細胞機能解析学分野

Hiroki Doi

  (土井 洋輝)

Profile Information

Affiliation
Fujita Health University
Degree
博士(医療科学)(2023年3月藤田医科大学)

ORCID ID
 https://orcid.org/0000-0002-3595-6235
J-GLOBAL ID
202201017243025185
researchmap Member ID
R000041120

Papers

 22
  • Hiroki Doi, Hidehiko Akiyama, Taei Matsui, Kazuya Shiogama, Masaya Hirayama, Rie Nakagawa, Sumie Fujii, Hideaki Matsuura, Yasuo Miura
    International Journal of Hematology, Aug 2, 2025  Peer-reviewedLead authorCorresponding author
    This study investigated the anti-tumor effects of andrographolide, a diterpene lactone derived from Andrographis paniculata, on T-cell acute lymphoblastic leukemia (T-ALL) cells. Andrographolide induced dose-dependent cytotoxicity and morphological changes in the T-ALL cell line Jurkat cells, including cell shrinkage and chromatin condensation. Mechanistically, andrographolide triggers apoptosis through reactive oxygen species (ROS) generation, mitochondrial membrane depolarization, and cytochrome c release. These effects were reversed by the ROS inhibitor N-acetyl-L-cysteine (NAC), indicating that andrographolide induces apoptosis through a ROS-dependent apoptotic pathway. In contrast, NAC treatment did not reverse cytarabine- and vincristine-induced apoptosis or the ROS-dependent apoptotic pathway in Jurkat cells. Intriguingly, andrographolide also induced ferroptosis, as evidenced by increased expression of the ferroptosis marker fatty acid-CoA ligase 4 and ultrastructural changes such as reduced mitochondrial area and disappearance of cristae. These effects were likewise reversed by NAC, further implicating ROS in the ferroptotic process. In MOLT-4 cells, where andrographolide suppressed viability, increased Annexin V positivity and ROS levels, and upregulated FACL4 expression in a NAC-sensitive manner. Unlike cytarabine and vincristine, andrographolide did not significantly alter cell cycle distribution. In conclusion, andrographolide induces both apoptosis and ferroptosis in T-ALL cells via ROS-dependent mechanisms that are distinct from those of conventional chemotherapeutic agents. These dual actions position andrographolide as a candidate for standalone or combination therapy in T-ALL.
  • Yuko Abe, Hideaki Matsuura, Ayuna Yamada, Rie Nakagawa, Hayato Kojima, Yuya Ishihara, Hiroki Doi, Sumie Fujii, Yasuo Miura
    Transfusion, 65(2) 354-362, Jan 9, 2025  Peer-reviewed
    Abstract Background Ethylenediamine tetraacetate/glycine acid (EGA) and chloroquine diphosphate (CDP) are used in transfusion testing to dissociate IgG antibodies from red blood cells (RBCs). However, the ability of these reagents to dissociate IgM antibodies sensitized to RBCs has not been comprehensively elucidated. We investigated whether EGA and CDP could dissociate cold‐reactive antibodies from RBCs and their effect on RBCs after dissociation treatment. Study Design and Methods Cold‐reactive antibody‐sensitized RBC samples were prepared by mixing group A RBCs and group B plasma and treated with EGA, CDP, and dithiothreitol (DTT). Before and after the dissociation treatment, changes in the agglutination of these RBCs were assessed using the test tube method. Flow cytometric analysis was used to confirm the nature of antibodies bound to RBCs. Additionally, RBC morphology was evaluated using scanning electron microscopy. This study utilized off‐label use of EGA and CDP. Results Flow cytometric analysis showed that antibodies sensitized to RBCs were mainly IgM antibodies. After antibody dissociation, agglutination disappeared in the EGA‐treated samples to the same degree as in the DTT‐treated samples. However, IgM antibodies remained in the CDP‐treated samples. Regarding RBC morphology, RBC surface appeared coarser in both EGA‐ and CDP‐treated samples, and RBC area was significantly smaller in the CDP‐treated samples than in the EGA‐treated samples. Discussion EGA could dissociate cold‐reactive antibodies, whereas CDP had a higher residual antibody content. This difference in dissociation ability appears to correlate with the antibody pH of the dissociation reagent. EGA treatment may be useful in cases of sensitization by high‐titer cold‐reactive antibodies.
  • Hiroki Doi, Hidehiko Akiyama, Kazuya Shiogama, Sumie Fujii, Hideaki Matsuura, Yasuo Miura
    Blood, 144(Suppl.) 7471, Dec, 2024  
  • Rie Nakagawa, Hideaki Matsuura, Hayato Kojima, Yuko Abe, Ayuna Yamada, Hiroki Doi, Yasuo Miura
    Laboratory medicine, 56(2) 171-177, Sep 22, 2024  Peer-reviewed
    BACKGROUND: Donor-specific antibodies (DSAs) targeting human leukocyte antigens (HLAs) substantially reduce the longevity of transplanted organs. Desensitization of DSA-positive renal transplant recipients is achieved through intravenous administration of immunoglobulin (IVIg). However, the presence and detectability of anti-HLA antibodies in IVIg preparations following administration are not fully understood. We aimed to assess whether immunoglobulin preparations contain anti-HLA antibodies that can be detected as passive antibodies when administered into the body. METHODS: We evaluated 3 immunoglobulin preparations from different pharmaceutical companies, using anti-HLA class I and II antibody specificity tests and immunocomplex capture fluorescence analysis (ICFA). RESULTS: Direct testing for anti-HLA antibodies resulted in high background errors, particularly for Venoglobulin. Diluting Venoglobulin to physiological concentrations revealed the presence of anti-HLA class I antibodies; however, no common alleles were found between the specificity identification test and ICFA.For Glovenin and Venilon, anti-HLA class I and II antibodies were detected; however, variability was observed across different test reagent lots. Moreover, dilution of the globulin formulation revealed a prozone phenomenon. CONCLUSION: The administration of IVIg complicates the accurate detection of anti-HLA antibodies, underscoring the need for careful interpretation of test results post-IVIg administration.
  • Medical Technology, 52(9) 907-913, Sep 1, 2024  

Misc.

 15

Presentations

 33

Works

 1

Research Projects

 4

Other

 2
  • スーパーオキシドの発生などについてミトコンドリア呼吸鎖複合能を標的とした解析系の技術*本研究ニーズに関する産学共同研究の問い合わせは藤田医科大学産学連携推進センター(fuji-san@fujita-hu.ac.jp)まで
  • 特になし