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Biomedical subjects

R Albrecht

Publications and source records attributed to R Albrecht.

At least 91 records · Page 5Linked to original sources

Pulmonary blastoma: an ultrastructural and histochemical study.

We present a unique case of pulmonary blastoma and describe its histology and ultrastructure. The stromal component exhibited bizarre multinucleated giant cells containing previously undescribed granules. These membrane-limited granules were eosinophilic, periodic acid-Schiff positive, diastase resistant, acid phosphatase and nonspecific esterase negative, immunohistologically negative for lysozyme, albumin, and gamma globulin, and often homogeneously electron dense. A similar electron-dense material accumulated in the rough endoplasmic reticulum of these stromal giant cells, suggesting that the material in the granules is synthetic. The material appeared to be a glycoprotein but was not alpha1-antitrypsin, alpha-fetoprotein, or human chorionic gonadotropin by immunohistologic techniques. These stromal cell granules differ from granules described in epithelial cells of other pulmonary blastomas but resemble granules found in some sarcomas.

Carcinoma, Squamous Cell↗

Macrophages of hypothalamic third ventricle. I. Functional characterization of supraependymal cells in situ.

Cells on the ependymal surface of hypothalamic third ventricle of hamsters exhibit surface, ultrastructural, and phagocytic features of macrophages. The object of this investigation was to identify functions that a resident phagocytic system of the ventricles of the brain may have normally. We found that supraependymal macrophages in two- to three-week-old hamsters were associated with intact and degenerating intraventricular neuronal processes, ependymal cytoplasmic blebs, and degenerating intraventricular cells. These macrophages frequently contained cellular debris within phagosomal vacuoles. In the vicinity of neuronal ganglion on the floor of the third ventricle, there were numerous structures identified as growth cones, with organelles in varying stages of alteration and degeneration. Supraependymal macrophages apparently remove cellular debris resulting from ependymal metabolic processes and from cellular and neuritic degeneration. Such activity may be part of a normal process of remodeling, involving cell growth, renewal, or cell death within the third ventricle of developing animals.

Animals↗

Macrophages of hypothalamic third ventricle. II. Immunological characterization of supraependymal cells in culture.

The question of whether hematogenous macrophages are present in the brain has remained incompletely resolved for many years. In the present study, a modified tissue culture system was employed, which enabled the isolation and visualization of cells which migrated from the surface of the hypothalamic third ventricle. Cultured cells were examined for macrophage characteristics, such as surface fine structure and cell spreading, phagocytic activity, nonspecific esterase activity, and the presence of cell surface receptors for the Fc portion of the immunoglobulin IgG. Markers of these characteristics were correlated cell by cell with light microscopy and scanning electron microscopy, utilizing both secondary and back-scattered electron imaging. Cells with all characteristic markers of the monocyte/macrophage line were identified and represent ventricular macrophages.

Animals↗

Monoclonal antibody against a membrane antigen characterizing leukemic human B-lymphocytes.

In the diagnosis of non-Hodgkin's lymphomas, the ready characterization of the neoplastic cell lineage by analysis of cell surface markers is of great importance. We present evidence for the existence of a human B-leukemia-associated antigen recognized by a complement-fixing monoclonal antibody (anti-Y 29/55). A hybridoma was produced by fusing mouse myeloma cells and splenocytes of a mouse immunized against lymphoid cells of a patient with B-cell chronic lymphocytic leukemia. Characterization of anti-Y 29/55-reactive normal and malignant leukocytes was demonstrated by cytolysis and indirect immunofluorescence. This revealed reactivity with an antigen on B-lymphoma cells (11 patients), on leukemic lymphocytes in B-cell chronic lymphocytic leukemia (13 patients), and on malignant cells in hairy-cell leukemia (two patients) but not on leukemic cells of T-cell acute lymphoblastic leukemia (one patient), on T-lymphoma cells (one patient), on cells of acute myeloblastic leukemia (four patients), or of chronic myeloid leukemia (four patients). No specific cytolysis occurred with B- and T-peripheral blood lymphocytes from (a) healthy donors (16 individuals), (b) patient with reactive lymphocytosis (one patient), (c) nonleukemic multiple myeloma (six patients), or (d) Hodgkin's disease (three patients). Surface immunoglobulin-positive, sheep RBC-negative lymphocytes isolated from human spleen (three individuals), tonsils (seven individuals), and lymph nodes (one individual), however, were recognized. It is concluded that leukemic B-cells carry a marker characteristic of nonrecirculating sessile B-lymphocytes.

Adolescent↗

[Determination of leukemic B-lymphoma cells with the monoclonal antibody anti-Y 29/55].

The monoclonal antibody anti-Y 29/55 recognizes a group specific antigen on sessile human B-lymphocytes which do not belong to the recirculating lymphocyte pool. The occurrence of this antigen in malignant NHL, with or without leukemic state, and in other leukemias has been studied. The antigen was expressed on cells of various histologic B-cell types but not on leukemic cells of ALL, T-lymphoma, AML or CML. It is concluded that in malignant B-lymphoma, B-CLL and HCL, cells appearing in blood carry a marker characteristic of virgin or activated sessile B-lymphocytes. Anti-Y 29/55 permits differentiation of such cells from normal recirculating B-cells and other leukemic cells including ALL, AML and CML. In follow-up studies this antibody may be helpful in detecting early leukemic output. B-lymphocytic leukemia may reflect a disproportion between binding sites on the lymphatic reticulum and the neoplastic cells bearing this antigen, which might be involved in binding of B-lymphocytes to the supporting lymphatic reticulum.

Antibodies, Monoclonal↗

[The diagnostic value of T- and B-rosette formation and the unspecific acid esterase in the differential diagnosis of acute and chronic leukemia].

The diagnostic significance of acid non-specific alpha-naphthyl-acetate (ANAE) and of rosette formation of leukemic cells with sheep and mouse erythrocytes was studied in 8 patients with acute myeloic leukemia (AML), in 4 patients with acute lymphatic leukemia (ALL) and in 14 patients with chronic lymphatic leukemia (CLL). ANAE showed typical diffuse cytoplasmic activity in all cases of AML. The enzyme activity was granular in both of the lymphoid malignancies, T-ALL and B-CLL, allowing differentiation from AML but not between B- and T-leukemia cells. Rosette formation with mouse erythrocytes (ME) was diagnostic in all 14 cases of CLL and superior to labeling of surface immunoglobulin (8 of 14 cases positive). ME-rosette forming myeloblasts were detected in 2 of 4 evaluated cases of AML. Rosette formation with sheep erythrocytes (SE), including cytological evaluation of rosette-forming cells, was diagnostic in all cases of ALL (= T-ALL). In 6 of 9 patients with AML, however, rosette formation with SE was observed in a few cells, including myeloblasts with Auer rods. The occurrence of blasts in myeloic leukemia carrying lymphoid cell markers is discussed in the light of recent findings, according to which lymphoblastoid cells may arise in the course of myeloic leukemia requiring antileukemic treatment different from that of AML.

Animals↗

Can whole blood be used instead of separated low density cells for examination of the mitogen response?

The response of whole blood and separated low density cells to 3 mitogenic lectins [Phytohaemagglutinin (PHA), Pokeweed mitogen (PWM) and Concanavalin (Con-A)] was tested in 133 normal individual of all ages, including cord blood. The results obtained with the two methods correlated poorly (r = 0.16 for PHA; 0.47 for PWM and 0.42 for Con-A). Thus, the two methods measure different things and results are not comparable.

Blood↗

High T cell colony numbers do not reflect immune competence.

The number of T cell colonies growing from ficoll separated PHA-stimulated peripheral blood cells was compared to 3H-thymidine uptake in 133 normal donors of all ages. Unexpectedly, the two parameters did not correlate: The tendency of growing cells to aggregate during the incubation period resulted in few, but large spherical colonies in persons who by young age and high counts for thymidine uptake were judged to have good T cell function. This clustering effect was less pronounced in old persons and those with a low PHA response; it was virtually absent in 17 of 18 patients with undoubted cellular immune deficiency early after allogeneic bone marrow transplantation. This resulted in a growth pattern consisting of a high number of small scattered colonies. The capacity of growing cells to aggregate was sensitive to sublethal irradiation. We conclude that the number of T cell colonies growing from a given cell suspension not only depends on the number of lymphocytes responding to the mitogen. It is negatively determined by the drive of growing cells to cluster. This phenomenon deserves further study, since it appears to be a parameter of cellular immune competence which is not readily recognized with 3H thymidine incorporation.

Adolescent↗

Supraependymal macrophages of third ventricle of hamster: morphological, functional and histochemical characterization in situ and in culture.

Supraependymal cells (SECs) of the young hamster's third ventricle have been examined by scanning and transmission electron microscopy. Of special interest were cells with the surface morphology and ultrastructure of macrophages, which were found in largest numbers in 12--15-day-old females and males. In the ciliated areas SECs are generally smooth and rounded; in nonciliated areas, they frequently have surface ruffles, blebs and microprocesses. SECs were frequently seen to be dividing or fusing. The macrophage-like cells are characterized by prominent Golgi zones and numerous large vacuoles, and frequently contain inclusions in their cytoplasm which resemble intraventricular cell processes, cytoplasmic protrusions from ependymal cells and cellular debris. We have demonstrated that supraependymal macrophage-like cells phagocytose latex beads injected into the ventricles of the brain. Supraependymal cells from 12-day-old hamsters were grown in tissue culture. Phagocytic, cytochemical and surface ultrastructural studies were then done sequentially on the same population of cells. These studies revealed the cells to be actively phagocytic as well as strongly esterase positive and peroxidase negative, consistent with their classification in the macrophage/monocyte category. The surface ruffles, ridges and microprocesses were also characteristic of the SECs seen in situ with scanning electron microscopy and of the macrophages cultured from the peritoneum and peripheral blood of the same hamsters. On the basis of cellular morphology, cytochemical staining characteristics and functional response to exposure to foreign particles both in situ and in cell culture, we have demonstrated that supraependymal cells of the third ventricle of the hamster are phagocytes that resemble cells of the macrophage/monocyte line. It is suggested that they constitute a resident macrophage system of the ventricles of the brain.

Animals↗

[Immune profile in patients with Hodgkin's disease in long-term remission after cytostatic chemotherapy].

13 patients in complete and prolonged remission after treatment with cytostatic chemotherapy for disseminated Hodgkin's disease have been investigated for immune competence by a total of 27 immunological parameters. 11 patients had abnormal values for lymphocyte populations, lymphocyte function and skin tests. The immune profile described is suitable for long-term evaluation of patients under immunosuppressive therapy.

Adolescent↗

Functional relationship of macrophages and basophils to the thymus gland.

Human thymus epithelium, depleted of thymocytes and macrophages by means of organ culture, was used in chemotaxis experiments with peripheral blood cells. Such cultured thymus epithelium can attract specifically macrophages and basophils. T-lymphocytes were attracted only by short-term (8 day) cultured thymus tissue which still retains some of the original macrophage population. Thymic macrophages formed rosette structures with thymocytes. In other experiments 'activated' rabbit macrophages had the capability to destroy thymocytes, whether autochthonous or allogeneic. The possible role of macrophages and basophils in thymus function is discussed.

Animals↗

Impairment of isoproterenol, H2 histamine, and prostaglandin E1 response of human granulocytes after incubation in vitro with live influenza vaccines.

The release of the lysosomal enzyme beta-glucuronidase from granulocytes follows incubation in vitro with complement-activated zymosan particles. Release of beta-glucuronidase is inhibited by isoproterenol, histamine, and prostaglandin E1. This in vitro model was used to study the effect of incubating a live, bivalent (A + B) influenza vaccine on the granulocyte response to the agonists described. After incubation in vitro with the live, bivalent influenza vaccine, there was a significantly impaired granulocyte reponse to all 3 agonists. The change in the response of polymorphonuclear leukocytes to isoproterenol was similar to an impairment in beta-adrenergic response found during respiratory infections in vivo. The viral-induced changes in the granulocyte response to isoproterenol may reflect similar alteration in other tissues, such as variable control of the airways and provide one explanation for the occurrence of airway dysfunction during respiratory infections.

Adult↗