Evasion mechanisms from insect cellular immunity by nematodes

• Project/Area Number: 18K05676
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 39050:Insect science-related
• Research Institution: Saga University
• Principal Investigator: Yoshiga Toyoshi 佐賀大学, 農学部, 准教授 (00312231)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2020: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2018: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
• Keywords: 自然免疫 / 昆虫 / 線虫 / 血球 / 包囲反応 / 細胞性免疫 / spreading / 生体防御 / 免疫 / 寄生虫 / 包囲

Outline of Final Research Achievements

The evasion mechanism of nematodes from insect cellular immunity was studied. Immune suppressive factor from nematodes was partially isolated. The similar factor was detected not only from insect pathogenic nematodes but also from non-parasitic nematodes. Injection of the Caenorhabditis elegans nematode into the Galleria mellonella insect larvae resulted in the decrease of hemocyte number, which was caused by feeding of hemocytes by the nematode.

Academic Significance and Societal Importance of the Research Achievements

動物に寄生する線虫が寄生を成立させるためには宿主免疫を回避する必要がある。しかし、線虫による免疫回避機構やその進化は不明な点が多い。そこで、昆虫を宿主として用い、線虫が細胞性免疫を回避する機構の解明を試みた。線虫から抽出した体表面物質の脂質様物質が細胞の活性化を阻害することで免疫からの回避にはたらいていることが明らかとなった。また、細菌食性線虫は昆虫体内で血球を摂食し、それによって血球数が減少することも明らかとなった。さらに線虫と昆虫血球の相互作用を観察するための実験方法を確立した。

Research Products

• [Journal Article] The suppressive effect of bacterial-feeding nematodes on hemocyte spreading of Galleria mellonella. (2021)
  • Author(s): Ono, M., Hayakawa, Y., Hama, Y., Yoshiga, T.
  • Journal Title: Microbial Pathogenesis Volume: 153 Pages: 104742-104742
  • DOI: 10.1016/j.micpath.2021.104742
  • Peer Reviewed
• [Journal Article] Abnormal increases in reactive oxygen species in dying insects infected with nematodes. (2021)
  • Author(s): Tonogawa U, Matsumura T, Ono M, Yoshiga T
  • Journal Title: Arch Insect Biochem Physiol. Volume: - Issue: 2
  • DOI: 10.1002/arch.21758
  • Peer Reviewed
• [Journal Article] Mermithid nematodes isolated from the shield bug <i>Parastrachia japonensi</i><i>s </i> (2020)
  • Author(s): Iryu T, Tanaka R, Yoshiga T
  • Journal Title: Nematological Research (Japanese Journal of Nematology) Volume: 50 Issue: 1 Pages: 1-7
  • DOI: 10.3725/jjn.50.1
  • NAID: 130007966680
  • ISSN: 0919-6765, 1882-3408
  • Year and Date: 2020-09-20
  • Peer Reviewed
• [Journal Article] Comparison of cellular encapsulation with nematodes in two lepidopteran insects. (2020)
  • Author(s): Ono M, Arimatsu C, Kakinoki A, Matsunaga K, Yoshiga T.
  • Journal Title: Applied Entomology and Zoology Volume: 55 Issue: 3 Pages: 337-344
  • DOI: 10.1007/s13355-020-00687-6
  • NAID: 40022307254
  • Peer Reviewed
• [Journal Article] Bacterial feeding nematodes ingest haemocytes in the haemocoel of the insect Galleria mellonella. (2020)
  • Author(s): Ono, M. Hayakawa, Y. and Yoshiga, T.
  • Journal Title: Parasitology Volume: 147 Issue: 1 Pages: 279-286
  • DOI: 10.1007/s13355-019-00654-w
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Cellular immunity in the insect Galleria mellonella against insect non-parasitic nematodes (2020)
  • Author(s): Ono, M. and Yoshiga, T.
  • Journal Title: Parasitology Volume: 146 Issue: 6 Pages: 708-715
  • DOI: 10.1017/s003118201800210x
  • Peer Reviewed
• [Journal Article] Ex vivo observation of insect hemocyte behavior against beads and nematodes in the presence of insect plasma. (2020)
  • Author(s): Ono, M. Arimatsu, C. and Yoshiga, T.
  • Journal Title: Applied Entomology and Zoology. Volume: 55 Issue: 3 Pages: 65-70
  • DOI: 10.1017/s0031182019001550
  • NAID: 40022153360
  • Peer Reviewed
• [Presentation] ２種のチョウ目昆虫の線虫に対する包囲化 (2020)
  • Author(s): 小野雅弥・有松知里・吉賀豊司
  • Organizer: 第64回日本応用動物昆虫学会大会
• [Presentation] 非寄生性線虫は昆虫血球の活性化を遅らせる (2019)
  • Author(s): 小野 雅弥・早川 洋一・吉賀 豊司
  • Organizer: 第27回日本線虫学会大会
• [Presentation] Effects of bacterial feeding nematodes on hemocytes after injection into the hemocoel of the insect Galleria mellonella (2019)
  • Author(s): Ono, M; Hayakawa, Y; Yoshiga, T.
  • Organizer: 52nd Annual Meeting of the Society for Invertebrate Pathology
  • Int'l Joint Research
• [Presentation] Caenorhabditis elegas preys on hemocytes in the insect Gelleria mellonella (2018)
  • Author(s): Masaya Ono, Yoichi Hayakawa and Toyoshi Yoshiga
  • Organizer: European Society of Nematologists
  • Int'l Joint Research
• [Presentation] 非寄生性線虫によるチョウ目昆虫の死亡原因の解明 (2018)
  • Author(s): 小野雅弥・早川洋一・吉賀豊司
  • Organizer: 日本線虫学会
• [Presentation] 自活性線虫Caenorhabditis elegansによる昆虫の包囲化回避機構の解明 (2018)
  • Author(s): 小野雅弥・早川洋一・吉賀豊司
  • Organizer: 昆虫病理研究会