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G Delsol

Publications and source records attributed to G Delsol.

At least 145 records · Page 8Linked to original sources
PubMed1994

Usefulness of MIB1 monoclonal antibody in assessing the proliferative index in human bladder carcinoma: comparison with Ki-67 antibody.

The reactivity of MIB1 antibody on routinely processed paraffin sections was compared with that of Ki-67 antibody on frozen sections of 80 transitional cell carcinomas of the bladder. The percentage of labelled cells was expressed as the labelling index. MIB1 labelling indices were higher than those of Ki-67 but for each case the two values were strongly correlated (r = 0.91). Ki-67 and MIB1 indices were also correlated to tumour grade and stage (P < or = 0.001). MIB1 indices determined after both formaldehyde and ethanol based Bouin's fluid fixatives did not show any significant difference. MIB1 antibody staining after microwave oven heating of tissue sections is a simple technique for assessing the proliferative fraction of bladder tumours on fixed material. The use of MIB1 antibody permits retrospective studies and should determine whether the proliferation index in bladder carcinoma has the same prognostic value as demonstrated in other types of neoplasms.

Adult↗
PubMed1994

[Epstein-Barr virus replication in Hodgkin disease].

Epstein-Barr virus (EBV) is present in up to 40% of Hodgkin's disease (HD). The viral genomes remain latent within Reed-Sternberg cells (RS cells), but the recent detection of Zebra protein in rare neoplastic cells of a few EBV+ HD cases, suggests an activation of EBV replication. We have studied fifty HD cases containing EBV genomes and expressing LMP1 protein (including five AIDS-related cases), by immunohistochemistry with anti-Zebra antibodies. Four of these cases (all HIV-) showed Zebra+ tumor cells. One of these four cases showed numerous Zebra+ neoplastic cells (approximately 1% of tumor cells) and positive staining for EA-R protein, thus indicating early gene expression. In situ hybridization with biotinylated BamHI W probe revealed in this case, a signal of unusual strength within some Reed-Sternberg cells, probably related to increased number of EBV genomes, thus suggesting EBV replication. Viral replication was finally confirmed in this case, by the detection of BLLF1 transcripts (encoding for the membrane antigen gp 350/220) using reverse transcriptase and polymerase chain reaction. Thus, a very few Zebra+ neoplastic cells are concerned by viral replication, most of them harboring EBV involved in an abortive, instead of a full lytic cycle. EBV replication in RS cells remains an exceptional event, but may provide clues to immunologic mechanisms of control of viral latency. Clinical implications need further investigations.

Adult↗
PubMed1994

B-cell lymphoma following polycythemia vera: evidence for the involvement of two different clones.

We report here two patients with polycythemia vera (PV) who developed secondary non-Hodgkin's lymphoma (NHL). Both cases were high grade B-cell NHL. Cytogenetic analysis of bone marrow and lymph node was performed in each case and showed numerous chromosomal abnormalities. Of interest, chromosomal abnormalities of the PV and of the NHL clones were different, suggesting the possible involvement of two different clones. A 11q23 breakpoint was common between the two cases and the putative role of this breakpoint in the pathogenesis of the NHLs is discussed.

Aged↗
PubMed1993

Deletions within the LMP1 oncogene of Epstein-Barr virus are clustered in Hodgkin's disease and identical to those observed in nasopharyngeal carcinoma.

This study of 52 European patients with Hodgkin's disease (HD) expressing the latent membrane protein 1 (LMP1) oncogene within diagnostic Hodgkin and Reed-Sternberg (HRS) cells was performed to detect LMP1 isolates carrying deletions and to characterize them at a molecular and histologic level. Deletions were identified in 5 cases, clustered near the 3' end of the LMP1 gene, and histologically associated with numerous HRS cells. DNA sequencing showed homology with the deletions seen in the Asian nasopharyngeal carcinoma (NPC) isolates CAO and 1510. Our findings suggest that partial deletions of the LMP1 oncogene, associated with aggressive behavior in NPC CAO and NPC 1510, occur at a particular localization and confer a proliferative phenotype to lymphoid cells in HD.

Adult↗
PubMed1993

Production of monoclonal antibodies to human estrogen-receptor protein (ER) using recombinant ER (RER).

Two monoclonal antibodies (MAbs), IC5 and ID5, were produced using spleen cells from BALB/c mice immunized with recombinant estrogen-receptor protein (RER). On immunoblotting, both MAbs reacted with the 67-kDa polypeptide chain obtained by transformation of E. coli and transfection of COS cells with plasmid vectors expressing ER. The epitopes of both MAbs were in the N-terminal domain (A/B region) of the receptor. In normal human tissues, IC5 and ID5 reacted with cells known to contain large amount of ER, such as cells of the mammary gland and the uterus. Staining was localized predominantly in nuclei with little or no cytoplasmic reactivity. IC5 and ID5 were unreactive with tissues usually considered to be negative for ER. The reactions of these 2 MAbs were further tested on different tumor types, using immunohistochemical (IHC) method on frozen sections. In breast cancer, a good correlation was found between the results obtained on frozen sections and those using the conventional radioligand dextran-coated charcoal (DCC) assay. Immunostaining with IC5 and ID5 MAbs was also assessed on routinely processed paraffin sections using the antigen-retrieval method. Staining was comparable to that obtained on frozen sections in virtually all the breast carcinomas. Negative reactions were consistently obtained with both antibodies on human neoplasms derived from other non-estrogen-dependent organs. IC5 and ID5 MAbs may thus be of value in routine diagnostic histopathology for assessment of the estrogen-receptor content in human carcinomas.

Animals↗
PubMed1993

[Histogenesis of malignant lymphomas].

The strides achieved by immunohistochemical techniques, the development of monoclonal antibodies and, more recently, molecular biology have brought deep changes in the concept of histogenesis and in the classification of malignant lymphomas. After blockage, each of the cells which mark out the transformation of B and T may give birth to a malignant lymphoma. In most cases lymphoproliferations retain the immunological (differentiation markers) and morphological attributes of the normal cells from which they derive. It is on this corpus of data that the present histogenesis and classifications are resting. However, the complexity of lymphoma histogenesis is related to heterogeneous lymphoid populations which are not a mere division into B and T cells. There are numerous and not yet clearly individualized subpopulations the morphological and antigenic features of which are imperfectly known. On the other hand, the development of in situ hybridization techniques and of molecular biology (PCR) has provided useful data on the aetiology of malignant lymphomas. The latest results obtained suggest that several viruses (Epstein-Barr, HTLV-1, HHV-6) might play a predominant oncogenic role.

Cell Division↗
PubMed1993

Rearrangement and overexpression of the BCL-1/PRAD-1 gene in intermediate lymphocytic lymphomas and in t(11q13)-bearing leukemias.

The t(11;14)(q13;q32) translocation and its molecular counterpart, BCL-1 rearrangement, are consistent features of intermediate lymphocytic lymphoma (ILL). Rearrangement is thought to deregulate the nearby PRAD-1/BCL-1 proto-oncogene that is a newly identified member of the cyclin family. To characterize further the association between rearrangement of chromosome 11q13 and over-expression of BCL-1. Southern blot analysis was performed in 33 cases of ILL, 5 cases of t(11;14)-associated leukemias, and 1 case of leukemia carrying a variant translocation t(11;19)(q13;q13) using three separate BCL-1 locus probes. When RNA was available, BCL-1 expression was assessed by Northern blot analysis. DNA from 19 of 33 ILL (57%) showed BCL-1 rearrangement, 16 involving the major translocation cluster (MTC) region and 3 involving a new breakpoint cluster located in the 5' flanking region of the BCL-1 gene. DNA from 3 of 6 t(11q13)-associated leukemias demonstrated a rearrangement involving the MTC. Northern blot analysis showed that BCL-1 was overexpressed in 14 of 15 ILL and in all leukemias analyzed (included the t(11;19) leukemia) relative to normal and malignant lymphoid tissues. These results constitute additional elements in favor of the role of BCL-1 in lymphoid neoplasia and allow us to speculate about its mechanisms of activation.

Aged↗
PubMed1993

Expression of the Ig-associated heterodimer (mb-1 and B29) in Hodgkin's disease.

Eighty-three cases of Hodgkin's disease were studied immunocytochemically for the presence of the Ig associated heterodimer (mb-1 and B29) which is believed to be a specific pan B-cell marker. These results were compared with those achieved using other B-cell markers against CD19, CD20 and CD22. Although a small number of cases of nodular sclerosis and mixed cellularity subtype showed positivity for CD19, CD20 or CD22, no case showed any reactivity with antibodies against mb-1 or B29. This contrasted markedly with the cases of lymphocyte predominance where all seven cases expressed one or more of the B-cell antigens, with six cases being positive for mb-1. These results confirm previous studies that have suggested lymphocyte-predominance Hodgkin's disease is of B-cell origin and different from the other subtypes. However, they do not provide support for the thesis that these other subtypes may also have a B-cell origin, albeit with a different phenotype to lymphocyte predominance.

Antigens, CD↗
PubMed1993

High incidence of Epstein-Barr virus detection in Hodgkin's disease and absence of detection in anaplastic large-cell lymphoma in children.

By in situ hybridization with EBER oligonucleotides and immunohistochemistry with anti-latent membrane protein 1 (LMP1) antibody, we compared the detection rate of Epstein-Barr virus (EBV) in Hodgkin's disease and anaplastic large-cell lymphomas in children. Among the 13 cases of Hodgkin's disease tested, 7 (54%) were found to be EBV associated (EBER transcripts +, LMP1 +). None of the 11 cases of ALC lymphomas was found to contain EBV genomes or gene products. This may indicate that EBV is not a pathogenic agent in anaplastic large-cell lymphomas in children in comparison to Hodgkin's disease.

Adolescent↗
PubMed1993

Absence of Epstein-Barr virus carrying cells in synovial membranes and subcutaneous nodules of patients with rheumatoid arthritis.

OBJECTIVES: To determine whether the Epstein-Barr virus is present in synovial membranes and subcutaneous nodules of patients with rheumatoid arthritis. METHODS: A sensitive in situ hybridisation technique was applied to tissue sections of 11 synovial membranes and five rheumatoid nodules. RESULTS: Cells carrying the Epstein-Barr virus were not detected using EBER and BHLF1 oligonucleotides in the tissue samples investigated here. CONCLUSIONS: Although it has been suggested that the Epstein-Barr virus could play a part in the aetiology of rheumatoid arthritis, it was not detected in synovial membranes and subcutaneous lesions in this study.

Arthritis, Rheumatoid↗
PubMed1993

Relation of follicular dendritic reticulum cells to Reed-Sternberg cells of Hodgkin's disease with emphasis on the expression of CD21 antigen.

Based on observations of 66 cases, in which tissues were specially processed to optimize the simultaneous preservation of cell membrane antigens and morphology, we provide evidence in favor of a relationship between follicular dendritic reticulum cells (FDRC) and Reed-Sternberg (RS) cells of Hodgkin's disease (HD) other than the lymphocyte predominance subtype. RS cells were intimately related to the FDRC network (75% of cases), and the expression of CD21 antigen was frequent (41% of cases). Exclusive expression of CD21 antigen was found in 11 cases of HD, while the expression of other B-cell-associated markers (CD19, CD20, CD22) was both variable and inconsistent. The expression of T-cell antigens (CD3, CD4, CD8) was rare. Null phenotype of RS cells was observed in 27 of 66 cases (41%). Epstein-Barr virus (EBV) nucleic acids were found in 34 of 66 (51.5%) cases. Double labeling techniques showed the presence of EBV-positive RS cells within the FDRC network. A non-B-cell origin of RS cells was supported by the differential expression of EBV latent antigens in HD (latent membrane protein+, EB nuclear antigen 2-), which is unusual in EBV-driven lymphoblastoid cell lines and EBV-positive B-cell lymphomas. FDRC and RS cells are known to share morphological traits (binucleated cells), and both cell types possess Fc receptor for IgG. The hypothesis is further backed by the findings of CD15 antigen expression by occasional RS-like dysplastic FDRC in Castleman's disease (five cases), which is characterized by hyperplasia of FDRC. Whether FDRC might be the only cells involved in the conversion to RS cells by the loss or gain of antigens remains to be determined.

Antibodies↗
PubMed1993

Assessment of the methods for the detection of Epstein-Barr virus nucleic acids and related gene products in Hodgkin's disease.

BACKGROUND: Epstein-Barr virus (EBV) is present in the pathogenic cells of a significant number of cases of Hodgkin's disease, particularly of the mixed cellularity subtype. EBV remains latent and the incidence of detection rate of the genomes and gene products varies greatly with the methods employed. EXPERIMENTAL DESIGN: From a pool of 137 cases of Hodgkin's disease previously studied by cold in situ hybridization (ISH) for the presence or absence of EBV DNA and the immunohistochemical reactivity with anti-latent membrane protein 1 antibody, we selected 24 cases (12 EBV DNA-positive, 12 EBV DNA-negative) for Southern blotting, as well as for study with nonisotopic EBER and BHLF1 oligonucleotide probes and amplification of DNA by polymerase chain reaction. EBV positive cases were further tested with anti-ZEBRA (BZLF1) antibody. RESULTS: The EBV DNA detection rate was found to be lower with Southern blotting compared to ISH and IHC methods because 8 of the 12 EBV positive cases were positive with BamHI W probe and only 7 (of the 8) with XhoI 1.9 kb probe. These 7 cases contained monoclonal episomal circular EBV genomes. All EBV DNA-positive cases showed EBER gene transcription by ISH. EBER probes also reacted with small lymphocytes in all EBV DNA+ and 9 EBV DNA- cases. These EBER-positive small lymphocytes were detected neither by BamHI W DNA probe nor by immunohistochemical methods with anti-latent membrane protein 1 and anti-EBNA2 antibodies. Polymerase chain reaction produced a positive result in all EBV DNA+ cases and 2 (of the 9) EBV DNA- cases containing EBER+ small lymphocytes. This discrepancy was attributed to amplification of EBV in reactive lymphocytes. Anti-ZEBRA antibody was positive in 2 cases (one BHLF1+) suggesting infrequent viral replication and probable abortive lytic cycle. CONCLUSIONS: ISH and immunohistochemical methods are more sensitive than Southern blot for detecting EBV in Hodgkin and Reed-Sternberg cells of Hodgkin's disease. Polymerase chain reaction appears to be very sensitive but is less sensitive and specific (amplification of EBV DNA of non-neoplastic lymphocytes) than ISH with non-isotopic EBER oligoprobes, which often detects and localizes EBV in pathogenic cells even when they are in small numbers and also in a few small lymphocytes. In addition, this method offers the advantage of being applied to routinely processed tissue sections.

Antigens, Viral↗
PubMed1993

Spontaneous evolution of cytoplasmic lectin binding and nuclear size and deoxyribonucleic acid content in human colorectal cancers grafted onto nude mice.

BACKGROUND: The development of certain biologic characteristics in human colorectal tumor xenografted onto nude mice are described with respect to their precocious passages, i.e., passaging below 10 onto athymic mice. EXPERIMENTAL DESIGN: The biologic characteristic monitoring involved the determination of modifications occurring in cytoplasmic lectin binding and spontaneous development in nuclear size and DNA content. The lectin immunohistochemistry included the characterization of staining modifications in the glandular parts of the colorectal xenografts of wheat germ, Dolichos biflorus, peanut, Solanum tuberosum and Ulex europaeus I agglutinins. The nuclear modifications were monitored by means of the digital cell image analyses of Feulge-stained nuclei. RESULTS: The results show that although the xenografted human colorectal lines may be relatively stable according to their macroscopic growth over serial passaging, certain of their microscopic characteristics develop markedly. Three lectins, i.e., wheat germ agglutinin, Solanum tuberosum, and Ulex europaeus I, showed a glandular binding which remained relatively stable over serial passaging, whereas the peanut binding exhibited some variations and the DBA binding progressively disappeared. These cytoplasmic modifications occurring over time were less pronounced than those that occurred with respect to nuclear measurements, i.e., size and DNA content. CONCLUSIONS: Nuclear DNA content heterogeneity as revealed by DNA histogram typing rather than by DNA index assessments increased markedly in the colorectal xenografts over their serial passaging on nude mice.

Animals↗
PubMed1992

A novel human lymphoma cell line (Deglis) with dual B/T phenotype and gene rearrangements and containing Epstein-Barr virus genomes.

We report a new and apparently unique human lymphoma cell line termed Deglis. The line was established from a polymorphic centroblastic lymphoma. The cell line and its source carry a dual B-cell and T-cell phenotype and Epstein-Barr virus (EBV) genomes. Simultaneous expression of B-cell (CD19+, CD20+, CD23+, CD37+) and T-cell (CD2+, CD3+/-, CD7+, CD43+) antigens, activation antigens (CD30+, CDw70+) as well as CD68+, a macrophage-associated antigen, was observed on the cell line and its source. Genotypic studies of the cell line showed dual gene rearrangements. JH (on both primary tumor and the cell line) and C kappa were rearranged without expression of cytoplasmic or surface immunoglobulins. T-cell receptor-alpha (TCR-alpha) and TCR-beta genes were rearranged, but TCR-delta and TCR-gamma genes were in germline configuration. Apparently, functional transcripts of TCR-alpha and truncated transcripts for TCR-beta and TCR-delta were observed. EBV-encoded proteins (LMP and EBNA2) were expressed by the parent tumor and the cell line. Southern blot analysis showed the same clonal EBV genomes in the primary tumor and the cell line. Karyotypic analysis of the cell line showed several chromosomal abnormalities but normal chromosomal number. The characteristics of this cell line suggest that neoplastic transformation has occurred in a precursor cell broadly committed to lymphoid lineage. Further studies on this cell line may help resolve some issues in the physiopathology of lymphoid tumors.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1992

Spontaneous evolution of nuclear size and DNA content of non-small-cell-lung cancers grafted onto nude mice.

We monitored the biological evolution of four human non-small-cell lung cancers labeled KLX6, KLX7, KLX9, and KLX14 that had been grafted onto nude mice. This monitoring was carried out by means of digital cell image analysis which assessed morphometric (nuclear area, NA) and densitometric (nuclear DNA content, DI) features on Feulgen-stained nuclei from imprint smears. In each of the four models, the biological evolution of the NA and DI was characterized through their progression during serial passaging onto nude mice. The results show that of the four lung cancer models analyzed, one (KLX6) remained definitively stable with respect to its DNA content (DI assessments), while the other three, i.e., KLX7, KLX9, and KLX14, varied significantly. As assessed by the morphometric parameter, i.e., the NA, the four xenografted lines also varied significantly over serial passaging. In conclusion, we show that digital cell image analyses of Feulgen-stained cell nuclei including morphometric and densitometric parameters are a powerful tool for monitoring the biological evolution of human lung cancers grafted onto nude mice. We think therefore that the ploidy level of a tumor might be dependent upon its age and/or its related clinical stage.

Animals↗
PubMed1992

Production of a monoclonal antibody (IND.64) identifying a cell cycle-associated antigen using spleen cells from nude mice bearing Ichikawa tumour.

Using spleen cells from athymic nude mice grafted with Ichikawa tumour, we have generated the monoclonal antibody IND.64, which detects a proliferation-associated nuclear antigen. Immunoblotting analysis with IND.64 showed a double band with apparent molecular weights of 395 and 345 kD. In normal human tissues, the antigen detected by IND.64 was expressed only by the nuclei of proliferating cells, such as germinal centre cells of reactive lymph nodes, cortical thymocytes, the basal layer of the skin, and proliferative compartments of the stomach, small intestine, and colon. IND.64 did not react with cells known to be non-proliferative or to show only a low turnover, such as cells of the kidney, liver, smooth muscle, cardiac muscle, and brain. The expression of this antigen during the cell cycle was determined using two approaches: IND.64 immunostaining of synchronized adult bovine aortic endothelial cells and flow cytometric analysis of double-labelled PHA-stimulated peripheral mononuclear blood leucocytes with a DNA marker and IND.64. The antigen recognized by IND.64 was found to appear in the late G1 phase, and persisted in phases S, G2, and M, but was absent in the G0 and early G1 phases. IND.64 was further investigated in different tumour types to evaluate the correlation between the percentage of IND.64-positive cells (IND.64 index) and the histological grade. In non-Hodgkin's lymphomas, an excellent correlation was found between the percentage of IND.64-positive cells and the cytomorphological grade. In nodular sclerosis and mixed cellularity Hodgkin's disease, a high number of Reed-Sternberg cells were positive with IND.64. The non-lymphoid neoplasms investigated showed a variable percentage of positive cells. IND.64 appears to be a promising tissue marker to complement the evaluation of prognosis in human cancer.

Animals↗