Ichikawa, Daiju



Faculty of Pharmacy, Department of Pharmacy 病態生理学講座 (Shiba-Kyoritsu)


Research Associate/Assistant Professor/Instructor


Papers 【 Display / hide

  • Endogenous neurotoxin-like protein Ly6H inhibits alpha7 nicotinic acetylcholine receptor currents at the plasma membrane

    Moriwaki Y., Kubo N., Watanabe M., Asano S., Shinoda T., Sugino T., Ichikawa D., Tsuji S., Kato F., Misawa H.

    Scientific Reports (Scientific Reports)  10 ( 1 )  2020.12

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    © 2020, The Author(s). α7 nicotinic acetylcholine receptors (nAChRs) are widely expressed in the central nervous system and regarded as potential therapeutic targets for neurodegenerative conditions, such as Alzheimer’s disease and schizophrenia. Yet, despite the assumed pathophysiological importance of the α7 nAChR, molecular physiological characterization remains poorly advanced because α7 nAChR cannot be properly folded and sorted to the plasma membranes in most mammalian cell lines, thus preventing the analyses in heterologous expression system. Recently, ER-resident membrane protein NACHO was discovered as a strong chaperone for the functional expression of α7 nAChR in non-permissive cells. Ly6H, a brain-enriched GPI-anchored neurotoxin-like protein, was reported as a novel modulator regulating intracellular trafficking of α7 nAChR. In this study, we established cell lines that stably and robustly express surface α7 nAChR by introducing α7 nAChR, Ric-3, and NACHO cDNA into HEK293 cells (Triple α7 nAChR/RIC-3/NACHO cells; TARO cells), and re-evaluated the function of Ly6H. We report here that Ly6H binds with α7 nAChRs on the cell membrane and modulates the channel activity without affecting intracellular trafficking of α7 nAChR.

  • Antibody drug separation using thermoresponsive anionic polymer brush modified beads with optimised electrostatic and hydrophobic interactions

    Nagase K., Ishii S., Ikeda K., Yamada S., Ichikawa D., Akimoto A.M., Hattori Y., Kanazawa H.

    Scientific Reports (Scientific Reports)  10 ( 1 )  2020.12

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    © 2020, The Author(s). Antibody drugs play an important role in biopharmaceuticals, because of the specificity for target biomolecules and reduction of side effects. Thus, separation and analysis techniques for these antibody drugs have increased in importance. In the present study, we develop functional chromatography matrices for antibody drug separation and analysis. Three types of polymers, poly(N-isopropylacrylamide (NIPAAm)-co-2-acrylamido-2-methylpropanesulfonic acid (AMPS)-co-N-phenyl acrylamide (PhAAm)), P(NIPAAm-co-AMPS-co-n-butyl methacrylate (BMA)), and P(NIPAAm-co-AMPS-co-tert-butylacrylamide (tBAAm)), were modified on silica beads through atom transfer radical polymerisation. Rituximab elution profiles were observed using the prepared beads-packed column. Rituximab adsorption at high temperature and elution at low temperature from the column were observed, as a result of the temperature-modulated electrostatic and hydrophobic interactions. Using the column, rituximab purification from contaminants was performed simply by changing the temperature. Additionally, three types of antibody drugs were separated using the column through temperature-modulated hydrophobic and electrostatic interactions. These results demonstrate that the temperature-responsive column can be applied for the separation and analysis of biopharmaceuticals through a simple control of the column temperature.

  • Characteristics of a novel target antigen against myeloma cells for immunotherapy

    Matsushita M., Saito S., Yokoe S., Ichikawa D., Hattori Y.

    Vaccines (Vaccines)  8 ( 4 ) 1 - 13 2020.12

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    © 2020 by the authors. Licensee MDPI, Basel, Switzerland. Despite the availability of therapeutic treatments, multiple myeloma is an incurable haematological disorder. In this study, we aimed to clarify the role of CXorf48 as a therapeutic target in multiple myeloma. Based on a previously identified HLA-A*24:02-restiricted epitope from this novel cancer/testis antigen, we characterized the activities of cytotoxic T lymphocytes (CTLs) specific to this antigen against myeloma cells and evaluated the effects of demethylating agents in increasing antigen expression and enhancing the cytotoxic activity of CTLs. CXorf48 expression was examined by reverse transcription polymerase chain reaction (RT-PCR) using nine myeloma cell lines. Cell lines with low CXorf48 expression were treated by demethylating agents (DMAs), 5-azacytidine (5-aza), and 5-aza-2'-deoxycytidine (DAC) to evaluate gene expression using quantitative RT-PCR. Furthermore, CXorf48-specific CTLs were induced from peripheral blood mononuclear cells of HLA-A*24:02-positive healthy donors to evaluate antigen recognition using ELISpot and51 Cr cytotoxicity assays. CXorf48 was widely expressed in myeloma cells, and gene expression was significantly increased by DMAs. Furthermore, CXorf48-specific CTLs recognized DMA-treated myeloma cells. These findings suggest that CXorf48 is a useful target for immunotherapy, such as vaccination, in combination with demethylating agents for the treatment of patients with myeloma.

  • Temperature-modulated cell-separation column using temperature-responsive cationic copolymer hydrogel-modified silica beads

    Nagase K., Inanaga D., Ichikawa D., Mizutani Akimoto A., Hattori Y., Kanazawa H.

    Colloids and Surfaces B: Biointerfaces (Colloids and Surfaces B: Biointerfaces)  178   253 - 262 2019.06

    ISSN  09277765

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    © 2019 Elsevier B.V. There is strong demand for cell separation methods that do not decrease cell activity or modify cell surfaces. Here, new temperature-modulated cell-separation columns not requiring cell-surface premodification are described. The columns were packed with temperature-responsive cationic polymer hydrogel-modified silica beads. Poly(N-isopropylacrylamide-co-n-butyl methacrylate-co-N,N-dimethylaminopropyl acrylamide) hydrogels with various cationic moieties were attached to silica-bead surfaces by radical polymerization using N,Nʹ-methylenebisacrylamide as a crosslinking agent. The beads were packed into solid-phase extraction columns, and temperature-dependent cell elution from the columns was found using HL-60 and Jurkat cells. The retention HL-60 and Jurkat cells in columns containing cationic beads at 37 °C was 95.3% to 99.6% and 95.0% to 98.8%, respectively. By contrast, beads without cationic properties exhibited low cell retention (20.6% for HL-60 and 32.5% for Jurkat cells). The cells were mainly retained through both electrostatic and hydrophobic interactions. The retained HL-60 (4.9%) and Jurkat cells (40%) were eluted at 4 °C from the column with a low composition of cationic monomer (DMAPAAm, 1 mol% in copolymer), because the temperature-responsive hydrogels on the beads became hydrophilic, decreasing the hydrophobic interactions between the cells and the beads. A higher number of Jurkat cells than HL-60 cells were eluted because of differences in their electrostatic properties (Jurkat cells: −2.53 mV; HL-60 cells: −20.7 mV). The results indicated that cell retention by the hydrogel-coated beads packed in a solid phase extraction column could be modulated simply by changing the temperature.

  • A phenylphthalimide derivative, TC11, induces apoptosis by degrading MCL1 in multiple myeloma cells

    Ichikawa D., Nakamura M., Murota W., Osawa S., Matsushita M., Yanagawa H., Hattori Y.

    Biochemical and Biophysical Research Communications (Biochemical and Biophysical Research Communications)   2019

    ISSN  0006291X

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    © 2019 To date, the prognosis of multiple myeloma (MM) in patients harboring cytogenetic abnormalities (CA) involving t (4; 14) and deletion of chromosome 17 remains poor despite recent advances in drug development that include the use of immunomodulatory drugs (IMiDs) such as lenalidomide for MM. To address this issue, we have developed a novel phenylphthalimide derivative, TC11, that is structurally related to IMiDs. It remains unclear how TC11 induces apoptosis of MM cells with high-risk CA. Here, we show that TC11 does not induce degradation of CRBN's substrates, IKZF1/3 and CK1α, and induces apoptosis of CRBN-silenced MM; this effect was independent of the cereblon (CRBN) pathway, which is involved in the mechanism of action of IMiDs used for the treatment of MM. We also revealed that TC11, in contrast to existing IMiDs, induced degradation of MCL1 and activation of caspase-9. Furthermore, inhibition of CDK1 by CGP74514A prevented TC11-induced MCL1 degradation, caspase-9 activation, and the subsequent apoptotic cell death. We showed that ectopic MCL1 expression rescued apoptosis of MM. These observations suggest that TC11 induces apoptotic death caused by degradation of MCL1 during prolonged mitotic arrest. Therefore, our findings suggest that TC11 is a potential drug candidate for high-risk MM.

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Papers, etc., Registered in KOARA 【 Display / hide

Reviews, Commentaries, etc. 【 Display / hide

  • E3 ubiquitin ligase in T cell anergy

    ICHIKAWA Daiju

    臨床免疫・アレルギー科 (科学評論社)  62 ( 4 ) 411 - 417 2014.10

    Introduction and explanation (scientific journal),  ISSN  1881-1930

Presentations 【 Display / hide

  • A novel candidate for immunological target in treatment of multiple myeloma.

    Maiko Matsushita, Saku Saito, Kanae Mori, Shinya Yokoe, Daiju Ichikawa, Yutaka Hattori

    An AACR Special Conference on Tumor Immunology and Immunotherapy (Boston Marriott Copley Place,Boston, U.S.A. ) , 2019.11

  • Dedifferentiation by reprogramming genes augments drug resistance and clonal growth in myeloma cells

    Hiroki Tsuji, Takumi Futo, Koichi Samata, Tomofumi Yamamoto, Daiju Ichikawa, Maiko Matsushita, Yutaka Hattori

    The 81th Annual Meeting of the Japanese Society of Hematology, 2019.10, Poster (general)

  • Diverse molecular mechanisms of lenalidomide resistance in multiple myeloma cells

    Takumi Futo, Ryo Uozaki, Takashi Yamaguchi, Tomofumi Yamamoto, Hiroki Tsuji, Koichi Samata, Daiju Ichikawa,Maiko Matsushita, Yutaka Hattori

    The 81th Annual Meeting of the Japanese Society of Hematology, 2019.10, Oral Presentation(general)

  • komaroviquinoneという天然物由来の新規化合物がin vivoにおいて抗MM活性を示す


    第78回日本癌学会学術総会, 2019.09, 国立京都国際会館 京都

  • 天然物由来成分komaroviquinone及びその誘導体群はin vivoにおいて抗骨髄腫活性を示す


    日本薬学会生物系薬学部会第20回Pharmaco-Hematologyシンポジウム (日本薬学会長井記念館 東京) , 2019.06

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Research Projects of Competitive Funds, etc. 【 Display / hide

  • Overcoming resistance to new drug in hematological malignancy tageting LncRNA.


    MEXT,JSPS, Grant-in-Aid for Scientific Research, 市川 大樹, Grant-in-Aid for Scientific Research (C), Principal Investigator

  • Identification of novel therapeutic target molecules and the molecular mechanism for refractory multiple myeloma


    MEXT,JSPS, Grant-in-Aid for Scientific Research, 市川 大樹, Grant-in-Aid for Young Scientists (B), Principal Investigator


Courses Taught 【 Display / hide











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