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Biomedical subjects

A Nagayama

Publications and source records attributed to A Nagayama.

At least 37 records · Page 2Linked to original sources
PubMed1988

Persistent infection with herpes simplex virus type 1 in an Ia antigen-positive murine macrophage cell line.

The interaction of herpes simplex virus type 1 (HSV-1) with murine macrophage cell lines was examined. The cell lines appeared to be moderately permissive for HSV-1 replication, though the yield of the virus was limited compared with that in Vero cells. Furthermore, the murine macrophage cell line SL-1, bearing Ia antigen, was persistently infected with HSV-1 for over one year, and was designated SL-1/KOS. Persistent infection could not be established in an Ia antigen-negative macrophage cell line, SL-4. In the SL-1/KOS culture, there was a small number of infected cells as revealed by infectious center assay. Treatment with monoclonal antibody against HSV-1 cured the persistent infection. Therefore maintenance of the persistent infection is considered to be due to a carrier culture consisting of a minority of infected cells and a majority of uninfected cells. In the SL-1/KOS cultures a low level of interferon (IFN) was found. When a large amount of exogenous recombinant murine IFN-beta (10(5)-10(6) international units/ml) was added to the culture, virus production diminished to undetectable levels. These results suggest that IFN plays an important role in the maintenance of persistent infection. In long-term persistently infected cultures, syncytium formation appeared and the virus from such cultures had a different DNA structure from that of the virus originally used for infection as revealed by restriction endonuclease analysis.

Animals↗
PubMed1988

Acquisition of repertoires of suppressor T cells under the influence of macrophages.

Acquisition of repertoires and genetic restriction specificities of suppressor T cells (Ts) and their factors were studied by using full allogeneic radiation bone marrow chimera and H-2 congenic pairs, B10.A(3R) and B10.A(5R), which received conventional or cloned macrophages by cell transfer. Suppressor T-cell factor (TsF) from C3H----C57BL/6 or C57BL/6----C3H chimera suppressed only donor but not host-type responses of either C3H or C57BL/6, in an antigen-specific fashion. However, if chimera mice were given conventional or cloned macrophages of the host type, the chimera TsF in turn suppressed both the responses of C3H and C57BL/6 mice but not those of the third party, BALB/c, indicating that macrophages are responsible for the acquisition of host restriction specificity. Similarly, B10.A(5R) mice developed I-Jb restricted Ts or TsF when the B10.A(3R) macrophage cell line was injected at the time of antigen priming. The reverse was also true. B10.A(3R) mice did generate I-Jk restricted Ts when they received the B10.A(5R) macrophage cell line. Thus, the results clearly demonstrated that B10.A(3R) or B10.A(5R) mice potentially possessed their ability to express both I-Jk and I-Jb determinants and that repertoires and genetic restriction specificity of Ts and their TsF were acquired at a macrophage level at the time of antigen-priming.

Animals↗
PubMed1987

Properties of colony-stimulating factors produced by macrophage cell lines and hybrid cells.

Colony-stimulating factors (CSFs) produced by two simian virus 40(SV40) transformed macrophage cell lines (BAM1 and BAM3), and three hybrids (HM3-11, HM3-12, and HM3-14) derived from fusion between BAM3 and a Chinese hamster cell line (hs222-16) were examined. HM3-11 and HM3-14 produce two molecular species of CSF, which are not found in the conditioned media from cultures of BAM1 and BAM3 or lipopolysaccharide (LPS), phorbolmyristate-acetate (PMA), and zymosan-stimulated BAM3. HM3-12, which is classified into another group in terms of CSF secretion, does not produce these two CSFs. On the basis of various criteria, one of these CSF species (peak 1-CSF) was characterized as a macrophage-colony-stimulating factor (M-CSF). The other CSF (peak 2-CSF) induced a group of bone marrow cells in granulocytes and macrophages as well as growth of a mast cell line, IC2. This CSF has an apparent molecular weight of 18,000, estimated by SDS-polyacrylamide gel electrophoresis. Unlike interleukin 3 (IL3) from WEHI-3 cells, the growth factor activity of peak 2-CSF binds to DEAE-Sephacel. Thus, peak 2-CSF is similar to a granulocyte-macrophage colony-stimulating factor (GM-CSF) rather than to IL3. The anti L cell CSF serum does not inhibit the CSF activity in Chinese hamster fibroblast conditioned medium, and the IC2 cells do not respond to Chinese hamster lung conditioned medium (CHLCM), suggesting that peak 1- and peak 2-CSF are of mouse origin.

Animals↗
PubMed1986

I-J-positive cloned macrophages as accessory cells for the induction of suppressor T cells in vitro.

I-A+/I-J+ cloned macrophages, SL-1, played the role of APC in the in vitro induction of Ts against DTH to BCG. By treating SL-1 cells with various antibodies, it was shown that I-J antigens on SL-1 cells are essential for Ts induction, but not for the effector cell induction for DTH. Ia-negative cloned macrophages, SL-4, did not show any APC activity either in suppressor or effector cell induction. The precursors of the Ts were also I-J-positive, and I-J restriction resided between T cells and macrophages in the Ts induction. Thus, it is suggested that the pre-Ts recognizes the antigenic determinants of BCG presented on the APC in association with the I-J antigen and differentiates into the Ts. This pathway seems analogous to that of helper or effector T induction, where the antigenic determinant is recognized by a T cell in association with the I-A antigen on APC.

Animals↗
PubMed1986

Enhanced bactericidal action of mouse macrophages by subinhibitory concentrations of monobactams.

The effects of sub-minimum inhibitory concentrations (sub-MICs) of monobactams (aztreonam and AMA1080) on the host-parasite relationship were studied in an in vitro system using an established mouse macrophage cell line. The presence of sub-MICs aztreonam or AMA1080 enhanced significantly the macrophage bactericidal activity against Escherichia coli S615, Pseudomonas aeruginosa K1, Klebsiella pneumoniae 12 and Serratia marcescens US5. Even four times the MIC of monobactams had no direct effect on macrophages. A synergistic bactericidal effect against E. coli was also observed with sub-MICs of monobactams and lysozyme or macrophage lysate. Furthermore, E. coli treated with sub-MICs of aztreonam was more sensitive to two bactericidal macrophage products, hydrogen peroxide and superoxide anion. These results suggest that the effects of monobactams are exerted on bacteria and not on macrophages; sub-inhibitory levels of monobactams may alter the bacterial cell rendering it more susceptible to bactericidal substances released by macrophages, thus favouring phagocytosis and killing by macrophages. Electron microscopic observations support these conclusions. This study provides evidence that monobactams at sub-MICs may work in partnership with host defenses against Gram-negative bacterial infections.

Animals↗
PubMed1985

Accessory cell function of a lined macrophage in the induction of suppressor T cells in vitro.

Antigen-specific Ts against DTH to BCG were induced in vitro by culturing the splenic T cells of C3H/He mice together with the lined macrophage, SL-1, pulsed with PPD. The suppressor activity was determined by the suppression of DTH in CY-treated syngeneic recipients which had received the cultured cells before BCG sensitization. SL-1 cells express I-A and I-J antigens on the surface, while SL-4 cells, which originated in the same mouse strain as SL-1, do not express any Ia antigens. When I-A antigens on SL-1 were blocked by anti-I-A antibody without complement before PPD-pulsing, the induction of Ts was rather enhanced. When I-J antigens on SL-1 were blocked by anti-I-J alloantiserum, no Ts were induced. Instead, these I-J-blocked and PPD-pulsed SL-1 cells induced effector cells of DTH in vitro. Ia-negative lined macrophage SL-4 cells did not show any activity either in suppressor or in effector cell induction. From these results, we propose a model for the immune modulation led by APC.

Animals↗
PubMed1985

[A case of remission of metastatic gastric cancer lesions in the chest and abdominal wall by 5'-DFUR administration].

52-year-old female was weakened and bed-ridden by metastasis of gastric cancer to the chest and abdominal wall, and peritonitis carcinomatosa 2 years after gastrectomy. One week after administration of 5'-DFUR, 1200 mg/d, p.o., a clinical effect was seen. In 3 weeks metastatic lesions had diminished in size, ascites had decreased and the patient had regained her appetite and put on weight. She recovered sufficiently to be able to do some daily work. Pathological degeneration and necrosis of cancer cells were observed. Although she died 8 months after remission, 5'-DFUR was effective in improving her condition and prolonging her life.

Abdominal Muscles↗
PubMed1983

Cell hybrids between SV40-transformed macrophage cell lines and a Chinese hamster cell line: growth responsiveness and induction of colony-stimulating factor.

Three cell lines from resident macrophages of BALB/c mice and four from activated macrophages of the same strain were isolated by infection with simian virus 40 (SV40). A majority of these cells showed dependency on L cell-conditioned medium (LCM), which is necessary for proliferation of normal macrophages in vitro. Somatic cell hybridization was applied in the study of macrophage growth responsiveness. A macrophage cell line (BR15) with strict dependency on LCM for growth was fused to a Chinese hamster cell line (hs222-16); it was found that dependency on LCM was a dominant trait in the hybrids. Following fusion of a macrophage cell line (BAM3) which grew without LCM to hs222-16, a large number of colonies appeared in the selection medium containing LCM. Four hybrids not requiring LCM for growth were selected in an LCM-free culture, and their hybrid properties were examined. Three out of the four hybrids secreted colony-stimulating factor (CSF) constitutively, whereas the fourth secreted no CSF. The level of acid phosphatase activity in the hybrids was higher than in the parent cells. Two peaks of CSF activity were observed after gel filtration chromatography of conditioned medium: One was eluted at molecular weight of 36,000 and the other at 17,000.

Acid Phosphatase↗
PubMed1983

Immunocytochemistry of the Microtubules of fat-laden cells. Brown fat cells and adrenocortical cells in primary monolayer culture.

Cytoplasmic microtubules of fat-laden cells containing fine lipid droplets, such as brown fat cells and adrenocortical cells, were studied in relation to the metabolism of intracellular lipid. In these cells, the amount and distribution of lipid droplets reflect the state of inherent cellular function. Materials used were primary monolayer culture of fetal rat brown fat cells and that of bovine adrenocortical cells. The method was the immunocytochemistry with anti-tubulin antibody. When brown fat cells were being lipolyzed or the steroidogenesis of adrenocortical cells were being stimulated, the cytoplasmic microtubules in the cells were organized in a radial pattern in response to the behavior of the lipid droplets. It is assumed that the microtubules were in the regulation of cellular function in terms of the metabolism of lipid droplets in these cells. We have devised, in the course of the current study, a double fluorescence technique as an observational method whereby microtubules were observed immunocytochemically and lipid droplets by a secondary fluorescence with phosphine E staining.

Adipose Tissue, Brown↗
PubMed1983

[Clinical study on preoperative chemotherapy of primary breast cancer. 2--A comparative study of CPA + FT-207 (5-FUDS) and CPA + FT-207 (5-FUDS) + MMC].

In 41 cases of primary breast cancer preoperative treatment was performed using 2 methods consisting CPA + FT-207 (5-FUDS) (for Group I) and CPA + FT-207 (5-FUDS) + MMC (for Group II) to determine clinical and histological efficacies. A daily dose of each anticancer drug was: CPA 50-200 mg, FT-207 200-600 mg, and 5-FUDS 200 mg orally, and MMC 4-20 mg intravenously. The mean total doses were 1.8 g, 6.3 g, 3.4 g and 26.3 mg, respectively. Reduction in tumor size was obtained in 11 cases (37.9%) in Group I and 6 cases (50.0%) in Group II. According to Ohboshi's criteria, histological efficacy as defined over Grade II a was seen in 5 cases (17.2%) in Group I and 6 cases (50.0%) in Group II, while the efficacy classified as Grade III was not seen in any of the cases. Although the clinical effect was not always consistent with the histological effect, there was a tendency of agreement between them in Group II. As to the dosages of anticancer drugs, more effective cases were seen when dosages of more than 25 mg/kg of CPA, 80 mg/kg of FT-207 (5-FUDS) or 0.5 mg/kg of MMC were used. Reduction in tumor size began to appear at 2 to 3 weeks after the initiation of treatment.

Adult↗
PubMed1979

Diagonal abdominothoracic incision as an approach to carcinoma of the cardia and upper gastric region.

An operative technique consisting of a diagonal epigastric incision extending to the left chest wall and severing the inner side of diaphragm adjacent to the pericardium to the hiatus is introduced. This technique was successfully used in 16 cases and the present surgical approach facilitates frontal visualization of the lower esophagus without disruption of the circulatory system. Furthermore, a sufficiently large operative field is obtained and radical dissection of cardia and upper gastric region or combined resection of infiltrated adjacent organs is facilitated. Postoperative recovery of pulmonary function in terms of PaO2 and PaCO2 was similar to that of patients who had received an upper median incision. We found no postoperative complications peculiar to the operative technique introduced here in any of the 16 patients.

Adult↗
PubMed1973

The fine structure and immunological labeling of the achromatic mitotic apparatus after disruption of cell membranes.

After treatment of HeLa and L cells with vinblastine sulfate the material of microtubules (tubulin) was reorganized into (a) large paracrystals (PC) of tightly packed tubules; (b) smaller aggregates of tubules with greater diameter whose walls are constituted from well defined, helically arranged morphological subunits; and (c) microtubules associated with helices of polyribosomes of uniform size. All of these structures survived disruption of cellular membranes by means of a nonionic detergent. Following a thorough stripping of membranes there remained a subcellular fraction sedimenting at 1,500 g for 15 min, in which were contained nuclei, centrioles, and the above mentioned microtubular elements, maintained as a complex of organelles by an interconnecting network of 80 A microfibrils. As a result of membrane disruption it was possible to localize precisely in the electron microscope the binding of ferritin antibody conjugates. Specific labeling at the surface of PC and microtubule aggregates could be demonstrated. This result was substantiated by means of the immunoperoxidase method of labeling the PC. A concentrated deposit of ferritin was also found in the vicinity of centrioles and related structures, the annuli of the nuclear pore complex and the annulate lamellae. However, the specificity of the label on these organelles remains questionable because ferritin, albeit in lower concentration, was also present on them in control preparations reacted with preimmune sera.

Animals↗
PubMed1970

Rapid purification and the immunological specificity of mammalian microtubular paracrystals possessing an ATPase activity.

A new procedure for the rapid purification of vinblastine-induced microtubular paracrystals is described. The paracrystals constitute about 2 per cent of the total protein in L cells. They contain a labile ATPase with a Michaelis constant of 1.0 x 10(-4). In the immunofluorescence test, sera prepared against paracrystals reacted positively with intracellular paracrystals and the mitotic apparatus. Antisera against paracrystals from a malignant murine cell also labeled the mitotic apparatus of HeLa and chicken embryonic cells, revealing the presence of a common or related antigen in the mitotic apparatus of these higher vertebrates.

Adenosine Triphosphatases↗