研究者詳細

顔写真

サヤマ　ユウスケ
佐山　勇輔
Yusuke Sayama
所属
大学院医学系研究科　医科学専攻　病理病態学講座（微生物学分野）
職名
助教
学位

  • 博士（医学）（東北大学）

  • 修士（医科学）（千葉大学）

学歴 1

  • 東北大学大学院医学系研究科

    2008年4月 ～ 2012年3月

研究分野 2

  • ライフサイエンス / 胎児医学、小児成育学 /

  • ライフサイエンス / 衛生学、公衆衛生学分野：実験系を含む /

論文 43

  1. Molecular analysis of influenza A(H3N2) in a remote tropical island during 2014-2019 to identify the frequency of introduction and local circulation

    Sikandar Azam, Takeaki Imamura, Michiko Okamoto, Yusuke Sayama, Mayuko Saito, Mariko Saito-Obata, Clyde Dapat, Raita Tamaki, Christina Dahlia Joboco, Joanna Ina Manalo, Samantha Louise Bado, Joanne De Jesus Cornejo, Socorro Lupisan, Marianette Inobaya, Veronica Tallo, Beatriz P Quiambao, Hitoshi Oshitani

    International Journal of Infectious Diseases　2025年5月

    DOI： 10.1016/j.ijid.2025.107864 　

  2. Norovirus-associated diarrhea and asymptomatic infection in children aged under 4 years: a community-cohort study in the Philippines

    Chuyao Yu, Maria Carmen A. Corpuz, Joseph M. Bonifacio, Makiko Kishi, Takeaki Imamura, Yusuke Sayama, Mariko Saito-Obata, Clyde Dapat, Michiko Okamoto, Hitoshi Oshitani, Mayuko Saito

    IJID Regions　2025年3月

    DOI： 10.1016/j.ijregi.2024.100549 　

  3. Serological analyses against endemic human coronaviruses and SARS-CoV-2 in children and adults using samples collected before the COVID-19 pandemic

    Yusuke Sayama, Chuan Lo, Hiroki Tomizawa, Mayuko Saito, Michiko Okamoto, Suguru Ohmiya, Hidekazu Nishimura, Hitoshi Oshitani

    IJID Regions　2024年12月

    DOI： 10.1016/j.ijregi.2024.100485 　

  4. Japanese encephalitis in swine in San Jose, Tarlac, Philippines

    Fedelino F. Malbas, Jr., Mariko Saito-Obata, Yusuke Sayama, Nelia P. Salazar, Wilfredo E. Aure, Hazel O. Galang, Cecille L. Zuasula, Hitoshi Oshitani

    IJID One Health　2024年12月

    DOI： 10.1016/j.ijidoh.2024.100038 　

  5. Detection of human coronavirus-OC43 in nasopharyngeal swab specimens via immunofluorescence staining using human serum and an anti-human antibody. 査読有り

    Mutsuo Yamaya, Oshi Watanabe, Yuki Kitai, Yusuke Sayama, Suguru Ohmiya, Hidekazu Nishimura

    Japanese journal of infectious diseases　2024年11月29日

    DOI： 10.7883/yoken.JJID.2024.001 　

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    Immunofluorescence methods to detect seasonal human coronavirus (HCoV)-OC43 in nasopharyngeal swab specimens using cell lines have not yet been established. A human rectal adenocarcinoma cell line (HRT-18) was exposed to the specimens obtained from patients with upper respiratory tract infections. Immunofluorescence staining was conducted with the combination of human serum containing the HCoV-OC43 anti-spike protein antibody and a fluorescence-labeled anti-human antibody. Positive staining in HRT-18 cells was detected after exposure to specimens obtained from nine of the eleven patients in which HCoV-OC43 RNA was detected using the FilmArray method. Increased supernatant viral RNA levels were also detected in HRT-18 cells exposed to specimens obtained from four of five patients. In contrast, positive staining was not detected in HRT-18 cells exposed to six patient specimens that tested negative for RNA from seventeen types and subtypes of respiratory viruses, including HCoV-OC43. The cells inoculated with the established strain HCoV-OC43 (ATCC VR-759) also showed positive staining. These findings suggest that the replication-competent HCoV-OC43 in the specimens could be detected via immunofluorescence staining of HRT-18 cells with human serum. It may be possible to obtain positive staining for viruses other than HCoV-OC43 using this method.

  6. Identification of Various Recombinants in a Patient Coinfected With the Different SARS-CoV-2 Variants. 国際誌 査読有り

    Yusuke Sayama, Akie Sakagami, Michiko Okamoto, Masahiro Sakamoto, Hikari Koizumi, Yoko Kimura, Clyde Dapat, Mayuko Saito, Yuko Suzuki, Mie Sasaki, Naoko Sugawara, Hitoshi Oshitani

    Influenza and other respiratory viruses　18　(6)　e13340　2024年6月

    DOI： 10.1111/irv.13340 　

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    BACKGROUND: Viral recombination that occurs by exchanging genetic materials between two viral genomes coinfecting the same host cells is associated with the emergence of new viruses with different virulence. Herein, we detected a patient coinfected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta and Omicron variants and identified various recombinants in the SARS-CoV-2 full-length spike gene using long-read and Sanger sequencing. METHODS: Samples from five patients in Japan with household transmission of coronavirus disease 2019 (COVID-19) were analyzed using molecular assays for detection and identification of SARS-CoV-2. Whole-genome sequencing was conducted using multiplex PCR with short-read sequencing. RESULTS: Among the five SARS-CoV-2-positive patients, the mutation-specific assay identified the Delta variant in three, the Omicron variant in one, and an undetermined in one. The undermined patient was identified as Delta using whole-genome sequencing, but samples showed a mixed population of Delta and Omicron variants. This patient was analyzed for viral quasispecies by long-read and Sanger sequencing using a full-length spike gene amplicon. In addition to the Delta and Omicron sequences, the viral quasispecies analysis identified nine different genetic recombinant sequences with various breakpoints between Delta and Omicron sequences. The nine detected recombinant sequences in the spike gene showed over 99% identity with viruses that were detected during the Delta and Omicron cocirculation period from the United States and Europe. CONCLUSIONS: This study demonstrates that patients coinfected with different SARS-CoV-2 variants can generate various viral recombinants and that various recombinant viruses may be produced during the cocirculation of different variants.

  7. Lack of zoonotic coronavirus species detected among children hospitalized with pneumonia in the Philippines. 国際誌 査読有り

    Yusuke Sayama, Michiko Okamoto, Mayuko Saito, Raita Tamaki, Mariko Saito-Obata, Reynaldo Frederick Negosa Quicho, Christina Dahlia Joboco, Socorro Lupisan, Hitoshi Oshitani

    Clinical infectious diseases : an official publication of the Infectious Diseases Society of America　77　(11)　1612-1613　2023年7月20日

    DOI： 10.1093/cid/ciad430 　

  8. Seroprevalence of four endemic human coronaviruses and, reactivity and neutralization capability against SARS-CoV-2 among children in the Philippines. 国際誌 査読有り

    Yusuke Sayama, Michiko Okamoto, Mayuko Saito, Mariko Saito-Obata, Raita Tamaki, Christine Dahlia Joboco, Socorro Lupisan, Hitoshi Oshitani

    Scientific reports　13　(1)　2310-2310　2023年2月9日

    DOI： 10.1038/s41598-023-29072-3 　

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    Four endemic human coronaviruses (HCoV), HCoV-229E, HCoV-NL63, HCoV-HKU1, and HCoV-OC43, are closely related to SARS-CoV-2. These coronaviruses are known to infect humans living in temperate areas, including children under 5 years old; however, the seroprevalence of four HCoVs among children in tropical areas, including the Philippines, remains unclear. This study aimed to assess the prevalence of antibodies against four HCoVs and to determine the reactivity and neutralization of these antibodies against SARS-CoV-2 among children in the Philippines. A total of 315 serum samples collected from 2015 to 2018, before the emergence of SARS-CoV-2, in Biliran island, Philippines, were tested for the presence of antibodies against four HCoVs and SARS-CoV-2 using recombinant spike ectodomain proteins by IgG-enzyme-linked immunosorbent assay (ELISA). Reactivity to and neutralization of SARS-CoV-2 were also investigated. The seroprevalence of the four HCoVs was 63.8% for HCoV-229E, 71.4% for HCoV-NL63, 76.5% for HCoV-HKU1, and 83.5% for HCoV-OC43 by ELISA. Age group analysis indicated that seropositivity to all HCoVs reached 80% by 2-3 years of age. While 69/315 (21.9%) of the samples showed reactive to SARS-CoV-2, almost no neutralization against SARS-CoV-2 was detected using neutralization assay. Reactivity of antibodies against SARS-CoV-2 spike protein obtained by ELISA may not correlate with neutralization capability.

  9. Comparison of Rhinovirus A-, B-, and C-Associated Respiratory Tract Illness Severity Based on the 5'-Untranslated Region Among Children Younger Than 5 Years. 国際誌 査読有り

    Akiko Sayama, Michiko Okamoto, Raita Tamaki, Mariko Saito-Obata, Mayuko Saito, Taro Kamigaki, Yusuke Sayama, Irene Lirio, Joanna Ina G Manalo, Veronica L Tallo, Socorro P Lupisan, Hitoshi Oshitani

    Open forum infectious diseases　9　(10)　ofac387　2022年10月

    DOI： 10.1093/ofid/ofac387 　

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    BACKGROUND: Rhinoviruses (RVs) are among the most frequently detected viruses from hospitalized children with severe acute respiratory infections, being classified into RV-A, RV-B, and RV-C (4 clades: C, GAC1, GAC2, and A2). This study aimed to compare the clinical characteristics and respiratory tract illness severity between the RV species and RV-C clades in children in primary care and hospital settings in rural communities in the Philippines. METHODS: Clinical samples and information of children <5 years old in the Philippines were collected from 2014 to 2016. The samples were tested by reverse-transcription polymerase chain reaction (RT-PCR) targeting the 5'-untranslated region. PCR-positive samples were sequenced, and RV species were identified by phylogenetic analysis. RESULTS: Overall, 3680 respiratory tract illness episodes in 1688 cohort children were documented; 713 of those were RV positive and identified as RV-A (n = 271), RV-B (n = 47), and RV-C (n = 395: C [n = 76], GAG1 [n = 172], GAG2 [n = 8], A2 [n = 138], and unidentified [n = 1]). Severe illnesses, low oxygen saturation, cough, and wheezing were more common in patients with RV-C, especially with GAC1, than in those with RV-A or RV-B. Furthermore, severe illness was significantly more common in RV-C (GAC1)-positive cases than in RV-A-positive cases (odds ratio, 2.61 [95% CI, 1.17-4.13]). CONCLUSIONS: Children infected with RV-C had more severe illnesses than children infected with RV-A and RV-B. Moreover, emerging clades of RV-C were associated with increased severity.

  10. Japanese encephalitis virus genotype III from mosquitoes in Tarlac, Philippines. 国際誌 査読有り

    Wilfredo E Aure, Yusuke Sayama, Mariko Saito-Obata, Nelia P Salazar, Fedelino F Malbas Jr, Hazel O Galang, Tadatsugu Imamura, Cecilia L Zuasula, Hitoshi Oshitani

    IJID regions　4　59-65　2022年9月

    DOI： 10.1016/j.ijregi.2022.05.005 　

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    OBJECTIVES: The aim of this study was to investigate the presence of Japanese encephalitis virus (JEV) in a rice-farming community in the Philippines and to determine its implications regarding the epidemiology of viral encephalitides in the Asia-Pacific Region. METHODS: Mosquitoes were collected monthly from animal-baited traps close to flooded rice fields in two barangays (villages) in the Municipality of San Jose, Tarlac Province in Luzon, from May 2009 to July 2010. Virus was detected by nested reverse transcription PCR. Phylogenetic analysis of the amplified virus envelope gene was done using the maximum-likelihood method. RESULTS: A total of 28 700 known vector mosquitoes were collected, namely Culex vishnui, Culex fuscocephala, Culex tritaeniorhynchus, and Culex gelidus. JEV genotype III was detected in C. tritaeniorhynchus, belonging to the same genotype but form a different clade from those reported in the 1980s and in 2020 in this country. CONCLUSIONS: Japanese encephalitis is associated with rice cultivation and the presence of infected mosquitoes in Tarlac, Philippines. It remains to be seen whether the observed genetic shift of genotype III to genotype I in Asia will in time have an impact on the epidemiology of Japanese encephalitis in the Philippines. For long-term disease control, regular surveillance and Japanese encephalitis immunization in children and travelers in high risk areas are recommended.

  11. Establishment of a novel anti-TROP2 monoclonal antibody TrMab-29 for immunohistochemical analysis. 国際誌 査読有り

    Yusuke Sayama, Mika K Kaneko, Junko Takei, Hideki Hosono, Masato Sano, Teizo Asano, Yukinari Kato

    Biochemistry and biophysics reports　25　100902-100902　2021年3月

    DOI： 10.1016/j.bbrep.2020.100902 　

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    TROP2 is a type I transmembrane glycoprotein originally identified in human trophoblast cells that is overexpressed in several types of cancer. To better understand the role of TROP2 in cancer, we herein aimed to develop a sensitive and specific anti-TROP2 monoclonal antibody (mAb) for use in flow cytometry, Western blot, and immunohistochemistry using a Cell-Based Immunization and Screening (CBIS) method. Two mice were immunized with N-terminal PA-tagged and C-terminal RAP/MAP-tagged TROP2-overexpressed Chinese hamster ovary (CHO)-K1 cells (CHO/PA-TROP2-RAP-MAP), and hybridomas showing strong signals from PA-tagged TROP2-overexpressed CHO-K1 cells (CHO/TROP2-PA) and weak-to-no signals from CHO-K1 cells were selected using flow cytometry. We demonstrated using flow cytometry that the established anti-TROP2 mAb, TrMab-29 (mouse IgG1 kappa), detected TROP2 in MCF7 breast cancer cell line as well as CHO/TROP2-PA cells. Western blot analysis showed a 40 kDa band in lysates prepared from both CHO/TROP2-PA and MCF7 cells. Furthermore, TROP2 was strongly detected by immunohistochemical analysis using TrMab-29, indicating that TrMab-29 may be a valuable tool for the detection of TROP2 in cancer.

  12. Development and characterization of TrMab‑6, a novel anti‑TROP2 monoclonal antibody for antigen detection in breast cancer. 国際誌 査読有り

    Yusuke Sayama, Mika K Kaneko, Yukinari Kato

    Molecular medicine reports　23　(2)　2021年2月

    DOI： 10.3892/mmr.2020.11731 　

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    Trophoblast cell‑surface antigen 2 (TROP2) is a type I transmembrane glycoprotein that is overexpressed in a number of cancer types, including triple‑negative breast cancer. The current study aimed to develop a highly sensitive and specific monoclonal antibody (mAb) targeting TROP2, which could be used to evaluate TROP2 expression using flow cytometry, western blot analysis and immunohistochemistry by employing the Cell‑Based Immunization and Screening (CBIS) method. The established anti‑TROP2 mAb, TrMab‑6 (mouse IgG2b, κ), detected TROP2 on PA‑tagged TROP2‑overexpressing Chinese hamster ovary‑K1 (CHO/TROP2‑PA) and breast cancer cell lines, including MCF7 and BT‑474 using flow cytometry. Western blot analysis indicated a 40 kDa band in lysates prepared from CHO/TROP2‑PA, MCF7 and BT‑474 cells. Furthermore, TROP2 in 57/61 (93.4%) of the breast cancer specimens was strongly detected using immunohistochemical analysis with TrMab‑6. In conclusion, the current study demonstrated that TrMab‑6 may be a valuable tool for the detection of TROP2 in a wide variety of breast cancer types.

  13. The anti-epithelial cell adhesion molecule (EpCAM) monoclonal antibody EpMab-16 exerts antitumor activity in a mouse model of colorectal adenocarcinoma. 国際誌 査読有り

    Hideki Hosono, Tomokazu Ohishi, Junko Takei, Teizo Asano, Yusuke Sayama, Manabu Kawada, Mika K Kaneko, Yukinari Kato

    Oncology letters　20　(6)　383-383　2020年12月

    DOI： 10.3892/ol.2020.12246 　

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    The epithelial cell adhesion molecule (EpCAM), which is a calcium-independent homophilic intercellular adhesion factor, contributes to cell signaling, differentiation, proliferation and migration. EpCAM is essential for carcinogenesis in numerous types of human cancer. The purpose of the present study was to establish an anti-EpCAM monoclonal antibody (mAb) for targeting colorectal adenocarcinomas. Thus, an anti-EpCAM mAb, EpMab-16 (IgG2a, κ), was established by immunizing mice with EpCAM-overexpressing CHO-K1 cells, and validated using flow cytometry, western blot, and immunohistochemical analyses. EpMab-16 reacted with endogenous EpCAM specifically in a colorectal adenocarcinoma cell line as determined by flow cytometry and western blot analyses. Immunohistochemical analysis demonstrated that EpMab-16 stained a plasma membrane-like pattern in clinical colorectal adenocarcinoma tissues. The dissociation constant (K D) for EpMab-16 in a Caco-2 colorectal adenocarcinoma cell line determined by flow cytometry was 1.8×10-8 M, suggesting moderate binding affinity of EpMab-16 for EpCAM. Whether the EpMab-16 induced antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) against Caco-2 or antitumor activity was then assessed in a murine xenograft model. In vitro experiments revealed strong ADCC and CDC induction in Caco-2 cells by EpMab-16 treatment. In vivo experiments in a Caco-2 ×enograft model demonstrated that EpMab-16 treatment significantly reduced tumor growth compared with that in mice treated with the control mouse IgG. These results suggested that EpMab-16 may be a promising treatment option for EpCAM-expressing colorectal adenocarcinomas.

  14. Anti‑EpCAM monoclonal antibody exerts antitumor activity against oral squamous cell carcinomas. 国際誌 査読有り

    Mika K Kaneko, Tomokazu Ohishi, Junko Takei, Masato Sano, Takuro Nakamura, Hideki Hosono, Miyuki Yanaka, Teizo Asano, Yusuke Sayama, Hiroyuki Harada, Manabu Kawada, Yukinari Kato

    Oncology reports　44　(6)　2517-2526　2020年12月

    DOI： 10.3892/or.2020.7808 　

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    The epithelial cell adhesion molecule (EpCAM) is a calcium‑independent, homophilic, intercellular adhesion factor classified as a transmembrane glycoprotein. In addition to cell adhesion, EpCAM also contributes to cell signaling, differentiation, proliferation, and migration. EpCAM is an essential factor in the carcinogenesis of numerous human cancers. In the present study, we developed and validated an anti‑EpCAM monoclonal antibody (mAb), EpMab‑16 (IgG2a, kappa), by immunizing mice with EpCAM‑overexpressing CHO‑K1 cells. EpMab‑16 specifically reacted with endogenous EpCAM in oral squamous cell carcinoma (OSCC) cell lines in flow cytometry and Western blot analyses. It exhibited a plasma membrane‑like stain pattern in OSCC tissues upon immunohistochemical analysis. The KD for EpMab‑16 in SAS and HSC‑2 OSCC cells were assessed via flow cytometry at 1.1x10‑8 and 1.9x10‑8 M, respectively, suggesting moderate binding affinity of EpMab‑16 for EpCAM. We then assessed whether the EpMab‑16 induced antibody‑dependent cellular cytotoxicity (ADCC) and complement‑dependent cytotoxicity (CDC) against OSCC cell lines, and antitumor capacity in a murine xenograft model. In vitro experiments revealed strong ADCC and CDC inducement against OSCC cells treated with EpMab‑16. In vivo experiments on OSCC xenografts revealed that EpMab‑16 treatment significantly reduced tumor growth compared with the control mouse IgG. These data indicated that EpMab‑16 could be a promising treatment option for EpCAM‑expressing OSCCs.

  15. A defucosylated anti‑CD44 monoclonal antibody 5‑mG2a‑f exerts antitumor effects in mouse xenograft models of oral squamous cell carcinoma. 国際誌 査読有り

    Junko Takei, Mika K Kaneko, Tomokazu Ohishi, Hideki Hosono, Takuro Nakamura, Miyuki Yanaka, Masato Sano, Teizo Asano, Yusuke Sayama, Manabu Kawada, Hiroyuki Harada, Yukinari Kato

    Oncology reports　44　(5)　1949-1960　2020年11月

    DOI： 10.3892/or.2020.7735 　

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    CD44 is widely expressed on the surface of most tissues and all hematopoietic cells, and regulates many genes associated with cell adhesion, migration, proliferation, differentiation, and survival. CD44 has also been studied as a therapeutic target in several cancers. Previously, an anti‑CD44 monoclonal antibody (mAb), C44Mab‑5 (IgG1, kappa) was established by immunizing mice with CD44‑overexpressing Chinese hamster ovary (CHO)-K1 cells. C44Mab‑5 recognized all CD44 isoforms, and showed high sensitivity for flow cytometry and immunohistochemical analysis in oral cancers. However, as the IgG1 subclass of C44Mab‑5 lacks antibody‑dependent cellular cytotoxicity (ADCC) and complement‑dependent cytotoxicity (CDC), the antitumor activity of C44Mab‑5 could not be determined. In the present study, we converted the mouse IgG1 subclass antibody C44Mab‑5 into an IgG2a subclass antibody, 5‑mG2a, and further produced a defucosylated version, 5‑mG2a‑f, using FUT8‑deficient ExpiCHO‑S (BINDS‑09) cells. Defucosylation of 5‑mG2a‑f was confirmed using fucose‑binding lectins, such as AAL and PhoSL. The dissociation constants (KD) for 5‑mG2a‑f against SAS and HSC‑2 oral cancer cells were determined through flow cytometry to be 2.8x10‑10 M and 2.6x10‑9 M, respectively, indicating that 5‑mG2a‑f possesses extremely high binding affinity. Furthermore, immunohistochemical staining using 5‑mG2a‑f specifically stained the membranes of oral cancer cells. In vitro analysis demonstrated that 5‑mG2a‑f showed moderate ADCC and CDC activities against SAS and HSC‑2 oral cancer cells. In vivo analysis revealed that 5‑mG2a‑f significantly reduced tumor development in SAS and HSC‑2 xenografts in comparison to control mouse IgG, even after injection seven days post‑tumor inoculation. Collectively, these results suggest that treatment with 5‑mG2a‑f may represent a useful therapy for patients with CD44‑expressing oral cancers.

  16. Development of Core-Fucose-Deficient Humanized and Chimeric Anti-Human Podoplanin Antibodies. 国際誌 査読有り

    Mika K Kaneko, Tomokazu Ohishi, Takuro Nakamura, Hiroyuki Inoue, Junko Takei, Masato Sano, Teizo Asano, Yusuke Sayama, Hideki Hosono, Hiroyoshi Suzuki, Manabu Kawada, Yukinari Kato

    Monoclonal antibodies in immunodiagnosis and immunotherapy　39　(5)　167-174　2020年10月

    DOI： 10.1089/mab.2020.0019 　

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    Podoplanin (PDPN), a 36-kDa type I transmembrane O-glycoprotein, is expressed in normal cells, including renal epithelial cells (podocytes), lymphatic endothelial cells, and pulmonary type I alveolar cells, and in cancer cells, including brain tumors and squamous cell lung carcinomas. PDPN activates platelet aggregation by binding to C-type lectin-like receptor-2 (CLEC-2) on platelets, and PDPN/CLEC-2 interaction facilitates blood/lymphatic vessel separation. We previously produced an anti-human PDPN monoclonal antibody (mAb), clone NZ-1 (rat IgG2a, lambda) and its rat-human chimeric mAbs (NZ-8/NZ-12), which neutralize PDPN/CLEC-2 interactions and inhibit platelet aggregation and cancer metastasis. In this study, we first developed a humanized anti-human PDPN mAb, named as NZ-27. We further produced a core-fucose-deficient version of NZ-27, named as P1027 and a core-fucose-deficient version of NZ-12, named as NZ-12f. We investigated the binding affinity, antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), and antitumor activity of P1027 and NZ-12f. We demonstrated that the binding affinities of P1027 and NZ-12f against LN319 (a human glioblastoma cell line) are 1.1 × 10-8 and 3.9 × 10-9 M, respectively. ADCC reporter assays demonstrated that NZ-12f shows 1.5 times higher luminescence than P1027. Furthermore, NZ-12f showed 2.2 times higher ADCC than P1027, whereas both P1027 and NZ-12f showed high CDC activities against LN319 cells. Using LN319 xenograft models, P1027 and NZ-12f significantly reduced tumor development in an LN319 xenograft model compared with control human IgG. Treatment with P1027 and NZ-12f may be a useful therapy for patients with PDPN-expressing cancers.

  17. Anti-EGFR monoclonal antibody 134-mg<inf>2a</inf> exerts antitumor effects in mouse xenograft models of oral squamous cell carcinoma 査読有り

    Hideki Hosono, Junko Takei, Tomokazu Ohishi, Masato Sano, Teizo Asano, Yusuke Sayama, Takuro Nakamura, Miyuki Yanaka, Manabu Kawada, Hiroyuki Harada, Mika Kato Kaneko, Yukinari Kato

    International Journal of Molecular Medicine　46　(4)　1443-1452　2020年10月

    DOI： 10.3892/ijmm.2020.4700 　

    ISSN：1107-3756

    eISSN：1791-244X

  18. An Anti-Human Epidermal Growth Factor Receptor 2 Monoclonal Antibody H2Mab-19 Exerts Antitumor Activity in Mouse Colon Cancer Xenografts 国際誌 査読有り

    Yukinari Kato, Tomokazu Ohishi, Junko Takei, Takuro Nakamura, Masato Sano, Teizo Asano, Yusuke Sayama, Hideki Hosono, Manabu Kawada, Mika K. Kaneko

    Monoclonal Antibodies in Immunodiagnosis and Immunotherapy　39　(4)　123-128　2020年8月1日

    出版者・発行元： Mary Ann Liebert Inc

    DOI： 10.1089/mab.2020.0009 　

    eISSN：2167-9436

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    The epidermal growth factor receptor (EGFR) contributes to tumor malignancy through gene amplification and/or protein overexpression. In our previous study, we developed an anti-human EGFR (hEGFR) monoclonal antibody, clone EMab-134 (mouse IgG1, kappa), which specifically detects both hEGFR and dog EGFR (dEGFR). The defucosylated mouse IgG2a version of EMab-134 (134-mG2a-f) exhibits antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) in dEGFR-overexpressed Chinese hamster ovary-K1 (CHO/dEGFR) cells and antitumor activities in mouse xenografts of CHO/dEGFR cells. In this study, the reactivity of 134-mG2a-f against a canine mammary gland tumor cell line (SNP) was examined by flow cytometry and immunocytochemistry. Furthermore, 134-mG2a-f highly exerted ADCC and CDC for SNP. The administration of 134-mG2a-f significantly suppressed the SNP xenograft growth. These results suggest that 134-mG2a-f exerts antitumor effects against dEGFR-expressing canine mammary gland tumors, and could be valuable as part of an antibody treatment regimen for them.

  19. Development and Characterization of Anti-Sheep Podoplanin Monoclonal Antibodies PMab-253 and PMab-260. 国際誌 査読有り

    Mika K Kaneko, Masato Sano, Junko Takei, Teizo Asano, Yusuke Sayama, Hideki Hosono, Atsushi Kobayashi, Satoru Konnai, Yukinari Kato

    Monoclonal antibodies in immunodiagnosis and immunotherapy　2020年7月16日

    DOI： 10.1089/mab.2020.0018 　

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    Anti-podoplanin (PDPN) monoclonal antibodies (mAbs) are needed as markers for lymphatic endothelial cells or type I alveolar cells in immunohistochemical analyses. We have developed anti-PDPN mAbs for many species, including humans, mice, rats, rabbits, dogs, cats, bovines, pigs, Tasmanian devils, alpacas, tigers, whales, goats, horses, and bears. This study develops and characterizes anti-sheep PDPN (sPDPN) mAbs using Cell-Based Immunization and Screening (CBIS) method. A RAP14 tag was added to the N-terminus of sPDPN, and an anti-RAP14 tag mAb (PMab-2) was used to measure the expression level of sPDPN in flow cytometry and Western blots. We immunized mice with sPDPN-overexpressing Chinese hamster ovary (CHO)-K1 (CHO/sPDPN) cells and screened mAbs against sPDPN using flow cytometry. Two of the mAbs, PMab-253 (immunoglobulin M [IgM], kappa) and PMab-260 (IgM, kappa), detected CHO/sPDPN cells specifically using flow cytometry and Western blots. Both PMab-253 and PMab-260 stained the renal glomerulus and Bowman's capsule, lymphatic endothelial cells of the lung and colon, and type I alveolar cells of the lung, suggesting PMab-253 and PMab-260, which were developed by CBIS method, can be applied to functional analyses of sPDPN. We also determined the binding epitope of PMab-253 and PMab-260 using flow cytometry. Analysis of sPDPN deletion mutants revealed that the N-terminus of the PMab-253 and PMab-260 epitope exists between amino acids 110 and 115 of sPDPN. Analysis of sPDPN point mutations revealed that the critical epitope of PMab-253 and PMab-260 includes Thr112 and Ser113 of sPDPN, indicating that the PMab-253 and PMab-260 epitope are independent of the platelet aggregation-stimulating (PLAG) domain or the PLAG-like domain of sPDPN.

  20. An Anti-Human Epidermal Growth Factor Receptor 2 Monoclonal Antibody H2Mab-19 Exerts Antitumor Activity in Mouse Colon Cancer Xenografts. 国際誌 査読有り

    Yukinari Kato, Tomokazu Ohishi, Junko Takei, Takuro Nakamura, Masato Sano, Teizo Asano, Yusuke Sayama, Hideki Hosono, Manabu Kawada, Mika K Kaneko

    Monoclonal antibodies in immunodiagnosis and immunotherapy　2020年6月18日

    DOI： 10.1089/mab.2020.0009 　

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    Trastuzumab is a humanized antibody against human epidermal growth factor receptor 2 (HER2) that offers significant survival benefits to patients with HER2-overexpressing breast or gastric cancer. HER2 is also known to be overexpressed in colon cancers. In this study, a novel anti-HER2 monoclonal antibody (mAb), H2Mab-19 (IgG2b, κ) was characterized for its anticancer activity in colon cancers. H2Mab-19 showed both antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity activities against Caco-2, a colon cancer cell line. Furthermore, H2Mab-19 significantly reduced tumor development in a Caco-2 xenograft model. These results suggest that treatment with H2Mab-19 may be a useful therapy for patients with HER2-expressing colon cancers.

  21. Epitope Mapping of the Anti-Diacylglycerol Kinase Monoclonal Antibody DhMab-4 for Immunohistochemical Analysis. 国際誌 査読有り

    Teizo Asano, Masato Sano, Junko Takei, Yusuke Sayama, Mika K Kaneko, Yukinari Kato

    Monoclonal antibodies in immunodiagnosis and immunotherapy　2020年6月2日

    DOI： 10.1089/mab.2020.0012 　

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    Diacylglycerol kinase (DGK) plays a pivotal role in intracellular signaling pathways in mammals. Activated G protein-coupled receptor activates phospholipase C (PLC) through heterotrimeric G protein, following which PLC hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) into diacylglycerol (DG) and inositol 1,4,5-trisphosphate (IP3). DGK catalyzes DG phosphorylation to produce phosphatidic acid. DG and phosphatidic acid function as second messengers and their intracellular concentrations are regulated by DGK; therefore, DGK plays an important role in regulating many biological processes. There are ten DGK isozymes, of which DGKη is classified as a type II DGK. Reports have shown that DGKη is associated with several diseases; for example, it is highly expressed in the hippocampus and cerebellum and is a key element in bipolar disorder. Although a DGKη-specific monoclonal antibody (mAb) is necessary to reveal the association between the expression of DGKη and diseases, an anti-DGKη mAb for immunohistochemistry has not yet been established. In this study, we established a specific anti-human DGKη (hDGKη) mAb, DhMab-4 (mouse IgG2b, kappa). DhMab-4 strongly stained Purkinje cells of human cerebellum in immunohistochemistry analysis. For epitope mapping of DhMab-4, we produced deletion or point mutants of hDGKη and performed western blotting to determine the binding epitope of DhMab-4. DhMab-4 reacted with dN745 mutant but not with dN750 mutant, indicating that the N-terminus of the DhMab-4 epitope is located between amino acids 745 and 750. More detailed analysis using point mutants demonstrated that five mutants, that is, D747A, P748A, F749A, G750A, and T752A, were not detected by DhMab-4. These results indicate that Asp747, Pro748, Phe749, Gly750, and Thr752 are important for DhMab-4 binding to hDGKη.

  22. Detection of Lion Podoplanin Using the Antitiger Podoplanin Monoclonal Antibody PMab-231

    Yukinari Kato, Junko Takei, Masato Sano, Teizo Asano, Yusuke Sayama, Kazuyuki Uchida, Takayuki Nakagawa, Mika K. Kaneko

    Monoclonal Antibodies in Immunodiagnosis and Immunotherapy　39　(3)　91-94　2020年6月1日

    出版者・発行元： Mary Ann Liebert Inc.

    DOI： 10.1089/mab.2020.0008 　

    ISSN：2167-9436

  23. Development of an Anti-Sheep Podoplanin Monoclonal Antibody PMab-256 for Immunohistochemical Analysis of Lymphatic Endothelial Cells

    Yukinari Kato, Yoshikazu Furusawa, Masato Sano, Junko Takei, Takuro Nakamura, Miyuki Yanaka, Saki Okamoto, Saori Handa, Yu Komatsu, Teizo Asano, Yusuke Sayama, Mika K. Kaneko

    Monoclonal Antibodies in Immunodiagnosis and Immunotherapy　39　(3)　82-90　2020年6月1日

    出版者・発行元： Mary Ann Liebert Inc.

    DOI： 10.1089/mab.2020.0005 　

    ISSN：2167-9436

  24. H2Mab-19 Anti-Human Epidermal Growth Factor Receptor 2 Monoclonal Antibody Therapy Exerts Antitumor Activity in Pancreatic Cancer Xenograft Models. 国際誌 査読有り

    Yukinari Kato, Tomokazu Ohishi, Masato Sano, Teizo Asano, Yusuke Sayama, Junko Takei, Manabu Kawada, Mika K Kaneko

    Monoclonal antibodies in immunodiagnosis and immunotherapy　2020年5月18日

    DOI： 10.1089/mab.2020.0011 　

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    Overexpression of human epidermal growth factor receptor 2 (HER2) has been reported in breast cancer, gastric, lung, colorectal, oral, and pancreatic cancers. HER2 expression is associated with poor clinical outcomes. An anti-HER2 humanized antibody, trastuzumab, has improved survival rates in patients with HER2-overexpressing breast and gastric cancers. Previously, we established a novel anti-HER2 monoclonal antibody (mAb), H2Mab-19 (IgG2b, kappa). It has also been characterized for breast, oral, and colon cancers. In this study, we investigated the antitumor activities of H2Mab-19 in pancreatic cancer xenograft models. We selected MIA PaCa-2, a pancreatic cancer cell line which expresses HER2. H2Mab-19 showed high binding affinity (KD: 1.2 × 10-8 M) against MIA PaCa-2 cells. Furthermore, H2Mab-19 significantly reduced tumor development in a MIA PaCa-2 xenograft model. These results suggest that treatment with H2Mab-19 may be a useful therapy for patients with HER2-expressing pancreatic cancers.

  25. Thr80 of Sheep Podoplanin Is a Critical Epitope of the Antisheep Podoplanin Monoclonal Antibody: PMab-256. 国際誌 査読有り

    Yukinari Kato, Masato Sano, Teizo Asano, Yusuke Sayama, Mika K Kaneko

    Monoclonal antibodies in immunodiagnosis and immunotherapy　2020年5月18日

    DOI： 10.1089/mab.2020.0010 　

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    An antisheep podoplanin (sPDPN) monoclonal antibody (mAb), PMab-256, has recently been established. PMab-256 shows positive immunostaining for lymphatic endothelial cells, lung type I alveolar cells, and kidney podocytes. PDPN possesses three platelet-aggregation-stimulating (PLAG) domains, PLAG1, PLAG2, and PLAG3, and a PLAG-like domain (PLD). The binding epitope of many anti-PDPN mAbs is located in PLAG domains or PLD. The purpose of this study is to determine the binding epitope of PMab-256. Analysis of sPDPN deletion mutants revealed that the N-terminus of the PMab-256 epitope exists between amino acids 75 and 80 of sPDPN. Furthermore, analysis of sPDPN point mutations demonstrated that the critical epitope includes Thr80 of sPDPN, indicating that the PMab-256 epitope is in the PLD of sPDPN.

  26. Epitope Mapping of PMab-241, a Lymphatic Endothelial Cell-Specific Anti-Bear Podoplanin Monoclonal Antibody. 国際誌 査読有り

    Yusuke Sayama, Masato Sano, Teizo Asano, Yoshikazu Furusawa, Junko Takei, Takuro Nakamura, Miyuki Yanaka, Saki Okamoto, Saori Handa, Yu Komatsu, Yoshimi Nakamura, Mikiko Yanagawa, Mika K Kaneko, Yukinari Kato

    Monoclonal antibodies in immunodiagnosis and immunotherapy　2020年4月2日

    DOI： 10.1089/mab.2020.0004 　

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    Anti-bear podoplanin (bPDPN) monoclonal antibodies (mAbs), including PMab-247 and PMab-241, have been previously established. Although PMab-247 has shown positive immunostaining for lymphatic endothelial cells (LECs), type I alveolar cells of the lung, and podocytes of the kidney, PMab-241 stains LECs but does not react with lung type I alveolar cells. PDPN possesses three platelet aggregation-stimulating (PLAG) domains (PLAG1, PLAG2, and PLAG3) and the PLAG-like domain (PLD). The binding epitope of PMab-247 was previously determined to include bPDPN residues Asp76, Arg78, Glu80, and Arg82. Among these, Glu80 and Arg82 are included in PLD of bPDPN. The purpose of this study is to determine the binding epitope of PMab-241 and to clarify the difference between these two anti-bPDPN mAbs. Analysis of bPDPN deletion mutants revealed that the N-terminus of the PMab-241 epitope exists between amino acids (aa) 75 and 80 of bPDPN. In addition, analysis of bPDPN point mutants demonstrated that the critical epitope of PMab-241 includes Thr75, Asp76, and Arg78 of bPDPN. The binding epitopes of PMab-241 and PMab-247 seem to overlap, but this slight difference may be sufficient to provide the specificity of PMab-241 to discriminate LECs from type I alveolar cells of the lung.

  27. Antibody-Drug Conjugates Using Mouse-Canine Chimeric Anti-Dog Podoplanin Antibody Exerts Antitumor Activity in a Mouse Xenograft Model. 国際誌 査読有り

    Yukinari Kato, Yuji Ito, Tomokazu Ohishi, Manabu Kawada, Takuro Nakamura, Yusuke Sayama, Masato Sano, Teizo Asano, Miyuki Yanaka, Saki Okamoto, Saori Handa, Yu Komatsu, Junko Takei, Mika K Kaneko

    Monoclonal antibodies in immunodiagnosis and immunotherapy　39　(2)　37-44　2020年4月

    DOI： 10.1089/mab.2020.0001 　

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    Antibody-drug conjugates (ADCs), which consist of a monoclonal antibody (mAb), a linker, and a payload, can deliver a drug to cancer tissues. We previously produced an anti-dog podoplanin (dPDPN) mAb, PMab-38, which reacts with dPDPN-expressing canine melanomas and squamous cell carcinomas (SCCs), but not with dPDPN-expressing canine type I alveolar cells or lymphatic endothelial cells, indicating that PMab-38 possesses cancer specificity. In this study, we developed an ADC, P38B-DM1, using the mouse-canine chimeric anti-dPDPN antibody, P38B as the antibody, a peptide linker, and emtansine as the payload using the chemical conjugation by affinity peptide (CCAP) method. We investigated its cytotoxicity against dPDPN-overexpressed Chinese hamster ovary (CHO/dPDPN) cells in vitro and its antitumor activity using a mouse xenograft model of CHO/dPDPN cells. P38B-DM1 showed cytotoxicity to CHO/dPDPN cells in a dose-dependent manner in vitro. Furthermore, P38B-DM1 exhibited higher antitumor activity than P38B in the mouse xenograft model. These results suggest that P38B-DM1, developed using the CCAP method, is useful for antibody therapy against dPDPN-expressing canine SCCs and melanomas.

  28. Development of Novel Mouse Monoclonal Antibodies Against Human CD19. 国際誌 査読有り

    Shinji Yamada, Mika K Kaneko, Yusuke Sayama, Teizo Asano, Masato Sano, Miyuki Yanaka, Takuro Nakamura, Saki Okamoto, Saori Handa, Yu Komatsu, Yoshimi Nakamura, Yoshikazu Furusawa, Junko Takei, Yukinari Kato

    Monoclonal antibodies in immunodiagnosis and immunotherapy　39　(2)　45-50　2020年4月

    DOI： 10.1089/mab.2020.0003 　

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    CD19 is a type I transmembrane glycoprotein belonging to the immunoglobulin superfamily. It is expressed in normal and neoplastic B cells, and it modulates the threshold of B cell activation for amplifying B cell receptor signaling. Blinatumomab (a CD3-CD19-bispecific T cell-engaging antibody) and tisagenlecleucel (genetically modified T cells that express a CD19 chimeric antigen receptor [CART-19]) provide significant benefits for patients with CD19-positive relapsed or refractory B cell malignancies. In this study, we first employed the Cell-Based Immunization and Screening (CBIS) method to produce anti-CD19 monoclonal antibodies using CD19-overexpressing cells for both immunization and screening. One established clone-C19Mab-1-proved to be useful in flow cytometry assays against lymphoma cell lines, such as BALL-1, P30/OHK, and Raji. Second, the extracellular domain of CD19 was immunized into mice, and enzyme-linked immunosorbent assays were performed for the first screening. One established clone-C19Mab-3-was determined to be useful for Western blotting and immunohistochemical analysis. Due to their complementary utility, a combination of C19Mab-1 (established using CBIS) and C19Mab-3 (established using conventional method) could be useful for the pathological analysis of CD19.

  29. Epitope Analysis of an Anti-Whale Podoplanin Monoclonal Antibody, PMab-237, Using Flow Cytometry. 国際誌 査読有り

    Yusuke Sayama, Masato Sano, Mika K Kaneko, Yukinari Kato

    Monoclonal antibodies in immunodiagnosis and immunotherapy　39　(1)　17-22　2020年2月

    DOI： 10.1089/mab.2019.0045 　

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    Podoplanin (PDPN) is a small mucin-type transmembrane glycoprotein, which was first discovered in podocytes of the kidney. PDPN is a specific lymphatic endothelial marker and is also known as T1alpha, a marker of lung type I alveolar cells, or Aggrus, a platelet aggregation-inducing factor. PDPN possesses three platelet aggregation-stimulating (PLAG) domains and PLAG-like domains (PLDs), which bind to C-type lectin-like receptor-2. Previously, we developed a novel anti-whale PDPN (wPDPN) monoclonal antibody (mAb) PMab-237 using the Cell-Based Immunization and Screening (CBIS) method and the RIEDL tag of Arg-Ile-Glu-Asp-Leu sequence. PMab-237 detected wPDPN by flow cytometry, western blot, and immunohistochemical analyses. However, the specific binding epitope of PMab-237 for wPDPN remains unknown. In this study, deletion mutants and point mutants of wPDPN with N-terminal RIEDL tag were produced to analyze the PMab-237 epitope using flow cytometry. The analysis of deletion mutants showed that the N-terminus of the PMab-237 epitope exists between the 80th amino acid (AA) and the 85th AA of wPDPN. In addition, the analysis of point mutants demonstrated that the critical epitope of PMab-237 includes Leu82 and Thr84 of wPDPN, indicating that the PMab-237 epitope is located in the PLD of wPDPN.

  30. The Epitope of PMab-210 Is Located in Platelet Aggregation-Stimulating Domain-3 of Pig Podoplanin. 国際誌 査読有り

    Mika K Kaneko, Yusuke Sayama, Masato Sano, Yukinari Kato

    Monoclonal antibodies in immunodiagnosis and immunotherapy　38　(6)　271-276　2019年12月

    DOI： 10.1089/mab.2019.0037 　

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    Podoplanin (PDPN)/T1alpha/Aggrus, a small mucin-type transmembrane glycoprotein, has been shown to be expressed on lymphatic endothelial cells and epithelial cells of many organs. PDPN is also upregulated in many cancers, and is involved in cancer metastasis and malignant progression. Human PDPN possesses three platelet aggregation-stimulating (PLAG) domains and the PLAG-like domain, which bind to C-type lectin-like receptor-2 (CLEC-2). Previously, we reported a novel antipig PDPN (pPDPN) monoclonal antibody (PMab-210) using Cell-Based Immunization and Screening (CBIS) method. PMab-210 specifically detected pPDPN-overexpressed Chinese hamster ovary (CHO)-K1 cells by flow cytometry and Western blot analysis. Immunohistochemical analyses demonstrated that PMab-210 stained pulmonary type I alveolar cells strongly and renal corpuscles weakly in pig or microminipig. However, the specific binding epitope of PMab-210 for pPDPN could not be determined by enzyme-linked immunosorbent assay using a series of pPDPN peptides. In this study, deletion mutants or point mutants of pPDPN were produced for analyzing the PMab-210 epitope using flow cytometry. The analysis of deletion mutants showed that N-terminus of PMab-210 epitope exists between 45th amino acid (aa) and 50th aa of pPDPN. In addition, the analysis of point mutants demonstrated that the critical epitope of PMab-210 could include Glu47, Asp48, Tyr49, Thr50, and Val51 of pPDPN, indicating that PMab-210 epitope is located in PLAG3 domain of pPDPN.

  31. Characterization of Anti-Goat Podoplanin Monoclonal Antibody PMab-235 Using Immunohistochemistry Against Goat Tissues. 国際誌 査読有り

    Takei J, Itai S, Harada H, Furusawa Y, Miwa T, Fukui M, Nakamura T, Sano M, Sayama Y, Yanaka M, Handa S, Hisamatsu K, Nakamura Y, Yamada S, Kaneko MK, Kato Y

    Monoclonal antibodies in immunodiagnosis and immunotherapy　38　(5)　213-219　2019年10月

    DOI： 10.1089/mab.2019.0022 　

  32. Epitope Mapping of Anti-Bear Podoplanin Monoclonal Antibody PMab-247. 国際誌 査読有り

    Kato Y, Takei J, Furusawa Y, Sayama Y, Sano M, Konnai S, Kobayashi A, Harada H, Takahashi M, Suzuki H, Yamada S, Kaneko MK

    Monoclonal antibodies in immunodiagnosis and immunotherapy　38　(5)　230-233　2019年10月

    DOI： 10.1089/mab.2019.0025 　

  33. Epitope Mapping of PMab-225 an Anti-Alpaca Podoplanin Monoclonal Antibody Using Flow Cytometry. 国際誌 査読有り

    Sayama Y, Sano M, Furusawa Y, Kaneko MK, Kato Y

    Monoclonal antibodies in immunodiagnosis and immunotherapy　38　(6)　255-260　2019年10月

    DOI： 10.1089/mab.2019.0033 　

  34. Epitope Analysis of an Antihorse Podoplanin Monoclonal Antibody PMab-219. 国際誌 査読有り

    Kato Y, Sayama Y, Sano M, Kaneko MK

    Monoclonal antibodies in immunodiagnosis and immunotherapy　38　(6)　266-270　2019年10月

    DOI： 10.1089/mab.2019.0034 　

  35. PMab-247 Detects Bear Podoplanin in Immunohistochemical Analysis. 国際誌 査読有り

    Takei J, Furusawa Y, Yamada S, Nakamura T, Sayama Y, Sano M, Konnai S, Kobayashi A, Harada H, Kaneko MK, Kato Y

    Monoclonal antibodies in immunodiagnosis and immunotherapy　38　(4)　171-174　2019年8月

    DOI： 10.1089/mab.2019.0019 　

  36. DzMab-1: Anti-Human Diacylglycerol Kinaseζ Monoclonal Antibody for Immunocytochemistry. 国際誌 査読有り

    Nakano T, Ogasawara S, Tanaka T, Hozumi Y, Sano M, Sayama Y, Yamada S, Kaneko MK, Kato Y, Goto K

    Monoclonal antibodies in immunodiagnosis and immunotherapy　38　(4)　179-182　2019年8月

    DOI： 10.1089/mab.2019.0024 　

  37. PMab-235: A monoclonal antibody for immunohistochemical analysis against goat podoplanin. 国際誌 査読有り

    Furusawa Y, Yamada S, Nakamura T, Sano M, Sayama Y, Itai S, Takei J, Harada H, Fukui M, Kaneko MK, Kato Y

    Heliyon　5　(7)　e02063　2019年7月

    DOI： 10.1016/j.heliyon.2019.e02063 　

  38. Chagas disease: A report of 17 suspected cases in Japan, 2012-2017 査読有り

    Imai, K., Misawa, K., Osa, M., Tarumoto, N., Sakai, J., Mikita, K., Sayama, Y., Fujikura, Y., Kawana, A., Murakami, T., Maesaki, S., Miura, S., Maeda, T.

    Tropical Medicine and Health　47　(1)　38　2019年

    DOI： 10.1186/s41182-019-0168-3 　

    ISSN：1349-4147 1348-8945

  39. Novel DNA virus isolated from samples showing endothelial cell necrosis in the Japanese eel, Anguilla japonica (vol 412, pg 179, 2011) 査読有り

    Tetsuya Mizutani, Yusuke Sayama, Akira Nakanishi, Hideharu Ochiai, Kouji Sakai, Kouji Wakabayashi, Nozomi Tanaka, Emi Miura, Mami Oba, Ichiro Kurane, Masayuki Saijo, Shigeru Morikawa, Shin-ichi Ono

    VIROLOGY　499　399-400　2016年12月

    DOI： 10.1016/j.virol.2016.10.019 　

    ISSN：0042-6822

  40. Development of a method to detect viral RNA sequences from cultured cells by combining size fraction and a rapid determination system for viral RNA sequences (RDV) 査読有り

    Watanabe, S., Mizutani, T., Sakai, K., Iizuka, I., Shiota, T., Sayama, Y., Tsuda, S., Kato, K., Fukushi, S., Saijo, M., Kurane, I., Morikawa, S., Akashi, H.

    Journal of Veterinary Science and Technology　1　(1)　103　2012年

    DOI： 10.4172/2157-7579.1000103 　

    ISSN：2157-7579

  41. Novel DNA virus isolated from samples showing endothelial cell necrosis in the Japanese eel, Anguilla japonica 査読有り

    Tetsuya Mizutani, Yusuke Sayama, Akira Nakanishi, Hideharu Ochiai, Kouji Sakai, Kouji Wakabayashi, Nozomi Tanaka, Emi Miura, Mami Oba, Ichiro Kurane, Masayuki Saijo, Shigeru Morikawa, Shin-ichi Ono

    VIROLOGY　412　(1)　179-187　2011年3月

    DOI： 10.1016/j.virol.2010.12.057 　

    ISSN：0042-6822

  42. West Nile virus: Understanding its past, present, and future

    Sayama, Y., Mizutani, T.

    Journal of Disaster Research　6　(4)　2011年

    DOI： 10.20965/jdr.2011.p0413 　

    ISSN：1883-8030 1881-2473

  43. Prevalence of Phasi Charoen Virus in Female Mosquitoes

    Yusuke Sayama, Yuki Eshita, Takuya Yamao, Miho Nishimura, Tomomitsu Satho, Raweewan Srisawat, Narumon Komalamisra, Yupha Rongsriyam, Kouji Sakai, Shuetsu Fukushi, Masayuki Saijo, Hitoshi Oshitani, Ichiro Kurane, Shigeru Morikawa, Tetsuya Mizutani

    J. Parasitology and Vector Biology　3　(1)　19-21　2011年1月

︎全件表示 ︎最初の5件までを表示

MISC 30

  1. 新規抗TROP2抗体を用いた乳がんに対する抗腫瘍効果の検討

    佐山 勇輔, 武井 潤子, 大石 智一, 金子 美華, 川田 学, 加藤 幸成

    日本癌学会総会記事　79回　OJ15-3　2020年10月

    出版者・発行元： (一社)日本癌学会

    ISSN： 0546-0476

  2. HER2を標的とした抗体医薬開発

    武井 潤子, 金子 美華, 大石 智一, 佐山 勇輔, 川田 学, 原田 浩之, 加藤 幸成

    日本癌学会総会記事　79回　OJ16-7　2020年10月

    出版者・発行元： (一社)日本癌学会

    ISSN： 0546-0476

  3. DGKzetaに対する新規抗体作製とそのエピトープ解析

    佐野 雅人, 淺野 禎三, 佐山 勇輔, 武井 潤子, 細野 秀樹, 金子 美華, 加藤 幸成

    日本生化学会大会プログラム・講演要旨集　93回　[2Z11-435)]　2020年9月

    出版者・発行元： (公社)日本生化学会

  4. 新規ペプチドタグシステムであるRIEDLタグはタンパク質精製に有用である(RIEDL tag, a novel peptide tag system is useful for protein purification)

    淺野 禎三, 佐山 勇輔, 佐野 雅人, 武井 潤子, 細野 秀樹, 金子 美華, 加藤 幸成

    日本生化学会大会プログラム・講演要旨集　93回　[3Z12-702)]　2020年9月

    出版者・発行元： (公社)日本生化学会

  5. CBIS法を用いた抗ウマポドプラニンモノクローナル抗体の樹立

    佐山 勇輔, 金子 美華, 加藤 幸成

    日本薬理学会年会要旨集　93　3-O-127　2020年

    出版者・発行元： 公益社団法人 日本薬理学会

    DOI： 10.1254/jpssuppl.93.0_3-o-127 　

    eISSN： 2435-4953

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    Purpose: Podoplanin is expressed in normal tissues including renal podocytes and lymphatic endothelial cells. To investigate the expression and function of horse podoplanin (horPDPN), sensitive and specific mAbs against horPDPN are necessary. In this study, we aimed to develop useful anti-horPDPN mAbs for many applications such as flow cytometry (FCM), western blot (WB), and immunohistochemistry (IHC). Methods: We employed a conventional immunization method using synthetic peptides or Cell-Based Immunization and Screening (CBIS) method using horPDPN-expressed mammalian cells for producing anti-horPDPN mAbs. Anti-horPDPN mAbs were screened using enzyme-linked immunosorbent assay or FCM. Established anti-horPDPN mAbs were characterized using FCM, WB, and IHC. Results: We developed two anti-horPDPN mAbs, PMab-202 using the peptide immunization and PMab-219 using CBIS method. PMab-202 reacted with horPDPN in FCM and WB, but did not stain horPDPN in IHC. In contrast, PMab-219 detected horPDPN in not only FCM and WB, but also IHC. Conclusion: We have successfully established mouse anti-horPDPN mAbs, PMab-202 and PMab-219. PMab-219 is applicable for FCM, WB, and IHC analyses. CBIS method could be more advantageous to establish immunohistochemistry-applicable mAbs for elucidating the pathophysiological function of horPDPN.

  6. Benznidazoleにて加療し5年間寛解維持し得た慢性Chagas病の1例

    池野 義彦, 三浦 左千夫, 前田 卓哉, 今井 一男, 佐山 勇輔, 景山 倫也, 大口 真寿, 薄井 啓一郎, 高野 尊行, 倉沢 和宏, 阿久津 郁夫

    Clinical Parasitology　30　(1)　62-64　2019年12月

    出版者・発行元： 日本臨床寄生虫学会

    ISSN： 1341-5190

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    症例は流行地域より来日し約25年在留している成人で、献血Chagas病疫学調査でTrypanosoma cruzi抗体陽性を指摘され、当院を受診した。全血T.cruzi PCR、培養陽性、II度房室ブロックおよびModified Kuschnir ClassificationでI相当の心左室壁運動の全周性な低下を確認した。慢性Chagas心筋症と診断し、Benznidazole 400mg 60日間投与を行った。治療により全血T.cruzi PCRおよび培養陰転化した。その後もT.cruzi抗体、PCR、培養検査、心病変進行、腸管病変出現を指標とし経過観察を進めているが、T.cruzi PCR、培養陽転化、臓器病変の進行を認めず5年以上寛解が維持できていることを確認した。

  7. Benznidazoleにて加療し5年間寛解維持し得た慢性Chagas病の1例

    池野 義彦, 三浦 左千夫, 前田 卓哉, 今井 一男, 佐山 勇輔, 景山 倫也, 大口 真寿, 薄井 啓一郎, 高野 尊行, 倉沢 和宏, 阿久津 郁夫

    日本臨床寄生虫学会大会プログラム・講演要旨　30回　32-32　2019年5月

    出版者・発行元： 日本臨床寄生虫学会

  8. CBIS法を用いた抗ブタポドプラニン抗体の樹立

    古澤慶一, 古澤慶一, 古澤慶一, 山田慎二, 金子美華, 武井潤子, 佐野雅人, 佐山勇輔, 三輪崇志, 福井真人, 加藤幸成, 加藤幸成

    日本生化学会大会(Web)　92nd　[2T14m-03]　2019年

    出版者・発行元： (公社)日本生化学会

  9. Cell-Based Immunization and Screening(CBIS)法を用いた抗ヤギポドプラニンモノクローナル抗体の樹立

    佐山勇輔, 山田慎二, 佐野雅人, 古澤慶一, 古澤慶一, 古澤慶一, 三輪崇志, 福井真人, 金子美華, 加藤幸成, 加藤幸成

    日本生化学会大会(Web)　92nd　[2T14a-05]　2019年

    出版者・発行元： (公社)日本生化学会

  10. シャーガス病検査依頼症例と確定診断症例に関する検討

    今井 一男, 長 盛親, 池野 義彦, 酒井 純, 樽本 憲人, 前田 卓哉, 川名 明彦, 前崎 繁文, 三浦 左千夫, 佐山 勇輔

    感染症学雑誌　92　(3)　484-484　2018年5月

    出版者・発行元： (一社)日本感染症学会

    ISSN： 0387-5911

    eISSN： 1884-569X

  11. 西日本における中南米滞在歴のある献血者血液のT.cruzi抗体検査の実施状況

    野口 洋介, 楠村 静, 堂上 真由, 坂本 賢一, 辻 美佐子, 佐山 勇輔, 松本 千惠子, 木村 恵子, 堀 勇二, 百瀬 俊也, 松林 圭二, 藤村 吉博

    日本輸血細胞治療学会誌　64　(2)　434-434　2018年4月

    出版者・発行元： (一社)日本輸血・細胞治療学会

    ISSN： 1881-3011

    eISSN： 1883-0625

  12. シリアンハムスターにおけるヒトバベシア症原因原虫Babesia microti(Kobe-typeおよびUS-type)の感染動態

    佐山 勇輔, 新倉 綾, 松本 千惠子, 西條 政幸, 松林 圭二, 永井 正, 佐竹 正博

    日本輸血細胞治療学会誌　64　(2)　355-355　2018年4月

    出版者・発行元： (一社)日本輸血・細胞治療学会

    ISSN： 1881-3011

    eISSN： 1883-0625

  13. シャーガス病における抗体確認検査試薬の評価

    佐山 勇輔, 高倉 明子, 松本 千惠子, 古居 保美, 平 力造, 立山 英美, 石丸 健, 松林 圭二, 永井 正, 佐竹 正博

    血液事業　40　(2)　393-393　2017年8月

    出版者・発行元： 日本血液事業学会

    ISSN： 0917-7833

  14. 西日本における献血血液のT.cruzi抗体検査の実施状況とその背景

    楠村 静, 野口 洋介, 堂上 真由, 坂本 賢一, 辻 美佐子, 佐山 勇輔, 木村 恵子, 堀 勇二, 百瀬 俊也, 松林 圭二, 藤村 吉博

    血液事業　40　(2)　394-394　2017年8月

    出版者・発行元： 日本血液事業学会

    ISSN： 0917-7833

  15. 生物由来製品に関する感染症定期報告制度と報告状況について

    古居 保美, 池田 紗織, 高田 雅彦, 鈴木 光, 佐山 勇輔, 廣井 和雄, 森山 哲, 平 力造

    血液事業　40　(2)　472-472　2017年8月

    出版者・発行元： 日本血液事業学会

    ISSN： 0917-7833

  16. ヒトバベシア症原因原虫Babesia microti遺伝子型間における抗体反応性の解析

    佐山 勇輔, 新倉 綾, 松本 千惠子, 西條 政幸, 松林 圭二, 永井 正, 佐竹 正博

    日本輸血細胞治療学会誌　63　(3)　409-409　2017年6月

    出版者・発行元： (一社)日本輸血・細胞治療学会

    ISSN： 1881-3011

    eISSN： 1883-0625

  17. ヒトバベシア症における解析方法の構築

    佐山 勇輔, 新倉 綾, 松本 千惠子, 松林 圭二, 永井 正, 佐竹 正博

    血液事業　39　(2)　382-382　2016年8月

    出版者・発行元： 日本血液事業学会

    ISSN： 0917-7833

  18. 輸血用血液製剤中のTrypanosoma cruzi(シャーガス病原虫)の動態 白血球除去フィルターおよび赤血球製剤を中心に

    佐山 勇輔, 松本 千惠子, 山岸 尚仁, 内田 茂治, 永井 正, 佐竹 正博

    日本輸血細胞治療学会誌　62　(2)　296-296　2016年4月

    出版者・発行元： (一社)日本輸血・細胞治療学会

    ISSN： 1881-3011

    eISSN： 1883-0625

  19. Toxoplasma gondii-derived heat shock protein 70 induces lethal anaphylactic reaction through activation of cytosolic phospholipase A(2) and platelet-activating factor via Toll-like receptor 4/myeloid differentiation factor 88 (vol 52, pg 366, 2008)

    H. Fang, H. -S Mun, A. Kikumura, Y. Sayama, K. Norose, A. Yano, F. Aosai

    MICROBIOLOGY AND IMMUNOLOGY　60　(3)　209-209　2016年3月

    DOI： 10.1111/1348-0421.12358 　

    ISSN： 0385-5600

    eISSN： 1348-0421

  20. Benznidazoleで加療し得たChagas病患者の1例

    池野 義彦, 三浦 左千夫, 佐山 勇輔, 福島 史哉, 崎尾 浩由, 田宮 千知, 亀井 亮平, 矢野 秀樹, 大口 真寿, 薄井 啓一郎, 川合 覚, 桐木 雅史, 奥住 捷子, 吉田 敦, 千種 雄一, 阿久津 郁夫

    Clinical Parasitology　26　(1)　90-92　2015年12月

    出版者・発行元： 日本臨床寄生虫学会

    ISSN： 1341-5190

    詳細を見る 詳細を閉じる

    症例は男性で、流行地域より来日し、約25年間在留していた。献血者Chagas病疫学検査でT.cruzi抗体陽性で、精査を希望して受診した。家族歴では、姉がChagas病と診断され、経過観察されている。意識鮮明、眼球結膜・眼瞼結膜有意所見なし、頸部リンパ節触知せず、胸部聴診で心音不整あり、心雑音なし、四肢麻痺・浮腫なし、皮膚症状は認めなかった。心電図で房室ブロックを認めた。その後のT.cruzi培養で陽性を確認した。50歳以下であり、慢性期再燃性の原虫症の存在を証明した。治療適応と判断し、ベンズニダゾールで治療を開始した。皮膚症状、末梢神経症状などの有害事象を認めず、60日間の治療を完遂した。T.cruzi PCR及び培養陰転化を認め、治療効果ありと判断した。外来で経過観察を予定している。

  21. マラリア関連検査法における高感度検出法の検討

    高倉 明子, 佐山 勇輔, 宮川 恵子, 小堺 萌, 日高 孝夫, 松本 千恵子, 内田 茂治, 永井 正, 佐竹 正博, 田所 憲治

    血液事業　38　(2)　482-482　2015年8月

    出版者・発行元： 日本血液事業学会

    ISSN： 0917-7833

  22. PXBマウスを用いたHBs抗体によるHBV感染阻止試験

    星 友二, 若林 菜穂子, 佐山 勇輔, 山岸 尚仁, 長谷川 隆, 五反田 裕子, 内田 茂治, 佐竹 正博, 田所 憲治

    日本輸血細胞治療学会誌　61　(2)　302-302　2015年4月

    出版者・発行元： (一社)日本輸血・細胞治療学会

    ISSN： 1881-3011

    eISSN： 1883-0625

  23. ベンズニダゾールにより治療を行ったシャーガス病の2症例

    前田 卓哉, 南雲 盛親, 佐山 勇輔, 三沢 和央, 今井 一男, 藤倉 雄二, 河野 修一, 原 悠, 叶 宗一郎, 三木田 馨, 小野 岳史, 宮平 靖, 川名 明彦, 三浦 左千夫

    Clinical Parasitology　24　(1)　33-36　2013年12月

    出版者・発行元： 日本臨床寄生虫学会

    ISSN： 1341-5190

    詳細を見る 詳細を閉じる

    ベンズニダゾールにより治療を行ったシャーガス病の2例を経験した。症例1は14歳男で、推定感染ルートは母児感染の先天性シャーガス病である。ベンズニダゾールを経口投与した。9日後には、両側の前腕ならびに手掌にそう痒を伴う小紅斑が出現した。皮疹に対して無治療のままベンズニダゾールの投与を継続したが、3日後に皮疹は自然に消退した。皮疹の他には有害事象はみられず、薬剤の内服を完了した。症例2は55歳女で、推定感染ルートはブラジルでのサシガメによる虫刺で、心臓病合併を有する慢性シャーガス病である。ベンズニダゾールを経口投与した。軽度肝障害が出現したが継続した。両下肢の末端から表在感覚の異常が出現し、ベンズニダゾールによる末梢神経症と診断した。ベンズニダゾールを中止し、メコバラミンおよびカルバマゼピンを投与した。第116日には上肢症状は消失した。

  24. ベンズニダゾールにより治療を行ったシャーガス病の2症例

    前田 卓哉, 南雲 盛親, 佐山 勇輔, 三沢 和央, 藤倉 雄二, 河野 修一, 原 悠, 叶 宗一郎, 三木田 馨, 小野 岳史, 宮平 靖, 川名 明彦, 三浦 左千夫

    日本臨床寄生虫学会大会プログラム・講演要旨　24回　17-17　2013年6月

    出版者・発行元： 日本臨床寄生虫学会

  25. レストンエボラウイルス自然感染カニクイザルにおける免疫応答の解析

    谷口怜, 佐山勇輔, 永田典代, 飯塚愛恵, 谷英樹, 吉河智城, 福士秀悦, 西條政幸, 久和茂, 森川茂

    日本ウイルス学会学術集会プログラム・抄録集　60th　426　2012年10月31日

  26. テロの可能性のある病原体等の早期検知・迅速診断法の開発とその評価法の確立に関わる研究 ウイルス性特定病原体の鑑別診断法の開発

    森川茂, 佐山勇輔, 谷口怜, 福士秀悦, 水谷哲也, 西條政幸, 倉根一郎

    テロの可能性のある病原体等の早期検知・迅速診断法の開発とその評価法の確立に関わる研究 平成22年度 総括・分担研究報告書　17-20　2011年

  27. 現在,国内で分離・同定できないウイルス性出血熱等の診断等の対応方法に関する研究 新種アレナウイルス性出血熱の診断法,モルビリウイルス,ポックスウイルスの宿主域拡大の解析と総括

    森川茂, 伊波興一朗, 谷口怜, 佐山勇輔, 福士秀悦, 水谷哲也, 緒方もも子, 西條政幸, 酒井宏治, 網康至, 新倉綾, 永田典代, 岩田奈織子, 倉根一郎, 池郁生, 前田健, 有川二郎, 鎌倉和政, 滝本浩司, 山崎勝彦, 飯塚信二, 内田幸憲, ROMANOWSKI Victor, ENRIA Delia A

    現在、国内で分離・同定できないウイルス性出血熱等の診断等の対応方法に関する研究 平成22年度 総括・分担研究報告書　8-16　2011年

  28. レストンエボラウイルス膜糖蛋白を標的とした抗体検出系の確立

    谷口 怜, 佐山 勇輔, 渡辺 俊平, 飯塚 愛恵, 福士 秀悦, 水谷 哲也, 石井 寿幸, 久和 茂, 明石 博臣, 吉川 泰弘, 森川 茂, 倉根 一郎

    日本獣医学会学術集会講演要旨集　150回　231-231　2010年9月

    出版者・発行元： (公社)日本獣医学会

    ISSN： 1347-8621

  29. テロの可能性のある病原体等の早期検知・迅速診断法の開発とその評価法の確立に関わる研究 2.ウイルス性特定病原体の鑑別診断法の開発

    森川茂, 谷口怜, 佐山勇輔, 福士秀悦, 水谷哲也, 西條政幸, 倉根一郎

    テロの可能性のある病原体等の早期検知・迅速診断法の開発とその評価法の確立に関わる研究 平成21年度 総括・分担研究報告書　21-25　2010年

  30. エミューと他鳥種間の卵白成分の電気泳動像の比較

    横濱 道成, 佐山 勇輔, 小川 博

    生物物理化学　53　(2)　41-42　2009年

    出版者・発行元： 日本電気泳動学会

    DOI： 10.2198/sbk.53.41 　 10.3136/fstr.16.149_references_DOI_RhpgsbJ6sh99O9iVZJrhA3Astzq 　

    ISSN： 0031-9082

    eISSN： 1349-9785

︎全件表示 ︎最初の5件までを表示

講演・口頭発表等 8

  1. 5歳未満の小児重症肺炎死亡例における呼吸器病原体のメタゲノム解析

    佐山 勇輔, 今村 剛朗, 岡本 道子, 斉藤 繭子, 押谷 仁

    日本臨床ウイルス学会　2025年

  2. Epidemiology and Clinical Characteristics of Human Parainfluenza Virus Types 1–4 in Children Under 5 Years of Age in the Philippines

    中西 進斗, 佐山 勇輔, 斉藤 繭子, 岡本 道子, 齋藤, 小畑, 麻理子, 今村 剛朗, 玉記 雷太, Veronica L Tallo, Socorro P Lupisa, 押谷 仁

    日本臨床ウイルス学会　2024年

  3. Seroprevalence of human coronaviruses in pediatric samples collected in the COVID-19 pre-pandemic period in the Philippines and Japan

    Yusuke Sayama, Michiko Okamoto, Mayuko Saito, Mariko Saito-Obata, Raita Tamaki, Christine Dahlia Joboco, Socorro Lupisan, Hitoshi Oshitani

    American Society of Tropical Medicine and Hygiene　2023年

  4. Genetic analysis of human parainfluenza virus type 1 in Biliran Island, Philippines, from 2012－2019

    Eiji Otomo, Yusuke Sayama, Michiko Okamoto, Mayuko Saito, Mariko Saito-Obata, Raita Tamaki, Socorro Lupisan, Beatriz P Quiambao, Hitoshi Oshitani

    日本ウイルス学会　2023年

  5. Seroprevalence of seasonal human coronaviruses and reactivity with SARS-CoV-2 in samples collected before the COVID-19 pandemic

    Chuan Lo, Yusuke Sayama, Hiroki Tomizawa, Mayuko Saito, Michiko Okamoto, Suguru Ohmiya, Yukio Nagai, Hidekazu Nishimura, Hitoshi Oshitani

    日本ウイルス学会　2023年

  6. Cell-Based Immunization and Screening(CBIS)法を用いた抗ヤギポドプラニンモノクローナル抗体の樹立

    佐山勇輔, 山田慎二, 佐野雅人, 古澤慶一, 三輪崇志, 福井真人, 金子美華, 加藤幸成, 加藤幸成

    日本生化学会大会　2019年

  7. シリアンハムスターにおけるヒトバベシア症原因原虫Babesia microti(Kobe-typeおよびUS-type)の感染動態

    佐山 勇輔, 新倉 綾, 松本 千惠子, 西條 政幸, 松林 圭二, 永井 正, 佐竹 正博

    日本輸血細胞治療学会　2018年

  8. シャーガス病における抗体確認検査試薬の評価

    佐山 勇輔, 高倉 明子, 松本 千惠子, 古居 保美, 平 力造, 立山 英美, 石丸 健, 松林 圭二, 永井 正, 佐竹 正博

    日本血液事業学会　2017年

︎全件表示 ︎最初の5件までを表示

共同研究・競争的資金等の研究課題 5

  1. 出生コホート研究を基盤とした乳幼児における呼吸器ウイルス感染症のリスク因子の解明

    佐山 勇輔

    2024年4月1日 ～ 2027年3月31日

  2. 新型コロナウイルス感染症の小児における感染伝播と疫学像に関与する要因の解析

    佐山 勇輔

    2022年8月 ～ 2025年3月

    詳細を見る 詳細を閉じる

    SARS-CoV-2による新型コロナウイルス感染症(COVID-19)では、子供は成人に比べて、感染しにくく、伝播しにくいことが知られている。本研究は、COVID-19流行前後に採取された小児及び成人検体を用い、成人に比べ小児がSARS-CoV-2と近縁な4種類の普通感冒ヒトコロナウイルス(HCoV)の感染により誘導された抗体がSARS-CoV-2に対しても交差反応性や中和能を有するかどうかを明らかにすることを目的としている。 本年度は、前年度までには実施できなかった成人群についても解析を行った。COVID-19流行以前に日本で採取された小児及び成人血清、計747検体を用いて、本研究で確立した各種血清学方法により解析をおこなった。その結果、抗体陽性率が90%に達したのは、HCoV-NL63、HCoV-HKU1、HCoV-OC43では3-4歳だった一方、HCoV-229Eでは、8歳であった。その後、ほぼ100%の抗体陽性率を維持していた。普通感冒ヒトコロナウイルスの中でも前年度に実施したフィリピンで採取された小児検体を用いた結果とは異なり、地域により抗体陽性率の推移が異なることが示された。また、SARS-CoV-2に対する血清学解析では、小児と成人の中で抗体陽性率に差を認めなかったが、小児群の特に5歳以下の群は、SARS-CoV-2に対する抗体価が成人群に比べて高かった。しかし、ELISAによりSARS-CoV-2にRatio 3<以上を示した小児・成人検体は、全てSARS-CoV-2に対し、中和能を示さなかった。前年度でもフィリピンでCOVID-19流行以前に採取された小児検体のうち、ELISAによりSARS-CoV-2に反応を示した検体でもほとんど中和能を示さなかった。今後は、異なるSARS-CoV-2の変異株であるオミクロン株などとの反応性などを含め、追加解析を実施する。

  3. 母乳成分の解析を通した乳児におけるウイルス感染と細菌叢への関与の解明

    佐山 勇輔

    2024年 ～ 2024年

  4. アジアにおけるインフルエンザウイルスの疫学解析ネットワークの構築

    鈴木 陽, 押谷 仁, 神垣 太郎, 齊藤 麻理子, 玉記 雷太, 古瀬 祐気, 藤 直子, 島袋 梢, 貫和 奈央, 佐山 祐輔, 今川 稔文, 五江渕 景明, 小田切 崇, 大野 歩, 岡田 貴志

    提供機関：Japan Society for the Promotion of Science

    制度名：Grants-in-Aid for Scientific Research

    研究種目：Grant-in-Aid for Scientific Research (B)

    研究機関：Tohoku University

    2009年 ～ 2011年

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    熱帯のフィリピンおよび亜寒帯のモンゴルおよび温帯の日本を結んだアジアにおけるインフルエンザ研究ネットワークを形成した。フィリピンでは2009年5月の新型インフルエンザ流行後、断続的にインフルエンザウイルスが検出されたが、モンゴルでは9月になり初めて患者が検出されたと同時に爆発的に流行した。気候、人の国内外への移動の頻度、インフルエンザと同様な呼吸器症状をきたす感染症の同時流行の有無により、インフルエンザサーベイランスの方法を調整する必要性がある事が明らかになった。

  5. 発展途上国における新興感染症に対する早期警戒システムの構築のための基礎研究

    押谷 仁, 鈴木 陽, 神垣 太郎, 小坂 健, 関根 雅夫, 古瀬 祐気, 藤 直子, 貫和 奈央, 佐山 勇輔, 今川 稔文, 二口 尚美

    提供機関：Japan Society for the Promotion of Science

    制度名：Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目：Grant-in-Aid for Scientific Research (B)

    研究機関：Tohoku University

    2007年 ～ 2009年

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    近年の新興感染症では短期間に世界中に国境を越えて広がるということが特徴としてあげられ、効果的な対応するためには、従来のサーベイランスを強化するとともに新たなシステムを開発する必要がある。本研究を通して、サーベイランスデータの解析ではその地域の人口学的な特徴を勘案する必要があること、難民の発生地域など脆弱な保健システムにおいてもサーベイランスによる探知が対策に必須であること、その中で実験室的な確定診断が重要であるが、核酸増幅や抗体検出などの新たな系の確立が重要であると考えられた。