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71.
By prospectively studying immunoglobulin heavy chain gene (IgH) and T cell receptor gamma (TCRgamma) gene rearrangements in 398 lymphoma cases, a dual genotype was observed in 13% of B cell and 11% of T cell lymphomas. According to histological subtype, the highest incidence was observed for mantle cell lymphomas (32%) and lymphoplasmacytic lymphoma (21%) among B cell lymphomas, and for angioimmunoblastic lymphoma (AILT) (46%) and Sézary syndrome (SS) (50%) among T cell lymphomas. To determine whether the dual genotype corresponds to the presence of two distinct monoclonal populations or to the presence of both rearrangements within the same lymphoma cells, single-cell microdissection was used after immunohistochemistry and a single-cell combined IgH and TCRgamma gene analysis was designed after a whole-genome amplification step. This protocol was applied to the study of two nodal B cell lymphomas (one diffuse large B cell lymphoma and one mantle cell lymphoma) and two cutaneous T cell lymphomas (one AILT and one SS). Two cases (SS and mantle cell lymphoma) were true bigenotypic lymphomas, as both IgH and TCRgamma monoclonal rearrangements were detected in the same cells. Conversely, in the diffuse large B cell lymphoma and AILT cases, large CD22+ single cells exhibited only the monoclonal IgH rearrangement but not the TCRgamma gene that was detected in CD3+ single cells. Such an approach allows the identification of true bigenotypic lymphoma among dual genotypic lymphoma. Specific genetic alterations may be further amplified from microdissected cryopreserved material, such as the t(11;14) breakpoint detected in bigenotypic B cells of the mantle cell lymphoma case.  相似文献   
72.
To determine whether primary B-cell gastric lymphoma (GL) is one entity, we examined the expression of three adhesion molecules in the microvasculature of lymphomas. Stromal cells, including vascular endothelial cells, within lymphoid follicles of the gastric mucosa were also investigated. Twenty-two surgical specimens of GL were classified into low-grade malignant lymphoma arising from mucosa-associated lymphoid tissue (low-grade lymphoma, n=9), and high-grade malignant lymphoma with (secondary high-grade lymphoma, n=6) or without (primary high-grade lymphoma, n=7) a low-grade component. The proportion of venules positive for ELAM-1 or VCAM-1 was significantly higher (P<0.001) in primary high-grade lymphoma than in low-grade and secondary high-grade lymphomas. In gastric lymphoid follicles, the stromal cells of the germinal centre (GC) were positive for ICAM-1, ELAM-1, and VCAM-1, but the stromal cells of the marginal zone (MZ) were positive only for ICAM-1. We found two patterns of adhesion molecule expression in gastric lymphoid follicles, the MZ pattern and the GC pattern. Low-grade and secondary high-grade lymphomas, which had the MZ pattern, might be of MZ-cell lineage, but most primary high-grade lymphomas, which had the GC pattern, might be of follicular centre cell lineage.  相似文献   
73.
Diffuse large B-cell lymphoma of the testis is a rare tumour, often with disseminated disease. According to the Kiel Classification, these lymphomas are of centroblastic or immunoblastic type, corresponding in the Working Formulation to malignant lymphoma, large cell non-cleaved and large cell immunoblastic, respectively. Adhesive cell-cell and cell-matrix interactions are generally assumed to play an important part in the metastatic process, and to find clues to the highly malignant biological behaviour of this tumour we examined expression of integrins and other adhesion molecules on the tumour cells and the presence of matrix proteins. Few adhesion molecules appeared to be expressed. CD44 was expressed in 10/12 lymphomas, CD49f/VLA-6 was positive in 5/12 cases, and CD49d/VLA-4, CD54 and CD62L were detectable in a small number (2–3) of lymphomas. All other adhesion molecules were lacking. This expression pattern is suggestive of a high metastatic potential: the tumour cells seem to be poorly attached to the extracellular matrix, to each other and to other cells (CD54-, CD11a-, CD58-). The adhesion molecules expressed, CD44, CD49f/VLA-6 and CD49d/VLA-4, have been reported to play a part in dissemination, mediating intravasation (CD49f/VLA-6) and extravasation (CD44, CD49d/VLA-4). This profile of adhesion molecules may explain, at least in part, the specific biological behaviour of these lymphomas with early and rapid dissemination.  相似文献   
74.
Primary cutaneous B-cell lymphoma in Japanese patients   总被引:1,自引:0,他引:1  
Primary cutaneous B-cell lymphoma (PCBCL) is a rare group of lymphoproliferative disorders. There have been few reports of Japanese patients with PCBCL, so the present study investigated the clinicopathological and immunological features and Bcl-2 gene rearrangement and protein expression in 28 Japanese patients with PCBCL. According to the Revised European-American Lymphoma (REAL) classification, there were 25 diffuse large B-cell lymphomas (DLBCL), one Burkitt type lymphoma, one lymphoblastic lymphoma and one marginal zone cell lymphoma. Of the 25 DLBCL, 17 were in males and eight in females, with an average age of 69.4 years. Follow-up data were available in 19 cases of DLBCL of which seven died and 12 were alive. The overall 5-year survival rate was 61%. Cases of DLBCL involving the legs were found to have poorer clinical outcomes; two of four cases with leg lesions died, with a mean survival of 13 months. Of 14 cases with non-leg lesions, four died, and the mean survival was 38.9 months. Only one case of Burkitt type lymphoma was CD10 positive. Bcl-2 rearrangement was not observed in 13 cases studied by polymerase chain reaction. Bcl-2 expression was observed in nine of 13 cases studied. All five cases with leg lesions exhibited Bcl-2 expression, but four of six cases with non-leg lesions also expressed the protein. These results show that DLBCL is the most frequent subtype of PCBCL in Japanese patients and that the prognosis of Japanese patients with DLBCL is worse than that of reported European cases. The study also found that PCBCL was frequently associated with Bcl-2 expression, which was not site-confined, and that there was no evidence for a follicular center origin of PCBCL.  相似文献   
75.
A pilot study is reported of HLA-A, B, and C antigens in 141 East African Blacks comprising patients with Burkitt's lymphoma or nasopharyngeal carcinoma, either with active disease or in long-term remission, together with comparable controls. This study forms part of a wider program investigating host factors in these diseases. A protocol was selected for optimal testing of cells processed and cryopreserved between 1972 and 1976, largely under field conditions, which employed a two-color fluorochromasia typing procedure. Antigen distribution and computed haplotype frequencies in the total unrelated population are given. New findings include an approximately equal frequency of Aw23 and Aw24, a high (18%) incidence of Bw21, and the gametic associations of Aw36 with Bw44, and Aw30 with Bw45. Of the major group of B15-related antigens reported earlier, SV is the most common, and there are strong linkages of SV with Cw2 and Bw with Cw3. The possible presence of further variants at the A- and B-loci is reported. The proportion of B-locus antigen “blanks” in this study is 5.9%. Relationships have been sought between the HLA antigens and diseases studied: the antigen A29, possibly in linkage with Bw42, shows a correlation with disease susceptibility, and associations are suggested between Bw44 (in possible combination with Aw36) and resistance to both BL and NPC, and between Bw45 and long-term remission in NPC.  相似文献   
76.
Neoplasms of histiocytes and dendritic cells are rare, and their phenotypic and biological definition is incomplete. Seeking to identify antigens detectable in paraffin-embedded sections that might allow a more complete, rational immunophenotypic classification of histiocytic/dendritic cell neoplasms, the International Lymphoma Study Group (ILSG) stained 61 tumours of suspected histiocytic/dendritic cell type with a panel of 15 antibodies including those reactive with histiocytes (CD68, lysozyme (LYS)), Langerhans cells (CD1a), follicular dendritic cells (FDC: CD21, CD35) and S100 protein. This analysis revealed that 57 cases (93%) fit into four major immunophenotypic groups (one histiocytic and three dendritic cell types) utilizing six markers: CD68, LYS, CD1a, S100, CD21, and CD35. The four (7%) unclassified cases were further classifiable into the above four groups using additional morphological and ultrastructural features. The four groups then included: (i) histiocytic sarcoma (n=18) with the following phenotype: CD68 (100%), LYS (94%), CD1a (0%), S100 (33%), CD21/35 (0%). The median age was 46 years. Presentation was predominantly extranodal (72%) with high mortality (58% dead of disease (DOD)). Three had systemic involvement consistent with 'malignant histiocytosis'; (ii) Langerhans cell tumour (LCT) (n=26) which expressed: CD68 (96%), LYS (42%), CD1a (100%), S100 (100%), CD21/35 (0%). There were two morphological variants: cytologically typical (n=17) designated LCT; and cytologically malignant (n=9) designated Langerhans cell sarcoma (LCS). The LCS were often not easily recognized morphologically as LC-derived, but were diagnosed based on CD1a staining. LCT and LCS differed in median age (33 versus 41 years), male:female ratio (3.7:1 versus 1:2), and death rate (31% versus 50% DOD). Four LCT patients had systemic involvement typical of Letterer-Siwe disease; (iii) follicular dendritic cell tumour/sarcoma (FDCT) (n=13) which expressed: CD68 (54%), LYS (8%), CD1a (0%), S100 (16%), FDC markers CD21/35 (100%), EMA (40%). These patients were adults (median age 65 years) with predominantly localized nodal disease (75%) and low mortality (9% DOD); (iv) interdigitating dendritic cell tumour/sarcoma (IDCT) (n=4) which expressed: CD68 (50%), LYS (25%), CD1a (0%), S100 (100%), CD21/35 (0%). The patients were adults (median 71 years) with localized nodal disease (75%) without mortality (0% DOD). In conclusion, definitive immunophenotypic classification of histiocytic and accessory cell neoplasms into four categories was possible in 93% of the cases using six antigens detected in paraffin-embedded sections. Exceptional cases (7%) were resolvable when added morphological and ultrastructural features were considered. We propose a classification combining immunophenotype and morphology with five categories, including Langerhans cell sarcoma. This simplified scheme is practical for everyday diagnostic use and should provide a framework for additional investigation of these unusual neoplasms.  相似文献   
77.
Multiple lines of evidence have revealed a key role for inhibitory Fc gamma receptors class IIb (FcgammaRIIb) as negative modulators of innate and adaptive immune responses. Acquired and genetic factors regulate the expression of FcgammaRIIb receptors and modify their inhibitory potential. Recent advances have highlighted the importance of FcgammaRIIb receptors in influencing the development of cancer and autoimmunity. The association of increased FcgammaRIIb expression with tumor development is believed to operate at effector cell level resulting in inhibition of antitumor cytotoxicity. In autoimmune diseases, FcgammaRIIb receptors play a major role in controlling the amplitude of antibody- and immune complex-mediated reactions. Generally, FcgammaRIIb deficiency is associated with increased susceptibility and severity to organ-specific and systemic autoimmunity. This article discusses the proposed mechanisms for FcgammaRIIb deregulation associated with malignant and autoimmune pathology in animal models and human diseases.  相似文献   
78.
An Epstein-Barr virus (EBV)-producer line, designated Akata, was established from a Japanese patient with Burkitt's lymphoma. The Akata line possessed the Burkitt's-type chromosome translocation, t(8q-; 14q+), and was derived from the tumor cell. Akata cells produced a large quantity of transforming virus upon treatment of cells with anti-immunoglobulin antibodies (Takada, 1984). Southern blot analysis of viral DNA indicated that the Akata EBV is nondefective and more representative of wild-type viruses. Akata cells should be useful as a source of EBV.  相似文献   
79.
A case Is presented of intermediate lymphocytic lymphoma seen In a 53 year old mate, which extensively Infiltrated systemic organs, Including the entire digestive tract from the esophagus to the rectum. Payer's patch Invasion was evident. Multiple Intestinal perforations caused death 5 months later. Surface marker studies suggested the marginal zone origin for this CD2CT B cell malignancy.  相似文献   
80.
Chorionic Villous Biopsy (CVS) for diagnosis of XLP was undertaken at 10 weeks gestation in an obligate carrier. The fetus was found to be male by cytogenetic analysis. XLP (Xq25-q26) is closely linked to the RFLP markers DXS10, DXS37 and DXS42, but only DXS10 (distal to XLP) was informative for prenatal diagnosis in this family. RFLP analysis using this marker gave a 7% risk that the fetus was affected, based on the known recombination frequency between DXS10 and XLP. Further investigation was then undertaken to obtain a rapid and more accurate diagnosis using the three highly polymorphic PCR based markers. These were the AC repeat markers DXS424 (XL5A) and DXS425 (XL90A3) and the tetramer repeat marker within HPRT. DX425 is approximately 10 cM proximal to DXS10 and HPRT but is not known with certainty to map proximal or distal to XLP. DXS424 is proximal to DXS10 and HPRT and was inferred to be proximal to XLP on the basis of map distance from HPRT estimated by linkage analysis of data from CEPH pedigrees. This was confirmed by a recombinant in the XLP family between DXS424 and DXS425, placing DXS424 proximal to XLP. Diagnosis by linkage using DXS424 and DXS425, at least one of which is proximal to XLP, and distal markers DXS10 and HPRT, increased the accuracy of diagnosis using flanking marker analysis to greater than 99% that the fetus was unaffected. HLA DR typing of the CVS showed that the fetus was DR identical to a male sibling with XLP. HLA compatibility was confirmed at delivery by full HLA typing and MLC.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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