Establishing TSPO-PETimaging for the diagnosis of liver diseases

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K16495
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Radiation science
• Research Institution: National Institutes for Quantum and Radiological Science and Technology
• Principal Investigator: XIE Lin 国立研究開発法人量子科学技術研究開発機構, 放射線医学総合研究所 先進核医学基盤研究部, 主任研究員(定常) (30623558)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: TSPO / 先制医療 / 肝疾患 / PET診断

Outline of Final Research Achievements

Recently we developed a novel noninvasive approach for diagnosing steatohepatitis, namely [18F]FEDAC-PET, based on visualizing the translocator protein (18 kDa)(TSPO)-a mitochondrial transmembrane protein. To explore the feasibility of the imaging strategy in clinical practice, we here evaluated and quantified the TSPO expression and [18F]FEDAC binding density in 50 human liver subjects. Our results showed the expression of TSPO protein was much higher in steatohepatitis than in not steatohepatitis, with increasing [18F]FEDAC binding density. We also found for the first time a close correlation in human liver subjects between liver pathological scores and TSPO level, [18F]FEDAC binding density. This study demonstrated [18F]FEDAC-PET can serve as noninvasive diagnostic method to identify patients with steatohepatitis with sufficient accuracy to be considered for clinical use.

Free Research Field

医歯薬学

Academic Significance and Societal Importance of the Research Achievements

これまでに、我々は進行性脂肪肝疾患マウスに対し、発症及び病気進展の先行指標である蛋白質TSPOをバイオマーカーとして特定した上で、TSPOに特異的な分子プローブ[18F]FEDACを開発し、PETでTSPOを可視化することにより、世界で初めて脂肪肝疾患の進行度を判定できる非侵襲的なPET診断法の開発に成功した。今回の研究は、ヒト肝臓を用いたことにより、TSPO及び[18F]FEDAC-PETの有用性を明らかにすることで、肝疾患におけるTSPO-PET診断法が臨床実用化へ加速することはより一層期待される。