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K Ishitani

Publications and source records attributed to K Ishitani.

At least 37 records · Page 2Linked to original sources
PubMed1989

Influence of transglutaminase on the functions of mouse peritoneal macrophages.

Influence of transglutaminase on the production of interleukin-1 (IL-1) and on the release of active oxygen from mouse peritoneal macrophages was examined using cystamine and methylamine, an enzyme inhibitor and a substrate inhibitor, respectively. Casein-elicited or lipopolysaccharide (LPS)-elicited macrophages have higher levels of transglutaminase activity in comparison with resident macrophages, and there exists a definite correlation between endocytosis of erythrocytes and transglutaminase activity in either group of macrophages. The release of IL-1 by resident macrophages stimulated with LPS in vitro was significantly inhibited by the treatment with both transglutaminase inhibitors. However, these inhibitors were not able to inhibit the release of IL-1 from casein-elicited macrophages stimulated with LPS in vitro. The production of active oxygen from LPS-elicited macrophages was inhibited in a dose-dependent manner by the treatment of macrophages with cystamine, but was not by the treatment with methylamine. However, the treatment of LPS-elicited macrophages with cystamine did not inhibit the uptake of glucose into macrophages. These results suggest that transglutaminase activity in mouse peritoneal macrophages is an important factor for macrophage functions.

Animals↗
PubMed1988

Influence of arachidonate metabolism on enhancement of intracellular transglutaminase activity in mouse peritoneal macrophages.

We examined whether arachidonate metabolism exerted any influence on the enhancement of intracellular transglutaminase activity in mouse peritoneal macrophages. Enhancement of the intracellular transglutaminase activity was observed on stimulation of macrophages with normal sheep red blood cells (SRBC) or immunoglobulin G (IgG)-coated SRBC, and was inhibited by inhibitors of phospholipase A2 and cyclooxygenase. Moreover, prostaglandin E2 (PGE2), a main product of the cyclooxygenase pathway, leukotriene B4 (LTB4), a product of 5-lipoxygenase, and arachidonic acid also could directly induce high levels of intracellular transglutaminase activity without stimulation of macrophages by SRBC or IgG-coated SRBC, but leukotriene C4, prostaglandin D2, and prostacyclin were unable to induce high activity of the enzyme. Enhancement of transglutaminase activity induced by LTB4 was inhibited by cyclooxygenase inhibitor, but the enzyme activity induce by PGE2 was not inhibited. Furthermore, the quantity of PGE2 released into the culture medium of macrophages stimulated with SRBC or IgG-coated SRBC correlated well with the activity of intracellular transglutaminase in macrophages. Moreover, enhancement of transglutaminase activity by treatment of macrophages with SRBC or IgG-coated SRBC was partially suppressed by sodium benzoate, which is a scavenger of hydroxy radical. These findings suggest that arachidonate metabolism, in particular the cyclooxygenase pathway, plays an important role in the enhancement of intracellular transglutaminase activity.

Animals↗
PubMed1988

Production of leukotrienes from mouse peritoneal macrophages by treatment with a neutral subfraction of bakers' yeast mannan.

We concluded that a neutral subfraction of mannan from bakers' yeast (Saccharomyces cerevisiae wild type strain), abbreviated as WNM, was able to induce the release of leukotrienes from mouse peritoneal macrophages (M phi). The culture supernatant fluid of M phi from normal mice cultured with WNM caused a marked contraction of guinea pig ileum. This activity was inhibited by pretreatment of M phi with inhibitor of phospholipase A2 or lipoxygenase before M phi were treated with WNM, and by treatment of the incubation bath with a slow reacting substance antagonist, FPL55712. On the other hand, pretreatment of M phi with a cyclooxygenase inhibitor potentiated contractile response of ileum by culture supernatant fluid of M phi. A high performance liquid chromatographic analysis of a culture supernatant fluid of M phi treated with WNM demonstrated the presence of leukotrienes C4 and D4, and their related compounds.

Animals↗
PubMed1988

Antitumor activity of polygalactosamine isolated from Paecilomyces sp. I-1 strain.

The inhibitory effect of polygalactosamine (PF102), which was isolated from Paecilomyces sp. I-1 strain, on a syngeneic murine solid tumor and its antitumor mechanism were studied. After an intravenous injection of PF102, 1 microgram/kg, an increase in cell mediated and humoral immunities in mice was observed and the growth inhibition of MM46 solid tumor in vivo was also evident. Macrophages induced by PF102 into the peritoneal cavity inhibited deoxyribonucleic acid synthesis of target cells. Moreover, PF102 caused a significant increase in the incorporation of 3H-thymidine into the thymic cells and the culture supernatant of T lymphocytes, stimulated with PF102, exhibited a marked activation of the cytostatic effect of the peritoneal macrophages. Furthermore, this culture supernatant fluid was found to contain interferon (IFN). Therefore, the antitumor activity of PF102 might be due in part to the activation of the macrophage lineage cells by macrophage activating factor and/or IFN produced from T lymphocytes stimulated by PF102.

Animals↗
PubMed1985

[Analysis of human sera obtained from lung cancer patients by two-dimensional electrophoresis after schizophyllan (SPG) treatment].

Schizophyllan (SPG) was administered to 13 lung cancer patients (i.m. 20mg X 2/week) for 3 weeks without chemo or irradiation therapies, and serum proteins were analyzed by two-dimensional electrophoresis (TDE). Additionally, immunosuppressive acidic protein (IAP) was quantitatively determined by single radial immunodiffusion (SRID). By TDE analysis, human serum proteins were separated into more than 100 spots, and about 14 spots were found to show quantitative changes in cancer patients. Quantitative examination was therefore conducted on changes of 8 components among these spots, including alpha 1-acidic glycoprotein (alpha 1 AG), acidic alpha 2-macroglobulin (acidic alpha 2 M), haptoglobin (Hp) and IAP. The protein which showed the most marked decrease in cancer patients, located between transferrin and IgG on the above TDE patterns, was ascertained to have a molecular weight of about 150,000 using a gel filtration method. This protein was increased in 7 of 13 patients after SPG treatment.

Adenocarcinoma↗
PubMed1985

[Clinical phase II study of 5'-DFUR for cancer of the digestive organs by a cooperative study group].

Phase II study of a new 5-fluorouracil derivative, 5'-deoxy-5-fluorouridine (5'-DFUR), was performed with oral administration. Forty-nine patients with advanced cancer of the digestive organs, lung and breast were entered, and 8 institutions in Hokkaido were involved. 5'-DFUR was administered three or four times a day at a daily dosage of 600 to 1200 mg. Partial response was observed in three gastric cancer cases and two breast cancer cases out of 39 evaluable cases, and minor response was observed in one colorectal cancer case. Overall response rate was 12.8%, 15.8% in gastric cancer and 66.7% in breast cancer. Side effects were observed in 15 cases out of 45 (33.3%), which mainly consisted of gastro-intestinal disturbances such as diarrhea.

Adenocarcinoma↗
PubMed1983

[Multiple plasma exchanges in patients with advanced malignant disease].

Multiple plasma exchange represents an empirical attempt to clear "immunosuppressive factors" from the plasma of cancer patients. Plasma exchanges have been performed in 32 patients with advanced malignant disease. Up to 4000 ml of plasma have been replaced by one single plasma exchange. Serum proteins including acute phase reactants were monitored before and after plasma exchange. A transient change of these proteins was observed on the first day, but later on, pretreatment values were always regained. Skin reactions to recall and new antigens were enhanced in many patients after plasma exchanges. Peripheral blood lymphocyte blastogenic response to mitogen was slightly increased in patients after plasma exchanges. Plasma exchange was found to decrease significantly the inhibitory effect of patients' sera on normal donor lymphocyte reactivity. Therefore, multiple plasma exchanges could have a practical role to play in immunotherapy.

Aged↗
PubMed1977

Immunosuppressive factors in serum of patients with gastric carcinoma.

Sera from patients with gastric carcinoma markedly suppressed the normal lymphocyte response to phytohemagglutinin (PHA) when compared with normal sera. The effect of this inhibition was well correlated with the degree of advance of the disease. Fractionation of normal and cancerous sera was carried out by DEAE-cellulose column chromatography using a continuous concave gradient. The elution patterns of the two kinds of sera were quite similar and separated into nine fractions. Protein analysis by immunoelectrophoresis and immunodiffusion showed no difference in subfractions between normal and cancerous sera. However, inhibitory activities of cancerous sera on PHA response of normal lymphocytes were found in alpha-globulin, beta-globulin, and alpha2-macroglobulin fractions. On the other hand, in the fractions from normal serum, alpha- and beta-globulin fractions showed a similar degree of inhibition to PHA response of normal lymphocytes, but alpha2-macroglobulin fraction had no inhibitory activity. Such inhibitory fractions showed an immunosuppressive activity not only to PHA response of normal lymphocytes in vitro, but also due to the induction of splenic plaque-forming cells in vivo. The electrofocusing patterns of alpha2-macroglobulin fractions obtained from normal and cancerous sera showed a remarkable difference in protein composition. These results indicated that the function of lymphocytes may be regulated by a variety of humoral factors and, especially in patients with gastric carcinoma, the cell-mediated immunity may be modified by some factors not present in normal serum.

Alpha-Globulins↗
PubMed1975

Differences in subunit composition and iron content of isoferritins.

Horse spleen ferritin was fractionated into its constituent isoferritins by isoelectric focusing. Separated isoferritins were stable and showed no tendency to redistribute when re-examined by analytical gel focusing. All of the isoferritins were immunologically indistinguishable when tested with antibodies raised against unfractionated horse spleen ferritin. The separated isoferritins also had similar conformations as determined by circular dichroism. Iron distribution studies, however, revealed a wide disparity among the isoferritins. The most acidic components had the lowest iron content but the iron content did not vary systematically throughout the isoferritin spectrum. Natural apoferritin, isolated from the ferritin by density gradient centrifugation, focused exclusively as the acidic moieties, whereas apoferritin prepared by reduction of native ferritin exhibited a banding pattern similar to that of unfractionated ferritin. The subunit structure of the isoferritins was examined by gel electrophoresis in sodium dodecyl sulfate or acidic urea systems. Multiple subunit types were demonstrated by both methods. The relative proportion of these subunit types varied progressively through the isoferritin spectrum. This difference in subunit population appears to be the basis for much of the structural heterogeneity in the apoferritin shells.

Animals↗
PubMed1975

Characterization of the different polypeptide components and analysis of subunit assembly in ferritin.

Ferritin was dissociated into subunits by various denaturants and the subunits were examined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Human, horse, rat, and rabbit ferritins all exhibited characteristic patterns of heterogeneity; components with molecular weights of about 19,000, 11,000, and 8,000 were invariably found in these preparations. This result contradicts earlier reports that ferritin consists of 24 identical subunits. These polypeptides were isolated, purified in the presence of low concentrations of detergent, and characterized. Evidence based on amino acid compositions, NH2-terminal analysis and investigation of detergent-induced breakdown products, indicated that the 19,000 molecular weight component is a composite of the 8,000 and 11,000 molecular weight chains. Circular dichroism studies showed that the 19,000 molecular weight polypeptide retained appreciable amounts of ordered secondary structure whereas the two lower molecular weight peptides were unfolded to a much greater extent. If the 8,000 and 11,000 molecular weight polypeptides were recombined in equimolar amounts and the denaturant was completely removed, a substance with electrophoretic mobility and morphological appearance of native apoferritin was obtained.

Amino Acids↗