Establishment of novel transgene for in vivo cell tracking by fluorescent imaging

• Project/Area Number: 17K08969
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Applied pharmacology
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: Tahara Tsuyoshi 国立研究開発法人理化学研究所, 生命機能科学研究センター, 客員研究員 (20419708)
• Project Period (FY): 2017-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2018: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000); Fiscal Year 2017: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 蛍光イメージング / トランスジーン / 蛍光プローブ / 細胞トラッキング

Outline of Final Research Achievements

In this research project, we succeeded in constructing a tobacco mosaic virus-derived protease TEVp expression vector and a TEVp-dependent off-on peptide fluorescent probe. After subcutaneously implanting TEVp-expressing human brain tumor cells (TEVp-U87) into immunodeficient mice, fluorescence imaging was performed by 2D-in vivo imaging. As a result, we succeeded in obtaining a specific fluorescence signal at the site of TEVp-U87 implantation. Histochemical examination also confirmed that this signal was derived from TEVp-expressing cells.
Although 3D imaging was not implemented, we were close to developing a new transgene for cell tracking that would improve the S/N ratio.

Academic Significance and Societal Importance of the Research Achievements

本研究で用いた蛍光モダリティは、一般的に生体深部観察は不得意であるが、蛍光とCTを1台で撮像することができる装置を用いることにより　近赤外波長のような長波長であればマウスの深部のシグナルを得ることが可能である。さらにCTイメージにより、生体内のどの位置からシグナルが得られたのか、より詳細に知ることが可能である。また蛍光の長所である空間分解能が高いことから、in vivoイメージングのみならず、どの細胞が取り込んだのか、移植細胞がどれなのかまで、一つのプローブで検討することが可能となる。

Research Products

• [Journal Article] Characteristic Evaluation of a ¹¹C-Labeled Leucine Analog, <scp>l</scp>-α-[5-¹¹C]methylleucine, as a Tracer for Brain Tumor Imaging by Positron Emission Tomography (2023)
  • Author(s): Tahara Tsuyoshi、Takatani Shuhei、Tsuji Mieko、Shibata Nina、Hosaka Nami、Inoue Michiko、Ohno Masahiro、Ozaki Daiki、Mawatari Aya、Watanabe Yasuyoshi、Doi Hisashi、Onoe Hirotaka
  • Journal Title: Molecular Pharmaceutics Volume: 20 Issue: 3 Pages: 1842-1849
  • DOI: 10.1021/acs.molpharmaceut.2c01069
  • Peer Reviewed