Yuki Akuzawa
Gunma University
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FEBS Letters | 1986
Katsuaki Sugioka; Minoru Nakano; Satonori Kurashige; Yuki Akuzawa; Toshio Goto
When a Cypridina luciferin analog (the title compound) was added to a macrophage suspension in Hanks balanced salt solution (control), the system emitted a weak, but detectable light, which was not altered in the presence of Superoxide dismutase. The same system, however, emitted a much stronger light, just after the addition of a trigger, opsonized zymosan. The luminescence was suppressed to the control level in the presence of superoxide dismutase, while it was only slightly influenced, if at all, by NaN3, a scavenger of singlet oxygen and an inhibitor of myeloperoxidase. Some other results obtained also indicate the participation of O2 − in the luciferin analog‐dependent luminescence in macrophages during phagocytosis.
The American Journal of Chinese Medicine | 1994
Rui Jin; Ling Ling Wan; Toshimi Mitsuishi; Shinobu Sato; Yuki Akuzawa; Kazue Kodama; Satonori Kurashige
Shi-Ka-Ron is a prescription composed of 8 crude extracts of Chinese herbs. It reduces suppression of cytokine production by peritoneal macrophages in mice Immunocompromised by the anti-tumor agent, cyclophosphamide (CY), in vivo. Although it dose not increase IL-1 production in vitro, it enhances TNF production. We found that Ginseng radix, Lithospermi radix, Astragli radix and Glycyrrhizae radix somewhat reduced suppression of cytokine production in CY treated macrophages. Especially, Glycyrrhizae radix shows an active immune response both in vivo and in vitro. Our results suggested that the mechanism underlying immunomodulation of Shi-Ka-Ron is closely related to cytokine production: each herb stimulating macrophages.
Scandinavian Journal of Immunology | 1985
Satonori Kurashige; Yuki Akuzawa; Susumu Mitsuhashi
Coformycin, which is an inhibitor of adenosine deaminase, significantly inhibited in vitro blastogenic responses of human lymphocytes to both phytohaemagglutinin (PHA) and pokeweed mitogen (PWM), whereas blastogenic responses to bacterial lipopolysaccharide (LPS) were rather enhanced by the addition of coformycin. Blastogenic responses of lymphocytes to PHA and PWM were markedly suppressed by the addition of adenosine, which is a substrate of adenosine deaminase. Allopurinol, which is an inhibitor of xanthine oxidase, inhibited blastogenic responses of human lymphocytes to PHA, PWM, and bacterial LPS. Inosine (a substrate of purine nucleoside phosphorylase) and hypoxanthine (a substrate of xanthine oxidase) showed no or only a small effect on blastogenic responses of human lymphocytes. These results suggest that adenosine deaminase activity is associated with the T‐cell response but not with the B‐cell response and that the impaired T‐cell response in adenosine deaminase deficiency is the result of intracellular retention of adenosine in T cells. The results also suggest that purine nucleoside phosphorylase or xanthine oxidase activity is associated with both T‐ and B‐cell responses.
Microbiology and Immunology | 1982
Satonori Kurashige; Yuki Akuzawa; Toshiharu Yoshida; Chisato Teshima; Susumu Mitsuhashi
The distribution of adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) activities in lymphoid organs and lymphocyte subpopulations in mice, and the effect of phytohemagglutinin P (PHA‐P) and concanavalin A (Con A) on the enzyme activities were studied. ADA activity was distributed equally in cells from all organs used and no mouse strain differences were observed. In contrast, PNP activity varied with the mouse strain, being highest in C57BL/6 mice and lowest in BALB/c mice, and with the organ in ICR mice, being high in peripheral blood lymphocytes and spleen lymphocytes, low in mesenteric lymph node cells and absent or very weak in thymus cells. T and B lymphocytes were prepared from spleens of ICR mice. High ADA activity was found in both T and B lymphocytes, whereas PNP activity in the T lymphocytes was about one‐third of that in the B lymphocytes. PNP activity in thymus cells was increased to the normal level of T lymphocytes in the spleens by cultivation without stimulant. The development of PNP activity in thymus cells was partially inhibited by Con A but was not affected by PHA‐P. ADA activity in thymus cells was enhanced by in vitro stimulation with PHA‐P but not with Con A. In contrast, in spleen lymphocytes the development of ADA activity was enhanced by stimulation with PHA‐P and Con A, and that of PNP activity was enhanced by PHA‐P but not by Con A.
Microbiology and Immunology | 1982
Satonori Kurashige; Yuki Akuzawa; Toshiharu Yoshida; Chisato Teshima; Kazue Kodama; Susumu Mitsuhashi
ICR mice were immunized with sheep red blood cells (sRBC). Both adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) activities in spleen lymphocytes increased faster than the serum antibody titer and reached a peak one week after the immunization. ADA activity increased significantly in T lymphocytes but not in B lymphocytes collected from the spleens of the immunized mice. A statistically significant increase in PNP activity was found in both T and B lymphocytes from the spleens of the immunized mice.
Cancer Immunology, Immunotherapy | 1985
Sotonori Kurashige; Yuki Akuzawa; Susumu Mitsuhashi
SummaryThe subcutaneous growth of EL4 cells was significantly accelerated when they were injected together with spleen cells collected from mice which had received EL4 cells SC 14 days previously, and all mice died within 18 days after receiving this mixture; 80% of mice which received a mixture of EL4 and spleen cells collected immediately after EL4 graft survived over 40 days. Spleen cells collected 14 days after EL4 graft suppressed the blastogenic responses of normal spleen lymphocytes to concanavalin A, pokeweed mitogen, and lipopolysaccharide of Escherichia coli in a mixed culture system.Acceleration of tumor growth was retarded when EL4 cells were injected together with spleen cells from EL4-bearing mice treated with both Salmonella typhimurium mini-cells and mitomycin C, and 60% of mice survived over 40 days. Blastogenic responses of normal spleen lymphocytes mixed with spleen cells from EL4-bearing mice treated with both mini-cells and mitomcycin C were restored almost to control levels. The results suggest that combination treatment with mini-cells and mitomycin C synergistically inhibits the induction of suppressor cells in EL4-bearing mice.
Microbiology and Immunology | 1993
Toshimi Mitsuishi; Yuki Akuzawa; Shinobu Sato; Jin Rui; Kazue Kodama; Kinji Inoue; Satonori Kurashige
TtT/M‐87 cell is a macrophage cell line established from thyrotropic pituitary tumor tissues in mouse. In this paper, we report the immunological properties of M‐87 cells as a model of tumor‐associated macrophage. Contrasting with resident peritoneal macrophages, M‐87 cells constitutively secreted small but significant amounts of TNF‐α and IL‐1α, which were detectable in both biological assays (cytotoxic activity for L929 and co‐mitogenic activity for Con A‐induced T cell proliferation, respectively) and ELISA, and produced larger amounts of these cytokines upon stimulation with LPS. They expressed MHC class II molecules on their cell surface without stimulation by IFN‐γ. The accessory or antigen‐presenting cell activity in antibody‐producing response of spleen lymphocytes to sheep red blood cells was shown to be much higher in M‐87 cells than normal peritoneal macrophages. In addition, when normal spleen lymphocytes were cultured with allogeneic tumor cells, such as EL‐4 and S‐180, in the presence of M‐87 cells, lymphocytes reactive to stimulator cells were activated to manifest inhibitory effect on the tumor cell growth and also to manifest specific cytotoxic effect on the allogeneic tumor cells. These results show that M‐87 cells derived from tumor‐associated tissue are activated macrophages and that they are inhibitory to tumor cell growth and augmentative in the induction of T‐cell‐mediated immune responses.
Cancer Investigation | 1998
Shinobu Sato; Satsuki Kimura; Tadashi Nakamura; Yuki Akuzawa; Kazue Kodama; Ken Furukawa; Satonori Kurashige
A significant inhibition of tumor growth was observed when sarcoma 180 (S180)-bearing ICR strain mice were treated by a combination therapy, with a low dose of cyclophosphamide (CY) and an inoculation of allogeneic lymphocytes collected from C57BL/6 mice. The growth-inhibitory effect was significantly increased by an inoculation of a relatively lower dose of allogeneic lymphocytes (1 x 10(5) cells) and CY. The effector cells induced in the mice treated with CY and allogeneic lymphocytes expressed the Lyt 1.2, Lyt 2.2, IL-2R antigens on their membrane surface and did not express the H2KbDb (donor H-2) antigen, and they showed a specific cytostatic activity against S180 cells. These results strongly suggested that a combination therapy with a low dose of CY with an inoculation of allogeneic lymphocytes augmented an induction of specific cytotoxic T lymphocytes in the tumor-bearing recipient mice.
The annual reports of College of Medical Care and Technology | 1989
Satonori Kurashige; Yuki Akuzawa; Kazue Kodama
The annual reports of College of Medical Care and Technology | 1994
Yuki Akuzawa; Sonoko Motai; Saburo Sekiguchi; Kazuo Takezawa; Masae Nakamura; Namiko Uehara; Hatsue Mori; Mitsuaki Sugita; Mariko Niibe; Toshimi Mitsuishi; Satomori Kurashige