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7. Characterization of SARS-CoV-2 Omicron BA.2.75 clinical isolates

Author

Uraki, Ryuta, Iida, Shun, Halfmann, Peter J., Yamayoshi, Seiya, Hirata, Yuichiro, Iwatsuki-Horimoto, Kiyoko, Kiso, Maki, Ito, Mutsumi, Furusawa, Yuri, Ueki, Hiroshi, Sakai-Tagawa, Yuko, Kuroda, Makoto, Maemura, Tadashi, Kim, Taksoo, Mine, Sohtaro, Iwamoto, Noriko, Li, Rong, Liu, Yanan, Larson, Deanna, Fukushi, Shuetsu, Watanabe, Shinji, Maeda, Ken, Wang, Zhongde, Ohmagari, Norio, Theiler, James, Fischer, Will, Korber, Bette, Imai, Masaki, Suzuki, Tadaki, and Kawaoka, Yoshihiro

Published
2023
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8. Identification of SARS-CoV-2 Mpro inhibitors containing P1’ 4-fluorobenzothiazole moiety highly active against SARS-CoV-2

Author

Higashi-Kuwata, Nobuyo, Tsuji, Kohei, Hayashi, Hironori, Bulut, Haydar, Kiso, Maki, Imai, Masaki, Ogata-Aoki, Hiromi, Ishii, Takahiro, Kobayakawa, Takuya, Nakano, Kenta, Takamune, Nobutoki, Kishimoto, Naoki, Hattori, Shin-ichiro, Das, Debananda, Uemura, Yukari, Shimizu, Yosuke, Aoki, Manabu, Hasegawa, Kazuya, Suzuki, Satoshi, Nishiyama, Akie, Saruwatari, Junji, Shimizu, Yukiko, Sukenaga, Yoshikazu, Takamatsu, Yuki, Tsuchiya, Kiyoto, Maeda, Kenji, Yoshimura, Kazuhisa, Iida, Shun, Ozono, Seiya, Suzuki, Tadaki, Okamura, Tadashi, Misumi, Shogo, Kawaoka, Yoshihiro, Tamamura, Hirokazu, and Mitsuya, Hiroaki

Published
2023
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13. Characterization of SARS-CoV-2 Omicron BA.4 and BA.5 isolates in rodents

Author

Uraki, Ryuta, Halfmann, Peter J., Iida, Shun, Yamayoshi, Seiya, Furusawa, Yuri, Kiso, Maki, Ito, Mutsumi, Iwatsuki-Horimoto, Kiyoko, Mine, Sohtaro, Kuroda, Makoto, Maemura, Tadashi, Sakai-Tagawa, Yuko, Ueki, Hiroshi, Li, Rong, Liu, Yanan, Larson, Deanna, Fukushi, Shuetsu, Watanabe, Shinji, Maeda, Ken, Pekosz, Andrew, Kandeil, Ahmed, Webby, Richard J., Wang, Zhongde, Imai, Masaki, Suzuki, Tadaki, and Kawaoka, Yoshihiro

Published
2022
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14. Potent neutralizing broad-spectrum antibody against SARS-CoV-2 generated from dual-antigen-specific B cells from convalescents

Author

Takeshita, Masaru, Fukuyama, Hidehiro, Kamada, Katsuhiko, Matsumoto, Takehisa, Makino-Okamura, Chieko, Lin, Qingshun, Sakuma, Machie, Kawahara, Eiki, Yamazaki, Isato, Uchikubo-Kamo, Tomomi, Tomabechi, Yuri, Hanada, Kazuharu, Hisano, Tamao, Moriyama, Saya, Takahashi, Yoshimasa, Ito, Mutsumi, Imai, Masaki, Maemura, Tadashi, Furusawa, Yuri, Yamayoshi, Seiya, Kawaoka, Yoshihiro, Shirouzu, Mikako, Ishii, Makoto, Saya, Hideyuki, Kondo, Yasushi, Kaneko, Yuko, Suzuki, Katsuya, Fukunaga, Koichi, and Takeuchi, Tsutomu

Published
2023
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17. Characterization and antiviral susceptibility of SARS-CoV-2 Omicron BA.2

Author

Uraki, Ryuta, Kiso, Maki, Iida, Shun, Imai, Masaki, Takashita, Emi, Kuroda, Makoto, Halfmann, Peter J., Loeber, Samantha, Maemura, Tadashi, Yamayoshi, Seiya, Fujisaki, Seiichiro, Wang, Zhongde, Ito, Mutsumi, Ujie, Michiko, Iwatsuki-Horimoto, Kiyoko, Furusawa, Yuri, Wright, Ryan, Chong, Zhenlu, Ozono, Seiya, Yasuhara, Atsuhiro, Ueki, Hiroshi, Sakai-Tagawa, Yuko, Li, Rong, Liu, Yanan, Larson, Deanna, Koga, Michiko, Tsutsumi, Takeya, Adachi, Eisuke, Saito, Makoto, Yamamoto, Shinya, Hagihara, Masao, Mitamura, Keiko, Sato, Tetsuro, Hojo, Masayuki, Hattori, Shin-ichiro, Maeda, Kenji, Valdez, Riccardo, Okuda, Moe, Murakami, Jurika, Duong, Calvin, Godbole, Sucheta, Douek, Daniel C., Maeda, Ken, Watanabe, Shinji, Gordon, Aubree, Ohmagari, Norio, Yotsuyanagi, Hiroshi, Diamond, Michael S., Hasegawa, Hideki, Mitsuya, Hiroaki, Suzuki, Tadaki, and Kawaoka, Yoshihiro

Published
2022
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18. Characterization of a new SARS-CoV-2 variant that emerged in Brazil

Author

Imai, Masaki, Halfmann, Peter J., Yamayoshi, Seiya, Iwatsuki-Horimoto, Kiyoko, Chiba, Shiho, Watanabe, Tokiko, Nakajima, Noriko, Ito, Mutsumi, Kuroda, Makoto, Kiso, Maki, Maemura, Tadashi, Takahashi, Kenta, Loeber, Samantha, Hatta, Masato, Koga, Michiko, Nagai, Hiroyuki, Yamamoto, Shinya, Saito, Makoto, Adachi, Eisuke, Akasaka, Osamu, Nakamura, Morio, Nakachi, Ichiro, Ogura, Takayuki, Baba, Rie, Fujita, Kensuke, Ochi, Junichi, Mitamura, Keiko, Kato, Hideaki, Nakajima, Hideaki, Yagi, Kazuma, Hattori, Shin-ichiro, Maeda, Kenji, Suzuki, Tetsuya, Miyazato, Yusuke, Valdez, Riccardo, Gherasim, Carmen, Furusawa, Yuri, Okuda, Moe, Ujie, Michiko, Lopes, Tiago J. S., Yasuhara, Atsuhiro, Ueki, Hiroshi, Sakai-Tagawa, Yuko, Eisfeld, Amie J., Baczenas, John J., Baker, David A., O’Connor, Shelby L., O’Connor, David H., Fukushi, Shuetsu, Fujimoto, Tsuguto, Kuroda, Yudai, Gordon, Aubree, Maeda, Ken, Ohmagari, Norio, Sugaya, Norio, Yotsuyanagi, Hiroshi, Mitsuya, Hiroaki, Suzuki, Tadaki, and Kawaoka, Yoshihiro

Published
2021

19. SARS-CoV-2 Omicron virus causes attenuated disease in mice and hamsters

Author

Halfmann, Peter J., Iida, Shun, Iwatsuki-Horimoto, Kiyoko, Maemura, Tadashi, Kiso, Maki, Scheaffer, Suzanne M., Darling, Tamarand L., Joshi, Astha, Loeber, Samantha, Singh, Gagandeep, Foster, Stephanie L., Ying, Baoling, Case, James Brett, Chong, Zhenlu, Whitener, Bradley, Moliva, Juan, Floyd, Katharine, Ujie, Michiko, Nakajima, Noriko, Ito, Mutsumi, Wright, Ryan, Uraki, Ryuta, Warang, Prajakta, Gagne, Matthew, Li, Rong, Sakai-Tagawa, Yuko, Liu, Yanan, Larson, Deanna, Osorio, Jorge E., Hernandez-Ortiz, Juan P., Henry, Amy R., Ciuoderis, Karl, Florek, Kelsey R., Patel, Mit, Odle, Abby, Wong, Lok-Yin Roy, Bateman, Allen C., Wang, Zhongde, Edara, Venkata-Viswanadh, Chong, Zhenlu, Franks, John, Jeevan, Trushar, Fabrizio, Thomas, DeBeauchamp, Jennifer, Kercher, Lisa, Seiler, Patrick, Gonzalez-Reiche, Ana Silvia, Sordillo, Emilia Mia, Chang, Lauren A., van Bakel, Harm, Simon, Viviana, Douek, Daniel C., Sullivan, Nancy J., Thackray, Larissa B., Ueki, Hiroshi, Yamayoshi, Seiya, Imai, Masaki, Perlman, Stanley, Webby, Richard J., Seder, Robert A., Suthar, Mehul S., García-Sastre, Adolfo, Schotsaert, Michael, Suzuki, Tadaki, Boon, Adrianus C. M., Diamond, Michael S., and Kawaoka, Yoshihiro

Published
2022
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21. Potent SARS-CoV-2 neutralizing antibodies with therapeutic effects in two animal models

Author

Takeshita, Masaru, Fukuyama, Hidehiro, Kamada, Katsuhiko, Matsumoto, Takehisa, Makino-Okamura, Chieko, Uchikubo-Kamo, Tomomi, Tomabechi, Yuri, Hanada, Kazuharu, Moriyama, Saya, Takahashi, Yoshimasa, Ishigaki, Hirohito, Nakayama, Misako, Nguyen, Cong Thanh, Kitagawa, Yoshinori, Itoh, Yasushi, Imai, Masaki, Maemura, Tadashi, Furusawa, Yuri, Ueki, Hiroshi, Iwatsuki-Horimoto, Kiyoko, Ito, Mutsumi, Yamayoshi, Seiya, Kawaoka, Yoshihiro, Shirouzu, Mikako, Ishii, Makoto, Saya, Hideyuki, Kondo, Yasushi, Kaneko, Yuko, Suzuki, Katsuya, Fukunaga, Koichi, and Takeuchi, Tsutomu

Published
2022
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23. Enhanced fusogenicity and pathogenicity of SARS-CoV-2 Delta P681R mutation

Author

Saito, Akatsuki, Irie, Takashi, Suzuki, Rigel, Maemura, Tadashi, Nasser, Hesham, Uriu, Keiya, Kosugi, Yusuke, Shirakawa, Kotaro, Sadamasu, Kenji, Kimura, Izumi, Ito, Jumpei, Wu, Jiaqi, Iwatsuki-Horimoto, Kiyoko, Ito, Mutsumi, Yamayoshi, Seiya, Loeber, Samantha, Tsuda, Masumi, Wang, Lei, Ozono, Seiya, Butlertanaka, Erika P., Tanaka, Yuri L., Shimizu, Ryo, Shimizu, Kenta, Yoshimatsu, Kumiko, Kawabata, Ryoko, Sakaguchi, Takemasa, Tokunaga, Kenzo, Yoshida, Isao, Asakura, Hiroyuki, Nagashima, Mami, Kazuma, Yasuhiro, Nomura, Ryosuke, Horisawa, Yoshihito, Yoshimura, Kazuhisa, Takaori-Kondo, Akifumi, Imai, Masaki, Tanaka, Shinya, Nakagawa, So, Ikeda, Terumasa, Fukuhara, Takasuke, Kawaoka, Yoshihiro, and Sato, Kei

Published
2022
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26. Syrian hamsters as a small animal model for SARS-CoV-2 infection and countermeasure development

Author

Imai, Masaki, Iwatsuki-Horimoto, Kiyoko, Hatta, Masato, Loeber, Samantha, Halfmann, Peter J., Nakajima, Noriko, Watanabe, Tokiko, Ujie, Michiko, Takahashi, Kenta, Ito, Mutsumi, Yamada, Shinya, Fan, Shufang, Chiba, Shiho, Kuroda, Makoto, Guan, Lizheng, Takada, Kosuke, Armbrust, Tammy, Balogh, Aaron, Furusawa, Yuri, Okuda, Moe, Ueki, Hiroshi, Yasuhara, Atsuhiro, Sakai-Tagawa, Yuko, Lopes, Tiago J. S., Kiso, Maki, Yamayoshi, Seiya, Kinoshita, Noriko, Ohmagari, Norio, Hattori, Shin-ichiro, Takeda, Makoto, Mitsuya, Hiroaki, Krammer, Florian, Suzuki, Tadaki, and Kawaoka, Yoshihiro

Published
2020

28. ACE2-like carboxypeptidase B38-CAP protects from SARS-CoV-2-induced lung injury

Author

Yamaguchi, Tomokazu, Hoshizaki, Midori, Minato, Takafumi, Nirasawa, Satoru, Asaka, Masamitsu N., Niiyama, Mayumi, Imai, Masaki, Uda, Akihiko, Chan, Jasper Fuk-Woo, Takahashi, Saori, An, Jianbo, Saku, Akari, Nukiwa, Ryota, Utsumi, Daichi, Kiso, Maki, Yasuhara, Atsuhiro, Poon, Vincent Kwok-Man, Chan, Chris Chung-Sing, Fujino, Yuji, Motoyama, Satoru, Nagata, Satoshi, Penninger, Josef M., Kamada, Haruhiko, Yuen, Kwok-Yung, Kamitani, Wataru, Maeda, Ken, Kawaoka, Yoshihiro, Yasutomi, Yasuhiro, Imai, Yumiko, and Kuba, Keiji

Published
2021
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29. Influenza A variants with reduced susceptibility to baloxavir isolated from Japanese patients are fit and transmit through respiratory droplets

Author

Imai, Masaki, Yamashita, Makoto, Sakai-Tagawa, Yuko, Iwatsuki-Horimoto, Kiyoko, Kiso, Maki, Murakami, Jurika, Yasuhara, Atsuhiro, Takada, Kosuke, Ito, Mutsumi, Nakajima, Noriko, Takahashi, Kenta, Lopes, Tiago J. S., Dutta, Jayeeta, Khan, Zenab, Kriti, Divya, van Bakel, Harm, Tokita, Akifumi, Hagiwara, Haruhisa, Izumida, Naomi, Kuroki, Haruo, Nishino, Tamon, Wada, Noriyuki, Koga, Michiko, Adachi, Eisuke, Jubishi, Daisuke, Hasegawa, Hideki, and Kawaoka, Yoshihiro

Published
2020
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31. Development of a Mouse-Adapted Reporter SARS-CoV-2 as a Tool for Two-Photon In Vivo Imaging.

Author

Ueki, Hiroshi, Kiso, Maki, Furusawa, Yuri, Iida, Shun, Yamayoshi, Seiya, Nakajima, Noriko, Imai, Masaki, Suzuki, Tadaki, and Kawaoka, Yoshihiro

Subjects
SARS-CoV-2, COVID-19
Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) often causes severe viral pneumonia. Although many studies using mouse models have examined the pathogenicity of SARS-CoV-2, COVID-19 pathogenesis remains poorly understood. In vivo imaging analysis using two-photon excitation microscopy (TPEM) is useful for elucidating the pathology of COVID-19, providing pathological insights that are not available from conventional histological analysis. However, there is no reporter SARS-CoV-2 that demonstrates pathogenicity in C57BL/6 mice and emits sufficient light intensity for two-photon in vivo imaging. Here, we generated a mouse-adapted strain of SARS-CoV-2 (named MASCV2-p25) and demonstrated its efficient replication in the lungs of C57BL/6 mice, causing fatal pneumonia. Histopathologic analysis revealed the severe inflammation and infiltration of immune cells in the lungs of MASCV2-p25-infected C57BL/6 mice, not unlike that observed in COVID-19 patients with severe pneumonia. Subsequently, we generated a mouse-adapted reporter SARS-CoV-2 (named MASCV-Venus-p9) by inserting the fluorescent protein-encoding gene Venus into MASCV2-p25 and sequential lung-to-lung passages in C57BL/6 mice. C57BL/6 mice infected with MASCV2-Venus-p9 exhibited severe pneumonia. In addition, the TPEM of the lungs of the infected C57BL/6J mice showed that the infected cells emitted sufficient levels of fluorescence for easy observation. These findings suggest that MASCV2-Venus-p9 will be useful for two-photon in vivo imaging studies of the pathogenesis of severe COVID-19 pneumonia. [ABSTRACT FROM AUTHOR]

Published
2024
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35. Emergence of Oseltamivir-Resistant H7N9 Influenza Viruses in Immunosuppressed Cynomolgus Macaques

Author

Kiso, Maki, Iwatsuki-Horimoto, Kiyoko, Yamayoshi, Seiya, Uraki, Ryuta, Ito, Mutsumi, Nakajima, Noriko, Yamada, Shinya, Imai, Masaki, Kawakami, Eiryo, Tomita, Yuriko, Fukuyama, Satoshi, Itoh, Yasushi, Ogasawara, Kazumasa, Lopes, Tiago J. S., Watanabe, Tokiko, Moncla, Louise H., Hasegawa, Hideki, Friedrich, Thomas C., Neumann, Gabriele, and Kawaoka, Yoshihiro

Published
2017

37. Cardiomyopathy Does Not Exacerbate the Severity of Pneumonia Caused by a SARS-CoV-2 Delta Variant in the J2N-k Hamster Model.

Author

Iwatsuki-Horimoto, Kiyoko, Ito, Mutsumi, Okuda-Hamabata, Moe, Takagi, Hisayoshi, Imai, Masaki, and Kawaoka, Yoshihiro

Subjects
SARS-CoV-2 Delta variant, COVID-19, CARDIOMYOPATHIES, HAMSTERS, CARDIOVASCULAR diseases
Abstract

Cardiovascular disease is one of many risk factors that have been linked to increased severity or mortality in coronavirus disease 2019 (COVID-19) patients; however, the exact role of SARS-CoV-2 in the pathogenesis of cardiac inflammatory injury has not been established. A previous study reported that SARS-CoV-2 causes more severe disease with cardiomyopathy in a J2N-k animal model. Here, we investigated the sensitivity of J2N-k hamsters, as a cardiomyopathy animal model, to a delta strain of SARS-CoV-2 compared to J2N-n control animals. We found that J2N-k hamsters were less susceptible to this delta strain than J2N-n animals, and we found no evidence that cardiomyopathy is a risk factor in this animal model. Since the previous study reported that SARS-CoV-2 causes more severe disease with cardiomyopathy in the same animal model, further analysis of the relationship between cardiomyopathy and SARS-CoV-2 infection is needed. [ABSTRACT FROM AUTHOR]

Published
2023
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38. Characterization of a Feline Influenza A(H7N2) Virus

Author

Hatta, Masato, Zhong, Gongxun, Gao, Yuwei, Nakajima, Noriko, Fan, Shufang, Chiba, Shiho, Deering, Kathleen M., Ito, Mutsumi, Imai, Masaki, Kiso, Maki, Nakatsu, Sumiho, Lopes, Tiago J., Thompson, Andrew J., McBride, Ryan, Suarez, David L., Macken, Catherine A., Sugita, Shigeo, Neumann, Gabriele, Hasegawa, Hideki, Paulson, James C., Toohey-Kurth, Kathy L., and Kawaoka, Yoshihiro

Subjects
Influenza viruses -- Research, Disease transmission -- Research, Virus replication -- Research, Cat diseases -- Research, Health
Abstract

Influenza A viruses are endemic in humans and enzootic in other mammalian species including swine and horses; occasional infections of other mammalian species including whales, seals, sea lions, felidae in [...]

Published
2018
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39. The trajectory of non‐depressed suicidal ideation in community‐dwelling older people in a rural area in Japan: a prospective longitudinal study with a 3‐year follow‐up.

Author

Ichiki, Takahiro, Koyama, Asuka, Imai, Masaki, Nishi, Yoshitomo, Abe, Yasuhisa, Fukunaga, Ryuta, Murakami, Ryoji, Nagaoka, Maiko, Takebayashi, Minoru, and Fujise, Noboru

Subjects
MENTAL depression risk factors, SUICIDE risk factors, GERIATRIC psychiatry, CONFIDENCE intervals, ALCOHOLISM, RURAL conditions, SELF-evaluation, MULTIVARIATE analysis, DISEASE incidence, HEALTH status indicators, SUICIDAL ideation, RISK assessment, PSYCHOLOGICAL tests, SEX distribution, COMPARATIVE studies, T-test (Statistics), SLEEP disorders, INDEPENDENT living, MENTAL depression, QUESTIONNAIRES, DESCRIPTIVE statistics, QUALITY of life, CHI-squared test, FINANCIAL stress, LOGISTIC regression analysis, ODDS ratio, DATA analysis software, LONGITUDINAL method, OLD age
Abstract

Background: Suicidal ideation is closely related to severe suicidal behaviour and is an important predictor of suicide attempt and completion, including in older people. Older people tend to have many opportunities to be conscious of death, and may have vague suicidal ideation because of various loss experiences, even if they are not depressed. We hypothesised that suicidal ideation among older people might be a risk factor for later transition to depression. The present study aimed to clarify risk factors that predict the incidence of depression in older people 3 years post‐baseline in a rural area of Japan, and to examine the subsequent course of depression among non‐depressed older people with suicidal ideation. Methods: In 2015 and 2018, survey questionnaires were mailed to residents aged 65 years and over living in a rural area in Japan. Participants were divided into a depression group and a non‐depression group using 15‐item Geriatric Depression Scale scores 3 years post‐baseline. Logistic regression analysis was used to identify predictive factors of late‐life depression 3 years post‐baseline. Results: We received 597 valid responses, with a 3‐year follow‐up rate of 78.8%. Regarding suicidal ideation, 6.7% of non‐depressed older people exhibited suicidal ideation at baseline. Of these, 9.8% exhibited depression after 3 years post‐baseline. Logistic regression analysis indicated that development of late‐life depression is significantly associated with suicidal ideation, being female, and poor health‐related quality of life (HRQOL). Conclusions: The results revealed that suicidal ideation, being female, and poor HRQOL were predictive factors of the development of late‐life depression 3 years post‐baseline in a rural area of Japan. These findings provide novel information regarding the transition to depression among community‐dwelling older people who are not depressed but have suicidal ideation. Whereas suicidal ideation is considered to be a symptom of depression, the current results suggest that suicidal ideation may precede depression in some older people. [ABSTRACT FROM AUTHOR]

Published
2023
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40. Magnetic Phases in Sr1-x CaxCo2P2 Studied by μ+ SR

Author

Sugiyama, Jun, Nozaki, Hiroshi, Harada, Masashi, Umegaki, Izumi, Higuchi, Yuki, Miwa, Kazutoshi, Imai, Masaki, Michioka, Chishiro, Yoshimura, Kazuyoshi, Ansaldo, Eduardo J., Brewer, Jess H., Andreica, Daniel, Baines, Christopher, and Mansson, Martin

Published
2015
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42. Research article antibody induction and immune response in nasal cavity by third dose of SARS-CoV-2 mRNA vaccination.

Author

Ishizaka, Aya, Koga, Michiko, Mizutani, Taketoshi, Uraki, Ryuta, Yamayoshi, Seiya, Iwatsuki-Horimoto, Kiyoko, Yamamoto, Shinya, Imai, Masaki, Tsutsumi, Takeya, Suzuki, Yutaka, Kawaoka, Yoshihiro, and Yotsuyanagi, Hiroshi

Subjects
NASAL cavity, IMMUNE response, SARS-CoV-2, NASAL mucosa, MESSENGER RNA, IMMUNOGLOBULINS
Abstract

Background: The mucosa serves as the first defence against pathogens and facilitates the surveillance and elimination of symbiotic bacteria by mucosal immunity. Recently, the mRNA vaccine against SARS-CoV-2 has been demonstrated to induce secretory antibodies in the oral and nasal cavities in addition to a systemic immune response. However, the mechanism of induced immune stimulation effect on mucosal immunity and commensal bacteria profile remains unclear. Methods: Here, we longitudinally analysed the changing nasal microbiota and both systemic and nasal immune response upon SARS-CoV-2 mRNA vaccination, and evaluated how mRNA vaccination influenced nasal microbiota in 18 healthy participants who had received the third BNT162b. Results: The nasal S-RBD IgG level correlated significantly with plasma IgG levels until 1 month and the levels were sustained for 3 months post-vaccination. In contrast, nasal S-RBD IgA induction peaked at 1 month, albeit slightly, and correlated only with plasma IgA, but the induction level decreased markedly at 3 months post-vaccination. 16 S rRNA sequencing of the nasal microbiota post-vaccination revealed not an overall change, but a decrease in certain opportunistic bacteria, mainly Fusobacterium. The decrease in these bacteria was more pronounced in those who exhibited nasal S-RBD IgA induction, and those with higher S-RBD IgA induction had lower relative amounts of potentially pathogenic bacteria such as Pseudomonas pre-vaccination. In addition, plasma and mucosal S-RBD IgG levels correlated with decreased commensal pathogens such as Finegoldia. Conclusions: These findings suggest that the third dose of SARS-CoV-2 mRNA vaccination induced S-RBD antibodies in the nasal mucosa and may have stimulated mucosal immunity against opportunistic bacterial pathogens. This effect, albeit probably secondary, may be considered one of the benefits of mRNA vaccination. Furthermore, our data suggest that a cooperative function of mucosal and systemic immunity in the reduction of bacteria and provides a better understanding of the symbiotic relationship between the host and bacteria in the nasal mucosa. [ABSTRACT FROM AUTHOR]

Published
2023
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43. In vitro and in vivo characterization of SARS-CoV-2 strains resistant to nirmatrelvir.

Author

Kiso, Maki, Furusawa, Yuri, Uraki, Ryuta, Imai, Masaki, Yamayoshi, Seiya, and Kawaoka, Yoshihiro

Subjects
SARS-CoV-2 Omicron variant, SARS-CoV-2 Delta variant, SARS-CoV-2, ANTIVIRAL agents, PUBLIC health
Abstract

Nirmatrelvir, an oral antiviral agent that targets a SARS-CoV-2 main protease (3CLpro), is clinically useful against infection with SARS-CoV-2 including its omicron variants. Since most omicron subvariants have reduced sensitivity to many monoclonal antibody therapies, potential SARS-CoV-2 resistance to nirmatrelvir is a major public health concern. Several amino acid substitutions have been identified as being responsible for reduced susceptibility to nirmatrelvir. Among them, we selected L50F/E166V and L50F/E166A/L167F in the 3CLpro because these combinations of substitutions are unlikely to affect virus fitness. We prepared and characterized delta variants possessing Nsp5-L50F/E166V and Nsp5-L50F/E166A/L167F. Both mutant viruses showed decreased susceptibility to nirmatrelvir and their growth in VeroE6/TMPRSS2 cells was delayed. Both mutant viruses showed attenuated phenotypes in a male hamster infection model, maintained airborne transmissibility, and were outcompeted by wild-type virus in co-infection experiments in the absence of nirmatrelvir, but less so in the presence of the drug. These results suggest that viruses possessing Nsp5-L50F/E166V and Nsp5-L50F/E166A/L167F do not become dominant in nature. However, it is important to closely monitor the emergence of nirmatrelvir-resistant SARS-CoV-2 variants because resistant viruses with additional compensatory mutations could emerge, outcompete the wild-type virus, and become dominant. Resistance to nirmatrelvir, an oral antiviral agent that targets SARS-CoV-2 and is clinically useful against infection with Omicron variants, is currently not well understood. In this study, the authors characterize mutant viruses with reduced sensitivity to nirmatrelvir in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Published
2023
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44. Peritoneal Expression of Membrane Complement Regulators Is Decreased in Peritoneal Dialysis Patients with Infected Peritonitis.

Author

Fukui, Sosuke, Mizuno, Masashi, Tawada, Mitsuhiro, Suzuki, Yasuhiro, Kojima, Hiroshi, Matsukawa, Yoshihisa, Imai, Masaki, Kim, Hangsoo, Kinashi, Hiroshi, Mizutani, Makoto, Minoshima, Kenichi, Maruyama, Shoichi, and Ito, Yasuhiko

Subjects
PERITONEAL dialysis, PERITONITIS, HEMODIALYSIS patients, PSEUDOMONAS aeruginosa, SOFT tissue injuries
Abstract

In peritoneal dialysis (PD) patients, fungi and Pseudomonas aeruginosa are considered important causative microorganisms for peritonitis with poor prognosis. Our objective was to explore expressions of membrane complement (C) regulators (CRegs) and tissue injuries in the peritoneum of patients with PD-related peritonitis, including fungal and Pseudomonas aeruginosa peritonitis. In peritoneal biopsy tissues obtained at PD catheter removal, we investigated the severity of peritonitis-associated peritoneal injuries and the expression of CRegs, CD46, CD55, and CD59 against peritoneal tissues without any episode of peritonitis. In addition, we evaluated peritoneal injuries among fungal and Pseudomonas aeruginosa-peritonitis (P1) and Gram-positive bacterial peritonitis (P2). We also observed deposition of C activation products such as activated C and C5b-9 and measured sC5b-9 in the PD fluid of patients. As a result, the severity of peritoneal injuries correlated inversely with the expression of peritoneal CRegs. Peritoneal CReg expression in peritonitis was significantly reduced compared to no peritonitis. Peritoneal injuries were more severe in P1 than in P2. CReg expression was further decreased and C5b-9 further increased in P1 than in P2. In conclusion, severe peritoneal injuries due to fungal and Pseudomonas aeruginosa-peritonitis decreased CReg expression and increased deposition of activated C3 and C5b-9 in the peritoneum, suggesting that peritonitis, particularly fungal and Pseudomonas aeruginosa-peritonitis, might induce susceptibility to further peritoneal injuries due to excessive C activation. [ABSTRACT FROM AUTHOR]

Published
2023
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45. Temperature-variable apparatus for measuring Barnett field.

Author

Umeda, Maki, Chudo, Hiroyuki, Imai, Masaki, Sato, Nana, and Saitoh, Eiji

Subjects
MAGNETIC sensors, LOW temperatures, MAGNETIC susceptibility, SOLENOIDS
Abstract

We have developed experimental equipment for observing the Barnett effect, in which mechanical rotation magnetizes an object, at low temperatures. A sample in a rotor is rotated bidirectionally using a temperature-controlled high-pressure gas. The stray field generated from the sample due to the Barnett effect was detected using a fluxgate magnetic sensor with a sensitivity on the order of several picoteslas, even at low temperatures. By replacing the rotor with a solenoid coil, the magnetic susceptibility of the sample was estimated from the stray field to be of the same order of magnitude as that due to the Barnett effect. The Barnett field was estimated using the dipole model. To assess the performance of the setup at low temperatures, measurements were performed on commercial magnetite (Fe3O4) nanogranules. We confirmed the accordance of the g′ factor between the experimental results using the present setup and those of our previous study performed at room temperature. [ABSTRACT FROM AUTHOR]

Published
2023
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47. Mature dendritic cells enriched in regulatory molecules may control regulatory T cells and the prognosis of head and neck cancer.

Author

Minohara, Kiyoshi, Imai, Masaki, Matoba, Takuma, Wing, James Badger, Shime, Hiroaki, Odanaka, Mizuyu, Uraki, Ryuta, Kawakita, Daisuke, Toyama, Tatsuya, Takahashi, Satoru, Morita, Akimichi, Murakami, Shingo, Ohkura, Naganari, Sakaguchi, Shimon, Iwasaki, Shinichi, and Yamazaki, Sayuri

Abstract

We previously reported that regulatory T (Treg) cells expressing CTLA‐4 on the cell surface are abundant in head and neck squamous cell carcinoma (HNSCC). The role of expanded Treg cells in the tumor microenvironment of HNSCC remains unclear. In this study, we reveal that the tumor microenvironment of HNSCC is characterized by the high expression of genes related to Treg cells, dendritic cells (DCs), and interleukin (IL)‐17‐related molecules. Increased expression of IL17A, IL17F, or IL23A contributes to a favorable prognosis of HNSCC. In the tumor microenvironment of HNSCC, IL23A and IL12B are expressed in mature dendritic cells enriched in regulatory molecules (mregDCs). The mregDCs in HNSCC are a migratory and mature phenotype; their signature genes strongly correlate with Treg signature genes in HNSCC. We also observed that IL17A was highly expressed in Th17 cells and exhausted CD8+ T cells in HNSCC. These data suggest that mregDCs in HNSCC may contribute to the prognosis by balancing Treg cells and effector T cells that produce IL‐17. Targeting mregDCs may be a novel strategy for developing new immune therapies against HNSCC. [ABSTRACT FROM AUTHOR]

Published
2023
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49. Cross-Protection against H5N1 Influenza Virus Infection Is Afforded by Intranasal Inoculation with Seasonal Trivalent Inactivated Influenza Vaccine

Author

Ichinohe, Takeshi, Tamura, Shin-ichi, Kawaguchi, Akira, Ninomiya, Ai, Imai, Masaki, Itamura, Shigeyuki, Odagiri, Takato, Tashiro, Masato, Takahashi, Hidehiro, Sawa, Hirofumi, Mitchell, William M., Strayer, David R., Carter, William A., Chiba, Joe, Kurata, Takeshi, Sata, Tetsutaro, and Hasegawa, Hideki

Published
2007
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