Host recognition of a parasite monogenean parasite Heterobothrium okamotoi for fugu Takifugu rubripes

• Project/Area Number: 26450267
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Aquatic bioproduction science
• Research Institution: Kitasato University
• Principal Investigator: Tsutsui Shigeyuki 北里大学, 海洋生命科学部, 講師 (20406911)
• Co-Investigator(Kenkyū-buntansha): 末武 弘章 福井県立大学, 海洋生物資源学部, 准教授 (00334326) ; 細谷 将 東京大学, 大学院農学生命科学研究科(農学部), 助教 (60526466) ; 田角 聡志 東京大学, 大学院農学生命科学研究科(農学部), 特任助教 (90359646)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000); Fiscal Year 2016: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2015: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2014: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: 寄生虫 / 宿主認識 / 粘液 / 抗体 / IgM / マンノース / トラフグ / 寄生 / 脱繊毛

Outline of Final Research Achievements

Fish ectoparasites make initial contact with their hosts at body surfaces, which are covered with mucosa. Fish are the most primitive vertebrates with adaptive immunity and produce and secrete IgM into mucus. In this study, we showed that a parasite Heterobothrium okamotoi utilizes IgM to recognize their host, fugu Takifugu rubripes. Oncomiracidia of H. okamotoi shed their cilia when exposed to purified mannose-binding fractions from fugu mucus. By LC-MS/MS, proteins contained in the fraction were identified as IgM and two lectins. However, although deciliation was significantly induced by the IgM and was inhibited by mannose or a specific antibody against fugu IgM, other lectins had no effect. Immunostaining showed that fugu mannose-specific IgM binds ciliated epidermal cells of oncomiracidium. Moreover, concentrations of mannose-binding IgM in gill mucus were sufficient to induce deciliation in vitro, indicating that the parasites initially use host antibodies to colonize host gills.

Research Products

• [Journal Article] Mucosal IgM antibody with d-Mannose affinity in fugu Takifugu rubripes is utilized by a monogenean parasite Heterobothrium okamotoi for host recognition. (2017)
  • Author(s): Igarashi K, Matsunaga R, Hirakawa S, Hosoya S, Suetake H, Kikuchi K, Suzuki Y, Nakamura O, Miyadai T, Tasumi S, Tsutsui S.
  • Journal Title: J Immunol Volume: in press Pages: 4107-4114
  • DOI: 10.4049/jimmunol.1601996
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] ヘテロボツリウム幼生は トラフグのマンノース結合IgMを利用し、宿主を認識する (2016)
  • Author(s): 五十嵐健斗・平河早智・細谷将・末武弘章・菊池潔・ 田角聡志・鈴木譲・宮台俊明・中村修・筒井繁行
  • Organizer: 日本水産学会
  • Place of Presentation: 東京海洋大学 東京都港区
  • Year and Date: 2016-03-26
• [Presentation] トラフグマンノース結合 IgM はヘテロボツリウム幼生の脱繊毛を誘導する (2015)
  • Author(s): 五十嵐健斗・平河早智・細谷将・末武弘章・菊池潔・中村修・宮台俊明・鈴木譲・ 田角聡志・筒井繁行
  • Organizer: 日本比較免疫学会
  • Place of Presentation: 小浜市働く婦人の家 福井県小浜市
  • Year and Date: 2015-08-21