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D Y Mason

Publications and source records attributed to D Y Mason.

At least 199 records · Page 11Linked to original sources
PubMed1987

The role of immunocytochemistry in diagnostic pathology.

This review suggests that immunocytochemistry in diagnostic pathology can be performed using relatively small panels of antibodies and that it should be reserved for situations in which, for one reason or another, the pathologist cannot exert his or her conventional diagnostic skills. Examples include the diagnosis of tumours the true nature of which is uncertain because of anaplasia or poor morphological preservation; the demonstration of small numbers of cells which are otherwise too rare to be recognised in conventionally stained preparations; and the immunophenotyping of non-Hodgkin's lymphomas. Recently progress has been made in the context of non-Hodgkin's lymphomas by the development of monoclonal antibodies that detect T and B cell associated markers in paraffin wax sections. Most of these reagents, however, recognise either lineage associated (but not lineage specific) variants of the leucocyte common antigen CD45, or antigens that are poorly characterised. A recent promising development has therefore been the demonstration that polyclonal antisera raised against the CD3/T3 T cell specific marker (purified by affinity chromatography) are suitable for staining T cells in paraffin sections. This approach will hopefully enable antibodies to be produced which react with other well defined white cell associated markers in routine biopsy material.

Antibodies, Monoclonal↗
PubMed1987

Value of monoclonal anti-CD22 (p135) antibodies for the detection of normal and neoplastic B lymphoid cells.

Two monoclonal antibodies (To15 and 4KB128) specific for the B cell-associated CD22 antigen (135,000 mol wt) are described. On immunoenzymatic analysis of cryostat tissue sections, these antibodies strongly label both mantle zone and germinal center B lymphoid cells in secondary lymphoid follicles (and also scattered extrafollicular lymphoid cells) but are unreactive with other cell types (with the exception of weak reactivity with some epithelioid histiocytes). These reactions differ from those of monoclonal antibodies B1 and B2 (anti-CD20 and CD21) but are similar to those of the pan-B antibody B4 (anti-CD19). One of the anti-CD22 antibodies (To15) has been tested extensively by immunoenzymatic labeling on greater than 350 neoplastic lymphoid and hematological samples. The CD22 antigen was found in tissue sections in most B cell-derived neoplasms, the major exceptions being myeloma (all cases negative) and a small proportion of high-grade lymphoma (6% of cases negative). In cell smears, the antigen could be found on neoplastic cells in most B cell lymphoproliferative disorders, including common acute lymphoblastic leukemia (ALL) (90% positive) and B cell chronic lymphocytic leukemia (CLL) (89% positive). We conclude that anti-CD22 antibodies are of value for identification of human B cell lymphoproliferative disorders (especially when used in conjunction with anti-CD19 antibodies). Previous reports that the CD22 antigen is absent from many B cell neoplasms are probably due to its being expressed within the cytoplasm of immature B cells rather than on their surface.

Antibodies, Monoclonal↗
PubMed1987

Immunophenotyping of non-Hodgkin's lymphomas using a panel of antibodies on paraffin-embedded tissues.

The use of monoclonal and polyclonal antibodies for the immunophenotyping of non-Hodgkin's lymphomas in paraffin-embedded tissue has been limited by the fact that most antigens on lymphoid cells are denatured by histologic fixation, dehydration, and embedment. In this article the authors have analyzed a small panel of antibodies which represent exceptions to this rule, in that they identify denaturation-resistant determinants on leukocyte antigens in paraffin-embedded tissue. Monoclonal antibodies L26 [corrected] and 4KB5 label preferentially B cells, monoclonal antibody UCHL1 stains predominantly T cells, and monoclonal antibody MAC 387 reacts with granulocytes and some macrophages. A polyclonal antiserum raised against purified CD3 (T3) antigen, a T-cell-specific molecule, was also employed. This antibody panel was used to immunophenotype routinely processed tissue biopsy specimens from 61 non-Hodgkin's lymphomas (all of which had been previously phenotyped in cryostat sections). The lineage of the neoplastic cells was correctly identified in 32 of 34 (94%) cases of B-cell lymphoma, in 19 of 19 (100%) cases of T-cell neoplasm, and in 2 of 4 (50%) cases of histiocytic malignancy. It is concluded that this combination of antibodies is helpful in immunophenotyping non-Hodgkin's lymphomas when only paraffin-embedded tissue sections are available, although additional reagents of higher specificity are required to improve the identification of lymphomas.

Antibodies, Monoclonal↗
PubMed1986

APAAP labelling of blood and bone-marrow samples for phenotyping leukaemia.

The reliability of labelling routinely prepared air-dried peripheral-blood and bone-marrow smears with the alkaline-phosphatase/anti-alkaline-phosphatase (APAAP) method for phenotyping leukaemias was evaluated in 259 cases of haematological malignancy. All the cellular markers currently used in leukaemia diagnosis could be detected with this technique. Since the technique can be used on blood and marrow smears even after storage or postal transport, it is suggested that APAAP labelling should become the method of choice for immunophenotyping neoplastic samples in many haematology laboratories not equipped with specialised immunological diagnostic facilities. The method should also be valuable for epidemiological studies of leukaemia.

Acute Disease↗
PubMed1986

Osteoclasts contain macrophage and megakaryocyte antigens.

The origin and mechanism of formation of the osteoclast remains controversial. Although it is known to be derived from a circulating mononuclear percursor, the identity of this cell is unknown. Using a panel of monoclonal antibodies raised against macrophage and other marrow-derived cells, we determined the immunocytochemical staining of human osteoclasts in both fetal bone metaphyseal imprints and frozen sections. Osteoclasts and marrow mononuclear cells were stained by three broad spectrum antimacrophage antibodies, EBM-11, Y182a and BM2. T310, an antibody which stains macrophages and T helper cells, and C17, an antimegakaryocyte antibody, also stained osteoclasts. EBM-11, Y182a and BM2 also stained megakaryocytes in bone imprints as well as normal bone marrow smears. The presence of macrophage-associated antigens in osteoclasts, megakaryocytes and bone marrow mononuclear cells indicates that they are phenotypically similar to macrophages.

Antibodies, Monoclonal↗
PubMed1986

T-cell growth factor receptor (Tac-antigen) expression in cutaneous lymphoid infiltrates.

A total of ninety-four biopsies from normal skin, benign dermatoses, and lesions of human T cell lymphotropic virus type I (HTLV-I)-positive and -negative cutaneous T cell disorders have been examined immunohistologically for reactivity with anti-Tac (monoclonal anti-T cell growth factor receptor). Tac-positive T cells were plentiful in approximately half the specimens, and they were equally frequent in benign and malignant disorders and in HTLV-I-positive and -negative cutaneous T cell disorders. Furthermore, in diseased skin, reactivity with anti-Tac was not confined to T lymphocytes, since it was also a property of dermal macrophages and Langerhans cells, as shown by examination of serial and/or double-stained sections. Comparison with other markers linked to T cell activation and proliferation (i.e., HLA-DR, OKT10 antigen, transferrin receptor, and the Ki-67 nuclear antigen) showed that Tac-antigen expression did not correlate clearly with any of these markers. These data indicate that anti-Tac forms a useful supplement to other monoclonal antibodies for the identification of activated cell subsets in cutaneous lymphoid infiltrates, but they also show that the use of this reagent on cutaneous biopsy specimens is of only limited diagnostic value.

Antibodies, Monoclonal↗
PubMed1986

New sites of human S-100 immunoreactivity detected with monoclonal antibodies.

In a previous paper from this laboratory, the production of monoclonal antibodies recognizing antigenic determinants common to the alpha and beta chains of bovine brain S-100 protein was reported. In the present study, the immunohistochemical labeling patterns of these monoclonal antibodies against a wide range of normal and pathologic human tissues are described, and these results are compared with those obtained using polyclonal anti-S-100 antiserum. Although many of the reactions of the monoclonal antibodies were very similar to those of the polyclonal antiserum (and the previously reported sites of S-100 immunoreactivity) several additional cell types (e.g., thyroid follicular cells, biliary epithelium, pancreatic cells, renal tubules) were labeled by one or both of the monoclonal antibodies. Blocking experiments prove that immunohistochemical differences obtained with monoclonal and polyclonal antibodies are at least partly caused by differences in the repertoire of antigenic determinants on S-100 protein that are recognized by the two species (i.e., mouse and rabbit, respectively). These results indicate that S-100 may be more widespread in human tissues than previously thought, and that its value as a marker of the histogenetic origin of human tumors should be reappraised. It is suggested that the marked variability observed in the reactivity of different tissues in the present study may indicate that S-100 is a heterogeneous group of molecules, and its expression may be related to the functional activity of cells.

Antibodies, Monoclonal↗
PubMed1986

Reed-Sternberg and Hodgkin cells in lymphocyte-predominant Hodgkin's disease of nodular subtype contain J chain.

To throw light on the question of whether B-cell-derived forms of Hodgkin's disease exist, more than 100 cases of Hodgkin's disease (including all four major histologic categories) were investigated for the presence of J chain and were also immunostained for epithelial membrane antigen and the granulocyte-associated antigen X hapten. Reed-Sternberg and Hodgkin cells (RS & H) expressed J chain in 22 cases, 8 of which also expressed epithelial membrane antigen (EMA). X hapten was found in 62 cases, but all of these were J chain negative. J chain-positive RS & H cells were restricted to cases of lymphocyte-predominant disease, while X hapten-positive tumor cells were found frequently in nodular sclerosis, mixed cellularity, and lymphocyte-depletion Hodgkin's disease, but only occasionally in cases of lymphocyte-predominant disease. These findings indicate that nodular lymphocyte-predominant Hodgkin's disease differs from the other subtypes of Hodgkin's disease and that the neoplastic cells are of B-lymphoid origin.

Fluorescent Antibody Technique↗
PubMed1986

Expression of a cell-cycle-associated nuclear antigen (Ki-67) in cutaneous lymphoid infiltrates.

Cryostat sections of skin biopsies from 83 patients with benign or malignant cutaneous lymphoid infiltrates were examined immunohistologically for reactivity with Ki-67 (a monoclonal antibody recognizing a nuclear antigen expressed by cycling cells) using the APAAP immunoalkaline phosphatase labeling method and a double immunoperoxidase/alkaline phosphatase staining technique. Ki-67-positive neoplastic lymphocytes were plentiful in all large-cell lymphoma cases and in one-third of the small-cell lymphomas. Some benign disorders (patch test biopsies, cutaneous lymphocytoma, lichen planus) also contained many Ki-67-positive lymphocytes. These data indicate the value of using Ki-67 to assess the proliferative capacities of the lymphoid cells in cutaneous infiltrates. Use of this technique in the future may have important prognostic and therapeutic implications in the management of cutaneous lymphoid malignancies.

Antibodies, Monoclonal↗
PubMed1986

Atypical cells in lymphomatoid papulosis express the Hodgkin cell-associated antigen Ki-1.

Lymphomatoid papulosis (LyP) is characterized by the presence of large multinucleated cells resembling Reed-Sternberg (RS) cells. Evidence of antigenic similarity between these two cell types has been sought by immunohistologic labeling of 10 biopsies from cases of LyP with monoclonal antibodies against Ki-1 and other RS and Hodgkin (H) cell-associated antigens. In all cases studied, a proportion of the large atypical cells expressed the Ki-1 antigen. On the contrary, in 20 biopsies of benign skin lesions or cutaneous T-cell lymphomas, Ki-1-positive cells were absent or only occasionally present. Furthermore the large atypical cells of LyP also expressed antigens (e.g., T3, T4, HLA-DR, IL-2 receptors) which we have previously demonstrated on RS cells in the majority of cases of Hodgkin's disease (HD). These findings, in conjunction with the observation that Ki-1 antigen expression can be induced on peripheral blood lymphocytes following exposure to phytohemagglutinin or HTLV I, provide evidence that the Ki-1 positive cells in LyP represent activated T cells as RS cells do in many cases of HD.

Antibodies, Monoclonal↗
PubMed1986

Photosensitive dermatitis with actinic reticuloid syndrome: an immunohistological study of the cutaneous infiltrate.

Cryostat sections of skin biopsies from five patients with chronic photosensitivity dermatitis with actinic reticuloid syndrome (PDAR) have been examined immunohistologically by the alkaline phosphatase:anti-alkaline phosphatase staining technique using a panel of 24 monoclonal antibodies against lymphoid cells and their subsets. The lymphoid infiltrates in all cases had an essentially identical cellular composition, containing a mixture of T-lymphocytes, T-cell accessory cells (Langerhans cells) and other types of HLA-DR positive dermal macrophages. In two patients there was an excess of T-helper/inducer cells relative to T-suppressor cells, while in the other three patients the numbers of T-cells in these two subsets were approximately equal. Many of the infiltrating T-cells expressed activation (HLA-DR, interleukin-2 receptor) or proliferation (the Ki67 nuclear antigen, transferrin receptor) associated markers. These data indicate that a T-cell immune response is operative in cutaneous PDAR lesions.

Aged↗
PubMed1986

Immunohistological reactivity pattern of the anti-cutaneous T-cell lymphoma antibody BE2.

It has been reported that the monoclonal antibody BE2, raised against leukaemic T cells, reacts specifically with malignant lymphoid cells and represents a valuable reagent for the early identification of cutaneous T-cell lymphomas. To test this hypothesis, a comprehensive range of nodal and cutaneous biopsies have been examined immunohistologically using single and double immunoenzymatic and immunofluorescent staining methods. BE2 showed a broad range of reactivity, consistently labelling normal endothelial cells, B-lymphocytes in mantle and marginal zones, T-lymphocytes in the paracortex of lymph nodes and medulla of thymus, as well as a variety of different macrophage types, including Langerhans cells and dermal macrophages. Furthermore, although BE2-positive T-lymphocytes were most frequent in malignant lymphomas, they were also found in four of 19 benign dermatoses. We conclude that BE2 is neither T-cell nor tumour-cell specific, and that use of this reagent on tissue sections is unlikely to improve the diagnosis of cutaneous lymphomas.

Antibodies, Monoclonal↗
PubMed1986

T-cell origin of Lennert's lymphoma.

The arrangement of the T-cell receptor and immunoglobulin genes has been analysed in five cases of Lennert's lymphoma. All cases showed rearrangement of the gene coding for the beta chain of the T-cell receptor and a germline configuration of the immunoglobulin genes. This provides strong evidence that Lennert's lymphoma is a T-cell lymphoma.

Antibodies, Monoclonal↗
PubMed1986

Dendritic reticulum cells in reactive lymph nodes and tonsils: an immunohistological study.

There has recently been much interest in the patterns of follicular dendritic reticulum cells (DRC) in pathological lymph nodes, particularly in relation to the phenomenon of DRC break-up (thought to be pathognomonic of AIDS-related lymphadenopathies) and to progressive transformation of germinal centres (as a possible precursor of lymphocyte predominant Hodgkin's disease). In the present study we have immunostained twenty-nine reactive lymph nodes and five tonsils with monoclonal antibody R4/23 (DAKO-DRC) in order to evaluate the frequency of such changes in lymphoid tissue unaffected by AIDS or Hodgkin's disease. Most of the specimens contained typical secondary follicles with clearly defined germinal centres and mantle zones. There were two variants in lymph nodes showing follicular hyperplasia characterized by (i) progressive transformation of germinal centres and (ii) inclusions of nests of small lymphocytes within germinal centres. In each of these types of follicles the compact evenly-distributed meshwork of DRCs, as previously described, was seen. However there were considerable variations in DRC meshwork in each category (the pattern could not be predicted from the morphology) with examples in all three of the DRC break-up previously considered specific for the AIDS related lymphadenopathy. Since none of the lymph nodes and tonsils studied had any known relationship to either Hodgkin's disease or AIDS it is argued that none of the changes in the DRC meshwork observed are specific for these conditions.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Evidence for monoclonal T lymphocyte proliferation in angioimmunoblastic lymphadenopathy.

The arrangement of the T cell receptor and immunoglobulin genes was analysed in lymphoid tissue biopsy specimens from 25 cases of angioimmunoblastic lymphadenopathy. Nineteen cases showed a rearrangement of the gene coding for the beta chain of the T cell receptor, and in one case a clonal rearrangement of immunoglobulin genes was shown (in which the T cell receptor gene was in a germline configuration). These findings indicate that a monoclonal T cell proliferation is present in most cases of angioimmunoblastic lymphadenopathy, and they also correlate with the fact that some patients who present with this disorder subsequently develop a T cell lymphoma.

Cell Division↗