SEARCH · Search PubMed

Results for “Marginal zone B cells”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17Linked to original sources

PubMedDate not supplied

Extranodal marginal zone B-cell lymphoma of malt type involving the cavernous sinus.

Mucosa-associated lymphoid tissue (MALT) lymphomas are low-grade B-cell neoplasms that occur in a variety of extranodal sites. Only rarely has this entity been discovered as a primary tumor involving the dura of the cavernous sinus. We report the case of a 46 year old woman who presented with a mass involving the cavernous sinus that was originally diagnosed as a meningioma by MRI. However, at surgery the mass was found to be an extranodal marginal zone B-cell lymphoma of the MALT type. The patient underwent partial excision of the lesion followed by radiation. There are only seven other cases of marginal zone B-cell lymphoma involving the intracranial dura reported in the literature. These patients were females who presented with intracranial lesions thought to be consistent with meningioma by preoperative radiographic imaging. MALT lymphomas of the dura, as their counterparts in other organs, appear to have favorable clinical outcomes and excellent long-term prognoses with local therapy alone.

Brain Neoplasms↗

PubMed1995

Primary gastric lymphomas (MALTomas): a nuclear image analysis comparison with lymph node monocytoid B-cells and marginal zones of spleen and Peyer's patches.

Centrocyte-like cells of marginal zones of follicles of gastrointestinal lymphoid tissue, which have their analogous in marginal zone of splenic white pulp and in lymph node monocytoid B-lymphocytes, are thought to be the normal counterpart of lymphomas of MALT (MALTomas). However, the cell population of MALTomas is often polymorphic and also contains cells morphologically different from centrocytes. Since conventional morphologic analysis may not be accurate enough and the phenotype may change in different stages of B-cell lineage, the marginal zone of Peyer's patches (PMZ) and splenic white pulp (SMZ), the lymph node monocytoid B-lymphocytes (ML), 3 nodal monocytoid B-cell lymphomas (L) and 16 gastric MALTomas (M) were studied by means of automated nuclear image analysis for area, irregularity, and chromatin texture assessment. Immunophenotyping on paraffin sections and polymerase chain reaction (PCR) for detecting monoclonality and t(14-18) chromosome breakpoints at DNA levels, on paraffin section extractions, were also done. In 14 MALTomas, clonal Ig heavy chain rearrangement was detected and in none of these were found t(14-18) chromosome breakpoints. The nuclei of the control group (PMZ, SMZ and ML) showed the same morphologic characteristics, ie. size, irregularity, chromatin texture. MALTomas and nodal lymphomas were distributed into 3 clusters: (1) with larger nuclei, light chromatin (euchromatin-richer) (5 MALTomas, 2 nodal lymphomas together with the control group); (2) nuclei with the same area size, but darker (eterochromatin-richer) (6 MALTomas and 1 nodal lymphoma); (3) with smaller and darker nuclei (5 MALTomas). Chromatin textural differences were maintained in the same nuclear size class in the 3 clusters. Only a few MALTomas had nuclear features not significantly different from controls, inter-case and intra-case variability being evident.

B-Lymphocytes↗

PubMed1997

Primary cutaneous marginal zone B-cell lymphoma: a recently described entity of low-grade malignant cutaneous B-cell lymphoma.

Recently a new classification of primary cutaneous B-cell lymphomas (PCBCLs) has been proposed by the European Organization for Research and Treatment of Cancer (EORTC)--Cutaneous Lymphoma Project Group. The marginal zone B-cell lymphomas (MZLs) were not included as a distinct entity because of insufficient experience and controversial opinions. We have studied 32 patients (M:F ratio 1.5:1; age range 25-93 years; mean age 49.6 years; median age 50 years) to determine the diagnostic criteria of primary cutaneous MZL and the relationship with other low-grade malignant PCBCLs. For comparison, three patients with immunocytoma were included in the study. Clinically, patients presented with solitary or clustered reddish or red-brown papules, nodules, and plaques, sometimes surrounded by an erythematous halo. Histopathologic sections showed nodular or diffuse infiltrates involving the dermis and subcutaneous fat. Cytomorphologically small to medium-sized cells with indented nuclei and abundant pale cytoplasm (marginal zone cells, centrocyte-like cells) predominated. In addition, scattered blasts, lymphoplasmacytoid cells, and plasma cells were observed below the epidermis and at the periphery of the infiltrates. Reactive germinal centers were present in 75% of the cases. The three cases of immunocytoma showed a more monomorphous pattern with predominance of lymphoplasmacytoid cells. The marginal zone cells showed a CD20+, CD79a+, CD5- and Bcl-2+ immunophenotype. They expressed immunoglobulin G in the majority of the cases. Staining with the monocytoid B cell-related antibody KiM1p gave positive results in all specimens with a typical intracytoplasmic granular pattern. A monoclonal distribution of immunoglobulin light chains was observed in marginal zone cells in 75% of the cases. Germinal centers, when present, were either polyclonal or negative for both kappa and lambda light chains. Monoclonal rearrangement of the JH gene was detected via polymerase chain reaction (PCR) in 18 of 26 investigated specimens. Analysis in 12 patients of the bcl-2/immunoglobulin heavy chain gene rearrangement using PCR yielded negative results. Lesions were treated by surgical excision followed in some patients by local radiotherapy. Systemic antibiotic therapy was administered to three patients, with good response in two. The prognosis is excellent. After a mean follow-up of 47.9 months (range 6-252; median 24) all patients are alive without signs of systemic lymphoma. Primary cutaneous MZL represents a distinct clinicopathologic subtype of low-grade malignant PCBCL.

Adult↗

PubMed2005

The CD45 isoform B220 identifies select subsets of human B cells and B-cell lymphoproliferative disorders.

The B220 isoform of CD45, a pan B-cell marker in mice, is expressed by only a subset of human B cells that do not express the memory B-cell marker CD27, suggesting that it is a differentiation-specific isoform of CD45. We examined normal human peripheral blood B cells, secondary lymphoid tissue, and a range of human B-cell lymphoproliferative disorders for the expression of B220 by flow cytometric immunophenotyping and immunohistochemical staining. We found that a subset of human B cells in peripheral blood is positive for B220 by flow cytometric immunophenotypic analysis. In reactive lymphoid tissues, B220 is expressed by B cells occupying the mantle zones and by a subpopulation of germinal center cells, but, in contrast, marginal zone B cells in the spleen do not express B220. Of 94 cases of B-cell lymphoproliferative disorders, 33 (35%) were positive for B220 by flow cytometric immunophenotypic analysis, including most cases of marginal zone lymphoma, follicular lymphoma, and lymphoplasmacytic lymphoma. In contrast, all cases of precursor B lymphoblastic leukemia/lymphoma, mantle cell lymphoma, and chronic lymphocytic leukemia/small lymphocytic lymphoma were negative for B220. Immunohistochemical staining for B220 correlated with flow cytometric analysis for all cases studied by both methods. Our data demonstrate that B220 is expressed in a select subset of normal, reactive B cells in a pattern that is consistent with a marker of naive B cells. However, this restricted expression pattern is not seen in B-cell lymphoproliferative disorders. Discordance between the B220 expression patterns of normal mantle and marginal zone B cells and their respective neoplastic counterparts may aid in the distinction between normal and neoplastic proliferations at these anatomical sites.

B-Lymphocytes↗

PubMed2004

Diagnosis of a primary uveal extranodal marginal zone B-cell lymphoma by chorioretinal biopsy: case report.

PURPOSE: To report the clinical, histopathological and molecular biological findings of a primary extranodal marginal zone B-cell lymphoma (EMZL) of the uvea. METHODS: Conventional histology, immunohistochemistry and polymerase chain reaction for immunoglobulin heavy chain gene rearrangement (IgH-PCR) and GeneScan analysis were performed on a chorioretinal biopsy. RESULTS: Histological examination of the chorioretinal biopsy demonstrated a dense infiltrate of small centrocyte-like cells, plasmacytoid tumour cells and occasional blasts. The tumour cells were positive for CD20, showed monotypical expression for Ig-kappa and IgM, and a growth fraction of 10%. Clonality analysis using IgH-PCR disclosed a monoclonal B-cell population. Following localised irradiation of 35 Gy, a complete remission was achieved. CONCLUSION: This report describes a rare uveal EMZL diagnosed following investigation of a chorioretinal biopsy. Despite its rarity, ophthalmic pathologists should consider the diagnosis of a primary uveal EMZL when reviewing chorioretinal biopsies.

Biopsy, Needle↗

PubMed2006

Prevalence of HCV infection in nongastric marginal zone B-cell lymphoma of MALT.

BACKGROUND: Hepatitis C virus (HCV) infection is frequently associated with B-cell non-Hodgkin's lymphomas. We investigated the prevalence of HCV infection in nongastric marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT) in order to define the relationship between the viral infection and the presenting features, treatment, and outcome. METHODS: We retrospectively studied 172 patients with a histological diagnosis of marginal zone B-cell lymphoma of MALT, except for stomach, and with available HCV serology, among a series of 208 patients. RESULTS: HCV infection was documented in 60 patients (35%). Most HCV-positive patients (97%) showed a single MALT organ involvement. HCV-positive patients showed a more frequent involvement of skin (35%), salivary glands (25%), and orbit (15%). The majority of stage IV HCV-positive patients (71%) had a single MALT site with bone marrow involvement. The overall response rate was similar in HCV-positive (93%) and HCV-negative patients (87%). Overall survival (OS) and event-free survival (EFS) did not differ according to HCV infection. In multivariate analysis, advanced disease (stage III-IV) was associated with a poorer OS (P = 0.0001), irrespective of HCV serostatus. CONCLUSIONS: This study shows that nongastric marginal zone lymphomas are characterized by a high prevalence of HCV infection. Patients with involvement of a single MALT site have the highest prevalence of HCV. HCV-positive nongastric lymphomas of MALT show an indolent course similar to HCV-negative patients and seem an ideal target for exploiting the antilymphoma activity of antiviral treatments.

Antibodies, Viral↗

PubMed2005

Complement dependency of splenic localization of pneumococcal polysaccharide and conjugate vaccines.

The immune response to polysaccharides is initiated when polysaccharides bind complement factor C3d, and these polysaccharide-C3d complexes subsequently localize on splenic marginal zone B cells strongly expressing CD21 (complement receptor 2). Infants and children under the age of 2 years have low or absent expression of CD21 on their marginal zone B cells, and consequently do not adequately respond to polysaccharides. In contrast, polysaccharide-protein conjugate vaccines are able to induce antibodies at this young age. Conjugate vaccines apparently overcome the necessity for CD21-C3d interaction for an antipolysaccharide immune response. We demonstrate in a rat model that localization of pneumococcal polysaccharides on splenic marginal zone B cells indeed is complement dependent. We also show that pneumococcal conjugates do not specifically localize on splenic marginal zone B cells and that splenic localization of polysaccharide conjugates is independent of the presence of complement. Thus, the induction of antipolysaccharide antibodies by conjugate vaccines apparently can occur independently of CD21-C3d interaction. These basic findings may explain the effectiveness of conjugated vaccines in young children and may open the way for their application in other patient groups.

Animals↗

PubMed1999

Immunoglobulin VH gene expression among extranodal marginal zone B-cell lymphomas of the ocular adnexa.

PURPOSE: Most lymphomas of the ocular adnexa are primary extranodal non-Hodgkin's lymphomas of the B-cell type, with the most common lymphoma subtype being the extranodal marginal-zone B-cell lymphoma (EMZL). Analysis of somatic mutations in the variable (V) region of the Ig heavy (H)-chain gene segment suggests that EMZL development in other locations is dependent on antigen stimulation. The purpose of this study was to analyze the presence of somatic hypermutations in clonally rearranged Ig H-chain V genes of this lymphoma entity in the ocular adnexa and to estimate whether the mutation pattern is compatible with antigen selection. METHODS: Twenty-six cases of EMZL of the ocular adnexa were diagnosed on the basis of morphology, histology, and immunohistology. A nested polymerase chain reaction (PCR) was performed on DNA extracted from paraffin sections. The isolated PCR products were sequenced and compared with published VH germline segments to determine the number of somatic mutations in the complementarity-determining region (CDR) 2 and framework (FW) region 3. RESULTS: The number of somatic mutations in the cases of EMZL varied between 0 and 24: Five cases involved 0 to 3 somatic mutations, and the remaining 21 cases involved 4 to 24 mutations. Based on the ratio of replacement (R) to silent (S) mutations in the CDR2 or FW3 regions, antigen selection seems to have occurred in 60% of ocular adnexal EMZL. The VH3 family was the most commonly expressed germline VH family (54%), followed by VH4 (23%), with biased usage of the latter. Some germline VH1 genes used included DP-8, DP-10, DP-53, DP-63 (VH4.21), and DP-49, which are frequently used by autoantibodies (e.g., rheumatoid factors) and natural autoantibodies. CONCLUSIONS: EMZLs of the ocular adnexa have an Ig H-chain mutation pattern that supports the concept that they represent a clonal expansion of post-germinal-center memory B-cells in most instances. In two thirds of cases, antigen selection may have occurred, and autoantibodies may have a role in their development.

Adolescent↗

PubMed2000

T-Independent immune response: new aspects of B cell biology.

Recent results emphasize the roles of T-independent antibody response in humoral defenses, for which B1 cells and marginal zone B cells are mostly responsible. We discuss how these cells are activated, migrate, and differentiate into antibody-producing cells in various lymphoid tissues. Based on recent findings in each of these areas of B cell biology, we propose a possible mechanism for peripheral tolerance of autoreactive B cells at target organs.

Animals↗

PubMed2000

Analysis of the P53, RB/D13S25, and P16 tumor suppressor genes in marginal zone B-cell lymphoma: An interphase fluorescence in situ hybridization study.

The genetic mechanisms underlying the genesis, disease progression, and high-grade transformation of marginal zone B-cell lymphoma (MZBCL) are poorly understood. We analyzed 33 cases of histologically and immunophenotypically well-characterized MZBCL (12 extranodal, 11 nodal, and 10 splenic MZBCL; 27 at primary diagnosis and six during the course of disease) by dual-color interphase fluorescence in situ hybridization (FISH) for deletions of tumor suppressor genes. We investigated loci known to play a role in the genesis or disease progression of other subtypes of lymphoid malignancies, namely the P53 gene (17p13), the retinoblastoma gene (RB, 13q14), the D13S25 locus (13q14), and the P16(INK4A) gene (9p21). Heterozygous deletions of P53 were detected in three out of the 33 cases, including two splenic and one extranodal MZBCL. One of these patients was analyzed at primary diagnosis and two during the course of disease. Heterozygous deletions of the RB gene (nodal MZBCL) and D13S25 (splenic MZBCL) were found in one case each. P16 deletions were not detected in any of our cases. We conclude that deletions of the analyzed tumor suppressor genes are relatively rare in MZBCL, which contrasts with the findings in some other subtypes of NHL.

Aged↗

PubMed2006

Aire-deficient mice develop hematopoetic irregularities and marginal zone B-cell lymphoma.

Autoimmune polyendocrine syndrome type I (APS I) is an inherited recessive disorder with a progressive immunological destruction of many tissues including the adrenal cortex, the parathyroid glands, and the gonads. APS I is caused by mutations in the AIRE gene (autoimmune regulator), expressed in cells of the thymus and spleen, suggesting a role in central and peripheral tolerance. Aire(-/-) mice replicate the autoimmune features of APS I patients with the presence of multiple autoantibodies and lymphocytic infiltrates in various tissues, but young mice appear clinically healthy. We here report the investigation of 15- to 24-month-old Aire(-/-) mice. We did not observe any endocrinological abnormalities, nor did sera from these mice recognize known APS I autoantigens. Interestingly, however, there was a high frequency of marginal zone B-cell lymphoma in Aire(-/-) mice and liver infiltrates of B cells, suggesting chronic antigen exposure and exaggerated activation. Furthermore, increased numbers of monocytes in blood were identified as well as augmented numbers of metallophilic macrophages in the spleen. We propose that Aire, in addition to its function in the thymus, also has a peripheral regulatory role by controlling the development of antigen-presenting cells (APCs) and marginal zone B-cell activation.

Animals↗

PubMed2005

Cutaneous lymphoid hyperplasia and marginal zone B-cell lymphoma following vaccination.

Atypical lymphoid infiltrations arose within the influenza inoculation sites of two adult female patients. One patient developed a low-grade cutaneous marginal zone B-cell lymphoma (MZL) that was responsive to local excision and radiation therapy despite spread to a distant cutaneous site. The second patient's clinical course was characterized by a locally aggressive, histologically reactive inflammatory reaction responsive only to radiation therapy after multiple failed attempts at surgical resection.

Aged↗

PubMed2001

Molecular cytogenetic characterization of marginal zone B-cell lymphoma: correlation with clinicopathologic findings in 14 cases.

BACKGROUND AND OBJECTIVES: To improve the definition of the incidence and significance of chromosome lesions occurring in marginal zone B-cell lymphoma (MZBCL). DESIGN AND METHODS: Fourteen cases of MZBCL diagnosed according to the REAL classification were studied by conventional chromosome analysis (CCA) and by interphase fluorescence in situ hybridization (FISH) using the following probes: 3q27/BCL6, 6q21, 7q31, 9p21/p16, 11q22/ATM, 13q14, 17p13, centromeres of #3, #7, #12. Pertinent clinical data were collected. RESULTS: Primary disease presentation consisted of histologically documented splenic MZBCL in 9 cases, nodal MZBCL in 3 cases and extra-nodal MZBCL in 2 cases. Four cases showed evolution into a high-grade lymphoma, due to the presence of a predominant large cell or blast cell component. Clonal karyotype anomalies were detected by CCA in 12 cases, 6 of which had a complex karyotype, including all 4 cases with high-grade histology. Interphase FISH confirmed cytogenetic data and revealed several cryptic chromosomal lesions. Overall, total/partial +12 was found in five cases; 13q14 and 17p13 deletion were found in four cases each; +3, 7q31 deletion and a BCL6 split signal were found in three cases; deletions at 6q21 and 11q22.3 in two cases each; +7 and a 9p21 deletion were found in one case each. INTERPRETATION AND CONCLUSIONS: i) Besides +3 and 7q-, 13q14 deletion, total/partial +12, BCL6 rearrangement, and deletions at 6q21, 11q22-23, and 17p13.3 are relatively frequent events in MZBCL; ii) unlike in mantle cell lymphoma, 9p21 deletion occurred infrequently in MZBCL; iii) a switch into high grade histology is usually associated with complex chromosome defects, including 6q-, 11q-, +12, and 17p.

Adult↗

PubMed1999

Splenic marginal zone B-cell and thymic T-cell lymphomas in p53-deficient mice.

The molecular pathology and histogenesis of lymphomas in 56 retired breeder male and 14 12-week-old male homozygous p53-deficient (p53-/-) mice (C57BL/6TacfBR-[KO]p53 N4) were evaluated. Lymphomas were assessed by serial morphologic techniques, immunohistochemistry, flow cytometry, and analysis of T cell receptor (TCR) or immunoglobulin heavy chain (IgH) gene rearrangements. We found two common types of lymphomas. T-cell lymphomas arose in the thymus through a sequence of lymphocyte depletion, medullary hyperplasia, and unilateral lymphoma. Tumor cells were CD3+, CD90+, and usually TCRalpha/beta+ and possessed clonal TCRbeta gene rearrangements. Thymic lymphoblastic lymphomas (LL) were highly malignant and quickly metastasized to the splenic white pulp and liver, even when the thymus was only slightly increased in weight. In the spleen, a novel lymphoma was found. Marginal zone hyperplasia led to marginal zone lymphoma (MZL), a well-differentiated lymphoma that usually expressed CD45R (B220) and CD5 at low levels and that had clonal IgH gene rearrangements. IgH gene rearrangements were also seen in spleens with marginal zone hyperplasias only. Hyperplastic and neoplastic marginal zone B cells expressed IgM at low to normal levels, as seen by FACS analysis and immunohistochemistry. These tumors only metastasized to the liver at a later stage, as they became less differentiated. Several mice had both types of tumors present in the spleen. Two B-cell lymphoblastic lymphomas of uncertain origin were also found. In this article, we discuss the possible mechanisms responsible for development of the lymphomas seen in these p53-deficient mice.

Animals↗

PubMed2006

Similarities and differences between selective and nonselective BAFF blockade in murine SLE.

B cells have multiple roles in immune activation and inflammation separate from their capacity to produce antibodies. B cell depletion is currently under intense investigation as a therapeutic strategy for autoimmune diseases. The TNF family members B cell-activating factor of the TNF family (BAFF) and its homolog A proliferation-inducing ligand (APRIL) are B cell survival and differentiation factors and are therefore rational therapeutic targets. We compared the effects of BAFF receptor-Ig, which blocks only BAFF, with those of transmembrane activator and calcium modulator ligand interactor-Ig, which blocks both BAFF and APRIL, in a murine SLE model. Both reagents prolonged the life of NZB/W F1 mice when given either before or after disease onset. Many immunologic effects of the 2 reagents were similar, including B cell and B cell subset depletion and prevention of the progressive T cell activation and dendritic cell accumulation that occurs with age in NZB/W mice without substantial effects on the emergence of the IgG anti-double-stranded DNA response. Furthermore, both reagents inhibited the T cell-independent marginal zone B cell response to particulate antigen delivered i.v., but not the B1 B cell response to the same antigen delivered i.p. In contrast, blockade of both BAFF and APRIL, but not blockade of BAFF alone, reduced the serum levels of IgM antibodies, decreased the frequency of plasma cells in the spleen, and inhibited the IgM response to a T cell-dependent antigen. The differences between selective and nonselective BAFF blockade are relevant to the choice of a BAFF blocking agent for the treatment of autoimmune and malignant diseases.

Animals↗

PubMed2003

[Spontaneous regression of MALT lymphoma of the hard palate accompanied by Sjögren syndrome].

A 46-year-old woman visited our hospital in January 1998 because of a painful palate mass. In the ten years previous to presenting, she noticed dryness of the mouth and occasionally had conjunctivitis. The pathological findings of the biopsy from the hard palate revealed that she had an extranodal marginal zone B cell type lymphoma (MALT type). Results of the Schirmer test, rose-bengal test and a gum test all supported the diagnosis that she had also Sjögren syndrome. However, complete self-remission of the hard palate lymphoma was observed 4 months after the diagnosis, and no relapse has been seen in a follow-up of over 2.5 years. Watch and wait should be emphasized for a patient having a palate MALToma at an early stage accompanied by Sjögren syndrome.

Female↗

PubMedDate not supplied

Recent advances in our understanding of the biology and pathogenesis of gastric mucosa-associated lymphoid tissue (malt) lymphoma.

The evolution of gastric mucosa-associated lymphoid tissue (MALT) lymphoma is a multi-stage process, comprising the sequential development of chronic H. pylori-associated gastritis, low grade and high grade lymphoma. The genesis of MALT lymphoma embodies the mechanisms of both physiological immune responses and the acquisition of genetic abnormalities. The tumour probably originates from an autoreactive MALT marginal zone B cell, which is generated during H. pylori infection. As a consequence of a genotoxic insult induced by H. pylori infection, the progenitor tumour cell may become genetically unstable and develop genetic abnormalities such as the t(11;18) translocation, trisomy three, c-myc and p53 mutations during a phase of expansion, which lead to partial transformation. With the growth help from H. pylori specific T cells, this abnormal B cell clone may undergo clonal expansion and gradually form a low grade MALT lymphoma. Additional genetic abnormalities including the t(1;14) translocation and other uncharacterised events could completely transform this abnormal B cell clone and result in escape from T cell dependency. Finally, further genetic events such as complete inactivation of the tumour suppressor genes p53 and p16, and possible activation of c-myc oncogene by translocation or other undetermined abnormalities can result in high grade transformation

Cell Transformation, Neoplastic↗

PubMed2001

MALT lymphoma originating in breast and uvula.

A case of marginal zone B cell lymphoma of MALT type arising in the uvula and breast is reported. The patient, a 30-year-old woman who delivered a child and lactated in 1997, was suffering from Sjögren syndrome (SS). She was diagnosed with MALT lymphoma after a biopsy of the right breast and uvula. To investigate the relationship of the delivery, lactation and MALT lymphoma, we examined the immunohistochemical analysis of hormone receptors. As a result, lymphoid cells of the breast were stained with anti-progesterone receptor antibodies in the cytoplasm. Consequently, the MALT lymphoma of the uvula appeared to be associated with SS. Moreover, hormones such as progesterone may have influenced the breast involvement of MALT lymphoma in our case.

Adult↗