Search PubMed⌕ Search

Biomedical subjects

G Delsol

Publications and source records attributed to G Delsol.

At least 181 records · Page 10Linked to original sources

Production of a monoclonal antibody (2B44) reactive on a shared epitope on dendritic reticulum cells, smooth muscle cells of vessels and Reed-Sternberg cells.

Lymph node cells from a patient with Hodgkin's disease (HD) were cultured without Epstein-Barr virus (EBV) or leukine adjuvant. A cell line (719-AB) emerged from the culture after four weeks. The cell line express CD20 (79%), CD 21 (30%), CD30 (63%), CD 35 (61%) antigens and weakly CD25 (19%). using Southern Blot technique, the existence of specific EBV DNA and polyclonal immunoglobulin genes rearrangement were observed in the cell line. In order to obtain a monoclonal antibodies (MoAb), mice Balb/C were immunized with this cell line. The splenic cells suspension of immunized animals were fused with the mouse myeloma NS1. Antibody IgM kappa from secreting clones 2B44 was studied using both indirect immunofluorescence with labeled anti-mouse immunoglobulin and immunohistochemistry based on alkaline phosphatase/antiphosphatase complex (APAAP) and ModAMeX technique on a panel of normal or pathological cells. Normal peripheral lymphocytes, monocytes, polymorphonuclear cells, and erythrocytes, did not react. The MoAb 2B44 recognized the dendritic reticulum cells and the smooth muscle cells of vessels on frozen section and paraffin section from HD or reactive lymph nodes. On specially processed paraffin sections (ModAMeX) Reed-Sternberg cells (RSC) were reactive with 2B44 MoAb (in 2 cases out of 5 tested). The molecular weight of the antigen recognized by 2B44 MoAb is of 37 kd. The description of a new epitope shared by different histological components might be of interest for defining a new cluster and better understanding the nature of RSC.

Antibodies, Monoclonal↗

Peripheral T-cell lymphoma associated with hemophagocytic syndrome.

Nine patients with an acute disease characterized by high fever, loss of weight, prominent hepatosplenomegaly, slight or no lymphadenopathy, abnormal liver function tests, and profound pancytopenia are reported. In all cases, the disease presented in the absence of any pre-existing disease or immunosuppressive therapy. In seven of the nine patients, survival was very short (mean = 7 weeks). Two patients are still alive: one had a relapse 24 months after the initial diagnosis, while the other is in complete remission. The main pathological feature was the infiltration of the marrow, spleen and liver by neoplastic T cells, accompanied by an exuberant hyperplasia of benign-looking, hemophagocytizing histiocytes. The term "peripheral T-cell lymphoma with hemophagocytic syndrome" is proposed for this condition. Retrospective analysis of stored paraffin material (1949 to 1965) from the Radcliffe Infirmary files suggests that at least some of the cases designated as "histiocytic medullary reticulosis" by Scott and Robb-Smith were examples of the syndrome herein described.

Autopsy↗

Malignant lymphomas of true histiocytic origin. A clinical, histological, immunophenotypic and genotypic study.

The clinical, histological, immunophenotypic and genotypic properties of four cases of lymphoma of true histiocytic origin are described. The cases were identified by typing 925 non-Hodgkin's lymphomas by immunophenotypic and/or genotypic techniques, and they all presented with skin lesions. The histological and immunophenotypic examination showed dense, diffuse infiltrates of markedly pleomorphic mononuclear cells that were positive for macrophage-associated markers, and negative for B-cell, T-cell and myeloid cell-associated antigens. Staining for Ki-1 and epithelial membrane antigen was also negative. Gene rearrangements studies were performed in three cases, and all of these showed germline configuration of both T-cell receptor and immunoglobulin genes. In all cases, the clinical course was aggressive with rapid and widespread dissemination to internal organs, poor response to conventional chemotherapy, and short survival times (0.5 to 14 months). This suggests that although true histiocytic tumours are very rare, their recognition may be important for clinical and/or prognostic reasons.

Adult↗

Variable expression of leucocyte-common (CD45) antigen in CD30 (Ki1)-positive anaplastic large-cell lymphoma: implications for the differential diagnosis between lymphoid and nonlymphoid malignancies.

Monoclonal antibodies (mAbs) directed against the leucocyte common (CD45) antigen have been proposed as a useful tool for the differential diagnosis between malignant lymphomas (CD45+) and poorly differentiated nonhemopoietic tumors (CD45-). Thanks to the availability of mAbs directed against fixative-resistant epitopes of the CD45 molecule, this distinction can now easily be made even in routinely processed tissues. However, a small percentage of morphologically poorly defined neoplasms are difficult to diagnose even with the help of immunohistochemistry. The investigators report that 63 out of 165 anaplastic large-cell (ALC) lymphomas did not show any reactivity for the CD45 antigen in paraffin sections. In routine biopsies, the lymphomatous nature of these cases, most of which had been sent for consultation, could be always unequivocally established by demonstrating negativity for cytokeratins (mAb KL1) and clear dot-like and/or surface reactivity with the Ber-H2 mAb, which is directed against a fixative-resistant epitope of the lymphoid cell activation antigen CD30. Strikingly, 54% of the CD45-cases reacted with mAbs directed against fixative-resistant epitopes of the T cell-restricted CD45RO antigen (mAb UCHL1) or the B-restricted molecules CD45RA (mAb 4KB5) and L26 (unclustered). In order to avoid confusion of ALC lymphomas with anaplastic nonlymphoid tumors, pathologists must be aware of the existence of CD30+/CD45- ALC lymphomas, as they can mimic the above-mentioned malignancies both morphologically (due to the sinusoidal growth pattern) and phenotypically (due to the expression of EMA). The investigators conclude that the combined use of mAbs directed against fixative-resistant epitopes of the CD30, CD45RO, CD45RA, and L26 antigens and cytokeratins is essential for the correct diagnosis and treatment of these equivocal cases.

Antibodies, Monoclonal↗

Further phenotypic evidence that nodular, lymphocyte-predominant Hodgkin's disease is a large B-cell lymphoma in evolution.

Five cases of nodular, lymphocyte predominant Hodgkin's disease (nLP HD), in which an association with (n = 3) and transformation to (n = 2) large cell lymphoma (LCL) were found, were studied with monoclonal antibodies against B-, T-, and Reed-Sternberg (R-S) cell-associated antigens and epithelial membrane antigen (EMA) on paraffin sections. Both lymphocytic (L) and histiocytic (H) cells of nLP HD and lymphoma cells of LCL expressed multiple B-cell-associated antigens (detected by LN-1/CDw75, L26, MB2, DBB.42, DBA.44, DND.53, DNA.7 antibodies) but did not react with antibodies against T-cell-associated (MT1, UCHL1/CD45RO) (one exception for CD45RO in LCL) and R-S cell-associated (Leu-M1/CD15, Ber-H2/CD30) antigens. EMA was expressed by L and H cells in all cases and conserved in LCL cells, emphasizing the frequent expression of EMA by the diagnostic cells of nLP HD. An antibody (BNH9) against blood group-related antigens (H and Y oligosaccharide antigens) that does not normally react with lymphoid cells was found to be reactive with few L and H cells in two of five and most LCL cells in four of five cases. The finding might be indicative of abnormal activation of lymphoid cells. The data reinforce current implications that nLP HD is a B-cell malignancy in evolution and that it is not truly representative of Hodgkin's disease in terms of biological and clinical behavior.

Adult↗

Lymphohistiocytic T-cell lymphoma (anaplastic large cell lymphoma CD30+/Ki-1 + with a high content of reactive histiocytes).

We describe 13 cases of a peculiar lymphoid tumour containing very large numbers of reactive histiocytes. The tumours occurred in young patients (mean age 14.8 y) who presented with systemic symptoms and superficial lymphadenopathy. Microscopic examination revealed a diffuse effacement of lymph node structure due to the presence of histiocytes intermingled with a variable number of anaplastic large lymphoid cells. The latter, in some cases, were isolated, while in others they were arranged in clusters or were diffusely present in residual sinuses. The large anaplastic cells expressed the activation markers CD30 (Ki-1), CD25 (interleukin-2 receptor), CD70 (Ki-24) and Ki-27, as well as varying combinations of T-associated molecules. The histiocytes expressed lysozyme and the CD11b (C3bi-R), CD11c (p150, 95) CD14, CD68 (KPI) and Ber-Mac3 antigens. Double staining with the antibody Ki-67 demonstrated that the proliferating components were the CD30-positive cells and not the histiocytes. T-cell receptor beta gene rearrangements were shown in three cases tested. The patients responded well to aggressive chemotherapy and nine are still alive, eight in complete remission. It is suggested that the tumour represents a well-defined clinico-pathological entity originating from activated T-lymphocytes.

Adolescent↗

[Cells of the phenotype HNK-1 + (CD 57 +) in reactive adenopathies, lymphomas and Hodgkin's disease].

The number and distribution of Leu-7 + cells, a subset of Natural Killer cells clustered as CD 57 + cells, were studied with an immunoperoxidase technique on reactive lymph nodes (n = 13), malignant lymphomas (n = 60) and Hodgkin's disease (n = 22). Results of paraffin-section immunocytochemistry were compared with those obtained of frozen sections of the same tissues. CD 57 + cells are small lymphocytes mainly located in the germinal centers of reactive lymph nodes and in their malignant counterpart, i.e. the follicular lymphomas. The paragranuloma of Hodgkin's disease, type I nodular, contained high numbers of CD 57+ cells. Nine cases of CD 57+ lymphomas are reported, which were of high grade of malignancy. Their histological subtypes were anaplastic (3 cases) immunoblastic (2 cases), pleomorphic medium and large cell (3 cases), unclassifiable (1 case). Their diverse T-cell (4 cases) or B-cell (2 cases) origin and the various expression of epithelial membrane antigen (EMA) or Kil/Ber-H2 (CD 30) suggest an aberrant CD 57+ phenotype of a subset of large cell lymphomas.

Antigens, Differentiation↗

Immunohistochemical detection of multidrug resistance associated P-glycoprotein in stromal cells of malignant lymphomas.

We examined the distribution of the P-glycoprotein by immunohistochemistry in 25 malignant lymphomas (15 CHOP-derived regimen resistant non-Hodgkin's lymphomas and 10 Hodgkin's diseases). The study was performed on both cryostat and ModAMeX sections; the latter method preserves fixation-sensitive antigens and allows a more precise morphologic identification of neoplastic and non-neoplastic cell populations in contrast to cryostat sections. In both non-Hodgkin's lymphomas and Hodgkin's diseases, cells that were stained on cryostat sections were identified as macrophages and endothelial cells and not neoplastic lymphoid cells, by the ModAMeX technique. These findings suggest that the quantitative assessment of the multidrug resistance gene RNA by Northern blotting performed on fresh homogenates may overestimate the RNA content of neoplastic cells in a number of lymphoid tumors. In addition, the mechanism of chemoresistance in non-Hodgin's lymphomas is less likely to be associated with the P-glycoprotein expression.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

[T lymphocyte populations of the intestinal mucosa in celiac disease in children. Immunohistochemical study].

In order to study the distribution of lymphocyte subpopulations in a pathologic intestinal mucosa, the authors, instead of using the classic method by counting the number of lymphocytes, present an original method permitting the exploitation of quantified data from labelled surface cells by texture analyser coupled with a computerized system. We investigated 25 children presenting with chronic diarrhea and villous atrophy and 5 control subjects. Fifteen of the 25 children had celiac disease (10 active with total villous atrophy and 5, celiac disease in remission with healing mucosa), 5 cow's milk protein intolerance with total or partial villous atrophy and 5, chronic diarrhea with partial villous atrophy. Immunohistochemical study with monoclonal antibodies was carried out on frozen sections using a three-step immunoperoxidase technique. Compared with the 5 controls, patients with food intolerance (celiac disease and cow's milk protein intolerance) showed a significant increase of T suppressor lymphocytes (p less than 0.01 and p less than 0.05) in the epithelium, whereas there were more T helper lymphocytes in the lamina propria (p less than 0.05 and p less than 0.01). Non-treated celiac disease was distinguished from treated celiac disease by a marked increase in intra-epithelial T cytotoxic-suppressors. These results suggest that T cytotoxic-suppressors may be the mediators of the lesions observed in celiac disease.

Adolescent↗

Immunohistochemical profile of cutaneous B-cell lymphoma on cryostat and paraffin sections.

Thirty cases of primary (23 cases) and secondary (seven cases) cutaneous B-cell lymphoma (CBCL) were studied by immunohistochemistry using a selected monoclonal antibody (MoAb) panel on both cryostat and paraffin sections. On cryostat sections all CBCL so tested were positive for surface membrane immunoglobulins (IgMk most often) and B-cell antigens (CD22+, CD37+) with a variable T-cell-reactive component identified by MoAbs against T-cell antigens (CD2, CD3, CD4, CD5, CD8). CD4-positive stromal T-cells were usually more numerous than CD8-positive cells. A strong (50-75% of total cells) stromal T-cell (CD2+, CD3+) reaction was found in centroblastic-centrocytic lymphoma. Small numbers of CD1+ Langerhans cells were found in most cases, but they were present in large numbers in follicular lymphoma. On paraffin sections, a combination of MoAbs against B-associated antigens (LN-1, MB2) identified B-cell lineage in virtually all cases of CBCL. CBCL was negative for MoAbs against T-associated antigens (MT1, UCHL1) with rare exceptions (two cases). However, MT1 and UCHL1 combined identified the T-cell nature of all cases of nonepidermotropic, nonmycosis T-cell lymphoma, which were initially predictive of B-lineage by histologic pattern.

Adult↗

Immunohistochemical demonstration of leucocyte differentiation antigens on paraffin sections using a modified AMeX (ModAMeX) method.

The AMeX method (cold Acetone fixation with subsequent Methyl benzoate and Xylene treatment and routine paraffin embedding) has been recently revived for simultaneous preservation of morphology of cells and their antigens. We propose a modification of this method (ModAMeX), with the use of proteolytic enzyme inhibitors and low temperature paraffin wax embedding, which results in better preservation of a large number of leucocyte differentiation antigens and diagnostic morphologic detail. T-cell antigens (CD1, CD2, CD3, CD7 & CD8), B-cell antigens (CD22), macrophage associated antigens (CD11c, CD14 and others), activation antigens (CD25 and others), as well as some other antigens of diagnostic interest (CD10) were found to be preserved with a staining intensity equal to that of sections of fresh frozen tissue. Although the staining intensity of other T-cell antigens (CD4 & CD5), B-cell antigens (CD19, CD21 & CD37), activation antigens (Ki-1) and nuclear proliferation antigen (Ki-67) was slightly weaker as compared with frozen sections, this could be corrected by increasing the monoclonal antibody concentration. Staining for heavy and light chains of immunoglobulins was minor, sometimes compromised due to persistence of background staining as a result of extracellular immunoglobulins. The ModAMeX method has the advantages of simplicity, low cost and the possibility of exchange of tissue material between laboratories.

Acetone↗

Immunohistochemical detection of post-therapy residual testicular lymphoblasts in childhood acute lymphoblastic leukemia (ALL).

The aim of this study was to evaluate the diagnostic value of immunohistochemistry with monoclonal antibodies (MoAbs) in detecting residual blast cells in testicular biopsies from children with acute lymphoblastic leukemia (ALL). In a prospective study of 26 patients, testicular biopsies were performed after completion of therapy, and the average follow-up after biopsies was 29 months. After immunostaining, seven patients with negative biopsies on routine histology showed scattered, strongly calla-positive cells as well as cells reacting with anti-B (CD22) MoAb. Among these seven patients with residual blast cells, four had relapsed either in testes (n = 1), bone marrow and testes (n = 1), or in the bone marrow (n = 2). In contrast, among the 15 patients without residual blast cells, all but 1 remained in complete remission. In four other cases no definite conclusion was possible after immunohistochemical study. Four testicular biopsies from patients with occult infiltration were used as positive controls. Negative controls consisted of testicular biopsies from children with testicular ectopia and postmortem testicular tissue specimens. Results suggest that the risk of relapse is significantly higher in patients with positive immunohistochemical findings indicating persistent residual blast cells. However, the predictive value of these findings requires confirmation on a larger number of cases to have therapeutic implications.

Adolescent↗

The spontaneous development of immune complex type glomerular lesions in outbred mice is dependent on environmental factors and sex.

To investigate the role of environmental factors in the spontaneous development of immune complex glomerulonephritis in the mouse, follow-up studies of various immunological parameters and of kidney lesions have been done in male and female outbred OF1 mice housed from birth to four months of age in two different conditions: (a) in a conventional animal house; (b) in a "controlled" animal house designed for long-term studies on nude mice. Female mice housed under conventional conditions develop mild to intense glomerular lesions with granular deposits of immunoglobulins and C3 after two months of age. The appearance of these lesions is correlated with a sharp increase of various IgG subclasses levels at two months of age. Female mice housed under "controlled" conditions do not show such an increase and have only scarce to mild lesions until four months of age. In male mice, similar observations are done but the differences in immunological parameters and in histopathological findings between the two groups of mice according to the housing conditions are less noticeable. The environmental factors which are involved in the development of these immune mediated lesions are not known; it is hypothetized that infectious agents play a role. This study emphasizes the importance of housing conditions and of sex in immunopathological investigations in the mouse and the possible bias these conditions may introduce, in some experiments.

Animals↗

[Immunochemical diagnosis of hepatic localizations in malignant lymphoid hematologic diseases. Study of 80 cases].

The diagnostic value of immunohistochemistry using monoclonal antibodies was assessed in 100 liver biopsy specimens. The majority of these cases were hepatic localizations of lymphoid malignancies. Ten normal and reactive inflammatory liver biopsies were used as controls. Some monoclonal antibodies directed against leukocyte antigens revealed unexpected reactivities with normal liver structures: biliary tract (anti-CD10, anti-B MB2) and hepatocytes (anti-B LN1). In 12/17 cases of hepatic involvement by large cell malignancy, immunohistochemistry allowed the diagnosis of non Hodgkin's lymphoma (NHL); the remaining 5 cases were metastatic undifferentiated carcinoma. It was difficult to differentiate small cell liver NHL from reactive inflammatory infiltration. New anti-B (MB1, MB2, 4KB5, LN1 and LN2) and anti-T (MT1 and UCHL1) monoclonal antibodies suitable for use on paraffin sections were of value to phenotype NHL when only fixed material was available. But, information was too limited to distinguish malignant from reactive infiltrates. Immunohistochemistry on frozen sections was often necessary to diagnose inflammatory infiltrates and to phenotype NHL. Most NHL were of B cell origin (11/13 cases) and showed monotypic surface immunoglobulins as well as B cell-associated antigens (CD22+). The expression of the T CD5 antigen by B-cell NHL may have some diagnostic value. When monotypic surface immunoglobulins could not be demonstrated (due to background staining) the expression of this antigen by B lymphocytes was considered to be highly indicative of their neoplastic nature. Hairy cell leukemia exhibited a pathognomonic phenotype on frozen sections (CD11c+, CD22+, CD25+). T NHL were rare (2 cases) and difficult to diagnose due to the lack of clonal markers. The diagnosis of Hodgkin's disease in liver (15/20 cases) was facilitated by using paraffin sections of both monoclonal antibodies anti-CD15 (Leu M1) and anti-CD30 (Ber-H2) which detect fixation-resistant antigens expressed by Sternberg cells.

Antibodies, Monoclonal↗

[Experimental atherogenesis: early wall changes in the cynomolgus monkey].

The early parietal changes in atherogenesis are characterized by: Increase of endothelial permeability with proteoglycans and L.D.L. storage. Lysis of internal elastic lamellae. Penetration into sub-endothelial space of monocytes macrophages and transformation into foam cells. Parietal fibrosis and proliferating smooth muscle cells play a role in the extension of lipid deposit.

Animals↗