BCL6 alternative translocation breakpoint cluster region associated with follicular lymphoma grade 3B

Translocations involving band 3q27, affecting the major breakpoint region (MBR) of BCL6, are common in diffuse large B-cell lymphomas (DLBCLs). Recent data suggest an alternative breakpoint cluster region (ABR) located between 245 and 285 kb 5' of BCL6, which might be associated with Follicular Lymphoma (FL). Ten DLBCLs and 9 FLs grade 3B with cytogenetic rearrangements at 3q27 were studied by fluorescence in situ hybridization (FISH) to discriminate between breakpoints at the ABR and MBR. Eight DLBCLs contained a breakpoint in the MBR, and 6 FL grade 3B (FL3B) cases contained a breakpoint in the ABR. No specific chromosomal partners could be identified in both groups. Previously published data have suggested that FL3B cases with 3q27 aberrations are closely related to the majority of DLBCLs of germinal center cell origin. However, our findings suggest that the mechanism of 3q27 rearrangement in FL3B cases is similar to the mechanism in follicular lymphomas grade 1,2, and 3A cases.     

Common Acute Lymphoblastic Leukemia-associated Antigen (CALLA)-positive B cell lymphoma

We analyzed the expression of common acute lymphoblastic leukemia associated antigen (CALLA) in 134 cases of non Hodgkin's lymphoma of the B cell type using an immunohistochemical method. The incidence of CALLA expression in B cell lymphomas was higher in follicular lymphomas (29%) than in diffuse lymphomas (15%). Malignant lymphoma (ML), follicular small cleaved cell (FSC) according to the histologic type, showed a considerably high incidence of CALLA (43%), whereas ML, diffuse small cleaved cell (DSC) displayed a very low incidence (5%). These findings suggest the possibility that these two morphologically similar lymphomas may be derived from distinct populations of B cells [CALLA⁺-germinal center (GC) cells, CALLA⁻-germinal center (GC) cells or mantle zone (MZ) cells]. In addition, one case of DSC expressed surface immunoglobulin D (SlgD) and alkaline phosphatase (ALPase) as well as CALLA. This indicates that CALLA-positive small cleaved cell lymphoma expressing SlgD or ALPase may represent neoplastic proliferation of CALLA positive MZ cells of secondary follicles in lymph nodes. Acta Pathol. Jpn. 39: 503∼508, 1989.     

Common acute lymphoblastic leukemia-associated antigen (CALLA)-positive B cell lymphoma

We analyzed the expression of common acute lymphoblastic leukemia-associated antigen (CALLA) in 134 cases of non-Hodgkin's lymphoma of the B cell type using an immunohistochemical method. The incidence of CALLA expression in B cell lymphomas was higher in follicular lymphomas (29%) than in diffuse lymphomas (15%). Malignant lymphoma (ML), follicular small cleaved cell (FSC) according to the histologic type, showed a considerably high incidence of CALLA (43%), whereas ML, diffuse small cleaved cell (DSC) displayed a very low incidence (5%). These findings suggest the possibility that these two morphologically similar lymphomas may be derived from distinct populations of B cells [CALLA+-germinal center (GC) cells, CALLA- -germinal center (GC) cells or mantle zone (MZ) cells]. In addition, one case of DSC expressed surface immunoglobulin D (SIgD) and alkaline phosphatase (ALPase) as well as CALLA. This indicates that CALLA-positive small cleaved cell lymphoma expressing SIgD or ALPase may represent neoplastic proliferation of CALLA-positive MZ cells of secondary follicles in lymph nodes.     

RAG基因与B细胞淋巴瘤

重组活化基因(RAG)在介导抗原受体决定区复杂多样的DNA重组中发挥着重要作用,并可通过:1)RAG综合体识别和切断BCL-2基因致t(14,18)易位;2)RAG1/2协同诱导激活型胞啶脱氨酶作用引起染色体易位;3)RAG2蛋白降解异常导致V(D)J异常重排;4)EB病毒感染导致RAG1/2基因的再表达等方面促进淋巴瘤的发生.     

Primary central nervous system B cell lymphoma with features intermediate between diffuse large B cell lymphoma and Burkitt lymphoma

B cell lymphoma with features intermediate between diffuse large B cell lymphoma and Burkitt lymphoma (DLBCL/BL) is a new lymphoma entity which is recognized in the current World Health Organization (WHO) classification (2008). We report a case of a primary central nervous system lymphoma (PCNSL) with findings consistent with DLBCL/BL. It is characterized by a very aggressive clinical course, and a widespread multifocal involvement of the CNS. Our case shows that a DLBCL/BL can manifest in the CNS alone without any systemic involvement.     

Monocytoid B cell lymphoma.

The clinical, light microscopic, ultrastructural, immunocytochemical and cytogenetic features of a case of monocytoid B cell lymphoma were investigated. The tumour initially affected the cervical and supraclavicular nodes, but 33 months later affected the left parotid salivary gland. The patient had subclinical Sjögren''s syndrome. The neoplastic cells showed characteristic morphological features and had peri- and interfollicular distribution in the node. Immunocytochemically the tumour cells were L26, 4KB5, MB2, CD19, CD20, CD22 and IgM/kappa positive. Prominent plasmablastic plasmacytoid differentiation was present in the recurrent tumour, suggesting an origin from post-follicular B cells. The lymphoma cells showed unusual cytogenetic abnormalities.     

Monoclonal antibodies raised against the idiotype of the murine B cell lymphoma, BCL1 act primarily with heavy chain determinants

Anti-idiotypic antibodies can be used as probes to distinguish neoplastic cells from their normal counterparts. In addition they have been used in the passive therapy of B cell tumors. In this report we describe a panel of 7 rat monoclonal antibodies raised against idiotypic determinants carried by the IgM molecule of the BCL1 lymphoma. The majority (6/7) of these antibodies recognize private idiotypic determinants that are carried on the isolated mu heavy chain of the molecule, and do not require the lambda chain for reactivity. This is unusual for antibodies raised against the idiotype of the whole immunoglobulin molecule, which normally require both chains for reactivity. The antibodies do not, however, bind peptides corresponding to the complementarity determining regions of the mu heavy chain of BCL1. The antibodies perform well in complement mediated cytotoxicity, and, in at least one case, are effective in the passive immunotherapy of BCL1 lymphoma.     

Lymphoepitheloid cell malignant lymphoma (Lennert)

Summary Typical epitheloid cell formations were found in 175 of 500 cases of various types of Hodgkin's disease. No distinctive behaviour was found in cases with epitheloid structures.Close attention has been devoted to a further series of 23 lymphoepitheloid cell malignant lymphomata marked by focal nuclear atypicality in their epitheloid cell granulomas, which destroyed the basic neoplastic structure of the lymph node in many cases, necessitating further biopsy. In this series not only Hodgkin's disease (7 cases) but also some malignant lymphomas of non Hodgkin's types (3 × immunoblastoma, 3 × immunocytoma and 2 × T-lymphoblastoma) were found. In 6 cases only a tentative diagnosis of lymphoepitheloid cell malignant lymphoma could be made.The epitheloid granulomatous reaction tended to disappear gradually in all cases by repeated check-ups, and was apparently a secondary phenomenon. The cause of the epitheloid cell atypia was not evident although it proved to be an important diagnostic feature identifying an independent form of lymphoepitheloid malignant lymphoma. The subsequent development of this lesion suggested a mildly pleiomorphic highly malignant lymphoma, which might be of B cell origin, but was sometimes demonstrably of the T cell series.List of Abbreviations Used HD Hodgkin's disease - ML malignant lymphoma - LML lymphoepitheloid cell LM - RS Reed-Sternberg cells - LH lymphoid-histiocytic (polyploid variant of RS) cells - HE hematoxylin-eosin     

Efficiency of antigen presentation to T cell clones by (B cell X B cell lymphoma) hybridomas correlates quantitatively with cell surface ia antigen expression

A series of B cell hybridomas was used as a model system to assess quantitatively the role of Ia molecules in antigen presentation to allo- or soluble antigen-reactive T cell clones. These hybrid cell lines were established by fusion between the HGPRT-BALB/c B cell lymphoma M12.4.1 and LPS-stimulated spleen blasts from B10.BR (H-2k) mice. Quantitative cellular absorption of appropriate anti-Ia monoclonal antibodies and flow cytofluorometric analyses revealed that the B cell hybridomas examined herein expressed constitutively a number of surface I-Ak or I-Ek molecules that varied in an order of magnitude of 1 to 5. Such quantitative differences could be correlated precisely with (a) the capacity of B cell hybridomas to activate T cell clones to proliferate and/or to produce interleukin 2 in response to E beta k allodeterminant or to poly(Glu60Ala30Tyr10) presented in the context of I-Ak restriction element, and (b) the amount of monoclonal anti-I-Ak antibody required to inhibit antigen presentation to T cell clones. The possible implications of these data are discussed in the context of current models of regulation of Ia antigen expression by antigen-presenting cells.     

Pyothorax-associated lymphoma (PAL): a western case with marked angiocentricity and review of the literature

AIMS: To report a case of pyothorax-associated lymphoma in a non-immunocompromised 78-year-old man with a 45-year history of tuberculous pleuritis and left pleural effusion. Pyothorax-associated lymphoma is a high-grade non-Hodgkin's lymphoma occurring in 2% of patients with long-standing tuberculous pleuritis and pyothorax. Pyothorax-associated lymphoma is frequently Epstein-Barr virus (EBV)-associated, mainly reported in Japan but exceedingly rare in western countries. METHODS AND RESULTS: Histology revealed a high-grade, diffuse large B-cell lymphoma with immunoblastic and plasmacytoid features and marked angiocentricity with focal destruction of the vessel walls. Immunohistochemistry revealed a post germinal B-cell phenotype. RNA in-situ hybridization and molecular analysis showed a latent EBV infection and absence of human herpes virus-8 (HHV-8). CONCLUSIONS: Pyothorax-associated lymphoma represents a rare but distinctive type of diffuse large B-cell lymphoma, with characteristic clinico-epidemiological, immunohistological, and biological features.     

B-1a cell origin of the murine B lymphoma line BCL1 characterized by surface markers and bacterial reactivity of its surface IgM

B cells are divided into two categories: conventional or B-2B cells and B-1B cells, the latter of which are distinguished by their different ontogeny. B cell lymphoma 1 (BCL1), the first-reported case of a spontaneously developed mouse B-lymphoma, expresses CD5, surface IgM, Mac-1, CD43 and low level of B220, and is likely to have B-1a cell origin. However, antigens recognized by IgM produced by the BCL1 cells (BCL1-IgM) have not been identified. Here, we demonstrate that BCL1-IgM reacts with Escherichia coli (E. coli). Our initial finding that several recombinant proteins expressed in E. coli bound to BCL1-B20 prompted us to examine the possibility that BCL1 cells may bind E. coli. Indeed, BCL1 cells bound fluorescein-labeled E. coli. To elucidate the structure on the BCL1 cells responsible for E. coli-binding, we produced a monoclonal antibody capable of inhibiting BCL1 binding to E. coli. The antibody recognizes an idiotypic epitope on the BCL1-IgM. Moreover, polyclonal antibody against IgM and secreted BCL1-IgM purified from the supernatants inhibited BCL1 binding to E. coli. Finally, transfection of non-lymphoid cells with cDNA of heavy and light chains of BCL1-IgM conferred the cells ability to bind E. coli. These results clearly indicate that BCL1-IgM bind E. coli and suggest that BCL1 lymphoma is a typical B-1 cell-derived lymphoma, characterized not only by the surface phenotype, but also by the reactivity of its IgM with commensal bacteria.