Kyushu University Academic Staff Educational and Research Activities Database
List of Presentations
Takahiro Nagasawa Last modified date:2019.06.13

Assistant Professor / Department of Bioscience and Biotechnology / Faculty of Agriculture


Presentations
1. Masayuki Nakamura, Keisuke Kondo,Takahiro Nagasawa and Reproductive Management Committee for Sand Tiger Sharks, Activity of Reproductive Management Committee for Sand Tiger Sharks, International workshop of Sand Tiger Sharks, 2018.09.
2. Takahiro Nagasawa, Tomonori Somamoto, and Miki Nakao, TLR-MEDIATED TYPE-I INTERFERON PRODUCTION AND THE REGULATORY MECHANISMS IN CARP THROMBOCYTES, International conference on Fish & Shellfish Immunology 2019, 2019.06.
3. Masaki Sukeda, Koumei Shiota, Takahiro Nagasawa, Miki Nakao, Tomonori Somamoto, Direct cytotoxic activity of CD8+ T cells against Ichthyophthirius multifiliis in ginbuna crucian carp, Carassius auratus langsdorfii, International conference on Fish & Shellfish Immunology 2019, 2019.06.
4. Masayuki Nakamura, Keisuke Kondo,Takahiro Nagasawa and Reproductive Management Committee for Sand Tiger Sharks, Activity of Reproductive Management Committee for Sand Tiger Sharks, 10th Intenational Aquarium Congress 2018 Fukushima Japan , 2018.11, Reproductive Management Committee for Sand Tiger Sharks (RMCS) is working with six aquariums to exchange rearing record since 2015. In RMCS, under different water temperature and photoperiod condition, male breeding behavior is observed in different season, spring (seasonal change) and autumn (constant). MARINEWORLD started to analyze changes in blood levels of steroid hormones(17-β-Estradiol, Progesteron, Teststeron) since 2015. Many investigations are still undergoing to reveal a mechanism of reproduction of C. taurus and to make a success in breeding of this shark in the future. Sand tiger sharks are distributed around Ogasawara islands in Japan, but biological and ecological data of them is very limited. We started data collection program (photo identification survey) in cooperation with local diving services to complement the lack of data..
5. Miki Nakao, Sayo Iwanaga, Takahiro Nagasawa, Tomonori Somamoto, Functional analysis of the classical activation pathway in teleost fish complement system: an evolutionary implication., Asian invertebrate immunity symposium 2018, 2018.09.
6. Takahiro Nagasawa, Tomonori Somamoto, Miki Nakao, Type I IFN production by carp thrombocytes as professional antiviral leukocytes, like mammalian plasmacytoid dendritic cells, via IRF7 signaling pathway., Asian invertebrate immunity symposium 2018, 2018.09, In early stage of viral infection, viral-specific nucleic acids including single/double-stranded RNA (ss/dsRNA) are recognized by innate pattern recognition receptors, such as Toll-like receptors (TLRs), thereby type-I interferon (IFN) is produced. In mammal, plasmacytoid dendritic cells are known as professional type-I IFN producing cells against viral infection, which possess interferon-regulatory factor 7 (IRF7) signaling pathway to produce huge amount of the IFN. In the present study, we show that thrombocytes in common carp (Cyprinus carpio) have potent ability to produce type-I IFN in response to synthetic viral molecule mimicries. Magnetic-sorted mAb+ thrombocytes and other peripheral blood leukocytes (PBLs) were incubated with polyinosinic:polycytidylic acid (poly(I:C), analog of dsRNA), resiquimod (R-848, ligand of TLR7/8 which detect ssRNA), or CpG motif oligodeoxynucleotides (ODN2007 and GpC motif nucleotides for control). qPCR analysis showed that thrombocytes had produced large amount of type-I IFN (ccIFNαβ) compared with the PBL fraction. R-848 acutely activated the IFN production in both fractions, whereas upregulating of the IFN expression by poly(I:C) were detected only in the PBL fractions. CpG DNA never enhanced type-I IFN expression but upregulated several inflammatory cytokines such as interleukin-6, suggesting that different signal pathways were activated by those ligand recognitions. After the R-848 stimulation, expression level of IRF7 were dramatically increased in thrombocytes, suggesting that thrombocytes activated the IRF7 signaling pathway for the IFN production. Those pattern-recognition characteristics, type-I IFN producing ability, and existence of the specialized IFN-producing pathway of carp thrombocytes are analogous to those of mammalian plasmacytoid dendritic cells, indicating that thrombocytes are important components for antiviral immunity in bony fish and can be a new target for the strategy of vaccine development..
7. Takahiro Nagasawa, Tomonori Somamoto, Miki Nakao, VIRAL LIGANDS RECOGNITION OF CARP THROMBOCYTES AS NATURAL TYPE I INTERFERON PRODUCING CELLS., 14th congress of International Society of Developmental and Comparative Immunology, 2018.06, In early stage of viral infection, viral-specific nucleic acids including single/double-stranded RNA (ss/dsRNA) are recognized by innate pattern recognition receptors, such as Toll-like receptors (TLRs), thereby type I interferon (IFN) is produced. In the present study, we report that thrombocytes in common carp (Cyprinus carpio) have potent ability to produce type I IFN in response to synthetic viral molecule mimicries. Magnetic-sorted mAb+ thrombocytes and other peripheral blood leukocytes (PBLs) were incubated with polyinosinic:polycytidylic acid (poly(I:C), an analog of dsRNA), resiquimod (R-848, an agonist of TLR7/8 which detect ssRNA), or CpG motif oligodeoxynucleotides. qPCR analysis showed that thrombocytes had produced large amount of type-I IFN compared with the PBL fraction. R-848 acutely activated the IFN production in both fractions, whereas increasing of the IFN expression by poly(I:C) were detected only in the PBL fractions. CpG DNA never induced type-I IFN expression but upregulated several inflammatory cytokines such as IL-6, suggesting that different signal pathways were activated by those ligand recognitions. After the R-848 stimulation, expression level of interferon-regulatory factor 7 (IRF7) were drastically increased in thrombocytes, suggesting that thrombocytes activated the IRF7-signal pathway to produce the IFN. Those pattern-recognition characteristics, type-I IFN producing capacity, and existence of the specialized IFN-producing pathway of carp thrombocytes are analogous to those of mammalian plasmacytoid dendritic cells, which are specialized leukocytes against viral infection, indicating that thrombocytes are important components for antiviral immunity in bony fish and can be a new target for the strategy of vaccine development..
8. Miki nakao, Sayo Iwanaga, Takahiro Nagasawa, Tomonori Somamoto, PHYLOGENETIC INFERENCE ON FUNCTIONS OF THE CLASSICAL COMPLEMENT PATHWAY IN BONY FISH, 14th congress of International Society of Developmental and Comparative Immunology, 2018.06.
9. 長澤 貴宏, 杣本智軌, 中尾 実樹, Ligand recognition specificity of carp thrombocytes as the natural type I IFN producing cells., The JSFS 85th Anniversary-Commemorative International Symposium「Fisheries Science for Future Generations, 2017.09.
10. Harsha Prakash, Shiori Motobe, Takahiro Nagasawa, Tomonori Somamoto, Miki Nakao, Functional analysis of tecrem, a CD46-like complement regulatory protein, on epithelial cells in the common carp, The JSFS 85th Anniversary-Commemorative International Symposium「Fisheries Science for Future Generations, 2017.09.
11. 長澤 貴宏, 杣本 智軌, 中尾 実樹, Phagocytosis by carp thrombocyte needs activation factors secreted from other leukocytes population, 13th congress of International Society of Developmental and Comparative Immunology, 2015.06.
12. 長澤 貴宏, 中尾 実樹, 杣本 智軌, 中易 千早, Aja M. Rieger, Daniel R. Barreda, Phagocytosis and bactericidal abilities of teleost thrombocytes., 12th congress of International Society of Developmental and Comparative Immunology, 2012.06.
13. 長澤 貴宏, Phagocytic activities of carp (Cyprinus carpio ) thrombocytes, Comparative Immunology and Pathology Workshop, 2011.05.