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G Delsol

Publications and source records attributed to G Delsol.

At least 127 records · Page 7Linked to original sources
PubMed1995

Oestrogen synthesis, oestrogen metabolism and functional oestrogen receptors in bovine aortic endothelial cells.

In order to investigate the mechanisms by which oestrogenic hormones influence the vascular system, we have studied their metabolism and the functioning of oestrogen receptors in bovine aortic endothelial cells from primo-secondary cultures, a widely studied model of vascular pathophysiology. We have demonstrated the enzymic activity of oestradiol-17 beta-hydroxysteroid dehydrogenase, 17-ketoreductase and aromatase in these cells. Immunocytochemical analyses, using two different monoclonal antibodies that recognize epitopes in the A/B domain of the oestrogen receptor, showed that this molecule has a predominantly cytoplasmic localization even after the addition of oestrogen to the culture medium. We showed that the hormone-receptor complexes were functional by demonstrating their transactivating ability in transfection experiments using the luciferase gene reporter and an oestrogen-responsive element transcriptional enhancer, although the amplitude of the response was in the range of only 140-150%: this was not a consequence of the presence of a specific limiting factor, but instead might be related to the peculiar subcellular localization of the oestrogen receptor.

Animals↗
PubMed1995

Bone marrow involvement in anaplastic large cell lymphoma. Immunohistochemical detection of minimal disease and its prognostic significance.

Bone marrow involvement by anaplastic large cell anaplastic large cell (ALC) lymphoma can be difficult to detect on routine morphologic examination alone. In a series of 42 patients with ALC lymphoma, the authors analyzed: (1) the usefulness of a limited panel of monoclonal antibodies directed against CD30 (Ber-H2, HRS4) and epithelial marrow involvement on routinely processed biopsy specimens; and (2) the prognostic significance of bone marrow involvement as detected on both morphologic and immunohistochemical grounds. On conventional examination, 17% of the patients were found to have bone marrow involvement at diagnosis. However, after immunohistochemical analysis, occult malignant cells were detected in 23% of the patients with negative bone marrow biopsy on routine histology. The low percentage of positive cases on routine morphologic examination compared to immunohistochemical examination was related to: (1) the scarcity of neoplastic cells which were scattered among hematopoietic cells; (2) the difficulty of distinguishing malignant cells from immature hematopoietic elements; and (3) the absence of alteration of the reticulin network. The authors observed a significant association between marrow infiltration and the presence of hematologic abnormalities (mostly anemia or cytopenias) at diagnosis, both in children and adult patients. More importantly, a significant lower survival was seen in patients with bone marrow involvement compared to those without bone marrow involvement. Immunohistochemistry with anti-CD30 and anti-EMA antibodies should be performed systematically in bone marrow biopsies from patients with ALC lymphoma to reliably identify the presence of bone marrow involvement that appears to carry a poor prognosis.

Adolescent↗
PubMed1995

Production and characterisation of an antimelanoma monoclonal antibody KBA.62 using a new melanoma cell line reactive on paraffin wax embedded sections.

AIMS--To generate new monoclonal antibodies directed against melanoma associated antigens using a new melanoma cell line, KAL. METHODS--The melanoma cell line was established in culture from a lymph node metastasis of malignant melanoma. Normal Balb/c mice were immunised with KAL cells. Splenocytes were used for fusion experiments using standard techniques. Hybridoma supernatants were tested for antibody binding activity using an indirect immunoperoxidase method on frozen sections from KAL tumour cells xenografted onto nude mice and human tonsils. KBA.62 was selected because of its reactivity with melanocytic proliferations on both frozen and paraffin wax sections. RESULTS--On immunoblotting, KBA.62 reacted with three bands of 140, 135 and 128 kD and two weak bands of 88 and 73 kD. In normal human tissues basal melanocytes in the epidermis did not react with this antibody and only occasional labelling of endothelial cells was noted. Of the human tumours, KBA.62 reacted strongly and uniformly with the majority of benign (21/21) and malignant (75/86) melanocytic proliferations. Staining was localised predominantly to the cell membrane with little or no cytoplasmic reactivity. Negative staining was observed in the majority of human non-melanocytic neoplasms, the exceptions being some carcinomas (11/89), particularly the well differentiated squamous cell type. This, however, was not thought to present a diagnostic problem. CONCLUSIONS--KBA.62 appears to be potentially useful in ascertaining the immunomorphological diagnosis of malignant melanoma in routinely processed paraffin wax sections.

Animals↗
PubMed1995

Estrogen synthesis, estrogen metabolism, and functional estrogen receptors in rat arterial smooth muscle cells in culture.

To investigate the mechanisms by which estrogen hormones influence the vascular system, the metabolism of these hormones and the functionality of estrogen receptors were characterized in rat aortic smooth muscle cells from secondary cultures, a widely studied model of vascular biology. Aromatase, estradiol-17 beta-hydroxysteroid dehydrogenase and 17-ketoreductase enzyme activities were demonstrated in these cells. The presence of functional estrogen receptor could also be demonstrated by estrogen-induced transactivating ability in transfection experiments using the luciferase gene reporter and an estrogen responsive element as transcriptional enhancer although the amplitude of the response was only in the range of 140 to 150%. Immunocytochemical analyses, using monoclonal antibodies that recognize epitopes in the A/B domain of the molecule, showed a predominant cytoplasmic localization of these estrogen receptors, even after estrogen addition to the culture medium. Western blot analysis using antibodies that recognize epitopes in the A/B or F domain gave a mol wt of 67,000. Analysis of the estrogen receptor messenger RNA showed that there was no deletion of the proto-signals for nuclear accumulation. The aromatase and dehydrogenase activity results, coupled with the estrogen receptor immunological, RNA analysis, and transfection data strongly support the contention that rat aortic smooth muscle cells are estrogen target cells. This in vitro model is convenient for studying the mechanisms of action of estrogen hormones that seem very peculiar in this cell population.

17-Hydroxysteroid Dehydrogenases↗
PubMed1995

Polymyositis associated with Ki-1 lymphoma.

We report here a case of acute polymyositis associated with a Ki-1 non-Hodgkin's lymphoma (NHL). This anaplastic large cell malignant lymphoma was a primary T-cell NHL lymphoma of the bone marrow. The malignant cells expressed the CD30 (Ki-1), CD3, and CD4 antigens, the beta chain of the interleukin 2 receptor (CD25), and the betaF1 antigen (alpha/beta T-cell receptor). Chemotherapy and high dose methylprednisolone pulse therapy were initiated. However, no clinical improvement was noticed, because the patient rapidly died of an acute respiratory distress syndrome. To our best knowledge, this represents the first case of Ki-1 lymphoma associated with Polymyositis.

Acute Disease↗
PubMed1994

Persistence of the same viral strain in early and late relapses of Epstein-Barr virus-associated Hodgkin's disease.

Twelve cases of relapsing Hodgkin's disease were investigated for the presence of Epstein-Barr virus (EBV). Of these, 7 cases contained EBV gene products (LMP1, EBER RNA) in the diagnostic Reed-Sternberg cells and variants at first presentation and at relapse(s), whereas 5 cases were negative at both first diagnosis and relapse. Among the 7 EBV-positive cases, material for DNA extraction was available in 2 cases at both diagnosis and relapse(s). Ig and T-cell receptor gene rearrangements displayed a germline configuration in the 2 cases. However, Southern blot analysis of the terminal repeats (TR) of EBV genome showed that, in 1 of the 2 cases, the fragment was of the same size at diagnosis and in the subsequent two relapses (1 early and 1 late). The second case contained monoclonal EBV genome at diagnosis, but the Southern analysis of the TR was negative at relapse. The latent membrane protein (LMP1) sequence analysis confirmed the persistence of a distinctive viral strain in each of the 2 cases with individual abnormalities within the carboxy terminal region (5 point mutations and a 30-bp deletion for the first case and 6 point mutations for the second case). The persistence of a given strain in early and late relapses is evidence towards the view that in Hodgkin's disease such relapses are related to a single residual tumor cell clone.

Adult↗
PubMed1994

Detection of the chromosomal translocation t(11;14) by polymerase chain reaction in mantle cell lymphomas.

The t(11;14)(q13;q32) and its molecular counterpart, BCL1 rearrangement, are consistent features of mantle cell lymphoma (MCL). Rearrangement is thought to deregulate the nearby CCND1 (BCL1/PRAD1) proto-oncogene, a member of the cyclin G1 gene family, and thereby to contribute to tumorigenesis. We and others have previously shown that the BCL1 locus is rearranged in 55% to 60% of MCL patients and that, on chromosome 11, more than 80% of the breakpoints are localized within a 1-kbp DNA segment known as the major translocation cluster (MTC). We have determined the nucleotide sequence for a portion of the MTC region, and constructed chromosome 11-specific oligonucleotides that were in conjunction with a consensus immunoglobulin (Ig) heavy chain joining region (JH) primer used to perform the polymerase chain reaction (PCR) to amplify t(11;14) chromosomal junctional sequences in DNA from 16 MCL patients with breakpoints in the MTC region. 15 of the 16 breakpoints that occurred at the MTC region were amenable to PCR detection. The sizes of the amplified bands, the existence or not of a Sac I site in the PCR products, and nucleotide sequencing of the amplified DNA from four patients showed that the breakpoints share a remarkable tendency to tightly cluster within 300 bp on chromosome 11, some of them occurring at the same nucleotide. On chromosome 14, the breakpoints were localized within the Ig JH. Our findings indicate that a BCL1 rearrangement can be detected using this approach in roughly one half of the MCL patients. This has implications for both the diagnosis and the clinical management of MCL.

Base Sequence↗
PubMed1994

Histiocytic sarcomas and monoblastic leukemias. A clinical, histologic, and immunophenotypical study.

Eight histiocytic sarcomas, identified by examination of more than 2000 malignant lymphomas, are described. For comparison, tumor infiltrates from five monoblastic leukemias were also analyzed. The histiocytic sarcomas were all high-grade malignancies consisting of markedly pleomorphic large cells with many mitotic figures. At presentation, six of the patients had systemic symptoms (fever, fatigue, loss of weight), skin infiltrates, and lymphadenopathy. Despite aggressive chemotherapy, clinical remissions were short, and six patients died of disease .5-48 months (mean, 6.5 months) after diagnosis. The remaining two patients are alive and in partial or complete remission 7 and 12 months after diagnosis. Immunotypic examination showed that all the histiocytic sarcomas were positive for macrophage-related antigens and negative for antigens on B cells, T cells, myeloid cells, epithelial cells, and melanocytes. T-cell receptor and immunoglobulin genes were studied in three cases and were present in a germline configuration. One of the histiocytic sarcomas resembled Langerhans' cells in phenotype and morphology; it was classified as a Langerhans' cell sarcoma. The remaining histiocytic sarcomas did not express accessory cell-associated antigens, but more closely resembled "ordinary" tissue macrophages; they were positive for lysozyme and/or CD68, followed in frequency by CD11c, CD4, CD11b, CDw32, peanut agglutinin receptor, and CD13. Similar features were seen in the monoblastic leukemias. These conditions could only be distinguished from histiocytic sarcoma by clinical and morphologic, rather than immunophenotypic, criteria. Expression of oncoprotein p53 was studied in nine cases and was positive in six of six histiocytic sarcomas and one of three monoblastic leukemias. Rare malignancies show features consistent with the derivation from macrophages. Two entities may be distinguished: those that resemble antigen-presenting accessory cells and those that more closely resemble ordinary tissue macrophages. Recognition of these tumors is important clinically and requires assessment of clinical, morphologic, and immunophenotypic features, supplemented by analysis of T-cell receptor and immunoglobulin genes. Whether (or how) p53 gene mutations are implicated in their pathogenesis will be an important topic for future investigation.

Adolescent↗
PubMed1994

Optimization of immunohistochemical detection of P-glycoprotein in chronic lymphoid disorders.

To optimize the immunohistochemical detection of the multidrug resistance (MDR)-associated P-glycoprotein (P-gp) in chronic lymphoid disorders, the authors compared the sensitivity of three different monoclonal antibodies (MoAb) directed against P-gp (C219, JSB-1, and MRK 16) by using the APAAP technique on four tissue preparations obtained from lymphoid tumors: Cryostat sections, ModAMEX processed sections, frozen cytospin preparations, and fresh cytospin preparations. Tumor samples were obtained from patients with previously treated chronic lymphocytic leukemia (6 cases) or non-Hodgkin's malignant lymphoma (4 cases). Lymph nodes (n = 9), spleen (n = 3), and blood (n = 5) were analyzed. JSB-1 MoAb detected P-gp in 4 of 12 cases (33.3%) on either frozen sections or ModAMEX processed sections, and in 6 of 17 cases (35.3%) on frozen cytospin preparations. The sensitivity of JSB-1 was significantly improved when fresh cytospin preparations were used with an incidence of P-gp positive samples as high as 70.6% (P < .05). C219 MoAb was unreactive with lymphoid cells whatever the technique used, whereas this antibody stained stromal cells. MRK 16 MoAb was equally reactive to JSB-1 on fresh cytospin preparations, but unreactive when the other preparations were used. The specificity of JSB1 MoAb was confirmed by both Western blot analysis and Rhodamine 123 efflux assay. The authors used JSB-1 MoAb on fresh cytospin smears prepared from 28 CLL patients. Overall incidence of P-gp positive cases was 39.2%. Univariate analysis showed that P-gp expression was correlated with prior therapy, refractoriness to treatment, Rai stratification, and time of tissue storage after diagnosis. The authors recommend the use of JSB-1 on fresh cytospin preparations for the immunocytochemical detection of P-gp in chronic lymphoid disorders.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

Nodular lymphocyte predominance Hodgkin's disease. A distinct clinicopathological entity.

This article reviews the evidence that the nodular form of lymphocyte predominance Hodgkin's disease ("nodular paragranuloma") should be recognised as a distinct clinico-pathological entity. The disease is characterised histologically by very large primary lymphoid follicles, containing polytypic small B lymphocytes and extensive meshworks of follicular dendritic cells. The "L and H" or "popcorn" cells scattered within the nodules show clear differences from classical Reed-Sternberg cells, both in their cytological appearance and in their marker profile, being frequently negative for CD15 and for the EBV genome, but often positive for B cell antigens, CD45 (leucocyte common antigen), CDw75 (LN1), epithelial membrane antigen (EMA) and J chain. These findings suggest that L and H cells may be Ig-synthesising monoclonal B cells. Nodular lymphocyte predominance Hodgkin's disease pursues a much more indolent courses that classical Hodgkin's disease, and long term survival is common. It has other distinctive clinical features, e.g. a unimodal age distribution, a predilection to involve single lymph nodes, and a very low incidence of thymic involvement. There is a tendency for diffuse large cell non-Hodgkin's lymphoma, usually of B cell type, to develop during the course of the disease. This type of Hodgkin's disease thus has many features that distinguish it from the nodular sclerosis and mixed cellularity varieties, and it is hoped that future studies will gather more information on its clinical behavior and on the nature of the putative neoplastic cells, as well as exploring different protocols for its treatment.

Hodgkin Disease↗
PubMed1994

Epstein-Barr virus (EBV) replicative gene expression in tumour cells of AIDS-related non-Hodgkin's lymphoma in relation to CD4 cell number and antibody titres to EBV.

OBJECTIVE: To determine whether activation of Epstein-Barr virus (EBV) replication in tumour cells of AIDS-related non-Hodgkin's lymphoma (ARNHL) is correlated with CD4+ cell counts and influences antibody response to EBV [anti-Z Epstein-Barr replicative activator (ZEBRA), anti-early antigen (EA), anti-viral capsid antigen (VCA)]. DESIGN: Retrospective study based on immunohistochemistry and in situ hybridization to detect EBV replicative gene products in tissue samples from patients affected by ARNHL and correlation with CD4+ cell counts and results of EBV serology (including anti-ZEBRA activity) in sera from the same patients. METHODS: Seventeen out of 22 cases of ARNHL were selected for the presence of EBV [Epstein-Barr early region (EBER) RNA-positive]. Immunohistochemistry was performed with anti-ZEBRA, anti-EA-restricted, anti-VCA antibodies and in situ hybridization with BHLF1/NotI oligoprobes on tumour samples. Results were statistically correlated with those of CD4+ cell counts (17 out of 17) and with anti-EBV antibody titres (13 out of 17) assessed using standard immunofluorescence method and enzyme-linked immunosorbent assay procedure using recombinant ZEBRA protein and synthetic peptides as antigens. RESULTS: BZLF1 (ZEBRA) or early gene products (EA-R and EA-D/BHLF1/NotI) were detected in a small proportion (< 0.01-5%) of tumour cells in eight of these 17 cases by immunohistochemistry and in situ hybridization. Demonstration of replicative gene expression did not correlate with either low CD4+ cell counts (P > 0.05) or anti-EBV antibody titres (P > 0.05). Anti-ZEBRA activity was not significantly increased in patients affected with ARNHL, the cells of which expressed replicative gene products (P > 0.05). CONCLUSION: The degree of immunodeficiency does not clearly enhance replicative gene expression in tumour cells of ARNHL. EBV serology, including anti-ZEBRA activity, is not a reliable tool for predicting the occurrence of such proliferations.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Lack of restricted T-cell receptor beta-chain variable region (V beta) usage of reactive T-lymphocytes in Hodgkin's disease.

T-cell response against tumour-associated antigens is mediated by the TCR complex. To determine a possibly restricted TCR-V beta repertoire in reactive T-lymphocytes in Hodgkin's disease (HD), 20 cases (of which 10 were EBV-positive cases) were investigated using 14 monoclonal antibodies (MoAbs) recognizing 11 different TCR-V beta region family products and Northern blot analysis with cDNA probes specific for mRNA transcripts of 11 V beta families that were not detectable by MoAbs. Four V beta families (V beta 5, V beta 6, V beta 8, V beta 19) were investigated using both immunohistochemistry (IHC) with anti-V beta MoAbs and Northern blot analysis. Immunohistochemical and Northern blot findings were correlated with the detection of the Epstein-Barr virus (EBV) genome in Hodgkin's and Reed-Sternberg cells (H-RS). The non-neoplastic lymphocytes in HD were predominantly of T-phenotype (CD3+). Most of these cells were TCR-alpha beta+ (beta F1+) and only a few T-cells were reactive for TCR-delta 1 antibody (TCR-gamma delta+). In the majority of cases helper/inducer T-cells (CD4+) outnumbered suppressor/cytotoxic T-cells (CD8+). Labelling of these samples with the panel of 14 anti-V beta MoAbs showed that only a small percentage (0.2-5.5%) of beta F1+ lymphocytes were positive with each of these MoAbs. The proportion of these cells was comparable to that seen in normal tissues. Most TCR V beta+ cells were randomly distributed, but in virtually all cases occasional V beta+ cells pertaining to the various V beta families were seen in close contact to H-RS cells. Using total RNA extracted from malignant and normal tissues, no visible band was detected with the various V beta probes. As determined in the present study, the percentage of T-cells expressing a given V beta family must be > or = 10% to be detected with Northern blot. Thus, the percentage of V beta+ cells expressing V beta families which were explored only with Northern blot were within the same range as those of the 11 different TCR-V beta region families assessed with IHC, i.e. 1-10% of lymphoid cells. The results of the present study show that in HD there is no restricted T-cell V beta repertoire usage regardless of the detection of EBV. In addition, since the various V beta families are represented in T-cell subpopulations forming rosettes around H-RS cells, we conclude that the T-cells attracted by H-RS cells constitute a polyclonal population.

Antigens, Neoplasm↗
PubMed1994

Epstein-Barr virus in familial Hodgkin's disease.

Hodgkin's disease (HD) has been found to be linked to Epstein-Barr virus (EBV). Familial HD (FHD) may be related to a possible unknown agent. We have determined whether EBV small RNAs (EBERs) were found in Reed-Sternberg cells from FHD. Five families were studied for histological subtype and EBER presence. There was a striking similarity in FHD subtypes of each family and 3/11 (27%) of the cases were EBER positive. In conclusion, EBV EBERs are only infrequently found in FHD and other factors including viruses different from EBV should be further investigated in FHD.

Female↗
PubMed1994

A proposal for classification of lymphoid neoplasms (by the International Lymphoma Study Group).

A new classification of lymphoid neoplasms, mostly based on existing terminology, is proposed by the International Lymphoma Study Group. The proposed classification was reached through a consensus of the members, despite their diverse backgrounds, and consists of a listing of currently recognized clinicopathological entities. These tumours are divided into three major categories: B-cell neoplasms, T-cell and postulated natural killer cell neoplasms, and Hodgkin's disease. The characterization of each entity is based on a synthesis of all available information. This concept departs from a purely morphological approach to lymphoma classification, which is considered to be inadequate, because many biologically distinctive lymphoma types can exhibit a broad and overlapping morphological spectrum. Some entities are provisional, pending further data to confirm that their recognition is reproducible. The salient clinicopathological features of each entity are summarized in this review.

Hodgkin Disease↗