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D Y Mason

Publications and source records attributed to D Y Mason.

At least 253 records · Page 14Linked to original sources
PubMed1984

Freeze-dried paraffin-embedded human tissue for antigen labelling with monoclonal antibodies.

Conventional fixation and paraffin embedding of human tissue destroys most of the antigens detected with currently available antibodies, while cryostat sections give poor morphological detail and require freezer space for storage. However, when tissue was freeze-dried before being embedded in paraffin S then stained for a wide range of antigens recognised by monoclonal antibodies (including T-cell and B-cell antigens), morphological preservation was clearly better, and the labelling reactions were of equal (or greater) intensity, than with cryostat sections. As the number of diagnostically important monoclonal antibodies continues to increase the use of freeze-dried paraffin sections should facilitate the introduction of immunohistological techniques for both routine histopathological diagnostic work and immunological research.

Antibodies, Monoclonal↗
PubMed1984

Immunocytochemical detection of T and B cell populations in routine blood smears.

Immunofluorescence labelling of peripheral blood mononuclear cells is usually done on cells in suspension. This paper describes a procedure based on immuno-alkaline phosphatase staining of routine blood smears. The advantages of this method are that a few drops of blood are sufficient for labelling multiple lymphocyte subpopulations; smears may be stored for long periods before labelling; it is unnecessary to isolate a mononuclear cell fraction before labelling; labelled preparations can be stored; and the morphological features of labelled cells are shown clearly. The technique was used to label T cells and their subsets, B cells, and HLA-DR antigen in blood smears from 15 normal donors, from 7 patients with infectious mononucleosis, from 1 patient with clinically proven AIDS, and from 1 symptom-free subject at risk of AIDS. The normal T helper/suppressor ratio of 1 X 95 was reversed in all of the last three groups of subjects, the mean being 0 X 34 for infectious mononucleosis; the value was 0 X 22 in the AIDS patients. Immuno-alkaline phosphatase labelling of routine blood smears seems to be a valuable method for studying abnormalities in circulating lymphocyte subpopulations and lends itself to mass screening for altered T helper and T suppressor subjects-for example, in blood donors.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Isolation of follicular dendritic cells from human tonsils and adenoids. II. Immunocytochemical characterization.

Follicular dendritic cells (FDC) are specialized cells found only within lymphoid follicles. They bind immune complexes and play a role in the presentation of antigen to follicular B cells and in the generation of B cell memory. In the present report the isolation of FDC from human tonsils and adenoids is described. These isolated cells have an unusual spherical arrangement and enclose lymphocytes within extensions of their membranes. Their ultrastructural features are similar to those observed in situ. The reactivity of isolated FDC with a number of monoclonal antibodies was analyzed by immunofluorescence and by immunostaining (at the electron microscopic level) with colloidal gold. In keeping with the results of previous investigations on tissue sections IgM, IgG and IgA (but not IgD) can be detected on the surface of isolated FDC, as can C3b receptors and the FDC-associated antigen detected by monoclonal antibody R4/23. The immunoglobulins associated with FDC are mostly embedded in an electron-dense material. The majority of the lymphoid cells enclosed within the membrane extensions of FDC are of B cell type. These results suggest that isolated FDC may be suitable for further in vitro investigation of their role in the humoral immune response.

Adenoids↗
PubMed1984

The immunocytochemical detection of axillary micrometastases in breast cancer.

The histological detection of tumour metastases in axillary lymph nodes from cases of breast carcinoma is of major prognostic significance, but may be difficult when metastases are of microscopic size. We have therefore investigated whether immunohistological techniques can increase the accuracy of metastasis detection in axillary lymph nodes. Forty-five cases of breast carcinoma were studied, in all of whom the axillary lymph nodes had been reported as free of metastases. Paraffin sections from these cases were stained by immunoenzymatic techniques, using monoclonal antibodies directed against human milk fat globule membrane antigen ("anti-EMA") and against epithelial intermediate filaments ("anti-keratin"). In 4/12 cases of lobular carcinoma and in 3/33 cases of ductal carcinoma, previously unsuspected micrometastases were revealed by immunohistological staining, representing an overall increase in detection rate of 15% (and of 33% for the lobular carcinoma cases). In addition to this group of 45 histologically "negative" biopsies, 12 samples were studied in which only a proportion of the nodes had been reported as containing tumour. In 5 of these cases immunostaining revealed previously undetected metastases. These findings suggest that immunohistological analysis may have a routine role to play in the staging of breast carcinoma. It is noted that the 15% increase in diagnostic accuracy achieved in the present study is comparable to the proportion of breast carcinoma patients in whom disseminated disease develops despite their axillary lymph nodes being reported as tumour-free at the time of surgery.

Alkaline Phosphatase↗
PubMed1984

An immunohistological study of testicular germ cell tumours using two different monoclonal antibodies against placental alkaline phosphatase.

Using two monoclonal antibodies directed against placental alkaline phosphatase (H17E2 and D20L) the immunohistological staining of testicular germ cell tumours was compared with that of a wide range of normal and malignant tissues. All seminomas and malignant teratomas tested gave strong positive labelling with H17E2 but were either negative or only patchily positive with D20L. Neither antibody gave any positive reaction on the normal tissues tested. All other malignancies were negative with both antibodies apart from two cases of ovarian and one case of endometrical cancer (strongly stained by H17E2) and three cases of colonic carcinoma (weakly and patchily stained by both H17E2 and D20L). This indicates that germ cell neoplasms generally express a form of placental alkaline phosphatase recognised by antibody H17E2.

Alkaline Phosphatase↗
PubMed1984

The differential diagnosis of routinely processed anaplastic tumors using monoclonal antibodies.

The value of immunohistological labeling with a panel of monoclonal antibodies in the diagnosis of routinely processed surgical biopsies has been assessed. The cases examined consisted of an unselected series of tumor biopsies referred during a 12-month period because of doubt as to the nature of the neoplasm and are representative of the type of diagnostic problem regularly encountered in routine surgical pathology. In 30 of the 38 cases studied, reactivity with monoclonal antileukocyte antibody (and nonreactivity with monoclonal antiepithelial antibodies) indicated that the tumor was a lymphoma. Seven of the remaining eight cases gave the reverse reaction pattern and therefore were classified as carcinomas, while one biopsy was unreactive with all antibodies. Review of the clinical details in each case showed that the clinical management in several instances was influenced by establishing the correct diagnosis and it therefore is suggested that immunohistologic examination should be used more widely in the study of tumors that give rise to diagnostic difficulty.

Aged↗
PubMed1984

Characterization of benign cutaneous lymphocytic infiltrates by monoclonal antibodies.

Skin biopsies from nine patients with a histological and/or clinical diagnosis of cutaneous lymphocytoma, lymphoplasia or Jessner's lymphocytic infiltrate were examined by immunoenzymatic labelling with a panel of monoclonal antibodies against lymphocytes and accessory cells. Similar cellular constituents were demonstrated in the biopsies from three patients with lymphocytoma, two with lymphoplasia and two with atypical lymphocytes, but a protracted benign clinical course. The infiltrates from these patients consisted of T cells, Langerhans cells, related HLA-DR positive dendritic dermal cells and clusters of polyclonal B cells. In four patients, the B cell clusters contained B cell accessory follicular dendritic cells, and thereby closely resembled the B cell follicles seen in lymphoid organs. The T cells were predominantly T helper/inducer cells and in all patients the T cells expressed HLA-DR. One patient diagnosed as lymphocytoma cutis differed from the other patients by having no detectable B cells. One patient with Jessner's lymphocytic infiltrate differed from the other patients by having a marked relative predominance of T suppressor/cytotoxic cells. These data suggest that cutaneous lymphocytoma and lymphoplasia are basically similar disorders which may be considered to be exaggerated immune responses, whereas Jessner's lymphocytic infiltrate may be a separate entity. Immunological analysis may assist in establishing a definite diagnosis in cases of lymphocytoma or lymphoplasia with atypical cytological features.

Adolescent↗
PubMed1984

Immunohistological analysis of human bone marrow trephine biopsies using monoclonal antibodies.

This paper describes the use of a recently developed immuno-alkaline phosphatase method (the 'APAAP' technique) for labelling frozen sections of undecalcified bone marrow biopsies with monoclonal antibodies, including reagents reactive with T cells and their subsets, B cells, glycophorin, HLA-DR antigen, common ALL antigen, epithelial cells and megakaryocytes. Use of an immuno-alkaline phosphatase technique avoids problems due to endogenous enzyme activity encountered when staining bone marrow by immunoperoxidase procedures. Immunohistological labelling of frozen trephine biopsies is of particular value when it is impossible to aspirate marrow particles and for identifying cells which do not readily enter suspension (e.g. dendritic reticulum cells or stromal cells). Details are given of cases in which immunohistological analysis was used for the phenotyping of acute leukaemias, for the differential diagnosis of intramedullary T and B cell proliferations, and for identifying bone marrow metastases.

Alkaline Phosphatase↗
PubMed1984

An immunohistological study of the cellular constituents of Hodgkin's disease using a monoclonal antibody panel.

Cryostat sections of lymphoid tissue from 44 cases of Hodgkin's disease were analysed by immunoperoxidase staining using a panel of monoclonal antibodies which included reagents reactive with T cells and their subsets, B cells, HLA-DR, Ig, dendritic reticulum cells and C3b receptor. A wide spectrum of immunohistological patterns was observed ranging from cases in which T cells were numerous (B cells being absent or present in only small numbers) to cases in which very prominent B cell follicles were present. These follicles contained a meshwork of dendritic reticulum cells and were composed of polyclonal B cells (as assessed by light chain expression). T cells were present in small numbers within these B cell follicles, often clustered in a thin rim around individual Reed-Sternberg and Hodgkin's cells. All B cell-rich cases were examples of lymphocyte predominant Hodgkin's disease. Assessment of the T cell helper/suppressor ratios was hindered by the fact that both anti-helper antibodies (OKT4 and anti-Leu 3a) reacted with macrophages. However the majority of cases appeared to contain a normal excess of T helper cells. HLA-DR was strongly expressed in T cell rich areas, on Reed-Sternberg and Hodgkin's cells, on vascular endothelium and on numerous infiltrating cells in the fibrous tissue areas in cases of nodular sclerosing disease. Reed-Sternberg and Hodgkin's cells were not labelled by either anti-fibronectin or by antibodies reactive with dendritic reticulum cells (anti-C3b receptor and antibody R4/23).

Antibodies, Monoclonal↗
PubMed1984

An immunohistological study of benign and malignant skin tumours: epithelial aspects.

Biopsies of normal skin and benign and malignant skin tumours were studied immunohistologically with nine monoclonal antibodies. The study showed that monoclonal antibodies can clearly delineate antigens expressed in different regions of normal skin and that, in general, tumours retain the antigenic pattern characteristic of the region from which they have arisen. These findings indicate the potential value of analysing these patterns of antigenic expression with a panel of monoclonal antibodies both for understanding the pathogenesis of skin tumours (e.g. basal cell carcinomas) and in their differential diagnosis (e.g. squamous cell carcinoma versus keratoacanthoma).

Antibodies, Monoclonal↗
PubMed1984

Langerhans' cells and T cells in human skin tumours: an immunohistological study.

In this study normal skin and a range of skin tumours, both benign and malignant, have been examined using monoclonal antibodies to identify the distribution and morphology of Langerhans' cells and T cells, the distribution of T lymphocytes and their subsets have been analysed using monoclonal anti-T cell antibodies. The results indicated that Langerhans' cells can be reliably identified in both normal and malignant skin biopsies using monoclonal antibodies. A striking finding to emerge was that in benign skin lesions Langerhans' cells were increased, whereas in malignant tumours they were not only markedly depleted or absent but also grossly stunted and deformed in outline. The majority of lymphocytes surrounding these skin tumours were shown to be T cells with helper cells outnumbering suppressor cells by a ratio from 2 to 5:1. This study shows the usefulness of immunohistological techniques using monoclonal antibodies for examining the morphology and distribution of Langerhans' cells in skin pathology. In addition they are particularly appropriate for identifying their topographical relationships with other immunologically important cells such as T cells.

Basal Cell Carcinoma↗
PubMed1984

Identification of large cell undifferentiated tumours in lymph nodes using leucocyte common and keratin antibodies.

A total of 43 cases undifferentiated large cell tumours presenting in lymph nodes were stained by immunoperoxidase techniques using antibodies against keratin and a leucocyte-associated glycoprotein. In 26 cases diagnosed histologically as metastatic carcinoma, staining with the keratin antibody suggested a squamous cell origin in 11 cases. This was supported by microscopic observation of intracellular filaments in seven cases. In 15 patients in whom the original diagnosis was uncertain, a definite diagnosis was possible in all cases following immunoperoxidase staining with the two antibodies and most of these proved to be large cell lymphomas. In two cases a potentially major diagnostic error was detected. It is suggested that the staining of undifferentiated human neoplasms using combinations of antibodies reactive with epithelial and lymphoid cells should result in much greater diagnostic accuracy in the field of large cell tumours presenting in lymph nodes.

Adolescent↗
PubMed1984

Immunohistochemical study of mammary and extra-mammary Paget's disease.

Paraffin sections of 13 cases of Paget's disease (six mammary and seven extra-mammary) were investigated with mono- and polyclonal anti-carcinoembryonic antigen (CEA) and with monoclonal anti-human milk fat globule membrane antigen (HMFG). One of these cases was also analysed in cryostat sections with monoclonal anti-cytokeratin and anti-keratin. Three immunohistochemical labelling patterns were identified: (I) All six cases of mammary Paget's disease were positive for anti-HMFG and negative with monoclonal anti-CEA (although they stained to a variable degree with polyclonal anti-CEA). (2) Two cases of extra-mammary Paget's disease (both anal location) were positive with monoclonal anti-CEA and only weakly stained for HMFG suggesting epidermal spread from a colo-rectal carcinoma. (3) The other five cases of extra-mammary Paget's disease were negative or weakly stained for CEA and positive for HMFG. We speculate that this group of cases represents epidermotropic eccrine carcinoma. The immunohistochemical use of monoclonal anti-HMFG and -CEA is helpful in the diagnosis of Paget's disease; moreover it gives information about the origin of the primary tumour.

Antibodies, Monoclonal↗
PubMed1984

Immunoenzymatic typing of lymphoplasmacytoid skin infiltrates.

Monoclonal immunoglobulin-producing lymphomas (immunocytomas, plasmacytomas, and immunoblastomas) constitute 15 to 20% of all cutaneous lymphomas. Their differentiation from polymorphous lymphoplasmacytoid inflammatory or pseudolymphomatous infiltrates may be difficult if sections are stained for a single light chain only. It was the aim of the study to elucidate the ratio of the kappa- to lambda-positive cells in 10 lymphoproliferative, 5 pseudolymphomatous, and 42 inflammatory lymphoplasmacytoid cutaneous infiltrates and to characterize them by the type of Ig (alpha, gamma, mu, kappa, or lambda) synthesized intracellularly. An indirect immunoenzymatic double-labeling method (alkaline phosphatase and peroxidase) was used for the simultaneous demonstration of kappa and lambda light chains and alpha, gamma, and mu heavy chains in paraffin sections. Ig-producing lymphomas of the skin show patchy monoclonal proliferations of cells synthesizing kappa IgM in almost 50% of the cases (5 of 10). Monoclonality is claimed if the ratio of lambda- to kappa-positive cells is at least 1:10, or vice versa. In polyclonal inflammatory and pseudolymphomatous infiltrates, the lambda/kappa ratio never exceeds 1:5. The most common cell type found in these reactive infiltrates produces gamma heavy chain; some produce alpha chain, but only a few produce mu chain. In high-grade malignant lymphomas, the tumor cells may lose their capacity for Ig production.

B-Lymphocytes↗
PubMed1984

Nature of non-B, non-T lymphomas: an immunohistological study on frozen tissues using monoclonal antibodies.

In a previous study employing conventional immunological marker analysis we found that 17% of high grade malignant lymphomas were devoid of cytoplasmic and membrane immunoglobulin and also sheep erythrocyte receptors. Cryostat sections from 24 of these cases (four of low grade and 20 of high grade malignancy) were stained with a panel of 30 monoclonal antibodies and six polyclonal antisera using a sensitive immunoperoxidase method. All tumours expressed the leucocyte common antigen (detected by monoclonal antibody 2D1) and all lacked epithelial cytokeratin (monoclonal antibody LE61), confirming their haematopoietic origin. All but one of the lymphomas expressed antigens characteristic of either B cells (17 cases) or T cells (six cases), while one case (morphologically a centroblastic lymphoma) had an unusual dual phenotype in which strong staining for T6 (marker of immature T cells) was associated with expression of the pan B lymphocyte antigens detectable with To15, anti-B1, anti-Leu12. This case was therefore classified as a B cell lymphoma showing aberrant expression of the T6 antigen. The pan B cell antibodies (To15, anti-B1, anti-Leu12) all appeared highly specific and sensitive, but the simultaneous use of all three monoclonal antibodies was necessary to detect the B cell nature in each of the 18 lymphomas. A wider panel of monoclonal antibodies was required to detect T lymphomas since these often disclosed atypical and restricted phenotypes. To15 and UCHT1 were the most reliable antibodies for the detection of B and T cell neoplasms, respectively. We conclude that most, if not all, "non-B, non-T" lymphomas are of either B or T lymphocyte origin and that monoclonal antibodies provide indispensable tools in their classification and diagnosis.

Antibodies, Monoclonal↗
PubMed1984

Immunoenzymatic labeling of monoclonal antibodies using immune complexes of alkaline phosphatase and monoclonal anti-alkaline phosphatase (APAAP complexes).

A murine monoclonal antibody specific for calf intestinal alkaline phosphatase has been prepared and used in an unlabeled antibody bridge technique for labeling monoclonal antibodies. This procedure--the alkaline phosphatase monoclonal anti-alkaline phosphatase (APAAP) method--gives excellent immunocytochemical labeling of tissue sections and cell smears, comparable in clarity and intensity to that achieved with immunoperoxidase labeling. If the enzyme label is developed with a naphthol salt as a coupling agent and Fast Red or hexazotized new fuchsin as a capture agent, a vivid red reaction product is obtained which is very easily detected by the human eye. For this reason the APAAP technique was found particularly suitable for labeling cell smears (for both cytoplasmic and surface-membrane antigens) and for detecting low numbers of antigen-bearing cells in a specimen (e.g., carcinoma cells in a malignant effusion). It was found possible to enhance the intensity of the APAAP labeling reaction substantially by repeating the second and third incubation steps (i.e., the unlabelled "bridge" antibody and APAAP complexes). The APAAP technique was superior to immunoperoxidase labeling for staining tissues rich in endogenous peroxidase, and could be used in conjunction with immunoperoxidase methods for double immunoenzymatic staining. The method was also applicable to the detection of antigenic molecules following their electrophoretic transfer from SDS-polyacrylamide gels to nitrocellulose sheets ("immunoblotting").

Alkaline Phosphatase↗
PubMed1984

Immature sinus histiocytes. Their identification as a novel B-cell population.

The true nature of cells of "immature sinus histiocytosis" (ISH) is uncertain because they lack the typical features of normal histiocytes when analyzed by enzyme cytochemistry or electron microscopy. In the present study the antigenic profile of ISH cells has been analyzed by immunohistologic techniques in six cases of Piringer's lymphadenitis with the use of a large panel of monoclonal and polyclonal antibodies reactive with the major cell types of the hematolymphoid system. The results obtained indicate that ISH cells consistently lack markers found on cells of the monocyte/macrophage series, myeloid cells, interdigitating reticulum cells, follicular dendritic reticulum cells, T cells, or Ki-1-positive cells. They constantly express B-cell antigens and HLA-DR and (on a variable proportion of cells) surface immunoglobulin. The application of antibodies reactive with different B-cell subsets showed that the cells of ISH do not correspond to any previously described B-cell population, eg, pre-B cells, germinal center cells, follicular mantle lymphocytes, or marginal zone cells. Furthermore, ISH cells and germinal center cells are found in association with clearly different cell types. These findings indicate that ISH cells represent a B-cell population at a previously undescribed differentiation stage, occurring only under certain circumstances (eg, in toxoplasmosis or AIDS). It is proposed that the term "immature sinus histiocytosis" be replaced by "B-cell sinus reaction."

Antibodies, Monoclonal↗