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C A Feltkamp

Publications and source records attributed to C A Feltkamp.

34 records · Page 2Linked to original sources
PubMed1981

A malignant tumor arising from interdigitating cells; light microscopical, ultrastructural, immuno-and enzyme-histochemical characteristics.

A tumor in a 37 years old male is described in which the tumor cells appeared to be derived from interdigitating cells normally found in the T-cell area of lymph nodes. The patient presented with superior vena caval obstruction due to a mediastinal mass, followed by lymph node enlargement and skin lesions leading to death within 4 months. The tumor cells lacked immune markers for lymphocytic cells. They showed Ia-like antigens and high adenosine triphosphatase activity, while acid phosphatase and alpha-naphthyl acetate esterase activity was absent. Their fine morphology was strikingly similar to that of interdigitating cells. A combination of these data led us to the conclusion that this tumor represents a specific subtype of the tumors derived from the mononuclear phagocyte system, namely a sarcoma of interdigitating cells.

Adult↗
PubMed1980

Non-Hodgkin's lymphoma. Immunohistochemical and electron microscopical findings in relation to lightmicroscopy. A study of 74 cases.

From 74 patients with non-Hodgkin's lymphoma (NHL), fresh biopsy material from involved tissue was investigated histochemically and by light and electron microscopy. The results were compared with the light microscopical conclusions based on three currently utilized classifications, namely of Rappaport, Lukes, and Lennert. The separate groups of low-grade NHL appeared to consist of homogeneous cell populations, both in immunohistological as well as in enzymehistochemical and electron microscopical sense. On the contrary, high-grade NHL constituted a heterogeneous group in which supplementary (immunohistochemical, enzymehistochemical, and electron microscopical) investigation is very useful. All NHLs reacted with anti-human lymphocyte serum, including the so-called histiocytic NHLs according to the Rappaport classification, which proves their lymphocytic origin. Consequently the prefix "histiocytic" should be altered in a morphogenetically correct way. Without exception the B-cell NHLs were characterized by the presence of monoclonal immunoglobulin on the cell membrane and/or intracytoplasmically. In a part of the immunologically non-T-/non-B-/("null cell") NHLs, a B-cell origin was indicated by the presence of ATPase and/or 5' nucleotidase and a T-cell origin by the presence of dot-like acid phosphatase.

Adenosine Triphosphatases↗
PubMed1979

Rigid plasma-membrane-derived vesicles, enriched in tumour-associated surface antigens (MLr), occurring in the ascites fluid of a murine leukaemia (GRSL).

Extracellular membraneous vesicles of GRSL leukaemia cells were isolated from the ascites fluid bathing the cells in vivo, and from cell washes. Mammary tumour virus-induced antigens (MLr) expressed on the surface of the cells are enriched on these vesicles as compared to plasma membranes isolated from the cell homogenate. The lipid fluidity of the vesicles is much smaller than that of the plasma membranes, and the content of the pertinent lipid parameters, cholesterol and sphingomyelin, are accordingly greatly increased. The extracellular vesicles which are also enriched in sialic acid and 5'-nucleotidase are apparently derived from the plasma membrane, probably at least partly by exfoliation of selected parts or domains of the surface of living cells. An analogy between this shedding of vesicles, the formation of endocytotic vesicles and the budding of viruses is noted; all these processes select or assemble rigid lipid domains of the cell membrane. The possible participation of surface microvilli and sub-lethal autolysis in the process of shedding is discussed.

Animals↗
PubMed1976

Effect on glutaraldehyde fixation on lectin-mediated agglutination of mouse leukaemia cells.

The effect of glutaraldehyde fixation on lectin-mediated agglutination of murine leukaemia (GRSL) cells was investigated using 2 assay methods which differed in the shear forces to which the agglutinated cells were subjected. First, lectin and cells were allowed to interact under conditions in which shear forces were minimized and the degree of agglutination was evaluated microscopically by the appearance and size of the cell aggregates. This assay demonstrated that concanavalin A (con A)-, wheat germ agglutinin (WGA)- or Ricinus communis agglutinin I (RCAI)-mediated cytoagglutination was unaffected (WGA and RCAI) or somewhat enhanced (con A) by prior fixation of the cells with glutaraldehyde. Secondly, an electronic particle counter was used to measure the disappearance of single cells and concomitant appearance of cell aggregates as a function of the lectin concentration. In this assay, in which the aggregated cells are subjected to significant shear forces during dilution and cell counting, agglutination of GRSL cells by each of the 3 lectins was drastically inhibited by prior fixation of the cells with glutaraldehyde. This assay also demonstrated enhanced nonlectin-induced cell aggregation after fixation. In both cytoagglutination assays about the same lectin concentration was required for threshold agglutination of unfixed cells. Comparatively, the results of the 2 cytoagglutination assays indicate that a fraction of the lectin-mediated bonds between unfixed cells is shear resistant and that fixation of the cells either weakens these bonds or inhibits their formation. Morphologically, cells prefixed with glutaraldehyde were sperical at all lectin concentrations, with a continuous dense distribution of cell surface-bound con A, labelled directly with haemocyanin or indirectly using the peroxidase-diaminobenzidine reaction. Unfixed cells showed angular and toadstool-shaped deformations, especially at the highest lectin concentrations, the agglutinating surfaces being flattened against each other over extended areas. The distribution of con A label was continuous and dense between the apposed surfaces and discontinuous on free surfaces. In the presence of con A the free surfaces of prefixed cells exhibited more microvilli than the surfaces of non-prefixed cells. These results favour the view that fixation prevents the formation of shear-resistant, lectin-mediated bonds between cells, not by restricting the lateral mobility of lectin receptors, but by impairing the apposition of rigid cell surfaces.

Agglutination↗
PubMed1975

Quantitation of virus-induced (MLr) and normal (Thy.1.2) cell surface antigens in isolated plasma membranes and the extracellular ascites fluid of mouse leukemia cells.

Plasma membranes were isolated by two methods from mouse leukemia cells containing mammary tumor virus-induced (MLr) and normal (Thy.1.2) antigens on their surfaces. A number of chemical components, enzymic activities, and the antigenic contents were determined in subcellular fractions and found to be specifically concentrated in the plasma membrane fractions. The major part of the cellular MLr, in contrast to Thy.1.2, was present in the 105,000 X gmax supernatant of the cell homogenate. This and other results indicate an easy release of the antigen from the plasma membrane. A considerable amount of MLr was also present in the ascites fluid, partly free and partly bound, supposedly in an immune complex that allowed the isolation of three components of similar molecular weights as mammary tumor virus components. The extracellular presence of MLr may illustrate that, by shedding of antigen, the tumor may protect itself against the immunological defense of the host.

Animals↗
PubMedDate not supplied

Malignant histiocytosis and related tumors. A clinicopathologic study of 42 cases using cytological, histochemical and ultrastructural parameters.

Light and electron microscopical, immunohistochemical and clinical characteristics in 42 cases of malignant neoplasms, arising from true histiocytes, are described. These were separated in a lymphoma-like subtype, called true histiocytic lymphoma (29 patients) and a disseminated variant, called malignant histiocytosis (9 patients). In addition 4 related histiocytic tumors are discussed, including 2 tumors arising from interdigitating cells. Sinus pattern and cytologic features, especially 'window' nuclei, are emphasized as diagnostic criteria. Erythrophagocytosis was not a constant finding. Electron microscopic features, presence of acid phosphatase, acid alpha-naphthylacetate esterase, lysozyme, alpha 1-antitrypsin, alpha 1-antichymotrypsin, Ia-antigen and absence of B- and T-cell markers, were important in establishing the histiocytic nature or excluding a non-histiocytic tumor. A distinct male predominance existed (male:female = 2.5:1) with a higher relapse free period in females (p = 0.032). A high number of mitotic figures appeared to be a favourable sign, p = 0.020 and 0.019, for remission rate and relapse free period respectively. The degree of cell differentiation and the immunohistochemical pattern did not show a correlation with remission and relapse free period. Extranodal involvement and the presence of short profiles of endoplasmic reticulum were prognostically unfavourable signs. True histiocytic lymphomas showed a higher remission rate (p = 0.041) and relapse-free period (p = 0.017) than malignant histiocytosis.

Adolescent↗
PubMedDate not supplied

Sarcoma arising from interdigitating cells. Cytology and cytochemistry.

The cytologic features of a highly malignant sarcomatous tumor in a 37-year-old male, arising from interdigitating cells and localized in the mediastinum, lymph nodes and skin, are described. Cytologically this sarcoma was characterized by large cells with ill-defined, faintly basophilic cytoplasm, monocytoid or multilobulated nuclei and a reticular chromatin structure; very prominent nucleoli were seen in some of the cells. Some of the tumor cells were spindle shaped. The ultrastructurally characteristic invaginations of the cell membrane were not obvious in the cytologic smear, although the nuclear membrane showed deep, narrow, channel-like indentations. The specific ultrastructural, immunologic and cytochemical characteristics of the interdigitating cells were recognized in the tumor cells. Adenosine triphosphatase was present in the tumor cells in large amounts, while acid phosphatase, acid alpha-naphthyl acetate esterase and other enzymes were absent. The described tumor must be considered another tumor of the mononuclear phagocyte system; the proposed name is "interdigitating-cell sarcoma."

Acid Phosphatase↗