産学連携推進センター

瀬戸 孝一

seto koichi

基本情報

所属
藤田医科大学 研究推進本部 産官学連携推進センター 未来共創イノベーション室
学位
薬学博士

J-GLOBAL ID
201901010015875519
researchmap会員ID
7000029395

論文

 30
  • Hidetsugu Fujigaki, Masao Takemura, Michiko Osawa, Aki Sakurai, Kentaro Nakamoto, Koichi Seto, Takashi Fujita, Tadayoshi Hata, Hidehiko Akiyama, Yohei Doi, Kuniaki Saito
    Heliyon 6(9) e04929-e04929 2020年9月  査読有り
    Background: Several immunochromatographic serological test kits have been developed to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibodies, but their relative performance and potential clinical utility is unclear. Methods: Three commercially available serological test kits were evaluated using 99 serum samples collected from 29 patients diagnosed with coronavirus disease 2019 (COVID-19) and 100 serum samples collected from 100 healthy volunteers in 2017 as negative controls. Results: The specificity of the IgM and IgG antibodies showed comparable results among the three immunochromatographic serological test kits. The specificity for IgM antibody was 98.0%, 98.0%, and 97.0%, and the specificity for IgG antibody was identical among the three kits (99.0%). The IgM antibody-positive rates of the three test kits for samples taken at the early stage of the disease (0-4 days after onset) were consistent with all three kits (18.2%); however, the IgM antibody-positive rates thereafter showed considerable differences among the kits, making it difficult to interpret the kinetics of IgM response against SARS-CoV-2. The IgG antibody-positive rates for samples taken after 13 days of onset were 100.0%, 97.6%, and 97.6%, respectively. Conclusion: There were large differences among the results of the three test kits. Only few cases showed positive results for IgM, suggesting that at least 2 of these kits used in this study were unsuitable for diagnosis of COVID-19. The IgG antibody was positive in almost all samples after 13 days of onset, suggesting that it may be useful for determining infections in the recent past.
  • Katsunuma K, Yoshinaga K, Ohira Y, Eta R, Sato T, Horii T, Tanaka T, Takei M, Seto K
    Molecular immunology 64(1) 218-227 2015年3月  査読有り
  • Takayuki Horii, Koji Yoshinaga, Nobuyoshi Kobayashi, Koichi Seto, Yuki Orikawa, Masahiro Okamoto, Runa Eta, Yuta Ohira, Kokichi Katsunuma, Yuko Hori, Takao Tanaka, Mineo Takei
    BIOLOGICAL & PHARMACEUTICAL BULLETIN 37(4) 642-647 2014年4月  査読有り
    Lymphatic metastasis is common in advanced-stage carcinoma and is associated with a poor prognosis. However, few effective treatments to inhibit it are available. Z-100 is an immunomodulatory extract of Mycobacterium tuberculosis strain Aoyama B that contains polysaccharides such as arabinomannan and mannan. Here, we investigated the inhibitory effect of Z-100 on spontaneous lymphatic metastasis. C57BL/6N mice injected subcutaneously with B16-BL6 melanoma cells in the right hind footpad were administered Z-100 subcutaneously in the right inguinal region on a daily basis. On day twenty-one after the injection, the right inguinal lymph nodes were excised, and the extent of metastasis, the number of immune cells, and the amount of granzyme B protein in the lymph nodes were examined. We also investigated the combined effect of Z-100 and irradiation in this model. Results showed that Z-100 reduced number of animals with metastasis, with respective metastasis rates of 85.7%, 42.9%, 7.1% and 0.0% in saline, 0.1 mg/kg Z-100, 1 mg/kg Z-100 and 10mg/kg Z-100 group. Further, mice that had been given Z-100 were found to have more immune cells and granzyme B protein in the lymph nodes than control mice. The combination of low dose Z-100 and irradiation also inhibited spontaneous lymph node metastases. These findings suggest that Z-100 may be beneficial in preventing lymphatic. metastasis by enhancing the immune response.
  • Hiroki Kato, Koichi Seto, Nobuyoshi Kobayashi, Koji Yoshinaga, Tim Meyer, Mineo Takei
    LIFE SCIENCES 89(17-18) 603-608 2011年10月  査読有り
    Aims: As activation and overexpression of the cholecystokinin-2 (CCK-2)/gastrin receptor can lead to carcinogenesis, it has been explored as a therapeutic target in pancreatic cancer. We demonstrated that Z-360, a CCK-2/gastrin receptor antagonist, combined with gemcitabine prolonged survival and reduced gemcitabine-induced vascular endothelial growth factor (VEGF) expression in a pancreatic carcinoma orthotopic xenograft mouse. In this study, we investigated the role of the CCK-2/gastrin signaling pathway on gemcitabine-induced VEGF expression in PANC-1 human pancreatic carcinoma cells. Main methods: In PANC-1 cells treated with Z-360, anti-gastrin IgG or kinase inhibitors, the gene expression levels were analyzed by quantitative real-time RT-PCR, and the protein levels of Akt and phosphorylated Akt (p-Akt) in cellular extracts were measured by ELISA. Key findings: Gemcitabine-induced expression of VEGF and hypoxia-inducible factor-1 alpha (HIF-1 alpha) were suppressed by the treatment with an anti-gastrin antibody. In addition, VEGF and HIF-1 alpha gene expression was inhibited by treatment with an inhibitor of phosphatidylinositol 3-kinase (PI3K), which is involved in the downstream signaling pathway of the CCK-2/gastrin receptor, and was also suppressed by treatment with Z-360. Moreover, although Akt phosphorylation was increased by treatment with gemcitabine, this elevation was partially, but significantly, inhibited by an exposure of Z-360. Significance: Gemcitabine might induce gene expression of VEGF via the PI3K/Akt signaling pathway in the downstream of the CCK-2/gastrin receptor. The suppression of the CCK-2/gastrin signaling pathway by treatment with Z-360 could be a useful approach for potentiating prolonged survival of pancreatic cancer patients receiving gemcitabine therapy. (C) 2011 Elsevier Inc. All rights reserved.
  • Nobuyoshi Kobayashi, Koichi Seto, Takahiro Sasaki, Kokichi Katsunuma, Yuki Orikawa, Makoto Yoshimura, Yoshihiro Shiomi, Yuta Ohira, Minco Takei, Koichiro Tanaka
    GASTROENTEROLOGY 140(5) S603-S603 2011年5月  査読有り

MISC

 18

担当経験のある科目(授業)

 1

共同研究・競争的資金等の研究課題

 1