Search PubMed⌕ Search

Biomedical subjects

G Delsol

Publications and source records attributed to G Delsol.

At least 163 records · Page 9Linked to original sources
PubMed1992

Immunobiochemical characterization of the antigen detected by monoclonal antibody IND.64. Evidence that IND.64 reacts with the cell proliferation associated nuclear antigen previously defined by Ki-67.

The immunohistochemical characteristics of the monoclonal antibody IND.64 are very similar to those of the monoclonal antibody Ki-67. The aim of this study was to further characterize this new antibody and to compare it with Ki-67 using immunobiochemical methods. Our results demonstrate that the similarity between the antibodies holds true even at the molecular level. Immunoblot analysis of IM-9-cell lysates with both antibodies showed a double band with apparent molecular weights of 395 kD and 345 kD, respectively. Competition ELISAs using a synthetic peptide derived from the thus far determined Ki-67 cDNA sequence as competitor, indicate that IND.64 may recognize the same epitope as Ki-67. The IND.64 epitope resides at least within a 20 amino acid sequence which also contains the Ki-67 epitope. Since IND.64 is of the IgG2b subclass, while Ki-67 is of the IgG1 subclass, the two antibodies may be useful for double immunostaining. In addition, IND.64 may help in determining the still unknown function of the antigen it recognizes.

Antibodies, Monoclonal↗
PubMed1992

Comparative quantitative study of Ki-67 antibody staining in 78 B and T cell malignant lymphoma (ML) using two image analyser systems.

Total Ki-67 stained area percentage was studied in 32 B and 46 T malignant lymphomas (ML) using two different image analyser systems (TAS, Leitz; SAMBA TM 2005, TITN) respectively. The total Ki-67 area percentage was highly correlated to the number of Ki-67 positive cellular profiles (B-ML, r = 0.93; T-ML, r = 0.88), indicating that area percentage is a reliable alternative method to the manual cell counting. Image analysis allows quicker measurements, appropriate to large and strictly lymphomatous regions. The cell image processor (SAMBA TM 2005, TITN) linked to a color video camera was more suitable for immunohistochemical sections and allowed more automated and faster measurements than the texture analyser (TAS, Leitz) linked with a black and white camera. Alkaline phosphatase technique with fast red as chromogen was more suitable for the detection of Ki-67 stained area by thresholding than peroxidase technique with aminoethylcarbazol or with diaminobenzidine as chromogens. Significant differences were found between low and high grade in B and T ML according to the Kiel classification (mean values +/- SD of 7.7 +/- 3.8% and 16.6 +/- 6.2% in B-ML and of 10.2 +/- 7.9% and 25.6 +/- 16.3% in T-ML respectively). In follicular B-ML, considering follicular areas only, values were comparable to high grade ML; angioimmunoblastic-lymphadenopathy-like (AILD-type) T-ML belonging to low grade ML showed similar values to pleomorphic T-ML with medium and/or large cells belonging to high grade ML.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkaline Phosphatase↗
PubMed1992

Hodgkin's disease and Epstein-Barr virus.

Seroepidemiological and molecular biological studies have established an association of Hodgkin's disease with Epstein-Barr virus (EBV). Recently, EBV genomes and gene products, most notably the latent membrane protein (LMP), have been detected in approximately 50% of the cases. The findings suggest that EBV may contribute to the pathoetiology of a sizable proportion of Hodgkin's disease cases.

Antigens, CD↗
PubMed1992

A multiparametric study of malignant lymphoma of mucosa associated lymphoid tissue (MALT).

A morphological, immunophenotypic and ultrastructural study, cell cycle estimation, DNA and cytogenetic analysis were performed in ten cases of B-MALT lymphomas. Five had low grade lymphoma and five had high grade. Low and high grade cases showed the same cells but in different percentages: These included centrocyte-like cells with occasional monocytoid cytoplasmic changes, and centroblast-like cells. However, in high grade cases more dysplastic and large cells were present. All cellular types showed an important development of rough endoplasmic reticulum. In all cases a large panel of monoclonal antibodies was employed to study the B-cell immunophenotype. Ki-67 positivity ranged from 5% to 30% in low-grade cases and from 50% to 70% in high-grade cases. Gene rearrangement analysis showed rearrangement with Jh probe and half of the cases were also rearranged with the Kde probe (Kappa constant chain gene). A rearrangement banding pattern with TCR genes was not present in any of the cases. Cytogenetic study showed complex alterations in high grade cases and a normal karyotype in low grade lymphomas. Only one case had rearrangement for the bcl-2 probe.

Female↗
PubMed1992

Correlation of the expression of Epstein-Barr virus latent membrane protein and in situ hybridization with biotinylated BamHI-W probes in Hodgkin's disease.

The detection of Epstein-Barr virus (EBV) nucleic acids by in situ hybridization (ISH) with biotinylated BamHI-W probes was correlated with the expressions of EBV latent membrane protein (LMP) and EB nuclear antigen 2 (EBNA2), in 107 cases of Hodgkin's disease (HD) of different immunomorphologic subtypes. Epstein-Barr virus nucleic acids were present and restricted to the pathogenic cells in 4 of 40 (10%) cases of nodular sclerosis (NS) and 33 of 55 (60%) cases of mixed cellularity (MC), but were undetectable in other subtypes. Of the 37 cases positive for EBV nucleic acids, 35 (95%) showed the expression of LMP. Epstein-Barr virus nucleic acids and LMP were restricted to Reed-Sternberg cells and variants. Only 1 case (MC) showed LMP expression in the absence of EBV detection. The correlation was strengthened by the finding of LMP expression at first diagnosis in 6/7 EBV positive cases at relapse (14-126 months) (5/5 EBV negative cases at relapse were LMP negative at first diagnosis). EBNA2 was absent in all 13 (NS, 2; MC, 11) EBV+ and LMP+ cases tested. Both LMP and EBNA2 were expressed in control EBV-positive tissues and cell lines. EBV serology in MC HD was indicative of latent EBV infection, but neither serology nor clinical parameters correlated with the presence or the absence of EBV, over a short-term follow-up (median, 20 months). The findings, although not proving EBV as the etiologic agent of HD, suggest that: 1) LMP expression alone may be adequate for identifying EBV-associated HD, 2) the MC subtype has a stronger relation with EBV presence, and 3) the regulation of EBV genes in HD is different from other EBV-associated disorders. The clinical implications still remain to be discovered.

Antigens, Viral↗
PubMed1992

Comparison of in situ hybridization using different nonisotopic probes for detection of Epstein-Barr virus in nasopharyngeal carcinoma and immunohistochemical correlation with anti-latent membrane protein antibody.

BACKGROUND: The detection of Epstein-Barr virus (EBV) in nasopharyngeal carcinoma (NPC) may be of diagnostic importance, particularly in cases from nonendemic areas. For cellular localization of viral genomes, cold in situ hybridization methods for the demonstration of EBV-associated NPC remain difficult and relatively insensitive for routinely processed tissues. EXPERIMENTAL DESIGN: The aim of the present study was to assess the importance of tissue processing and the hybridization targets to improve the sensitivity of the cold in situ hybridization method. In situ hybridization was performed in six cases of NPC using three biotinylated EBV cDNA probes (BamHI W/IR1, BamHI Y/EBNA2, XhoI/latent membrane protein) and two cocktails of EBER and BHLF1 oligonucleotides labeled with fluorescein isothiocyanate on routinely fixed and paraffin embedded sections. In two cases, in situ hybridization was also performed on specially processed (ModAMeX) sections. Immunohistochemistry was used to detect EBV-induced antigens using monoclonal antibodies against latent membrane protein, EBNA2 and ZEBRA (BZLF1). RESULTS: All cases showed EBV nucleic acids regardless of the tissue preparation with the three cDNA probes and on routinely processed sections with EBER oligonucleotides. By using cDNA probes, the best EBV DNA signal was obtained with BamHI W without heating of slides in tissue sections processed by ModAMeX, which probably gives rise to large amounts of single stranded DNAs. All cases positive with cDNA probes were found to be positive with EBER oligonucleotides and negative with BHLF1. However, on routinely processed paraffin sections, the signals with EBER oligonucleotides were stronger than with BamHI W cDNA probe. Dual labeling with in situ hybridization and immunohistochemistry showed that the hybridization signals were restricted to malignant epithelial cells. Latent membrane protein expression was detectable in four of six EBV nucleic acid-positive cases on both ModAMeX and routinely processed sections. The anti-EBNA2 and anti-ZEBRA antibodies were found to be negative on the two cases processed by ModAMeX. CONCLUSIONS: Cold in situ hybridization, in particular with EBER oligonucleotides, appears to be more reliable than immunohistochemistry with anti-latent membrane protein antibody to detect EBV in NPC in routine pathology. These findings confirm a distinctive phenotype (latent membrane protein +/-, EBNA2-, ZEBRA-) of EBV-positive NPC. The negative staining for BHLF1 oligonucleotides further supports the viral latency.

Antibodies, Monoclonal↗
PubMed1992

[Simultaneous detection by non-isotopic in situ hybridization of human papilloma viruses and Epstein-Barr virus during the lytic cycle in oral hairy leukoplakia lesions].

Oral hairy leukoplakia is almost only described in patients infected by the human immunodeficiency virus. Epstein-Barr virus, sometimes associated with human papillomavirus, is always involved in the occurrence of these lesions. We have investigated two cases of oral hairy leukoplakia with the goal of detecting EBV and HPV by using both in situ hybridization and immunohistochemistry. EBV genome was detected with biotinylated BamHI W cDNA probe in the two cases. Furthermore, EBV was found to be in lytic phase as demonstrated by the strong signal observed with FITC-labelled anti-sense BHLF1 oligonucleotide probes. This finding was further supported by the absence of labelling with EBV-latent-cycle markers such as EBER1/2 oligoprobes and anti-latent membrane protein 1 antibody. In addition, these two cases were positive for HPV genomes: 31-33-51 (n = 1) and 31-33-51 plus 6-11 (n = 1) as detected by in situ hybridization using different sets of biotinylated probes. The signal obtained with in situ hybridization (both HPV and EBV) was localized to the upper layers of epithelial cells. The mechanism of oral hairy leukoplakia remains still unknown, but this work emphasizes the value of in situ hybridization with nonisotopic probes in the detection of viral nucleic acids on routinely processed tissue sections. The fact that these lesions seem to precede the AIDS phase emphasizes the clinical implications of this diagnosis in HIV infected patients.

Adult↗
PubMed1991

Malignant histiocytosis X. A distinct clinicopathologic entity.

Histiocytosis X (HX) is characterized morphologically by a proliferation of Langerhans' cells (LC), and most often has an indolent, chronic course. To determine whether a distinct clinicopathologic entity of malignant histiocytosis X exists, the authors examined tissues from 31 patients with HX and divided them into four categories. Group A (19 patients) was characterized morphologically by benign-appearing LC and had an indolent course. The male:female (M:F) ratio was 10:9, and the mean age was 21 years (range, 2 months to 60 years). The immunophenotype of this group was S-100+, vimentin+, LN-2+, LN-3+, lysozyme-, LCA-, Leu-M1-. Group B (three patients) had benign-appearing LC, yet had an aggressive clinical course. All patients were male, with a mean age of 47 years (range, 3 years to 72 years). Organs involved included the liver, spleen, heart, thymus, lung, kidney, and pancreas. The immunophenotype was the same as for Group A. Group C (two patients) had atypical and malignant appearing LC, yet a relatively benign clinical course. The ages were four and 65 years, with one female and one male patient. In both patients, the cells were S-100+, vimentin+, LN-2+, LN-3+, and LCA-. Group D (seven patients) was characterized by atypical and malignant-appearing LC and an aggressive clinical course. The mean age was 25 years (range, congenital to 54 years) with one female and six male patients. Organs involved were the thymus, lungs, spleen, liver, kidney, brain, heart, pancreas, stomach, and muscle. Birbeck granules were found in two patients, and the one patient on which fresh tissue was available was CD1+. The typical immunophenotype was S-100+, vimentin+, LN-2+, LN-3+, Leu-M1-, lysozyme-. The results of our study indicate that (1) a distinct clinical entity of malignant HX, characterized morphologically by malignant-appearing LC and clinically by male predominance, atypical organ involvement, and an aggressive clinical course, does exist; and (2) the morphologic appearance of the LC is an imperfect predictor of the clinical severity of HX.

Adolescent↗
PubMed1991

Primary anterior mediastinal B-cell lymphoma. A clinicopathologic and immunohistochemical study of 16 cases.

Sixteen cases of primary anterior mediastinal B-cell lymphoma were characterized by morphologic, immunophenotypic, and clinical profiles. Twelve were men and four were women. The median age was 42 years. Virtually all tumors were of large cell type. Three main morphologic categories were identified, with one rare exception. In some tumors, the cells were compatible with centrocytes and centroblasts (four). Others had cells readily identifiable as centroblasts (six). Both these groups had a variable proportion of cells with multilobed nuclei. A third group was composed mainly of unclassifiable cells with multilobed nuclei (five). All had discernible sclerosis of varying intensity. A wider range of morphologic features and different sex distribution was noticed in comparison with previously reported clear cell features and younger women. The dominant phenotype of these B-cell lymphomas was CD19+, CD22+, CD37+, CD21-, CD30-, CD10-, CD5-, and Ig-negative. The finding of CD21-, Ig-negative phenotype, as observed by the authors and others, overlaps with some high-grade lymphomas of follicular center cell origin but is thought to bear similarity to a noncirculating population of thymic medullary B-cells. The tumors attained large size without peripheral dissemination and responded to chemotherapy as well as radiotherapy.

Adult↗
PubMed1991

Detection of Epstein-Barr virus messenger RNA in Reed-Sternberg cells of Hodgkin's disease by in situ hybridization with biotinylated probes on specially processed modified acetone methyl benzoate xylene (ModAMeX) sections.

Microscopic intracellular detection of Epstein-Barr virus (EBV) messenger RNA in Reed-Sternberg cells of Hodgkin's disease (HD) was possible by in situ hybridization, in tissue sections prepared by a method termed modified acetone methyl benzoate xylene (ModAMeX). The ModAMeX method was initially developed for simultaneous optimal preservation of leucocyte differentiation antigens and morphology. Two biotinylated DNA probes, corresponding to the same BamHI-W (internal repeat) of the EBV genome were used. EBV mRNA was detected in neoplastic cells in 16 of 54 (30%) lymph node biopsy specimens from usual subtypes of HD (lymphocyte predominance, 0/5; nodular sclerosis, 4/22; mixed cellularity, 12/26; unclassified, 0/1). EBV mRNA was also detected in the lymph node biopsy of 1 additional human immunodeficiency virus (HIV)-related case of HD (mixed cellularity) and in 2 of 4 cases of B-cell lymphomas occurring in patients with acquired immunodeficiency syndrome (AIDS). In other non-Hodgkin's lymphomas, EBV mRNA was detected in only 1 of 41 cases. Cases of HD positive for EBV mRNA were immunostained by CD30 and CD15 antibodies. The hybridization signals were exclusively restricted to Reed-Sternberg cells and variants. When analyzed retrospectively, no statistically significant correlation emerged between hybridization findings, EBV serology, or disease outcome over the 3 years of the availability of ModAMeX technique. The findings support the contention of a direct role of EBV in the pathogenesis of HD, at least in some cases.

Adult↗
PubMed1991

Expression of P-glycoprotein restricted to normal cells in neuroblastoma biopsies.

Immunohistological detection of P-glycoprotein (P-gp) with monoclonal antibody C219 was performed on serial sections of 37 neuroblastoma specimens representative of the different forms of the disease, from stage 1 ganglioneuroma to stage 4 neuroblastoma. Malignant cells, irrespective of their degree of maturation varying from neuroblasts to ganglion cells, were negative on all specimens. The expression of P-glycoprotein was detected in nine specimens, but it was restricted to normal cells within the tumour. In four specimens, C219 reacted with normal infiltrating cells in the stroma (i.e. monocytes, histiocytes or fibroblasts) representing 5 to 10% of the total population within the section; in three specimens, the residual adrenal gland was strongly positive, and in two ganglioneuromas, a weak reactivity of C219 was observed on a few satellite cells and schwann cells. Three of 15 biopsies obtained at diagnosis contained normal P-gp positive cells: two were classified as stage 1 ganglioneuromas; one was a typical stage 4 composite tumours with positive histiocytes and fibroblasts in the well-differentiated counterpart. Six of 22 biopsies obtained after patients had received our current protocol of chemotherapy contained normal P-gp positive cells: five were partially differentiated and necrotic under the effect of chemotherapy; only one positive specimen was classified as undifferentiated neuroblastoma. Among negative specimens from previously treated patients, one was obtained from a patient in relapse after high-dose chemotherapy and ABMT, two were obtained from patients who had not responded to induction therapy, and six from patients in partial remission after induction therapy. The clinical evolution was very similar in both groups of patients with P-gp negative or positive biopsies. These findings suggest that the quantitative assessment of MDR RNA by northern blotting on fresh homogenates is likely to overestimate its expression on neuroblastoma cells, and that the mechanism of chemoresistance in widespread neuroblastoma is less likely to be associated with P-gp expression.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1991

Antibody BNH9 detects red blood cell-related antigens on anaplastic large cell (CD30+) lymphomas.

Two new monoclonal antibodies--BNH9 and BNF13--were generated by using a human lung adenocarcinoma cell line and standard hybridoma techniques. Both were found to react with epithelial and endothelial cells in routinely fixed and embedded tissues. Unexpected membrane labelling of some large cell lymphomas while non-reacting with normal lymphoid cells, prompted further characterisation. The antibodies were found to recognise red blood cell-related oligosaccharide antigens. The specificities were directed towards H and Y determinants. A distinctive pattern of reactivity was found for BNH9 in studying 480 cases of various lymphoid neoplasms. Strong expression of H and/or Y antigens was observed in 65/127 (51%) cases of anaplastic large cell(ALC) (CD30+) lymphomas, which are also known to co-express epithelial membrane antigen (EMA) frequently. Only a minority (less than 6%) of other non-Hodgkin's lymphomas (NHL) (CD30-,EMA-; 208 cases) and Hodgkin's disease (HD) (CD30+, EMA-; 126 cases) were positive. Expression of H and Y antigens was inducible on normal lymphocytes by mitogenic stimulation and by Epstein-Barr virus infection. The data suggest remarkable biological differences of ALC lymphomas within NHL and from HD.

Antibodies, Monoclonal↗
PubMed1991

Large B-cell lymphoma rich in T-cells and simulating Hodgkin's disease.

Unusual clinicopathological features drew our attention to nine of 208 cases diagnosed as Hodgkin's disease. Lymph node biopsy specimens in these cases were immunostained with monoclonal antibodies against B-cell, T-cell and Reed-Sternberg cell associated antigens and epithelial membrane antigen (EMA). Reed-Sternberg-like and other atypical large cells were dispersed in a diffuse, small lymphocyte-rich background, consistent more often with the initial diagnosis of diffuse, lymphocyte predominance Hodgkin's disease. The clinical stage in these cases was unusually advanced (stages III and IV). Splenomegaly was a common feature (six of nine cases), the male to female ratio was 7:2 and the median age was 55 years (range 25-77). Response to recognized regimes for Hodgkin's disease treatment was poor in most cases, and three patients died early of their disease. Large cells were B-lymphocytes expressing EMA--an immunophenotype similar to nodular, lymphocyte predominance Hodgkin's disease. Reed-Sternberg cell and T-cell associated antigens were absent on large cells. Mature T-cells, with nuclear irregularities in some instances, predominated in the background. A more appropriate diagnostic category is, therefore, T-cell-rich B-cell lymphoma. The cases represent a 4-5% erroneous diagnosis of Hodgkin's disease and further suggest that there is a need for revision of criteria for the diagnosis of the diffuse, lymphocyte predominance variant.

Adult↗
PubMed1991

Hairy cell transformation of a B-cell chronic lymphocytic leukemia: a morphological, cytochemical, phenotypic and molecular study.

The normal counterparts of the B cells found in hairy cell leukemia (HCL) are not known. We report here a detailed morphological, cytochemical, immunological and molecular analysis of a patient with B-cell chronic lymphocytic leukemia (B-CLL) who later in the course of his disease developed hairy cell leukemia. We speculate that hairy cell transformation of B-CLL might be related to an in vivo protein kinase C mediated cellular activation of B-CLL cells.

Blotting, Southern↗