Genomic instability of HTLV-1 provirus and application to clinical testing for adult T-cell leukaemia.

• Project/Area Number: 20K07670
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 50020:Tumor diagnostics and therapeutics-related
• Research Institution: National Institute of Infectious Diseases
• Principal Investigator: Kuramitsu Madoka 国立感染症研究所, 次世代生物学的製剤研究センター, 室長 (00566383)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2022: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2021: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2020: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
• Keywords: HTLV-1 / genomic deletion / provirus / digital PCR / Adult T-cell Leukemia / 成人T細胞白血病 / ゲノム不安定性 / 遺伝子欠失 / 定量PCR / デジタルPCR

Outline of Research at the Start

HTLV-1は、成人T細胞白血病（Adult T-cell leukemia, ATL）の原因となるレトロウイルス
である。感染者の95％は生涯無症候であるが、5％でATLが発症する。ATLには高頻度で5'LTRやgag-pol領域等のHTLV-1ゲノムの欠失があることが知られるが、無症候者のHTLV-1ゲノムの欠失は極めて稀である。このことから、HTLV-1ゲノム欠失は約半数のATLのバイオマーカーになると考えられる。本研究においてHTLV-1ゲノム欠失の臨床における実態と欠失のメカニズムを解析し、ATLの早期発見マーカーとして臨床検査におけるHTLV-1ゲノム欠失検出法を開発する。

Outline of Final Research Achievements

Deletion of the HTLV-1 proviral genome is known to occur at a high rate in adult T-cell leukaemia (ATL). In order to apply the detection of deletion of the proviral genome to clinical testing, the development of a quantitative assay was investigated.
Three sets of HTLV-1-specific primer-probes were designed and multiplexed (3-plex) by digital PCR to measure the relative ratio of HTLV-1 gene regions. The results of the examination of clinical specimens showed that deletions with a difference of more than 20% in the pX region could be detected at a viral load of more than 1.0%. Deletions were also detected in an extremely high proportion of some ATLs. This study shows that digital PCR can quantitatively and sensitively detect HTLV-1 provirus deletions.

Academic Significance and Societal Importance of the Research Achievements

成人T細胞白血病（ATL）では、高頻度にHTLV-1ゲノムの欠失があることが知られ、また欠失型のプロウイルスを有するATLでは、完全型と比べて治療成績が異なることが報告されたことから、臨床検査でATL発症者のプロウイルスの欠失を簡便かつ鋭敏に捉えることは、治療戦略の策定にも役立ち重要と考えられる。本研究で開発したデジタルPCR法で、一部のATLでは欠失型プロウイルスが極めて高い割合を占めることを示ことが出来、プロウイルス欠失を定量的かつ高感度に検出できることを示した。臨床検査への応用が可能であることが確認された意義は大きいと考えられる。

Research Products

• [Journal Article] How we secured a COVID-19 convalescent plasma procurement scheme in Japan. (2021)
  • Author(s): Terada M, Kutsuna S, Togano T, et al.
  • Journal Title: Transfusion Volume: 61(7) Issue: 7 Pages: 1998-2007
  • DOI: 10.1111/trf.16541
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] No SARS-CoV-2 RNA detected in the convalescent plasma of COVID-19 patients with different disease severity (2021)
  • Author(s): Hidetoshi Nomoto, Satoshi Kutsuna, Kazu Okuma, Madoka Kuramitsu, Kenta Tezuka, Emi Ikebe, Sho Saito, Noriko Kinoshita, Mari Terada, Mio Endo, Tetsuya Suzuki, Yusuke Miyazato, Takato Nakamoto, Makoto Inada, Isao Hamaguchi, Norio Ohmagari.
  • Journal Title: J Infect Chemother. Volume: 27(4) Issue: 4 Pages: 653-655
  • DOI: 10.1016/j.jiac.2021.01.004
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] First case of molecularly identified and genetically characterized human T-cell leukemia virus type 2 infection in a pregnant woman in non-endemic Japan (2021)
  • Author(s): Kuramitsu Madoka、Okuma Kazu、Horiya Madoka、Sekizuka Tsuyoshi、Kaneko Noriaki、Saito Ema、Sokunaga Jun、Kuroda Makoto、Hamaguchi Isao
  • Journal Title: Journal of Virological Methods Volume: 287 Pages: 114005-114005
  • DOI: 10.1016/j.jviromet.2020.114005
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Establishment of a novel diagnostic test algorithm for human T-cell leukemia virus type 1 infection with line immunoassay replacement of western blotting: a collaborative study for performance evaluation of diagnostic assays in Japan, (2020)
  • Author(s): Okuma K, Kuramitsu M, Niwa T, et al.(40人中17番目)
  • Journal Title: Retrovirology Volume: 17 Issue: 1 Pages: 26-26
  • DOI: 10.1186/s12977-020-00534-0
  • Peer Reviewed / Open Access
• [Journal Article] Activation of PERK-ATF4-CHOP pathway as a novel therapeutic approach for efficient elimination of HTLV-1-infected cells (2020)
  • Author(s): Ikebe E, Matsuoka S, Tezuka K, Kuramitsu M, Okuma K, Nakashima M,, Seiichiro Kobayashi S, Makiyama J, Yamagishi M, Oyadomari S, Uchimaru K, Hamaguchi I
  • Journal Title: Blood adv Volume: 4 Issue: 9 Pages: 1845-1858
  • DOI: 10.1182/bloodadvances.2019001139
  • Peer Reviewed / Open Access
• [Journal Article] Frequent horizontal and mother-to-child transmission may contribute to high prevalence of STLV-1 infection in Japanese macaques (2020)
  • Author(s): Murata Megumi、Yasunaga Jun-ichirou、Washizaki Ayaka、Seki Yohei、Kuramitsu Madoka、Tan Wei Keat、Hu Anna、Okuma Kazu、Hamaguchi Isao、Mizukami Takuo、Matsuoka Masao、Akari Hirofumi
  • Journal Title: Retrovirology Volume: 17 Issue: 1 Pages: 1-10
  • DOI: 10.1186/s12977-020-00525-1
  • Peer Reviewed / Open Access
• [Journal Article] HTLV-1 targets human placental trophoblasts in seropositive pregnant women (2020)
  • Author(s): Tezuka Kenta、Fuchi Naoki、Okuma Kazu、Tsukiyama Takashi、Miura Shoko、Hasegawa Yuri、Nagata Ai、Komatsu Nahoko、Hasegawa Hiroo、Sasaki Daisuke、Sasaki Eita、Mizukami Takuo、Kuramitsu Madoka、Matsuoka Sahoko、Yanagihara Katsunori、Miura Kiyonori、Hamaguchi Isao
  • Journal Title: Journal of Clinical Investigation Volume: 130 Issue: 11 Pages: 6171-6186
  • DOI: 10.1172/jci135525
  • Peer Reviewed / Open Access
• [Journal Article] A high-throughput detection method for the clonality of Human T-cell leukemia virus type-1-infected cells in vivo (2020)
  • Author(s): Saito M, Hasegawa H, Yamauchi S, Nakagawa S, Sasaki D, Nao N, Tanio M, Wada Y, Matsudaira T, Momose H, Kuramitsu M, Yamagishi M, Nakashima M, Nakahata S, Iha H, Ogata M, Imaizumi Y, Uchimaru K, Morishita K, Watanabe T, Miyazaki Y, Yanagihara K.
  • Journal Title: Int J Hematol. Volume: 112 Issue: 3 Pages: 300-306
  • DOI: 10.1007/s12185-020-02935-5
  • Peer Reviewed / Open Access
• [Presentation] Elucidation of the mechanism of transplacental and horizontal HTLV-1 transmission using a novel cell-free infection system (2023)
  • Author(s): Koh Nagata, Kenta Tezuka, Madoka Kuramitsu, Naoki Fuchi, Yuri Hasegawa, Kiyonori Miura, Isao Hamaguchi
  • Organizer: 日本産科婦人科学会
• [Presentation] イムノクロマト法による新規HTLV-1抗体検査法の性能評価―多施設共同研究 (2022)
  • Author(s): 倉光球、石塚賢治、久保田龍二、佐藤知雄、山野嘉久、橋倉悠輝、梅北邦彦、野坂生郷、長谷川寛雄、三浦清徳、宇都宮與、高起良、相良康子、蕎麦田理英子、佐竹正博、浜口功
  • Organizer: 第８回日本HTLV-1学会学術集会