mutations should equal 0.75 x n, and the
number of expected silent (s) mutations should be equal to 0.25 x
n. Without selection, the R and S mutations should
distribute randomly throughout the various VH regions
according to their respective sizes. A binomial mutation model
developed by Schlomchick et al. was used to calculate the probability
(p) that kR mutations would occur in the
complementarity-determining regions (CDRs) given the number of total
mutations. Assuming that Ig function is maintained, the number of R
mutations in the frameworks (FRs) was doubled in the formula to obtain
a more accurate p value (17).
 |
Results
|
|---|
Analysis of Ig VH gene subgroups
PCR-amplified genomic DNA was analyzed in ethidium bromide agarose
gels. The results are shown in Fig. 1
. In
four cases, only one
520-bp PCR product was generated using
oligonucleotides specific for JH and the leader sequence of
each Ig VH family; two lymphoma samples used
VH4 genes (COL, CORT), one used a VH5 gene
(BOU), and one used a VH1 gene (CEL). Alternatively, PCR
with DNA of NIC generated two
520-bp PCR products (VH1
and VH6). Taken together, the results indicate a
heterogeneous use of Ig VH genes by lymphomatous cells
originating from different patients.

View larger version (38K):
[in this window]
[in a new window]
|
FIGURE 1. PCR amplification of rearranged VHDJH genes.
PCR products are shown following electrophoresis in ethidium
bromide-stained 1% agarose gels. The products were generated by nested
PCR amplification of DNA prepared from tumor specimens with each one of
the six 5' VH family-specific leader region primers,
VH1VH6 (lanes 16,
respectively), and with the 3' JH primers. For each of the
six VH primers, a negative control without DNA was included
(lanes T1T6). The arrow ( ) indicates the position
of the wells.
|
|
Molecular analysis of the lymphoma-rearranged VH
region genes
The PCR products of the V regions were cloned into pBluescript,
and multiple clones were randomly sequenced. The nucleic acid sequences
of each PCR product are given in Fig. 2
, AF, and
Fig. 4
. CDR3 analysis confirms the monoclonality of the PCNSL cells in
four of five patients as well as the oligoclonality in the fifth
patient (NIC). All of the sequences obtained represent a functional VDJ
rearrangement.

View larger version (28K):
[in this window]
[in a new window]
|
FIGURE 4. Heavy chain CDR3 regions. Lines 1 and 2 display the amino acid and
nucleotide sequences of the CDR3 of each Ig of AIDS PCNSL.
Lines 3, 4, and 5 are the germline JH and D segments that
have the highest homology to that of the lymphoma-derived Ig
VH region gene. Periods (.) indicate sequence homology.
CDR3 is defined as described by Sanz (23).
|
|
Comparison of the sequences with the most homologous germline
VH genes may give an indication regarding a putative
Ag-driven process that occurred before the oncogenic transformation.
The homology search was performed with the International Immunogenetics
(IMGT) database (18), and the results are presented in Table III
. Some of the VH are very
close to the putative germline (NIC VH1, 99.3% homology
with DP15); others differ further from the candidate germline: COL
VH4 has 93% homology with an allelic variant of DP63
(VH4-34*03), and CEL VH1 has 93.9% homology with an
allelic variant of DP10 (VH1-69*01). Because most human VH
genes and their allelic variants have now been identified and included
in the IMGT database (19), it is highly probable that these differences
represent somatic mutations. Because the introns located between the
leader and the VH regions are not as highly conserved as
the coding regions and can be used to identify the germlines (20), we
have sequenced the introns of the CEL and COL VH rearranged
genes to verify this possibility (Fig. 3
). The homology search performed
with these sequences and two different databases (IMGT and GenBank)
confirmed the initial identification of the putative germline: only one
(COL) and two (CEL) changes were observed in these noncoding regions,
which were also subjected to the mutation machinery. To interpret the
significance of these V region mutations, we applied the binomial
model-derived probabilities (see Materials and Methods) to
show that the distribution of the mutations was not random in the case
of patients CEL and COL, clearly suggesting an Ag-driven selection
(Table III
). This result was confirmed using a modification of the
calculation introduced by Chang and Casali (21). For the other
patients, the number of mutations was too low for us to come to a
conclusion.

View larger version (15K):
[in this window]
[in a new window]
|
FIGURE 3. Patients CEL and COL Ig VH-intron sequences. Nucleotide
sequences of the intronic regions located between the leader and the
VH as well as comparison with the closest introns. CEL is
aligned with the 5' intronic sequence of the allelic variant VH1-69*01;
COL is aligned with the 5' intronic sequence of the allelic variant
VH4-34*03.
|
|
The patient NIC merits further discussion: two types of
VHDJH rearrangements were detected
(VH1 and VH6). Because all of the
VH1 sequences were identical, they most likely correspond
with the heavy chain rearrangement expressed by lymphomatous B cells.
In contrast, the four VH6 analyzed sequences were derived
from three different B cell clones in view of CDR3. We could consider
that these VH6-expressing B cell clones are innocent
bystander B lymphocytes present in the biopsy specimen. However, if
this hypothesis is correct, it is surprising to find only
VH6-expressing B cells in contact with the tumor cells,
because the VH6 gene is unique in humans, rarely used in
adult B cells, and rarely mutated (22).
CDR3 is composed of 1129 amino acid residues (Fig. 4
). Assignment of the D gene segment
usage was performed using the criteria proposed by Sanz (23). COL and
CORT CDR3 probably arose through D-D fusion; the D gene used by CEL
could not be identified. Comparison of CDR3 and FR4 (data not shown)
with known JH segments indicated that BOU and CEL probably
use JH5, that COL uses JH4, and that CORT and
NIC VH1 use JH6.
To evaluate intraclonal variability, we compared randomly selected
sequences (shown in Fig. 2
, AF); there was no difference
observed between the sequences of the patients CORT and CEL, one
nucleotide change in one of the four sequences in patients BOU and COL,
and one or two changes in patient NIC VH1. The very low
frequency of these base changes is compatible with the known error rate
of the enzyme Taq polymerase.
 |
Discussion
|
|---|
We report the first molecular analysis of the VH genes
expressed by AIDS-associated PCNSL. This analysis confirms the
monoclonality of the B cell proliferation without ambiguity in four of
five patients. The results concerning the fifth patient (NIC) are more
difficult to interpret. Two different VH families
(VH1 and VH6) were amplified from biopsy
material. The sequences originating from the VH1 material
were identical and are thought to represent the product of the
monoclonal B cell lymphoma. On the contrary, the VH6
rearrangements were in general distinct from each other and were
consequently expressed by different B cells. As stated above, the
presence of these cells in contact with the tumor cells is intriguing:
1) If these cells are bystander B cells, other VH families
that are more frequently expressed in adult B cells should have been
detected; 2) if they are not bystander B cells, the possibility that
their presence is related to a specific Ag should be considered, which
in turn could be assigned to the VH6 product (superantigen
effect?).
It was recently reported that AIDS-associated systemic B cell lymphomas
(10 cases) expressed a restricted set of VH genes that
primarily belong to the VH4 family (15). Our data on
AIDS-associated PCNSL give us a more diverse representation of the
VH families, without significant bias toward a peculiar
VH family. However, we were quite surprised to find that we
did not detect any VH3-containing rearrangement expressed
by the lymphoma cells despite the fact that the VH3 genes
encode most of the Ig expressed by normal adult B cells (21) and that
the VH3 gene products could have a distinctive ability to
bind to HIV glycoprotein 120 (24). It is still unclear whether
this binding capacity of the VH3 gene products is
responsible for a selective depletion of VH3-expressing B
cells in HIV-infected patients (25, 26, 27), but this mechanism could
account for the apparently low representation of the VH3
genes during AIDS systemic B cell lymphomas (15) as well as during
PCNSL. However, published cases reporting on the occurrence of
VH3 expressing AIDS-associated Burkitts lymphomas should
also be mentioned (28, 29). The mutation analysis of our cases was
possible, even though we did not isolate the respective germline genes
from these patients. Indeed, it is believed that most human
VH genes have now been identified, and that individual
polymorphism is generally low (19). In two of the five patients, we
found a statistically significant preference for R mutations in the
VH CDRs compared with the FRs (binomial model). The
accumulation of such mutations in normal B cells generally indicates
that the cell of origin migrated through a germinal center, where it
was subjected to antigenic contact and where the hypermutation
mechanism operated (30, 31). This is also an indirect argument
suggesting that the Ag plays a role in the selective process operating
in a B cell population. The low degree of mutations in the
VH of the remaining three patients prevents any statistical
analysis but does not exclude the possibility that the B cell of origin
was also driven by antigenic exposure. The analysis of CDR3 provides
additional evidence for a possible selection. All CDR3 have
nonconservative base differences from the deduced D and JH
segments. Moreover, there is a preferential use of long CDR3 (mean
= 19 vs 13 for the CDR3 used by unselected normal adult B cells) and of
D-D fusions (only 10% of Ig heavy chain CDR3 expressed by normal adult
B cells seems to arise by D-D fusion). It is noteworthy that both of
these features were repeated by Kipps (15) in AIDS-associated systemic
B cell lymphoma. The almost complete absence of ongoing
mutations in the lymphoma cells could suggest that PCNSL does not
derive directly from germinal center B cells. However, Larocca et al.
recently described mutations in the 5' region of the bcl-6 gene in some
AIDS-associated PCNSL cells; these mutations are considered to be an
argument for either the germinal center or the postgerminal center B
cell origin (32). Further work will be necessary to elucidate this
point. Thus, the cell of origin more likely matured in the periphery,
at least in the patients CEL and COL, and then migrated to the brain.
Because these patients do not present any evidence of lymphoma in the
periphery, it is reasonable to speculate that the last transforming
event(s) took place in the CNS. The responsibility of the depressed
immune surveillance in this site is frequently suggested, but the
HIV-infected tissue microenvironment could also play a direct role in
the initiation of lymphomagenesis.
In the case of AIDS-associated PCNSL, what could be the antigenic
contact? The answer to this question is still open to
interpretation, because numerous pathogens can be found both in
the brain and in the periphery of patients with AIDS including HIV,
CMV, EBV, and Toxoplasma gondii. The findings of Ng et al.
(14) show that two IgMs produced by AIDS lymphoma cell lines are able
to react with HIV glycoprotein 160 or human IgG, suggesting a
role for chronic antigenic stimulation during the process of
lymphomagenesis. This type of mechanism is best exemplified in
mucosa-associated lymphoid tissue gastric lymphoma, in which the growth
of the transformed B cells is dependent upon the presence of
Helicobacter pylori (33, 34, 35). Whether this hypothesis is of
importance during AIDS-associated PCNSL is unclear and merits further
evaluation: even though the expressed VH genes are diverse,
the mutation analysis in two of the five cases and the known importance
of both the stochastically derived heavy chain CDR3 (36, 37) and
the somatic mutations in determining Ab specificity encourage further
studies to address this issue.
 |
Footnotes
|
|---|
1 This research was supported by grants from the Fondation pour la Recherche Médicale (Sidaction) and the Association Nationale de la Recherche sur le Syndrome dImmuno-Déficience Acquise. 
2 Address correspondence and reprint requests to Dr. Jean-Louis Pasquali, Laboratoire dImmunopathologie, Institut dImmunohématologie, Hôpital Civil, 1 Place de lHôpital, 67091 Strasbourg, France. E-mail address: 
3 Abbreviations used in this paper: CNS, central nervous system; PCNSL, primary CNS lymphoma; R, replacement; S, silent; CDR, complementarity-determining region; FR, framework. 
Received for publication April 7, 1998.
Accepted for publication October 26, 1998.
 |
References
|
|---|
-
Fine, H. A., R. J. Mayer. 1993. Primary central nervous system lymphoma. Ann. Intern. Med. 119:1093.[Abstract/Free Full Text]
-
Raphael, M., O. Gentilhomme, M. Tulliez, P.-A. Byron, J. Diebold.. 1991. Histopathologic features of high-grade non-Hodgkins lymphomas in acquired immunodeficiency syndrome: The French Study Group of Pathology for Human Immunodeficiency Virus-Associated Tumors. Arch. Pathol. Lab. Med. 115:15.[Medline]
-
Knowles, D. M., and A. Chadburn. 1992.
Neoplastic Hematopathology. D. M. Knowles,
ed. Williams and Wilkins, Baltimore, p.773.
-
Gaidano, G., R. Dalla-Favera. 1995. Molecular pathogenesis of AIDS-related lymphomas. Adv. Cancer. Res. 67:113.[Medline]
-
Bashir, R. M., N. L. Haris, F. H. Hochberg, R. M. Singer. 1989. Detection of Epstein-Barr virus in CNS lymphomas by in-situ hybridation. Neurology 39:813.[Abstract/Free Full Text]
-
Pallesen, G., S. J. Hamilton-Dutoit, M. Rowe, L. S. Young. 1991. Expression of Epstein-Barr virus latent gene products in tumour cells of Hodgkins disease. Lancet 337:320.[Medline]
-
Hamilton-Dutoit, S. J., M. Raphael, J. Audouin, J. Diebold, I. Lisse, C. Pedersen, E. Oksenhendler, L. Marelle, G. Pallesen. 1993. In situ demonstration of Epstein-Barr virus small RNAs (EBER1) in acquired immunodeficiency syndrome-related lymphomas: correlation with tumor morphology and primary site. Blood 82:619.[Abstract/Free Full Text]
-
Camilleri-Broet, S., F. Davi, J. Feuillard. 1996. High expression of latent membrane protein 1 of Epstein-Barr virus BCL-2 oncoprotein in acquired immunodeficiency syndrome-related primary brain lymphomas. Blood 87:706.[Abstract/Free Full Text]
-
Levine, A. M., J. Sullivan-Halley, M. C. Pike, M. U. Rarick, C. Loureiro, M. Bernstein-Singer, E. Willson, R. Brynes, J. Parker, S. Rasheed, P. S. Gill. 1991. Human immunodeficiency virus-related lymphoma: prognostic factors predictive of survival. Cancer 68:2466.[Medline]
-
Penn, I.. 1977. Development of cancer as a complication of clinical transplantation. Transplant. Proc. 9:1121.[Medline]
-
Weintraub, J., R. A. Warnke. 1982. Lymphoma in cardiac allotransplant recipients: clinical and histological features and immunological phenotype. Transplantation 33:347.[Medline]
-
Monroe, J. G., L. E. Silberstein. 1995. HIV-mediated B-lymphocyte activation and lymphomagenesis. J. Clin. Immunol. 15:61.[Medline]
-
Ng, V. L., K. H. Chen, K. M. Hwang, H. Khayam-Bashi, M. S. McGrath. 1989. The clinical significance of human immunodeficiency virus type 1-associated paraproteins. Blood 74:2471.[Abstract/Free Full Text]
-
Ng, V. L., M. H. Hurt, C. H. Fein, F. Khayam-Bashi, J. Marsh, W. M. Nunes, L. W. McPhaul, E. Feigal, P. Nelson, B. G. Herndier, et al 1994. IgMs produced by two acquired immune deficiency syndrome lymphoma cell lines: Ig binding specificity and VH-gene putative somatic mutation analysis. Blood 83:1067.[Abstract/Free Full Text]
-
Bessudo, A., V. Cherepakhin, T. A. Johnson, L. Z. Rassenti, E. Feigal, T. J. Kipps. 1996. Favored use of immunoglobulin VH4 genes in AIDS-associated B-cell lymphoma. Blood 88:252.[Abstract/Free Full Text]
-
Camilleri-Broet, S., F. Davi, J. Feuillard, D. Seilhean, J. F. Michiels, P. Brousset, B. Epardeau, E. Navratil, K. Mokhtari, C. Bourgeois, et al 1997. AIDS-related primary brain lymphomas: histopathologic and immunohistochemical study of 51 cases. The French Study Group for HIV-Associated Tumors. Hum. Pathol. 28:367.[Medline]
-
Schlomchick, M. J., A. H. Aucouin, D. S. Pisetsky, M. J. Weigert. 1987. Structure and function of anti-ADN autoantibodies derived from a single autoimmune mouse. Proc. Natl. Acad. Sci. USA 84:9150.[Abstract/Free Full Text]
-
Giudicelli, Y., J. Bochmer, W. Muller, C. Busin, S. Marsh, R. Bontrop, L. Marc, A. Malik, M. P. Lefranc. 1997. IMGT, the international ImMunoGeneTics database. Nucleic Acids Res. 25:206.[Abstract/Free Full Text]
-
Cook, G. P., I. M. Tomlinson. 1995. The human immunoglobulin VH repertoire. Immunol. Today 16:237.[Medline]
-
Soto-Gil, R. W., T. Olee, B. K. Klink, T. P. Kenny, D. L. Robbins, D. A. Carson, P. P. Chen. 1992. A systematic approach to defining the germline gene counterparts of a mutated autoantibody from a patient with rheumatoid arthritis. Arthritis Rheum. 35:356.[Medline]
-
Chang, B., P. Casali. 1994. The CDR1 sequences of a major proportion of human germline Ig VH genes are inherently susceptible to amino acid replacement. Immunol. Today 15:367.[Medline]
-
Suzuki, I., L. Pfister, A. Glas, C. Nottenburg, E. C. Milner. 1995. Representation of rearranged VH gene segments in the human adult antibody repertoire. J. Immunol. 154:3902.[Abstract]
-
Sanz, I.. 1991. Multiple mechanisms participate in the generation of diversity of human H chain CDR3 regions. J. Immunol. 147:1720.[Abstract]
-
Berberian, L., L. Goodglick, T. J. Kipps, J. Braun. 1993. Immunoglobulin VH3 gene products: natural ligands for HIV gp120. Science 261:1588.[Abstract/Free Full Text]
-
Berberian, L., Y. Valles-Ayoub, N. Sun, O. Martinez-Maza, J. Braun. 1991. A VH clonal deficit in human immunodeficiency virus-positive individuals reflects a B-cell maturational arrest. [Published erratum appears in 1991 Blood 78:1899.]. Blood 78:175.[Abstract/Free Full Text]
-
David, D., C. Demaison, L. Bani, M. Zouali, J. Theze. 1995. Selective variations in vivo of VH3 and VH1 gene family expression in peripheral B cell IgM, IgD, and IgG during HIV infection. Eur. J. Immunol. 25:1524.[Medline]
-
Bessudo, A., L. Rassenti, E. Feigal, T. J. Kipps. 1995. Immunoglobulin VH gene repertoire of patients with AIDS. Blood 86:929a.
-
Amatiglio, N., A. Vonsover, I. Hakim, Y. Neumann, Z. Mark, F. Brok-Simoni, I. Ben-Bassat, G. Rechavi. 1994. Immunoglobulin VH3-positive AIDS-related Burkitts lymphoma: a possible role for the HIV gp120 superantigen. Acta Haematologica 91:103.[Medline]
-
Eclache, V., C. Magnac, O. Pritsch, H. J. Decluse, F. Davi, M. Raphael, G. Dighiero. 1996. Complete nucleotide sequence of Ig V genes in three cases of Burkitts lymphoma associated with AIDS. Leuk. Lymphoma 20:281.[Medline]
-
Kuppers, R., M. Zhao, M.-L. Hansmann, K. Rajewsky. 1993. Tracing B cell development in human germinal centres by molecular analysis of single cells picked from histologic sections. EMBO J. 12:4955.[Medline]
-
Berek, C., A. Berger, M. Appel. 1991. Maturation of the immune response in germinal centers. Cell 67:1121.[Medline]
-
Larocca, L. M., D. Capello, A. Rinelli, S. Nori, A. Antinori, A. Gloghini, A. Cingolani, A. Migliazza, G. Saglio, M. Raphael, A. Carbone, G. Gaidano. 1997. The molecular and phenotypic profile of AIDS-related and AIDS-unrelated primary central nervous system lymphoma is consistent with histogenetic derivation from germinal center-related B-cells. Blood 90:337.
-
Parsonnet, J., S. Hansen, L. Rodriguez, A. B. Gelb, R. A. Warnke, E. Jellum, N. Orentreich, J. H. Vogelman, G. D. Friedman. 1994. Helicobacter pylori infection and gastric lymphoma. N. Engl. J. Med. 330:1267.[Abstract/Free Full Text]
-
Wotherspoon, A. C., C. Doglioni, T. C. Diss, L. Pan, A. Moschini, M. deBoni, P. G. Isaacson. 1993. Regression of primary low-grade B-cell gastric lymphoma of mucosa-associated lymphoid tissue type after eradication of Helicobacter pylori. Lancet 342:575.[Medline]
-
Bayerdorffer, E., A. Neubauer, B. Rudolph, C. Thiede, N. Lehn, S. Eidt, M. Stolte. 1995. Regression of primary gastric lymphoma of mucosa-associated lymphoid tissue type after cure of Helicobacter pylori infection. Lancet 345:1591.[Medline]
-
Martin, T., R. Crouzier, J.-C. Weber, T. Kipps, J.-L. Pasquali. 1994. Structure-function studies on a polyreactive (natural) autoantibody: polyreactivity is dependent on somatically generated sequences in the third complementarity-determining region of the antibody heavy chain. J. Immunol. 152:5988.[Abstract]
-
Crouzier, R., T. Martin, J.-L. Pasquali. 1995. VH region, VL region, and heavy chain CDR3 influences on the mono- and polyreactivity and on the affinity of human monoclonal rheumatoid factors. J. Immunol. 154:4526.[Abstract]
This article has been cited by other articles:

|
 |

|
 |
 
J. M. Baehring, D. Damek, E. C. Martin, R. A. Betensky, and F. H. Hochberg
Neurolymphomatosis
Neuro-oncol,
April 1, 2003;
5(2):
104 - 115.
[Abstract]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Montesinos-Rongen, R. Kuppers, D. Schluter, T. Spieker, D. Van Roost, C. Schaller, G. Reifenberger, O. D. Wiestler, and M. Deckert-Schluter
Primary Central Nervous System Lymphomas Are Derived from Germinal-Center B Cells and Show a Preferential Usage of the V4-34 Gene Segment
Am. J. Pathol.,
December 1, 1999;
155(6):
2077 - 2086.
[Abstract]
[Full Text]
[PDF]
|
 |
|