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Biomedical subjects

M Shamoto

Publications and source records attributed to M Shamoto.

At least 19 recordsLinked to original sources
PubMed1992

Langerhans cells in the lymph node: mirror section and immunoelectron microscopic studies.

Cells immunostained with antibodies against both OKT-6 and S-100 protein were observed only in superficial and hilar lymph nodes draining tissues with predominantly squamous epithelia. In contrast, in mesenteric lymph nodes and the spleen, only S-100 protein-positive, but OKT-6-negative cells were found. We suspect that the S-100 and OKT-6-positive cells might be Langerhans cells (LC) and the S-100-positive, OKT-6-negative cells, interdigitating reticulum cells (IDC). We further postulate that the LC in superficial and hilar lymph nodes might migrate from squamous epithelia, with which contact is required for the formation of Birbeck granules.

Aged↗
PubMed1992

Human glioma-specific antigens detected by monoclonal antibodies.

Three murine monoclonal antibodies, designated GA-17, GB-4, and GC-3, were prepared by the hybridization of murine myeloma cells (NS-1) and spleen cells of BALB/c mice immunized with the crude membrane fraction of cultured human gliosarcoma cells (GI-1). Two of them (GA-17 and GB-4) reacted exclusively with the membrane of glioma cells, and the other (GC-3) reacted with the membrane of glioma cells and a T cell line (MOLT-4). Although these antibodies reacted with almost all of the gliomas, the reactions differed. GA-17 reacted equally well with all glioblastoma (17 cases) and low-grade astrocytoma (10 cases), whereas GB-4 reacted poorly with 7 cases of glioblastoma and GC-3 did not react with 7 cases of low-grade astrocytoma. The antigens, exclusively expressed on the cell surface, were analyzed by surface labeling with 125I followed by a cell lysis and immunoprecipitation with these antibodies. The findings obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that GA-17, GB-4, and GC-3 reacted with Mr 140,000-145,000, Mr 160,000, and Mr 145,000-150,000 proteins, respectively. Some evidence has been obtained indicating that these antigens are composed of the same polypeptide chain (Mr 120,000) with the carbohydrate chains being different.

Animals↗
PubMed1992

A new rat mutant with chronic conjugated hyperbilirubinemia and renal glomerular lesions.

A new mutant strain of inbred Sprague Dawley rats with autosomal recessive hyperbilirubinuria, were studied by biochemical, histologic, and ultrastructural methods. The plasma bilirubin concentration in the homozygote was significantly higher than that of the heterozygote, and about 80% of the bilirubin was conjugated. Plasma BSP and ICG clearance were both severely delayed in the homozygote. Plasma BSP elimination kinetics suggested that the pathophysiologic defect was not hepatic uptake or storage but rather in secretion into bile. Histopathology of the liver demonstrated brown pigment in the hepatocytes that appeared to be lipofuscin. The electron microscopic features of the hepatic pigment resembled those of the Dubin-Johnson syndrome. Homozygote histopathology also revealed glomerular lesions with mesangial expansion and proliferation in the kidneys. Immunohistologic studies disclosed mesangial granular deposition of IgG, IgA, and to a lesser degree, IgM and C3. These renal changes resembled those of IgA nephropathy. The spontaneous hyperbilirubinuric rat (EHBR) may be a useful animal model for studying constitutive conjugated hyperbilirubinemia, bilirubin metabolism, cholestasis, and glomerulonephropathy subsequent to hepatic dysfunction.

Animals↗
PubMed1991

Ascorbic acid and adriamycin toxicity.

Adriamycin (ADR) is effective against a wide range of human neoplasms. However, its clinical use is compromised by serious cardiac toxicity, possibly through induction of peroxidation in cardiac lipids. Ascorbic acid, a potent antioxidant, was examined for effect in reducing ADR toxicity in mice and guinea pigs. Ascorbic acid had no effect on the antitumor activity of ADR in mice inoculated with leukemia L1210 or Ehrlich ascites carcinoma, but it significantly prolonged the life of animals treated with ADR. ADR elevated lipid peroxide levels in mouse heart, and ascorbic acid prevented the elevation. The significant prevention of ADR-induced cardiomyopathy in guinea pigs by ascorbic acid was proved by electron microscopy. Ascorbic acid and the derivatives may delay general toxicity of ADR and also prevent the cardiac toxicity. The results also suggest the clinical efficacy of the combined treatment of ADR and ascorbic acid or the derivatives.

Animals↗
PubMed1988

Cytogenetic characterization of a T-cell line, ATN-1, derived from adult T-cell leukemia cells.

A T-cell line, ATN-1, was established by culturing peripheral blood mononuclear cells derived from a patient with adult T-cell leukemia/lymphoma (ATL/L). Identities of the patterns of chromosomal abnormalities, cell surface phenotypes, morphologic findings, rearrangement patterns of T-cell receptor beta chain gene, and an integration site of human T-cell leukemia virus I proviral genome indicated that ATN-1 was derived from original leukemic cells. Both ATN-1 and the original leukemic cells showed a variety of patterns of chromosomal abnormalities that include 3q-, 6q-, rearrangements involving 2q31, 7q11.2, 8q11, 8q24, 19p13.3, and also 14q11 and 14q32, where genes for the T-cell receptor alpha chain and the immunoglobulin heavy chain are located. Availability of a genuine ATL/L cell line with these chromosomal abnormalities may greatly facilitate the biologic analysis of ATL/L.

Antibodies, Monoclonal↗
PubMed1987

A monoclonal antibody detecting a novel antigen expressed in the HTLV-I-infected cells.

A monoclonal antibody, FTF 148, was prepared by hybridizing murine myelomal cells (NS-1) and spleen cells of BALB/c mice immunized with cultured cells derived from an adult T cell leukemia (ATL) patient (KUT-2 cells). This monoclonal antibody reacted with all of the human T cell leukemia virus I (HTLV-I)-infected cell lines tested but did not react with other T cell lines derived from acute lymphocytic leukemia, Epstein-Barr virus-transformed B cell lines, or an erythroleukemic cell line. This monoclonal antibody was not directed to viral antigens because it reacted equally well with almost all KUT-2 and MT-1 cells, only 1% to 3% of which were ATL-associated antigen-positive. In contrast to interleukin 2 receptors expressed on both ATL cells and normal phytohemagglutinin-stimulated blasts, this antigen was not expressed on the latter cells. The antigen, mainly expressed on the cell membrane, was analyzed by metabolic labeling with 3H-leucine and surface labeling with 125I followed by cell lysis and immunoprecipitation with the FTF 148 antibody. The findings obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that p50 and p74 proteins were specifically precipitated and the antigen was also different from the product of the Xs gene of HTLV-I.

Antibodies, Monoclonal↗
PubMed1986

Hepatoid adenocarcinomas of the stomach. An analysis of seven cases.

Hepatoid adenocarcinomas of the stomach are gastric carcinomas with both adenocarcinomatous and hepatocellular differentiations. They usually produce large amounts of alpha-fetoprotein (AFP) with a Concanavalin A-binding property of hepatic type. In this study, these carcinomas occurred in older persons, with the antrum being a common site. Observed grossly, growth of the tumors was nodular and massive. Prognosis was poor because of frequent liver metastases. In the cytoplasms of tumor cells, various serum proteins were identified, including AFP, alpha-1 antitrypsin (AAT), alpha-1 antichymotrypsin (ACT), albumin, and prealbumin. Localizations of ferritin, prothrombin, and transferrin were demonstrated with less frequency. Adenocarcinomatous foci were composed of well-differentiated, intestinal-type epithelial cells and often contained carcinoembryonic antigen. These adenocarcinomatous and hepatoid areas were often intermingled with each other. There were extensive venous involvements by tumor cells. The poor prognosis of the tumors may be attributed to these involvements as well as to production of AFP and presence of AAT/ACT, which have immunosuppressive and protease-inhibitory properties, respectively.

Adenocarcinoma↗
PubMed1986

The effect of phototherapies on cutaneous lesions of histiocytosis X in the elderly.

The effect of therapeutic ultraviolet light (UV) radiation on the skin lesions of histiocytosis X (HX) was studied in two old patients. Histiocytosis X cells in the biopsy specimens were strongly reactive with OKT-6, OK-Ia1, an anti-S-100 protein antibody, and were weakly stained with Leu-3a. Some HX cells outgrown from the explants bore immunoglobulin G receptors (Fc-IgG) and C3 receptors. In accordance with clinical improvement after repeated topical 8-methoxypsolaren (8-MOP) plus UV-A (PUVA) or UV-B radiation, the density of infiltrating HX cells gradually was decreased. The PUVA therapy seemed to be more effective than UV-B radiation in our treatment schedule. Even after repeated phototherapies, however, the reactivity of surface and cytoplasmic antigens related to OKT-6, OK-Ia1, and S-100 protein in the remaining HX cells were the same as in untreated HX cells. Although the exact mechanism remains obscure, satisfactory therapeutic results were obtained in response to the phototherapies. New skin lesions eventually recurred after cessation of the treatments, but such eruptions resolved when additional PUVA was resumed. These studies confirm that HX cells share a battery of cytologic characteristics with epidermal Langerhans' cells (LC) and that repeated phototherapies provide a beneficial effect for skin lesions of HX without adverse reactions.

Aged↗
PubMed1985

Immunoelectron-microscopic localization of Tac antigen in adult T-cell leukemia/lymphoma.

The localization of Tac antigen in adult T-cell leukemia-associated antigen (ATLA)-positive lymphomas was studied ultrastructurally with the use of the immunoperoxidase technique. The antigen was observed on the plasma membranes of a portion of the characteristic cells with convoluted nuclei and a majority of the cells with less irregular nuclei, which were larger than the former. In addition, the cisternae of the rough endoplasmic reticulum, perinuclear cisternae, and Golgi cisternae of the latter cells were also positively stained with anti-Tac antibody. It is thought that the positive reaction of the plasma membranes may correspond to interleukin 2 (IL 2) receptors, the cytoplasmic and perinuclear reaction sites may well correspond to the precursor of IL 2 receptors, and Tac antigen may be produced in the cytoplasm of the ATLA-positive lymphoma cells.

Antigens, Surface↗
PubMed1979

Intracytoplasmic type A virus-like particles in angioimmunoblastic lymphadenopathy.

Virus-like particles which seemed to be oncogenic have not been observed clinically in human neoplasms. However, we found some virus-like particles in the cytoplasm of a few proliferating cells in the lymph nodes of one patient with angioimmunoblastic lymphadenopathy. These were very similar to intracytoplasmic type A particles seen in the Mazon-Pfizer monkey virus and a mammary tumor virus in a mouse.

Adult↗
PubMed1979

Some problems on the histopathological diagnosis of non-Hodgkin's malignant lymphoma -- a proposal of a new type.

A new classification for non-Hodgkin's malignant lymphoma is proposed as the one suited for the Lymphomas in Japan, which is to provide a new subtype "pleomorphic" for those more or less rapid-growing lymphomas of peripheral T-cell nature, along with another subtype lymphoblastic, after Nathwani et al. for those of central T-cell nature. The proposal is based on the result of the investigation by the Study Group for Histopathological Diagnosis on Malignant Lymphoma that (1) the presence of a significant number of T-cell lymphomas with peculiar "pleomorphism" is responsible for the very low reproducibility rate of histopathological diagnosis on the diffuse, mixed L&H type of Rappaport classification, and (2) the relative incidence of lymphoms as peripheral T-cell nature including the so-called adult T-cell leukemia is much higher in Japan than in the Western countries.

B-Lymphocytes↗
PubMed1978

Intranuclear cytoplasmic organelles in hematopoietic diseases.

Mitochondria, rough endoplasmic reticulum, Golgi apparatus and other cytoplasmic organelles were found within the nuclei, not in 'nuclear pseudo-inclusions', of some cells in several hematopoietic disorders. Mitoses were fairly often observed in the atypical cells of these cases. We suggest that these intranuclear cytoplasmic organelles may be trapped in the nucleus during an abnormal mitosis.

Bone Neoplasms↗
PubMed1977

Malignant histiocytosis with chronic course. Ultrastructural and ultrastructural cytochemical studies.

Four cases of malignant histiocytosis with leukemic manifestations and chronic course were reported. Light microscopic, ultrastructural and ultrastructural cytochemical details of these atypical cells were demonstrated. Ultrastructurally these cells resembled hairy cells most closely among the known varieties of leukemic cells. However, ribosome-lamella complexes were not found and some atypical cells had a few short cytoplasmic projections. In addition, tartrate-resistant acid phosphatase was absent from these cells. We speculate that this leukemic reticuloendotheliosis with a chronic course seen in Japan seems to be analogous to malignant histiocytosis with massive splenomegaly reported by Vardiman et al.

Acid Phosphatase↗