Studies on the mechanism of the immunosuppression caused by bovine mycoplasmosis and the development of a novel control method

• Project/Area Number: 18J13237
• Research Category: Grant-in-Aid for JSPS Fellows
• Allocation Type: Single-year Grants
• Section: 国内
• Research Field: Veterinary medical science
• Research Institution: Hokkaido University
• Principal Investigator: 後藤 伸也 北海道大学, 獣医学研究科, 特別研究員(DC2)
• Project Period (FY): 2018-04-25 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥2,100,000 (Direct Cost: ¥2,100,000); Fiscal Year 2019: ¥1,000,000 (Direct Cost: ¥1,000,000); Fiscal Year 2018: ¥1,100,000 (Direct Cost: ¥1,100,000)
• Keywords: マイコプラズマ感染症 / 慢性感染症 / 免疫抑制 / 免疫チェックポイント / PD-1 / PD-L1 / 抗体医療 / プロスタグランジンE2

Outline of Annual Research Achievements

牛マイコプラズマ感染症、特にMycoplsama bovis(Mb)感染症は発症すると極めて慢性で難治性に経過する。これまでに報告者らは、Programmed death (PD)-1/PD-ligand 1 (L1)経路（PD-1経路）が本症の免疫抑制に関与し、さらにPD-1経路阻害がMb特異的免疫応答の再活性化することを示した。本研究では新規治療法の開発を最終目標に、本症の免疫抑制機序の解明とPD-L1経路を標的とした治療用抗体の治療効果の検討を行う。
報告者らは前年度、本症におけるPD-L1発現にはプロスタグランジンE2（PGE2）が関与することを示したが、PGE2の産生機序は未だ不明のままであった。そこでToll様受容体(TLR)に着目し、本症におけるPGE2産生機序の解明を試みた。健康牛由来末梢血単核球（PBMC）とMb抗原またはTLR2作動薬をTLR2拮抗薬存在下で培養し、上清中のPGE2濃度を測定した。その結果、TLR2拮抗薬存在下でPGE2産生の抑制が認められ、MbはTLR2を介してしてPGE2産生を誘導し、PD-L1発現を上昇させていることが示唆された。
前年度の研究により、治療用抗PD-L1抗体が生体内でも抗Mb免疫を再活性化することが明らかとなった。本年度は治療用抗体の治療効果のさらなる検討を行うため、肺炎症状を呈したMb感染牛を用いて、治療用抗体とPGE2阻害剤であるCOX-2阻害剤の併用投与を行った。免疫再活性化能は、Mb抗原に対するIFN-γ産生能を評価した。その結果、併用投与牛ではIFN-γ産生量の増加が認められ、試験終了時まで高い値を維持していた。以上より本症への治療用抗体の治療応用において、COX-2阻害剤の併用が生体内における免疫再活性化に有効であることが考えられ、本療法がMb感染症の新たな治療戦略となりうることが示唆された。

Research Progress Status

令和元年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

令和元年度が最終年度であるため、記入しない。

Research Products

• [Int'l Joint Research] リオグランデ・ド・スル連邦大学(ブラジル)
• [Journal Article] Upregulation of PD-L1 Expression by Prostaglandin E2 and the Enhancement of IFN-γ by Anti-PD-L1 Antibody Combined With a COX-2 Inhibitor in Mycoplasma bovis Infection (2020)
  • Author(s): Goto Shinya、Konnai Satoru、Hirano Yuki、Kohara Junko、Okagawa Tomohiro、Maekawa Naoya、Sajiki Yamato、Watari Kei、Minato Erina、Kobayashi Atsuhi、et al.
  • Journal Title: Frontiers in Veterinary Science Volume: 7 Pages: 12-12
  • DOI: 10.3389/fvets.2020.00012
  • Peer Reviewed / Open Access
• [Journal Article] Clinical efficacy of the combined treatment of anti-PD-L1 rat-bovine chimeric antibody with a COX-2 inhibitor in calves infected with Mycoplasma bovis. (2020)
  • Author(s): Goto S, Konnai S, Hirano H, Kohara J, Okagawa T, Maekawa N, Sajiki Y, Watari K, Minato E, Kobayashi A, Gondaira S, Higuchi H, Koiwa M, Tajima M, Taguchi E, Uemura R, Yamada S, Kaneko MK, Kato Y, Yamamoto K, Toda M, Suzuki Y, Murata S, Ohashi K.
  • Journal Title: Jpn J Vet Res Volume: -
  • Peer Reviewed / Open Access
• [Journal Article] Prostaglandin E2 Induced Immune Exhaustion and Enhancement of Antiviral Effects by Anti-PD-L1 Antibody Combined with COX-2 Inhibitor in Bovine Leukemia Virus Infection (2019)
  • Author(s): Sajiki Yamato、Konnai Satoru、Okagawa Tomohiro、Nishimori Asami、Maekawa Naoya、Goto Shinya、Watari Kei、Minato Erina、Kobayashi Atsushi、et al.
  • Journal Title: The Journal of Immunology Volume: 203 Issue: 5 Pages: 1313-1324
  • DOI: 10.4049/jimmunol.1900342
  • Peer Reviewed / Open Access
• [Journal Article] Prostaglandin E2 induction suppresses the Th1 immune responses in cattle with Johne's disease. (2018)
  • Author(s): Sajiki Y, Konnai S, Okagawa T, Nishimori A, Maekawa N, Goto S, Ikebuchi R, Nagata R, Kawaji S, Kagawa Y, Yamada S, Kato Y, Nakajima C, Suzuki Y, Murata S, Mori Y, Ohashi K.
  • Journal Title: Infect. Immun. Volume: in press Issue: 5
  • DOI: 10.1128/iai.00910-17
  • Peer Reviewed
• [Journal Article] Cooperation of PD-1 and LAG-3 in the exhaustion of CD4+ and CD8+ T cells during bovine leukemia virus infection (2018)
  • Author(s): Okagawa Tomohiro、Konnai Satoru、Nishimori Asami、Maekawa Naoya、Goto Shinya、Ikebuchi Ryoyo、Kohara Junko、Suzuki Yasuhiko、Yamada Shinji、Kato Yukinari、Murata Shiro、Ohashi Kazuhiko
  • Journal Title: Veterinary Research Volume: 49 Issue: 1 Pages: 50-50
  • DOI: 10.1186/s13567-018-0543-9
  • Peer Reviewed / Open Access
• [Presentation] Mycoplasma bovis感染症に対する抗PD-L1キメラ抗体を用いた臨床試験 (2019)
  • Author(s): 後藤伸也、今内覚、岡川朋宏、前川直也、小原潤子、平野佑気、鈴木定彦、加藤幸成、村田史郎、大橋和彦
  • Organizer: 第162回日本獣医学会学術集会
• [Presentation] The induction of immunosuppression via prostaglandin E2 and the enhancement of anti-bacterial effects by anti-PD-L1 antibody combined with COX-2 inhibitor in Mycoplasma bovis infection (2019)
  • Author(s): Goto S, Satoru K, Okagawa T, Maekawa N, Sajiki Y, Murata S, Ohashi K
  • Organizer: The 12th International Veterinary Immunology Symposium
  • Int'l Joint Research
• [Presentation] The enhancement of anti-bacterial effects by anti-PD-L1 antibody in Mycoplasma bovis infection (2019)
  • Author(s): Goto S, Satoru K, Okagawa T, Maekawa N, Suzuki Y, Murata S, Ohashi K
  • Organizer: The 7th Sapporo Summer Symposium for One Health
  • Int'l Joint Research
• [Presentation] Myocplasma bovis感染症におけるプロスタグランジンE2の解析 (2018)
  • Author(s): 後藤伸也、今内覚、岡川朋弘、前川直也、佐治木大和、渡慧、樋口豪紀、小岩政照、田島誉士、小原潤子、加藤幸成、鈴木定彦、村田史郎、大橋和彦
  • Organizer: 第161回日本獣医学会学術集会
• [Presentation] ウシCytotoxic T-lymphocyte antigen-4(CTLA-4)の機能解析および慢性感染症における発現解析 (2018)
  • Author(s): 渡慧、今内覚、岡川朋弘、前川直也、後藤伸也、佐治木大和、村田史郎、鈴木定彦、大橋和彦
  • Organizer: 第161回日本獣医学会学術集会
• [Presentation] ヨーネ病におけるプロスタグランジンE2（PGE2）動態解析及びCOX-2阻害剤の免疫活性化効果の検討 (2018)
  • Author(s): 佐治木大和、今内覚、岡川朋弘、西森朝美、前川直也、後藤伸也、永田礼子、川治聡子、森康行、村田史郎、大橋和彦
  • Organizer: 第161回日本獣医学会学術集会
• [Presentation] Analysis of immunosuppression mediated by the PD-1/PD-L1 pathway in bovine Mycoplasmosis (2018)
  • Author(s): Goto S., Satoru K., Okagawa T., Maekawa N., Sajiki Y., Gondaira S., Higuchi H., Koiwa M., Murata S., Ohashi K.
  • Organizer: The 3rd Circular of Joint Congress of the 7th Meeting of the Asian Organization for Mycoplasmology and the 45th Meeting of the Japanese Society of Mycoplasmology
  • Int'l Joint Research / Invited
• [Presentation] The PD-1/PD-L1 pathway contributes to the immunosuppression in bovine mycoplasmosis (2018)
  • Author(s): Goto S., Satoru K., Okagawa T., Asami N., Maekawa N., Higuchi H., Koiwa M., Tajima M., Kohara J., Kato Y., Suzuki Y., Murata S., Ohashi K.
  • Organizer: The 30th World Buiatrics Congress 2018
  • Int'l Joint Research
• [Presentation] Overcoming T-cell exhaustion in chronic infections of cattle: a pilot clinical study of anti-PD-1 immunotherapy in bovine leukemia virus infection (2018)
  • Author(s): Okagawa T., Konnai S., Maekawa N., Goto S., Sajiki Y., Kohara J., Kato Y., Suzuki Y., Mrata S. Ohashi K.
  • Organizer: The 30th World Buiatrics Congress 2018
  • Int'l Joint Research
• [Presentation] In vitro and clinical study on antivirus activity of an anti-PD-L1 rat-bovine chimeric antibody against bovine leukemia virus infection (2018)
  • Author(s): Maekawa N., Nishimori A., Konnai S., Okagawa T., Iebuchi R., Goto S., Sajiki Y., Suziki Y., Kohara J., Ogasawara S., Kato Y., Murata S., Ohashi k.
  • Organizer: The 30th World Buiatrics Congress 2018
  • Int'l Joint Research
• [Presentation] Prostaglandin E2 suppresses immune responses in cattle with Johne's disease (2018)
  • Author(s): Sajiki Y., Konnai S., Okagawa T., Nishimori A., Maekawa N., Goto S., Nagata R., Kawaji S., Kato Y., Suzuki Y., Murata S., Ohashi K.
  • Organizer: The 30th World Buiatrics Congress 2018
  • Int'l Joint Research
• [Presentation] Analysis of immunosuppression caused by prostaglandin E2 in bovine mycoplasmosis (2018)
  • Author(s): Goto S., Satoru K., Okagawa T., Maekawa N., Watari K., Sajiki Y., Suzuki Y., Murata S., Ohashi K.
  • Organizer: The 6th Sapporo Summer Symposium for One Health
  • Int'l Joint Research
• [Presentation] Prostaglandin E2 induction suppresses Th1 responses in cattle with Johne's disease (2018)
  • Author(s): Sajiki Y., Konnai S., Okagawa T., Nishimori A., Maekawa N., Goto S., Suzuki Y., Murata S., Ohashi K.
  • Organizer: The 6th Sapporo Summer Symposium for One Health
  • Int'l Joint Research
• [Presentation] Immunoinhibitory function of bovine CTLA-4 ant its relation to bovine leukemia virus infection (2018)
  • Author(s): Watari K., Konnai S., Okagawa T., Maekawa N., Goto S., Sajiki Y., Suzuki Y., Murata S., Ohashi K.
  • Organizer: The 6th Sapporo Summer Symposium for One Health
  • Int'l Joint Research