Angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) is a peculiar T cell lymphoma, as expanding B cell clones are often present besides the malignant T cell clones. In addition, large ...numbers of Epstein-Barr virus (EBV)-infected B cells are frequently observed. To analyze the differentiation status and clonal composition of EBV-harboring B cells in AILD, single EBV-infected cells were micromanipulated from lymph nodes of six patients with frequent EBV(+) cells and their rearranged immunoglobulin (Ig) genes analyzed. Most EBV-infected B cells carried mutated Ig genes, indicating that in AILD, EBV preferentially resides in memory and/or germinal center B cells. EBV(+) B cell clones observed in all six cases ranged from small polyclonal to large monoclonal expansions and often showed ongoing somatic hypermutation while EBV(-) B cells showed little tendency for clonal expansion. Surprisingly, many members of expanding B cell clones had acquired destructive mutations in originally functional V gene rearrangements and showed an unfavorable high load of replacement mutations in the framework regions, indicating that they accumulated mutations over repeated rounds of mutation and division while not being selected through their antigen receptor. This sustained selection-free accumulation of somatic mutations is unique to AILD. Moreover, the survival and clonal expansion of "forbidden" (i.e., Ig-deficient) B cells has not been observed before in vivo and thus represents a novel type of viral latency in the B cell compartment. It is likely the interplay between the microenvironment in AILD lymph nodes and the viral transformation that leads to the survival and clonal expansion of Ig-less B cells.
Research on prognostically relevant immunohistochemical markers in diffuse large B-cell lymphomas has mostly been performed on retrospectively collected clinical data. This is also true for ...immunohistochemical classifiers that are thought to reflect the cell-of-origin subclassification of gene expression studies. In order to obtain deeper insight into the heterogeneous prognosis of diffuse large B-cell lymphomas and to validate a previously published immunohistochemical classifier, we analyzed data from a large set of cases from prospective clinical trials with long-term follow-up.
We performed morphological and extensive immunohistochemical analyses in 414 cases of diffuse large B-cell lymphoma from two prospective randomized clinical trials (NHL-B1/B2, Germany). Classification into germinal center and non-germinal center subtypes of B-cell lymphoma was based on the expression pattern of CD10, BCL6, and IRF4. Multivariate analyses were performed adjusting for the factors in the International Prognostic Index.
Analyzing 20 different epitopes on tissue microarrays, expression of HLA-DR, presence of CD23(+) follicular dendritic cell meshworks, and monotypic light chain expression emerged as International Prognostic Index-independent markers of superior overall survival. Immunoblastic morphology was found to be related to poor event-free survival. The non-germinal center subtype, according to the three-epitope classifier (CD10, BCL6, and IRF4) did not have prognostic relevance when adjusted for International Prognostic Index factors (relative risk=1.2, p=0.328 for overall survival; and relative risk=1.1, p=0.644 for event-free survival).
The previously reported International Prognostic Index-independent prognostic value of stratification into germinal center/non-germinal center B-cell lymphoma using the expression pattern of CD10, BCL6, and IRF4 was not reproducible in our series. However, other markers and the morphological subtype appear to be of prognostic value.
To study the distribution pattern of interleukin-6 (IL-6)-producing cells in normal human lymph nodes, we applied the in situ reverse transcription-polymerase chain reaction technique. We describe a ...new modification of this technique for monitoring small amounts of specific nucleotide sequences in conventional paraffin sections. This technique differs in at least two respects from those described earlier. The two decisive steps are: 1) the reverse transcription of mRNA and the subsequent amplification of cDNA by polymerase chain reaction are performed by a new single enzyme capable of both reaction types in one and the same medium without buffer exchange; and 2) for the specific detection of the amplified cDNA, a modified version of the primed in situ labeling technique was used. The technique, carried out on normal human lymph nodes, traces a low load of IL-6 mRNA in fibroblasts, endothelial cells, and a minor population of T lymphocytes in the pulp region. High levels of expression were encountered in about 20% of perisinusoidal pulp macrophages. In addition, moderate activity was detectable in sinus lining cells. Because no major activity was found in the germinal centers of the lymphoid B follicles and in the T zone, it is suggested that the plasma cell differentiation ensuing from primary and secondary B-cell immunization is mainly effected by the sinus lining cells as well as perifollicular and perisinusoidal pulp macrophages capable of producing high amounts of IL-6.
We report five novel monoclonal antibodies (Ki-S1, Ki-S4, Ki-S6, Ki-S7, and Ki-S8) reactive with a proliferation-related nuclear antigen. In immunoprecipitation and Western blot experiments using ...crude nuclear extracts, they recognized a protein of 170 kD that, after proteolytic digestion of the immunoprecipitate and sequencing of the resulting peptides, was identified as the α-isoform of human topoisomerase II. This was confirmed by testing the antibodies on a highly purified enzyme preparation. Crossreactivity with topoisomerase IIβ was ruled out by testing the antibodies on crude extracts from yeast cells expressing the β-isoform exclusively. The antibodies bind the antigen with different affinities and at different epitopes, apparently located within the carboxyl third of the enzyme. All five antibodies are suitable for archival material after adequate antigen retrieval, thereby enabling retrospective studies. This report illustrates the tissue and subcellular distribution of the antigen through the cell cycle by immunohistochemistry and confocal fluorescence microscopy. The antibodies will be useful tools in further analysis of morphological and functional aspects of topoisomerase II and may serve diagnostic purposes, as well as providing prognostic information in tumor pathology.
In the immunobiological characterization of lymph node cells, sinus-lining cells (SLCs) have been given little attention mainly due to the difficulties in their recognition. Ki-M9 is a new monoclonal ...antibody (MAb) selected for its unique capability to visualize SLCs in human lymph nodes. The details were established by light and electron microscopy and immunoprecipitation of the corresponding biosynthetically labeled antigen. Ki-M9 recognizes a 70-kd protein localized on the surface membrane of SLCs. In the lymphoid tissue, a mild reactivity was exclusively encountered on follicular dendritic reticulum cells in the germinal centers of secondary lymphoid follicles. In other organs, some squamous epithelial and myoepithelial cells were recognized by this antibody. Immunomonitoring of SLCs on light and electron microscopic levels revealed their dendritic morphology, lack of phagosomes, and their close association with type IV collagen fibers. Considering the occurrence of typical dendritic SLCs on the front line of antigen flood, we propose that SLCs be investigated for a possible antigen-binding property.
To analyze the long-term results following whole brain radiotherapy (WBRT) with sequential intrathecal (i.th.) cytosine arabinoside (Ara-C) +/- intravenous (i.v.) Ara-C in patients with primary ...central nervous system lymphoma (PCNSL).
14 patients were treated between July 1987 and August 1995. All had sporadic PCNSL with proven histology of high-grade CNS lymphoma (twelve diffuse large-cell B-lymphomas, one lymphoblastic lymphoma, one large T-cell lymphoma). Patients were treated with two to four cycles of induction chemotherapy (40 mg/m2 Ara-C i.th.), four patients received additional Ara-C i.v. (150 mg/m2, d1-4). WBRT was administered using 1.8-Gy fractions. Intrathecal chemotherapy was planned afterwards in 4-week intervals for 6 months. Posttreatment neurocognitive evaluations were performed in two long-term survivors.
Two of four patients who received i.v. and i.th. induction chemotherapy showed progressive disease, and irradiation was started immediately. Six of 14 patients received 50.4 Gy WBRT, four patients had WBRT up to 39.6 Gy followed by a 10.8-Gy boost. Five patients died early during therapy either due to a decline of the general medical condition or progressive disease. Median survival was 41 months (95% confidence interval: 6-79 months), survival at 3 and 5 years was 59% and 42%, respectively. Six patients survived for 3 years, two younger patients are still alive (> 12 years). They show only slightly impaired neurocognitive functions without clinical relevance.
This WBRT-based protocol with i.th. meningeal prophylaxis using Ara-C +/- i.v. Ara-C yields substantial long-term survival with moderate toxicity. The value of i.v. chemotherapy is currently being investigated in prospective studies.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Human sinus-lining cells (SLC) of the lymph node sinuses most probably represent accessory cells for the primary humoral immune response and have been shown to express a unique antigen recognized by ...the monoclonal antibody Ki-M9. To characterize this SLC-specific antigen further, a spleen cDNA library established in the expression vector lambda gt-11 was searched immunochemically for clones expressing the Ki-M9 antigen. Two recombinant phage clones revealed a cDNA with an open reading frame of 1666 bp encoding a 68-kDa protein. When fused with an expression vector that codes for the bacterial maltose-binding protein (MBP), the purified MBP-Ki-M9 fusion protein could be clearly detected by Western blot analysis. Furthermore, in situ hybridization with Ki-M9 cDNA as a probe confirmed the SLC-specific expression of the cloned cDNA. Additionally, Ki-M9 mRNA transcripts were detected in follicular dendritic reticulum cells of the secondary germinal centers, in a few cells of the perifollicular zone of the spleen, in some sinusoidal cells of liver, and in thymic reticular cells. A sequence database research revealed a strong homology to a murine cDNA. By applying non-radioactive in situ hybridization on mouse tissue, strong expression in SLC of the lymph node and metallophilic cells of the spleen in mouse tissue could be seen indicating that the Ki-M9 cDNA is highly conserved in the two species. Further computer analysis of the deduced amino acid sequence of the Ki-M9 antigen showed a large number of potential glycosylation sites and a PEST motive, which are characteristic for rapidly degraded membrane bound proteins and represent prerequisites for the function of this cell system in initiating the humoral immune response.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The retinoblastoma gene (RB) is a growth suppressor gene on the human chromosome 13q14. It encodes a 105 kDa phosphoprotein (p105), with DNA-binding capacity. P105 is thought to be involved in cell ...cycle control. Inactivation of RB is responsible for the development of retinoblastomas and occurs frequently in osteosarcomas and small cell lung cancer. In this study we looked at the RB-structure and expression in cell lines and primary lymphoma samples from patients with high grade non-Hodgkin's lymphoma (NHL). Forty five primary high grade NHL, the B-lymphoblastoid cell line IM-9 and the NHL cell line WSU-NHL were studied for RB structure by Southern blotting and for RB-expression by Northern blotting, Western blotting and immunocytochemistry. In all experiments freshly cryopreserved material was used. Southern and Northern experiments were performed with the 0.9 kb and 3.8 kb RB-cDNA probe. For the detection of p105 two different anti-p105-monoclonal antibodies were used in immunocytochemistry and Western blotting experiments. No RB mRNA and no p105 could be found in IM-9 cells. Twenty six high grade NHL samples (58%) showed no p105 expression. In the subgroup of centroblastic lymphomas 16 out of 21 and in Burkitt's lymphomas five out of eight showed no p105-expression. P105 expression is absent in 58% of high grade NHL, particularly in centroblastic and Burkitt's lymphomas, suggesting that inactivation of RB may play a crucial role in the pathogenesis of high grade NHL.
In vitro data have demonstrated autologous T-lymphocytes with anti-tumour activity in multiple myeloma (MM). Therefore a phase I/II trial was conducted to study the feasibility, the effect on several ...immunological parameters, and the tumour response induction of low-dose recombinant interleukin-2 (rIL-2) in MM patients. 18 MM patients of advanced stages in progress, who had failed on standard chemotherapy received 9 x 10(6) IU/m2 rIL-2 twice daily on days 1 and 2 and 0.9 x 10(6) IU/m2 twice daily for 5 subsequent days per week subcutaneously from days 3 to 56 (repeated every 12 weeks until progression). Patients were treated for between 8 and 1086 + d (mean 241 d) without serious side-effects. 6/17 patients experienced tumour response (2/17 objective tumour mass reduction, 4/17 long-lasting stable disease following tumour progression before initiation of rIL-2 treatment). During therapy the number of eosinophils increased 15-fold, CD4+ T lymphocytes were activated as demonstrated by enhanced CD25 antigen expression, and CD56+ NK cells expanded in the peripheral blood. Furthermore, a diminished pre-treatment ratio of CD4+/CD8+ lymphocytes was normalized during rIL-2 treatment. NK cell activity and lymphokine activated killer (LAK) cell activity was significantly enhanced. Endogenous IL-2 production and elevated soluble IL-2 receptor serum concentrations were induced. Low-dose rIL-2 can stimulate immune enhancement in MM despite the characteristic tumour-induced immunodeficiency. The treatment has proven though limited efficacy in advanced MM. Because most of the responders experienced termination of tumour progression rather than tumour regression, rIL-2 maintenance of chemotherapy-induced remissions should be investigated.
To analyze the transition of an autoimmune disease into a mucosa-associated lymphoid tissue-non-Hodgkin's lymphoma (MALT-NHL), we investigated a total of 27 cases of clinically diagnosed autoimmune ...thyroiditis with lymphoid hyperplasia. Three cases of thyroid hyperplasia served as controls. Monoclonal B cells were detected by studying rearrangement patterns of the hypervariable CDR III regions within the immunoglobulin heavy chain gene locus and the T-cell receptor gamma chain gene (TCRG). We used a seminested polymerase chain reaction (PCR) to demonstrate immunoglobulin rearrangements and a multiplex PCR for TCRG rearrangements. The PCR products were analyzed by temperature gradient gel electrophoresis to expand mixtures of homo- and hetero-duplices within heterogeneous populations of B cells. With this approach we found monoclonality in 14 of the 27 cases of Hashimoto's disease. In a reinvestigation we discovered additional histological and immunohistochemical features of MALT-NHL in 17 cases. The 14 cases of thyroiditis with clonally expanded B cells clearly demonstrate the transition from autoimmune disease to non-Hodgkin's lymphoma.