Biomedical subjects

M L Hansmann

Publications and source records attributed to M L Hansmann.

192 records · Page 11Linked to original sources

PubMed1985

HTLV-positive and -negative T-cell lymphomas. Morphological and immunohistochemical differences between European and HTLV-positive Japanese T-cell lymphomas.

A total of 56 cases of malignant lymphoma presumed to be of peripheral T-cell origin were investigated with regard to histological and immunohistochemical features. The goal of the study was to determine whether virus-associated T-cell lymphomas can be morphologically or immunohistochemically distinguished from presumably virus-negative T-cell lymphomas. The cases came from endemic and non-endemic regions of Japan, the United Kingdom (including 4 Caribbean cases) and the Federal Republic of Germany. Sera of all Japanese and Caribbean patients and 8 German patients were tested for antibodies to adult T-cell leukaemia virus-associated antigen HTLV-A. In all cases sections were examined blind by 5 well-trained histopathologists. In most cases cryostat sections could be prepared from fresh tissue specimens and stained with a large panel of monoclonal antibodies. All HTLV-A-positive cases were morphologically classifiable as the pleomorphic type of T-cell lymphoma. Approximately 70% of the tested cases of pleomorphic T-cell lymphoma, however, showed a positive serum reaction for HTLV-A. All other types of peripheral T-cell lymphoma (T-immunoblastic lymphoma, chronic lymphocytic leukaemia of T type, T-zone lymphoma, "AILD type" and lymphoepithelioid cell lymphoma) were HTLV-A-negative and mostly observed in European patients. Thus virus-associated T-cell lymphomas appear to be invariably of the pleomorphic type; but pleomorphism is not specific to HTLV-A-positive cases. This was also evident from the results of an experiment in which 2 Japanese histopathologists attempted to recognize HTLV-A positivity in a blind study of pleomorphic T-cell lymphomas. A maximum of about 80% of cases were correctly identified, with about 10% false-positive diagnoses (in HTLV-A-negative or presumably negative cases) and 10% false-negative diagnoses. The immunohistochemical analysis revealed not only many common features but also 2 distinct differences between HTLV-A-positive and -negative T-cell lymphomas. All but one of the HTLV-A-positive cases showed reactivity with anti-Tac and all cases in the virus-positive group were negative for TU14. All other cases were Tac-negative and approximately 65% of these cases exhibited reactivity with TU14. Preliminary cytogenetic observations suggest that there are also differences in specific chromosome aberrations.

Antibodies, Monoclonal↗

PubMed1985

Soft tissue sarcoma as second malignant lesion after therapy for Hodgkin's disease. Report of two cases and review of the literature.

Two cases of soft tissue sarcoma following treatment of nodular sclerosing Hodgkin's disease are described. One patient developed a malignant schwannoma after radiotherapy, the other was diagnosed as having a malignant fibrous histiocytoma after treatment with radiation and chemotherapy. Both secondary malignancies arose within the irradiated field after a latent period ranging from 9.5 years in the first to 21 years in the second case. A review of the pertinent literature is given and previous reports of malignant tumors and leukemias following therapy for Hodgkin's disease are summarized.

Adult↗

PubMed1985

The blood microvasculature in T-cell lymphomas. A morphological, ultrastructural and immunohistochemical study.

The microvasculature of lymph nodes of 55 cases of T-cell lymphoma was studied by light microscopy, immunohistochemistry and electron microscopy. A modified peroxidase-antiperoxidase (PAP) method was used for staining paraffin sections with lectin I of Ulex europaeus (UEA-I), which is a specific marker for vascular endothelial cells. The T-cell nature of each case was proven by immunohistochemistry, including immunoperoxidase staining of frozen sections with monoclonal T-cell antibodies. The cases were subclassified according to previously established criteria, but with the addition of a separate group showing a high content of clear cells. For the purpose of the present study, the small blood vessels were separated into two main variants, viz.: high endothelial venules (HEV) and all other types of vessels with flat endothelium (SVFE). The development of each of these variants and the extent of lymphocyte migration through the vascular wall were assessed semiquantitatively. The findings suggest that the blood microvasculature, as a whole, is similar in all types of T-cell lymphoma. There were distinct differences, however, in the development of the two main categories of small vessels between the various types. Chronic lymphocytic leukaemia of T-type (T-CLL) and Sézary's syndrome were poor in SVFE and rich in HEV, and there was considerable lymphocyte traffic through the latter. In contrast, T-immunoblastic and especially T-lymphoblastic lymphocyte traffic. The appearance of the microvasculature varied markedly in the various subtypes of "pleomorphic T-cell lymphoma". In the small cell subtype HEV predominated and SVFE represented only a small or moderate fraction of the microvasculature. As the size of the neoplastic lymphoid cells increased towards the medium-sized and large cell subtype, there was a decrease in the number of HEV and an increase in the number of SVFE accompanied by a decrease in lymphocyte migration. In T-cell lymphoma of the clear cell type the microvasculature showed features between those of T-CLL and the small cell subtype of pleomorphic T-cell lymphoma. Electron microscopy confirmed the light microscopic findings and revealed many similarities in vascular changes between "pleomorphic T-cell lymphomas" and lymphogranulomatosis X.

Histocytochemistry↗

PubMed1984

Clinical features of nodular paragranuloma (Hodgkin's disease, lymphocyte predominance type, nodular).

Clinical aspects of 145 cases of nodular paragranuloma (nodular subtype of lymphocyte predominance type of Hodgkin's disease) were investigated. There was a marked male predominance, and the age curve showed a peak in the 4th decade. In a majority of cases lymphadenopathy developed within 1 year. General (B) symptoms were observed in only 15 patients. The most frequent sites of primary involvement were cervical, axillary, and inguinal lymph nodes. Other organs were rarely involved. At the time of diagnosis 50% of patients were in stage I, 21% in stage II, 22% in stage III, and 7% in stage IV. The prognosis was usually favorable or very favorable and depended on the stage of disease at diagnosis and on the age of the patient. Patients with stage I or III disease without splenic involvement had about the same probability of survival as the normal population. Stage III patients with splenic involvement had a lower probability of survival. The prognosis for stage II was also less favorable. Patients in stage IV had the lowest probability of survival. Closer analysis of the ten stage IV cases revealed two groups with different outcomes. Four cases showed progressive disease that did not respond to treatment and led to death within 12 months. The second, more favorable form (6 patients) responded well to chemotherapy. Nine patients in stage I who were not treated after lymph node biopsy were free of disease even after periods of up to 14 years. A total of 52 patients had one or more relapses. The recurrent tumors developed locally in a majority of cases. There was transformation of nodular paragranuloma into another subtype of Hodgkin's disease in only four cases. Five cases showed transformation into large-cell tumors that resembled immunoblastic lymphoma and require further immunological study.

Adolescent↗

PubMed1984

Immunoelectron microscopic demonstration of tissue antigens with monoclonal antibodies.

Two methods of demonstrating tissue antigens by ultrastructural enzyme immunohistochemistry were tested. The monoclonal antibodies Ki-M1 and Ki-M4 were chosen for testing the methods because Ki-M1 identifies a relatively stable, and Ki-M4 a very unstable antigen. The two antibodies react selectively with human macrophages and interdigitating reticulum cells or dendritic reticulum cells of lymphoid follicles. The Ki-M1 reaction product is confined to the surface membrane. Ki-M4 reactivity is located on the surface membrane and, less often and to a lesser extent, in the cytoplasm. The technical prerequisites for reliable conservation of the antigens identified by these two antibodies were standardized. The results indicated that prior fixation in 4% paraformaldehyde is preferable for optimum preservation of stable antigens. Application of the primary antibody prior to fixation was found to be the best procedure for demonstrating unstable antigens, although nonspecific reactions were seen more often with this method.

Antibodies, Monoclonal↗

PubMed1984

Immunohistochemical procedures: applications and problems.

The introduction of immunohistochemical methods into pathological diagnostics has opened new possibilities for combining the specificity of immunological methods with the selectivity of morphological techniques. This considerable expansion of diagnostic possibilities has occurred since the introduction of monoclonal antibodies. The basic conditions of immunohistochemical reactions (fixation, embedding), fundamental differences between the use of monoclonal antibodies and that of polyclonal antisera and possibilities for increasing the sensitivity of diagnoses are discussed and illustrated by practical examples.

Antibodies↗

PubMed1984

Monocyte/macrophage-specific monoclonal antibody Ki-M1 recognizes interdigitating reticulum cells.

A monoclonal antibody, Ki-M1, was produced, and its immunoreactivity was tested by light and electron-microscopic immunohistochemistry. Ki-M1 was found to react with monocytes, cells of the mononuclear phagocyte system (MPS), interdigitating reticulum cells (IDC), and the so-called indeterminate dendritic cells of lymphoid tissue. No reactivity was seen in other human tissues or other hematopoietic cells, including granulocytes and cells of the unstimulated promyelocyte cell line HL-60. Thus, Ki-M1 is the first of the monoclonal antibodies to MPS cells to react with both human IDC and MPS cells. This suggests that IDC and MPS cells may have a common cytogenesis.

Animals↗

PubMed1983

Monoclonal antibody Ki-M4 specifically recognizes human dendritic reticulum cells (follicular dendritic cells) and their possible precursor in blood.

Ki-M4, a new IgG3 monoclonal antibody, selectively recognizes dendritic reticulum cells (DRC; follicular dendritic cells) in all human lymphatic organs, as tested by the immunoperoxidase method on the light and electron microscopic level. This antibody was raised against separated lysosomes of the 12-0-tetradecanoyl phorbol-13-acetate (TPA) stimulated permanent cell line, U-937, derived from a human histiocytic lymphoma. No cross-reactivity was encountered in epithelial and mesenchymal cells, including macrophages and other cells detectable in bronchial and peritoneal lavages. In the nonadherent fraction of the mononuclear blood cells collected from the interphase of a Ficoll-Urografin gradient (density = 1.077 g/ml), 0.1 per million of the cells hitherto not classified as monocytes or lymphocytes showed a strong reaction. All other separated blood cell types were devoid of any reactivity. The observation that DRC share a highly restricted, and thus specific, antigen with a small but distinct subpopulation of mononuclear leukocytes implies their blood derivation.

Antibodies, Monoclonal↗

PubMed1983

Peroxidase-positive mononuclear leukocytes as possible precursors of human dendritic reticulum cells.

In this report, we provide evidence that suggests the dendritic reticulum cells (DRC) occurring in germinal centers of lymphatic follicles originate from a distinct endogenous peroxidase-positive mononuclear blood cell subset. The new monoclonal antibody Ki-M4 showed a highly restricted reactivity, tested by immune histochemistry, being confined to DRC, lining cells of lymph node sinuses, and to 0.001% of nonadherent mononuclear blood cells separated at a density of 1.077 g/ml; the latter exhibited endogenous peroxidase activity in cytoplasmic granules. Such granules being specific for myelomonocytic cells implies that DRC may derive from a committed nonadherent subpopulation of this cell line, which in turn originates from bone marrow. The Ki-M4-reactive antigen was found to be destroyed by the majority of fixatives and to resist 4% paraformaldehyde for 10 min and cold acetone for 30 sec. In cell suspensions from human tonsils, Ki-M4 showed strong reactivity with the outer surface of DRC plasma membrane. This observation demonstrates the possibility of using Ki-M4 to separate DRC from cell suspensions in functional tests.

Animals↗

PubMed1982

The lacunar cells and its relationship to interdigitating reticulum cells.

Lacunar cells, which are characteristic of the nodular sclerosis type of Hodgkin's disease, were investigated by light and electron microscopy and by enzyme cytochemical and immunohistochemical methods. Characteristic ultrastructural features of the lacunar cells were its size, its multilobated nucleus, and the pale cytoplasm containing only a few organelles. These features distinguish the lacunar cell from typical Sternberg-Reed and Hodgkin cells. Enzyme cytochemically, lacunar cells were weakly positive for acid phosphatase and non-specific esterase. the reaction product was distributed either diffusely or more focally in the cytoplasm. By immunostaining, kappa, lambda, and IgG could be detected in some lacunar cells. The immunostaining pattern was bitypic, which might have resulted from non-specific uptake. All the results of the present study indicate that lacunar cells are non-lymphoid cells. When lacunar cells were compared with cells of normal lymphoid tissue, their ultrastructure was found to be very similar to that of interdigitating reticulum cells. Both cell types showed a bizzarrely shaped nucleus and an electron-transparent cytoplasm with only some vesicles and tubules. Furthermore, lacunar cells and interdigitating reticulum cells exhibited a similar reaction pattern of acid phosphatase and non-specific esterase. Thus, from a cytologic and enzyme cytochemical point of view, a direct relationship between the two cell types is very likely.

Acid Phosphatase↗

PubMed1982

Ultrastructural localization of human complement C3b receptors in the human kidney as determined by immunoperoxidase staining with the monoclonal antibody C3RTo5.

The precise localization of human complement C3b receptors in human kidneys was investigated by means of indirect immunoperoxidase staining of frozen kidney sections with the monoclonal antibody C3RT05, which is specific for human C3b receptors. Transmission electron microscopy indicated that C3b receptors are located on the entire cell membrane of the visceral epithelial cells of the glomeruli.

Antibodies, Monoclonal↗

PubMed1981

Electron-microscopic aspects of Hodgkin's disease.

Lymph nodes from patients with Hodgkin's disease of the nodular sclerosis or mixed cellularity type were examined by electron microscopy to classify all the cells that occur in these types of lymphoma. Most of the cells showed morphological features that were the same, or nearly the same, as those of cells of normal lymphoid tissue. These included typical interdigitating reticulum cells (IDC), histiocytic reticulum cells, so-called dark reticulum cells, and sinus macrophages. There were also small and medium-sized lymphocytes, immunoblasts, plasma cells, and plasma cell precursors resembling those seen in non-specific lymphadenitis. Germinal center cells, on the other hand, were present in negligible numbers. Special attention was paid to Hodgkin's (H) and Sternberg-Reed (SR) cells. This group of cells proved to be heterogeneous. The only common features were a large cell size, large nuclei, and a prominent nucleolus. Some of the H and SR cells resembled immunoblasts of normal lymphoid tissue. The cytoplasm of these cells contained numerous polyribosomes, and their heterochromatin was coarsely condensed at the nuclear membrane. Other H and SR cells were more similar to histiocytic cells or reticulum cells because of the large number of cell organelles (e.g., lysosome-like granules) and diffuse heterochromatin. Finally, cases of the nodular sclerosis type of Hodgkin's diseases showed another cell type with some resemblance to IDC. The cells of this type are called lacunar cells because of their special light-microscopic appearance.

Histiocytes↗