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Volume 67, Issue 2
Displaying 1-7 of 7 articles from this issue
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Reviews
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Yuta KANAI, Takeshi KOBAYASHI2017 Volume 67 Issue 2 Pages 99-110
Published: December 25, 2017
Released on J-STAGE: October 24, 2018
JOURNAL FREE ACCESSRotavirus (RV), a non-enveloped icosahedral virus containing eleven gene segments of double-stranded RNA, is the leading cause of severe, acute diarrhea among infants and young children worldwide. Safe and effective rotavirus vaccines have been available since 2006, and have markedly reduced the number of deaths by severe gastroenteritis. However, rotaviruses are still responsible for approximately 200,000 deaths annually worldwide. Reverse genetics systems for the manipulation of viral genomes are a powerful approach for studying viral replication and pathogenesis, and for developing vaccines and viral vectors. The understanding of the molecular mechanisms underlying RV pathogenesis, or development of next generation vaccines, has been hampered by the lack of a complete reverse genetics system. Recently, we developed a novel reverse genetics system which enabled recovery of recombinant RVs entirely from cloned cDNAs. This new strategy requires co-expression of a small transmembrane protein that accelerates cell-to-cell fusion and vaccinia virus capping enzyme. In this review, the strategies and history of the development of reverse genetics systems for the family Reoviridae are described.View full abstractDownload PDF (1929K) -
Kazuhiko KATAYAMA2017 Volume 67 Issue 2 Pages 111-120
Published: December 25, 2017
Released on J-STAGE: October 24, 2018
JOURNAL FREE ACCESSNorovirus is the leading cause of acute gastroenteritis worldwide. Since the discovery of human norovirus (HuNoV), an efficient and reproducible norovirus replication system has not been established in cultured cells. Although limited amounts of virus particles can be produced when the HuNoV genome is directly transfected into cells, the HuNoV cycle of infection has not been successfully reproduced in any currently available cell-culture system. Those results imply that the identification of a functional cell-surface receptor for norovirus might be the key to establishing a norovirus culture system. Using a genome-wide CRISPR/Cas9 guide RNA library, we identified murine CD300lf and CD300ld as functional receptors for murine norovirus (MNV). The treatment of susceptible cells with polyclonal antibody against CD300lf significantly reduced the production of viral progeny. Additionally, ectopic CD300lf expression in nonsusceptible cell lines derived from other animal species enabled MNV infection and progeny production, suggesting that CD300lf has potential for dictating MNV host tropism. Furthermore, CD300ld, which has an amino acid sequence in the N-terminal region of its extracellular domain that is highly homologous to that of CD300lf, also functions as a receptor for MNV. Our results indicate that direct interaction of MNV with two cell-surface molecules, CD300lf and CD300ld, dictates permissive noroviral infection.View full abstractDownload PDF (4374K) -
Takamasa INOUE2017 Volume 67 Issue 2 Pages 121-132
Published: December 25, 2017
Released on J-STAGE: October 24, 2018
JOURNAL FREE ACCESSPolyomavirus (Py) is a non-enveloped, double stranded DNA virus that causes a myriad of devastating human diseases for immunocompromised individuals. To cause infection, Py binds to its receptors on the plasma membrane, is endocytosed, and sorts to the endoplasmic reticulum (ER). From here, Py penetrates the ER membrane to reach the cytosol. Ensuing nuclear entry enables the virus to cause infection. How Py penetrates the ER membrane to access the cytosol is a decisive infection step that is enigmatic. In this review, I highlight the mechanisms by which host cell functions facilitate Py translocation across the ER membrane into the cytosol.View full abstractDownload PDF (689K) -
~Evaluation and optimization of anti-hepatitis C virus agents with a mathematical method based on experimental data on virology~Hirofumi OHASHI, Koichi WATASHI2017 Volume 67 Issue 2 Pages 133-142
Published: December 25, 2017
Released on J-STAGE: October 24, 2018
JOURNAL FREE ACCESSRapid development of novel anti-hepatitis C virus (HCV) agents in recent years has greatly improved treatment outcomes. However, such rapid progress in anti-HCV treatment has not allowed us to fully argue the different characteristics of each anti-HCV agent, optimal multidrug combinations, and the selection of treatment enabling to efficiently eliminate drug resistant viruses. We here quantified the intrinsic antiviral effect of 15 anti-HCV agents either clinically available or under developmental phase using a cell culture system, and identified the parameters that represent the antiviral profile of drugs through mathematical analysis. A computer simulation that calculated the antiviral activity and the frequency of mutation rate under dual- and triple-multidrug treatment presented the argument for the advantage of multidrug treatments. In this review, we summarize the novel approaches to evaluate intrinsic antiviral efficacy of drugs by combining the virological and mathematical analyses.View full abstractDownload PDF (2518K)
Special Issue: The frontline of emerging virus research
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Kentaro YOSHII2017 Volume 67 Issue 2 Pages 143-150
Published: December 25, 2017
Released on J-STAGE: October 24, 2018
JOURNAL FREE ACCESSTick-borne encephalitis virus (TBEV) belongs to the Flaviviridae family and Flavivirus genus. TBEV is maintained in transmission cycles between Ixodid ticks and wild mammalian hosts, particularly rodents. A wide range of animal species are also infected with TBEV by the bite of infected ticks, and TBEV infection causes fatal encephalitis in humans. TBEV is endemic widely in the Eurasian continent, and more than 10,000 cases of the disease are reported annually. In Japan, the 1st confirmed case of TBE was reported in the southern area of Hokkaido in 1993, and after 20 years, the 2nd to 4th cases were reported in Hokkaido in 2016 and 2017. Our sero-epizootiological survey indicated endemic foci of TBEV are widely distributed in Hokkaido and that those of TBEV or tick-borne flavivirus outside Hokkaido.
In this review, I introduced recent topics of TBEV including newly developed diagnostic methods, epidemiology and pathogenesis of TBEV.View full abstractDownload PDF (1001K) -
Hirofumi SAWA, Michihito SASAKI, Yasuko ORBA2017 Volume 67 Issue 2 Pages 151-160
Published: December 25, 2017
Released on J-STAGE: October 24, 2018
JOURNAL FREE ACCESSZoonoses originate from pathogens harbored in domestic and wild animals and therefore it is likely impossible to completely eradicate zoonotic diseases. For pre-emptive measures to attempt to predict the emergence of zoonosis outbreaks and the prevention of future epidemics and pandemics, it is imperative to identify natural host animals carrying potential pathogens and elucidate the routes of pathogen transmission into the human population.
Our research team is conducting epidemiological research studies in Zambia and Indonesia for the control of viral zoonotic diseases. In this review, we present the research findings, including the discovery of orthopoxviruses and polyomaviruses in wildlife in Zambia and the identification of herpesviruses in bats in Indonesia among our activities.View full abstractDownload PDF (6148K) -
Shin MURAKAMI, Taisuke HORIMOTO2017 Volume 67 Issue 2 Pages 161-170
Published: December 25, 2017
Released on J-STAGE: October 24, 2018
JOURNAL FREE ACCESSInfluenza viruses have been known to be types A to C, including human seasonal influenza virus and avian influenza virus. In recent years, the influenza D virus, which possesses different characteristics from other types of influenza viruses, infecting livestock cattle and other domestic animals was discovered in the United States. Epidemiological surveys have revealed that influenza D viruses are prevalent throughout the world, including Japan, and are one of the causative agents of bovine respiratory disease complex (BRDC). In this review, we will describe the discovery of influenza D virus, its epidemiological status, its virological characters, and our researches on the epidemic status of influenza D in Japan.View full abstractDownload PDF (1453K)
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