Molecular cytological clarification of pathogenesis of male infertility by analyzing genetically modified animals and its clinical application

• Project/Area Number: 19K09665
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 56030:Urology-related
• Research Institution: Chiba University
• Principal Investigator: Ito Chizuru 千葉大学, 大学院医学研究院, 講師 (80347054)
• Co-Investigator(Kenkyū-buntansha): 武藤 透 千葉大学, 大学院医学研究院, 技術専門職員 (30422265)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2021: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2020: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2019: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
• Keywords: 男性不妊症 / 遺伝子改変マウス / 遺伝子欠損雄性不妊モデルマウス / 中心体関連タンパク質 / ODF2 / DDS-頭部離断精子 / ODF4 / ヘアピン鞭毛精子 / 遺伝子改変不妊症モデルマウス / Odf4遺伝子欠損マウス / Odf4-EGFPトランスジェニックマウス / Odf4レスキューマウス / Odf4-EGFP トランス ジェニックマウス / Odf2遺伝子欠損ヘテロマウス / Odf2ハプロ不全 / DDS-頭尾離断精子 / Odf4-EGFP トランスジェニックマウス / 遺伝子改変男性不妊症モデルマウス / エクアトリン / Odf2

Outline of Research at the Start

不妊症の約半分は男性に起因するため、正確な精子機能検査は不妊症の診断と治療に必須ですが、全国共通の評価法はまだ確立されていません。精子が父親の遺伝情報を卵子に運ぶためには、正常形態と運動能を持つだけではなく、先体反応やキャパシテーション、透明帯通過、卵子細胞膜との接着と融合、卵活性化能などの複雑な過程を正常に起こす能力が必要であり、これらを備えたものが良質の精子です。本研究では、遺伝子改変不妊モデル動物を用いて、精子-卵子細胞膜接着-融合に関連するEquatorinと中心体関連分子Odf2および線毛関連分子Odf4を対象に不妊症の原因を解明し、診断と治療に応用することを目的としています。

Outline of Final Research Achievements

Odf2 haploinsufficiency induces sperm neck-midpiece separation, a new type of decapitated and decaudated spermatozoa (DDS). DDS is untreatable in reproductive medicine.The headnecks of ODF2-DDS spermatozoa are, however, alive and capable of producing offspring by intracytoplasmic headneck sperm injection (ICSI). ICSI in humans, using headneck sperm cells, is viable and could be an alternative for infertile patients suffering from Odf2-DDS（Ito et al, Sci.Rep.,2019). Odf4 knockout male mice are infertile. Their spermatozoa progress backward and fail to ascend in the uterus owing to bent (hairpin) flagellum caused by failure to remove huge residual cytoplasmic droplets. Bent flagellum is one of the most common disorders in sperm shaping and movement in male infertile patients. Our further study will open a new window to understanding the mechanism of bent flagellum and it's medical treatment.

Academic Significance and Societal Importance of the Research Achievements

頭部離断精子(DDS)は死滅と診断され治療に使われないが、Odf2遺伝子のハプロ不全が原因のDDSは、精子頸部-中間部間で断裂する新しく発見したタイプのDDSであり顕微授精によって治療できる。ヒトにおいてOdf2-DDSが診断できれば、離断した精子を使うことで治療の道が開けることを明らかにした。Odf4遺伝子欠損マウスの精子は、不妊患者でもよく観察される尾部の屈曲変形（ヘアピン鞭毛）を示す。現在、屈曲変形の生じる詳細なメカニズムを解析中であり、その情報は生殖補助医療に活用できると考えられる。

Research Products

• [Journal Article] Recombinant thrombomodulin attenuates hyper-inflammation and glycocalyx damage in a murine model of Streptococcus pneumoniae?induced sepsis (2022)
  • Author(s): Watanabe Eizo、Akamatsu Toshinobu、Ohmori Masaaki、Kato Mayu、Takeuchi Noriko、Ishiwada Naruhiko、Nishimura Rintaro、Hishiki Haruka、Fujimura Lisa、Ito Chizuru、Hatano Masahiko
  • Journal Title: Cytokine Volume: 149 Pages: 155723-155723
  • DOI: 10.1016/j.cyto.2021.155723
  • Peer Reviewed / Open Access
• [Journal Article] Decrease of lysyl hydroxylase 2 activity causes abnormal collagen molecular phenotypes, defective mineralization and compromised mechanical properties of bone (2022)
  • Author(s): Saito T, Terajima M, Taga Y, Hayashi F, Oshima S, Kasamatsu A, Okubo Y, Ito C, Toshimori K Sunohara M, Tanzawa H, Uzawa K, Yamauchi M
  • Journal Title: Bone Volume: 154 Pages: 116242-116242
  • Peer Reviewed / Open Access
• [Journal Article] Dlec1 is required for spermatogenesis and male fertility in mice. (2020)
  • Author(s): Okitsu Y, Nagano M, Yamagata T, Ito C, Toshimori K, Dohra H, Fujii W, Yogo K.
  • Journal Title: Sci Rep Volume: 10 Issue: 1 Pages: 18883-18883
  • DOI: 10.1038/s41598-020-75957-y
  • NAID: 120006901657
  • Peer Reviewed / Open Access
• [Journal Article] Successful pregnancy and delivery achieved following intracytoplasmic sperm injection using teratozoospermic sperm exhibiting marked dysplasia of the fibrous sheath: a case report (2020)
  • Author(s): Masato Saito, Takayuki Tatsumi, Takashi Nakasuji, Megumi Ibayashi, Tatsuya Harada, Tohru Mutoh, Chizuru Ito, Akira Komiya, Kenichiro Hiraoka1, Kiyotaka Kawai
  • Journal Title: Translational Andrology and Urology Volume: 9 Issue: 2 Pages: 800-806
  • DOI: 10.21037/tau.2019.12.14
  • Peer Reviewed / Open Access
• [Journal Article] Cleavage of SPACA1 regulates assembly of sperm?egg membrane fusion machinery in mature spermatozoa† (2019)
  • Author(s): Yamatoya Kenji、Kousaka Marika、Ito Chizuru、Nakata Kazuya、Hatano Masahiko、Araki Yoshihiko、Toshimori Kiyotaka
  • Journal Title: Biology of Reproduction Volume: 102 Issue: 3 Pages: 750-757
  • DOI: 10.1093/biolre/ioz223
  • Peer Reviewed / Open Access
• [Journal Article] Odf2 haploinsufficiency causes a new type of decapitated and decaudated spermatozoa, Odf2-DDS, in mice. (2019)
  • Author(s): Ito C, Akutsu H, Yao R, Yoshida K, Yamatoya K, Mutoh T, Makino T, Aoyama K, Ishikawa H, Kunimoto K, Tsukita S, Noda T, Kikkawa M, Toshimori K.
  • Journal Title: Sci Rep. Volume: 9 Issue: 1 Pages: 14249-14249
  • DOI: 10.1038/s41598-019-50516-2
  • Peer Reviewed / Open Access
• [Journal Article] Usp26 mutation in mice leads to defective spermatogenesis depending on genetic background. (2019)
  • Author(s): Sakai K, Ito C, Wakabayashi M, Kanzaki S, Ito T, Takada S, Toshimori K, Sekita Y, Kimura T.
  • Journal Title: Sci Rep. Volume: 9 Issue: 1 Pages: 13757-13757
  • DOI: 10.1038/s41598-019-50318-6
  • Peer Reviewed / Open Access
• [Journal Article] Dephosphorylation of protamine 2 at serine 56 is crucial for murine sperm maturation in vivo (2019)
  • Author(s): Itoh Katsuhiko、Kondoh Gen、Miyachi Hitoshi、Sugai Manabu、Kaneko Yoshiyuki、Kitano Satsuki、Watanabe Hitomi、Maeda Ryota、Imura Akihiro、Liu Yu、Ito Chizuru、Itohara Shigeyoshi、Toshimori Kiyotaka、Fujita Jun
  • Journal Title: Science Signaling Volume: 12 Issue: 574 Pages: 7232-7234
  • DOI: 10.1126/scisignal.aao7232
  • Peer Reviewed / Open Access
• [Journal Article] Deficiency of lysyl hydroxylase 2 in mice causes systemic endoplasmic reticulum stress leading to early embryonic lethality (2019)
  • Author(s): 笠松厚志
  • Journal Title: Biochemical and Biophysical Research Communications Volume: 512 Issue: 3 Pages: 486-491
  • DOI: 10.1016/j.bbrc.2019.03.091
  • Peer Reviewed / Open Access
• [Journal Article] Function of the sperm acrosomal EQUATORIN protein analyzed using genetically modified mice. (2019)
  • Author(s): Toshimori K, Ito C.
  • Journal Title: J Mamm Ova Res. Volume: 36 Pages: 71-77
  • NAID: 40022068544
  • Peer Reviewed
• [Presentation] Odf2 haploinsufficiency cases a new type of decapitated and decudated spermatozoa, Odf2-DDS, in mice. (2021)
  • Author(s): Ito C, Akutsu H, YoshidaK, Yamatoya K, Mutoh T, Aoyama K, Ishikawa H, Kunimoto K, Tsukita S, Noda T, Kikkawa M, Toshimori K
  • Organizer: Proceedings of the 126th Annual Meeting of The Japanese Association of Anatomists and the 98th Annual Meeting of The Physiological Society of Japan.
• [Presentation] Usp26欠損マウスにおける遺伝的背景に依存した精子形成異常 (2019)
  • Author(s): 酒井皓平、伊藤千鶴、若林美月、神崎理子、伊藤駿瑛、高田修治、年森清隆、関田洋一、木村透
  • Organizer: 第42回日本分子生物学会年会
• [Presentation] Odf2-DDS (decapitated and decaudated spermatozoa)の原因はOdf2ハプロ不全である (2019)
  • Author(s): 伊藤千鶴、年森清隆
  • Organizer: 第64回日本生殖医学会学術講演会・総会
• [Presentation] 新しいdecapitated and decaudated spermatozoa (DDS), Odf2の発見 (2019)
  • Author(s): 年森清隆、伊藤千鶴
  • Organizer: 第64回日本生殖医学会学術講演会・総会
• [Presentation] Role of the acrosome membrane protein, Equatorin in fertilization. (2019)
  • Author(s): Ito C, Toshimori K.
  • Organizer: The 19th Congress of the International Federation of Association of Anatomists (IFAA 2019)
  • Int'l Joint Research
• [Presentation] EQUATORIN/SPESP1-double knockout mice reduce male fertility with aberrant behavior of IZUMO1. (2019)
  • Author(s): Toshimori K, Ito C.
  • Organizer: The 19th Congress of the International Federation of Association of Anatomists (IFAA 2019)
  • Int'l Joint Research
• [Presentation] 尾部形態異常精子を使用した顕微授精により分娩に至った一例 (2019)
  • Author(s): 齋藤雅人、辰巳嵩征、中筋貴史、伊林恵美、原田竜也、武藤透、伊藤千鶴、小宮顕、平岡謙一郎、川井清考
  • Organizer: 第37回日本受精着床学会総会・学術講演会
• [Presentation] 抗先体後部鞘抗体MN13を使った新しい精子機能評価法 (2019)
  • Author(s): 伊藤千鶴、年森清隆
  • Organizer: 第124回日本解剖学会総会・学術集会
• [Presentation] 抗先体後部鞘抗体EQUATORIN / SPESP1 ダブルノックアウト雄マウスの妊孕能力の減少 (2019)
  • Author(s): 年森清隆、伊藤千鶴、大和屋健二、吉田恵一、藤村理紗、幡野雅彦、宮戸健二
  • Organizer: 第124回日本解剖学会総会・学術集会
• [Book] Ross組織学 原著第7版（Histlogy. A text and atlas, with correlated cell and molecular biology. seventh edition.） (2019)
  • Author(s): 年森清隆、伊藤千鶴、若山友彦、(内山安男、相磯貞和 監訳）
  • Total Pages: 1006
  • Publisher: 南江堂
  • ISBN: 9784524259298
• [Remarks]
  • URL: https://www.m.chiba-u.jp/dept/funcanatomy/
• [Remarks] 千葉大学医学研究院 機能形態学HP
  • URL: http://www.m.chiba-u.ac.jp/class/anat2/
• [Remarks] 千葉大学医学研究院 機能形態学
  • URL: https://www.m.chiba-u.ac.jp/class/anat2/
• [Remarks] Odf2遺伝子欠損によるマウス不妊症を世界で初めて発見し治療に成功 ヒトでの応用に期待
  • URL: http://www.chiba-u.ac.jp/general/publicity/press/files/2019/20191018idenshi.pdf
• [Remarks] 世界初、Odf2遺伝子欠損による不妊症をマウスで発見、治療に成功-千葉大
  • URL: http://www.qlifepro.com/news/20191023/odf2-gene-deficiency.html