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D Y Mason

Publications and source records attributed to D Y Mason.

At least 217 records · Page 12Linked to original sources
PubMed1986

Reactivity of T lymphotropic retrovirus antibody (12/1-2) in man: comparison of epidermis with other epithelial cells.

The reactivity of a monoclonal antibody against human T lymphotropic retrovirus (antibody 12/1-2, recognising the HTLV-1 p19 internal core viral protein) with benign and malignant cutaneous biopsy specimens was examined and compared with results obtained on normal skin, on various other human cells and tissues, and on immunoblotted extracts of tonsil squamous epithelium. In keeping with previous studies, 12/1-2 labelled a proportion of the thymic epithelial stroma and the entire layer of basal cells in stratified non-keratinized and keratinized epithelium. Furthermore, antibody 12/1-2 reacted with basal cell carcinomas and showed an essentially identical staining pattern in normal skin, cutaneous T cell lymphomas, and a range of benign dermatoses. The dot blot preparations showed that 12/1-2 recognised an antigen associated with keratin intermediate filaments. These data indicate that antibody 12/1-2 forms a useful marker for subsets of epithelial cells, which presumably participate in T cell education, and that a range of cutaneous disorders of widely different aetiology show no abnormalities in epithelial expression of this antigen.

Antibodies, Monoclonal↗
PubMed1986

Immunocytochemical characterisation of cutaneous lymphomas other than mycosis fungoides.

The immunophenotypic properties of 25 cutaneous non-Hodgkin lymphomas other than mycosis fungoides or Sezary syndrome were investigated and correlated with clinical and histopathological data. The 11 low grade lymphomas were all of B cell origin, whereas the 14 high grade lymphomas comprised B and T cell tumours, true histiocytic proliferations, and one "nul" cell lymphoid neoplasm. For the high grade lymphomas correct prediction of the immunological phenotype based on morphological criteria was only possible in three cases. In contrast, all of the low grade lymphomas showed the non-epidermotropic infiltration pattern considered to be characteristic of cutaneous B cell tumours. For these conditions, however, immunophenotypic investigations provided a convenient means of improving discrimination between benign (polyclonal) and malignant (monoclonal) lesions, and also showed similarities with nodal lymphomas in terms of expression of lymphoid subset markers and composition of the non-neoplastic white cell infiltrate. No differences were identified between primary and secondary or concurrent cutaneous and extracutaneous lymphomas. Cutaneous non-Hodgkin lymphomas other than mycosis fungoides or Sezary syndrome constitute a heterogeneous group of neoplasms and most of these disorders are likely to represent cutaneous equivalents of nodal malignancies. Immunophenotypic investigations form a useful supplement to their histogenetic characterisation and may provide a common conceptual basis for their classification.

Adolescent↗
PubMed1986

New approach to assessing lung tumours in man.

One hundred and four surgically resected lung tumours were labelled in either cryostat or freeze dried sections with a monoclonal antibody (Ki67), which reacts with a nuclear antigen expressed by proliferating cells. The tumours were categorised semiquantitatively into four proliferative grades, a classification that can be performed rapidly and reproducibly by the pathologist. In keeping with previous cell kinetic studies all small cell carcinomas had high proliferation rates, whereas the carcinoid tumours were in the lowest grade. In contrast, the adenocarcinomas (27 cases) and squamous cell carcinomas (63 cases) varied widely in their proliferative state, in keeping with their heterogeneous, morphological, and clinical behaviour. Immunocytochemical labelling of lung tumour biopsy specimens with antibody Ki67 is a simple technique within the scope of routine surgical pathology laboratories, which might enable these tumours to be classified according to their proliferative status and treatment to be selected accordingly.

Adenocarcinoma↗
PubMed1986

Human lung tumours may coexpress different classes of intermediate filaments.

Ninety four pulmonary neoplasms were examined immunocytochemically with two or three different monoclonal antibodies against the intermediate filament proteins cytokeratin, neurofilament, vimentin, and desmin. In normal tissues these have a different and non-overlapping distribution, and it is generally believed that tumours maintain the same pattern of expression as the tissues from which they arise. In this report, however, the coexpression of at least two (and less commonly three or four) different intermediate filaments was seen in 40% (37 of 94) of the cases of lung cancer. These results, especially if confirmed in other common types of human malignancy, have considerable implications for the use of anti-intermediate filament antibodies in diagnostic pathology.

Adenocarcinoma↗
PubMed1986

A monoclonal antibody recognizing the p150/95 leucocyte differentiation antigen.

A monoclonal antibody KB90 recognizing a molecule containing two polypeptide subunits of 140 and 98 kd is described. Biochemical studies following high pH dissociation of the molecule showed KB90 to bind to an epitope on the 140 kd subunit. The molecule recognized by KB90 appears to correspond to the p150/95 molecule in the family of leucocyte differentiation antigens of which the LFA-1 and Mac-1 molecules are members. Analysis of the immunocytochemical reactivity of KB90 shows that it stains monocytes, tissue macrophages, granulocytes and a small population of lymphocytes. These reactions are clearly distinct from those of the LFA-1 and Mac-1 molecules.

Animals↗
PubMed1986

Mantle zone lymphoma. Immuno- and enzymehistochemical studies on the cell of origin.

Using in-situ immuno- and enzymehistochemical techniques, the phenotype of the neoplastic cells in seven cases of mantle zone lymphoma (MZL) was compared to that in seven cases of nodular poorly-differentiated lymphocytic lymphoma (NPDLL). The neoplastic nodules in MZL consisted of medium-sized lymphoid cells with slightly irregular nuclei and finely dispersed chromatin, expressing monoclonal surface IgM or IgM plus IgD, and displaying membranous alkaline phosphatase (ALP) activity. These cells proliferated around follicular centers that demonstrated a polyclonal pattern of reactivity for both types of light chains and a distorted meshwork of dendritic reticulum cells. The neoplastic nodules in NPDLL consisted of small lymphoid cells with markedly irregular nuclei and coarsely granulated chromatin, expressing monoclonal surface IgM and lacking ALP-activity. These tumor cells also frequently expressed transferrin receptor and common acute lymphoblastic leukemia-antigen (CALLA). The neoplastic nodules showed an undistorted meshwork of dendritic reticulum cells, and were occasionally bordered by remnants of polyclonal lymphocytic coronas. These results confirm the previous suggestion that NPDLL arises from a cell type that is a normal constituent of follicular centers, whereas MZL arises from the lymphocytic corona. The morphological, enzyme- and immunohistochemical features of MZL cells strongly suggest that MZL arises from marginal zone lymphocytes, a subset of corona lymphocytes that expresses ALP-activity, high IgM and low IgD-levels.

Adult↗
PubMed1986

Cells bearing class II MHC antigens in the human placenta and amniochorion.

Immunohistological techniques have been used to study the stromal cells of the human placenta in both the chorionic villous mesenchyme and the connective tissue underlying the amnion. Throughout gestation many of these cells express an antigen (3C10) that is found on mononuclear phagocytes but not on dendritic cells or epidermal Langerhans cells. In the first and second trimesters the placental cells also react with a monoclonal antibody (NA1/34) to the human thymocyte antigen (CD1), a lymphocyte differentiation antigen expressed by cortical thymocytes and Langerhans cells; expression of this antigen diminishes as gestation advances. In contrast, an antibody to a different epitope of CD1 (OKT6) does not bind. Class II MHC antigens are not present in the first trimester but are acquired by increasing numbers of placental macrophages from the second trimester onwards. It is possible that the placenta has significant immune functions and that, by term, placental macrophages may be capable of antigen presentation.

Amnion↗
PubMed1986

A new monoclonal antibody (KB61) recognizing a novel antigen which is selectively expressed on a subpopulation of human B lymphocytes.

The present paper describes a new monoclonal antibody (KB61) raised against hairy cell leukaemia cells. Antibody KB61 recognizes a molecule of approximately 40,000 molecular weight on human B cells. It reacts with B lymphocytes in the peripheral blood, in primary lymphoid follicles, in the mantle zone of secondary follicles, in interfollicular areas and in splenic marginal zone areas. However, germinal centre lymphoid cells do not express the antigen recognized by antibody KB61. The antibody shows limited reactivity outside the lymphoid system, i.e. polymorphs, tissue macrophages endothelial cells in the hepatic sinusoids. Antibody KB61 discriminates between different types of B-cell malignancies, reacting with the neoplastic cells in hairy cell leukaemia, chronic lymphocytic leukaemia (of B-cell type), prolymphocytic leukaemia and centrocytic lymphoma, but not with acute lymphoblastic leukaemia, germinal centre-derived lymphomas (other than centrocytic), Burkitt's lymphoma and lymphoblastic lymphoma. Antibody KB61 may be of value in the study of B-cell subpopulations and in the differential diagnosis of B-cell neoplasms.

Antibodies, Monoclonal↗
PubMed1986

Immunohistological analysis of human mononuclear phagocytes and dendritic cells by using monoclonal antibodies.

Mononuclear phagocytes and dendritic cells were analyzed in detail with a panel of monoclonal antibodies by immunoalkaline phosphatase and immunofluorescence techniques. The panel included two antibodies (KB90 and SHCL3) against the two chain membrane constituent, P150,95, an antibody (Mo1) against C3bi receptor, an antibody (To5) against C3b receptor, and two antibodies (Mo2 and UCHM1) against a single chain glycoprotein with a molecular weight of 55 to 60 previously found on monocyte/macrophages. In addition, the panel contained several antibodies including EBM11, LeuM3 and FMC32 whose molecular specificities are not known at present. Frozen sections of spleen, bone marrow, thymus, lymph node, liver, brain, lung, kidney, colon, and skin were examined. Several populations of mononuclear phagocytes and dendritic cells could be distinguished on the basis of their reactivity with the antibody panel. Populations of macrophages resident in parenchymal organs had reaction patterns distinct from those of circulating macrophages. Many of the antibodies in the panel reacted with both macrophages and dendritic cells suggesting a close cytogenic, if not functional, relationship between these cells. There was wide variability in the reactions of macrophages and dendritic cells in different tissue and less variability among cells within individual anatomic locations.

Antibodies, Monoclonal↗
PubMed1986

An evaluation of the utility of anti-granulocyte and anti-leukocyte monoclonal antibodies in the diagnosis of Hodgkin's disease.

The immunoreactivity of six different monoclonal antigranulocyte antibodies (Leu M1, TG1, 3C4, BY/87a, BY/37a, and 3CD1) has been evaluated in 23 cases of Hodgkin's disease (7 lymphocyte predominant, 12 nodular sclerosing, and 5 mixed cellularity); in a variety of non-Hodgkin's lymphomas and in a series of reactive and benign lesions of lymph nodes. Applying a monoclonal antibody (PD7/26) to leukocyte common antigen (T200), we have also investigated reports that the L&H variants in nodular lymphocyte predominant Hodgkin's disease are strongly immunoreactive for leukocyte common antigen in contrast to the lack of reactivity of Reed-Sternberg (RS) cells and variants thereof in other forms of Hodgkin's disease. All six monoclonal anti-granulocyte antibodies reacted against RS cells and "Hodgkin's cells" in the nodular sclerosing (NSHD) and mixed cellularity (MCHD) types, with strong cell membrane and juxtanuclear (Golgi) staining. In contrast an anti-leukocyte antibody PD7/26 was unreactive with RS cells and variants thereof in NSHD and MCHD. On the other hand, RS cells and L&H variants thereof in the nodular L&H form of Hodgkin's disease (nodular lymphocyte predominant type) showed reactivity with PD7/26 but not with the anti-granulocyte markers. Rare L&H cells in 2 cases of diffuse lymphocyte predominant type showed reactivity with some, but not all, of the anti-granulocyte antibodies. These findings provide further support for the concept that the nodular L&H type of Hodgkin's disease represents an entity distinct from other forms of this disorder. Our studies also demonstrate the usefulness of these immunoperoxidase techniques when applied to formalinfixed, paraffin-embedded tissues.

Antibodies, Monoclonal↗
PubMed1985

Malignant histiocytosis of the intestine: a T-cell lymphoma.

Malignant lymphoma complicating coeliac disease has been characterised on morphological and immunocytochemical grounds as malignant histiocytosis of the intestine (MHI). Fresh tissue from four cases of MHI was studied by means of a panel of monoclonal antibodies; in three cases tumour DNA was studied for immunoglobulin and T-cell receptor (TCR) gene rearrangement. Immunocytochemistry showed a T-cell phenotype in all four cases, confirmed by the demonstration of a rearranged TCR beta-chain gene in the three cases studied. Lymphoma complicating coeliac disease thus appears to be of T-cell, rather than histiocyte, origin.

Adult↗
PubMed1985

Clinical importance of analysing malignant tumours of uncertain origin with immunohistological techniques.

The value of immunohistology in the histopathological diagnosis of malignant tumours was evaluated in a series of 120 consecutive routinely processed biopsy specimens, all of which had been referred by histopathologists because of diagnostic difficulties. The specimens were analysed by means of a panel of monoclonal and polyclonal antibodies reactive with antigens which resist routine tissue processing. The tumours had previously been considered unclassifiable (24 cases) or categorised as probable carcinomas (43 cases) or lymphomas (53 cases). All but 8 of the 120 cases could be classified with the immunohistological technique. Lymphoma was the commonest diagnosis (66%) and accounted for 29 of the 43 cases initially thought most likely to be anaplastic carcinomas. Immunohistological methods can now resolve the majority of difficulties arising over the histological diagnosis of malignant tumours, and these methods should therefore be used on a wide scale by diagnostic histopathology laboratories.

Antibodies, Monoclonal↗
PubMed1985

T-helper cell lymphoma involving the lymph nodes and skin. A clinical, morphologic, and immunohistochemical analysis of five cases.

The clinical, morphologic, and immunohistochemical features of 5 cases of peripheral T-cell lymphoma with lymph node and skin involvement are reported. All patients were male and presented with generalized lymphadenopathy and skin lesions. Lymph node biopsy specimens showed a diffusely growing, pleomorphic, atypical lymphoid infiltrate composed of markedly irregular small and large cells. The stroma consisted of plasma cells, eosinophils, epithelioid histiocytes, and an increased number of small blood vessels. A similar neoplastic infiltrate was observed in the cutaneous nodules that developed in three patients. Immunohistochemistry on frozen tissue sections of lymph nodes using a broad panel of monoclonal antibodies revealed that the neoplastic cells were reactive with anti-T-cell antibodies, the majority of them belonging to the helper/inducer T-cell subset. Stromal plasma cells contained polyclonal immunoglobulins. It is concluded that the malignant lymphoma of peripheral helper/inducer T-cell origin observed in these five patients represents a variant of a mixed, blastic/cell T-cell lymphoma, characterized by a peculiar stromal component and skin involvement.

Aged↗
PubMed1985

Normal and neoplastic Langerhans cells: phenotypic comparison with other types of macrophages.

The antigenic properties of normal epidermal Langerhans cells and their neoplastic counterparts (histiocytosis X cells) were compared with those of other types of macrophages, by immunohistochemical staining of skin and lymph node biopsies with a panel of mono-clonal antibodies. The phenotype of Langerhans cells, histiocytosis X cells, dermal macrophages and interdigitating reticulum cells were similar (HLA-DR+, OKT 6+/-, Leu3+/-, C3-receptor-, Ig-complex-, R4/23-, MO2-), and differed markedly from those of follicular dendritic cells (HLA-DR-, OKT6-, Leu3-, C3 receptor+, Ig+, R4/23+, MO2-, and histiocytic reticulum cells (HLA-DR+/-, OKT6-, Leu3+/-, C3-receptor+, Ig-complex+, R4/23-, MO2+/-). This indicates that Langerhans cells are related to the interdigitating reticulum cells found in the T cell areas of lymphoid organs, and demonstrates that Langerhans cells do not express C3b, C3bi or C3d receptor molecules. Our data also emphasise that the Leu3 antigen is not restricted to cells of the T cell lineage.

Antibodies, Monoclonal↗
PubMed1985

Benign and malignant lymphocytic skin infiltrates: immunological patterns recognized by immunohistochemical staining with monoclonal antibodies.

Skin biopsies from 150 patients with cutaneous lymphoma, premalignant or "pseudolymphomatous" conditions and benign dermatoses were examined by immunoenzymatic staining of frozen sections with a panel of monoclonal antibodies against lymphocytes, macrophages and accessory cells. Two patterns of infiltration were identified. In one of these T cells associated with Langerhans cells and HLA-DR-positive macrophages of dendritic morphology, were seen. In the other B cell follicles were present in addition to the above type of infiltrate. The latter pattern was restricted to patch tests biopsies, cutaneous lymphocytomas, and malignant lymphomas of B-cell origin. It is concluded that lymphocytic skin infiltrates are divisible into different patterns of immunological reactions similar to those seen in lymphoid organs.

Antibodies, Monoclonal↗