Papers - YAMADA Kentaro
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Localization of the rabies virus antigen in Merkel cells in the follicle-sinus complexes of muzzle skins of rabid dogs
Taichi Shimatsu, Harumi Shinozaki, Kazunori Kimitsuki, Nozomi Shiwa, Daria L. Manalo, Rodolfo C. Perez, Joselito E. Dilig, Kentaro Yamada, Hassadin Boonsriroj, Satoshi Inoue, Chun-Ho Park
JOURNAL OF VIROLOGICAL METHODS 237 40 - 46 2016.11
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV
The direct fluorescent antibody test (dFAT) on fresh brain tissues is the gold standard for rabies virus antigen detection in dogs. However, this method is laborious and holds a high risk of virus exposure for the experimenter. Skin biopsies are useful for the diagnosis of humans and animals. In mammals, the tactile hair, known as the follicle-sinus complex (FSC), is a specialized touch organ that is abundant in the muzzle skin. Each tactile hair is equipped with more than 2,000 sensory nerve endings. Therefore, this organ is expected to serve as an alternative postmortem diagnostic material. However, the target cells and localization of rabies virus antigen in the FSCs remain to be defined. In the present study, muzzle skins were obtained from 60 rabid dogs diagnosed with rabies by dFAT at the Research Institute of Tropical Medicine in the Philippines. In all dogs, virus antigen was clearly detected in a part of the outer root sheath at the level of the ring sinus of the FSCs, and the majority of cells were positive for the Merkel cell (MC) markers cytokeratin 20 and CAM5.2. Our results suggest that MCs in the FSCs of the muzzle skin are a target for virus replication and could serve as a useful alternative specimen source for diagnosis of rabies. (C) 2016 Elsevier B.V. All rights reserved.
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Efficacy of Favipiravir (T-705) in Rabies Postexposure Prophylaxis Reviewed
Kentaro Yamada, Kazuko Noguchi, Takashi Komeno, Yousuke Furuta, Akira Nishizono
JOURNAL OF INFECTIOUS DISEASES 213 ( 8 ) 1253 - 1261 2016.4
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：OXFORD UNIV PRESS INC
Rabies is a fatal encephalitis caused by rabies virus (RABV), and no antiviral drugs for RABV are currently available. We report for the first time the efficacy of favipiravir (T-705) against RABV in vitro and in vivo. T-705 produced a significant, 3-4 log(10) reduction in the multiplication of street and fixed RABV strains in mouse neuroblastoma Neuro-2a cells, with half-maximal inhibitory concentrations of 32.4 mu M and 44.3 mu M, respectively. T-705 significantly improved morbidity and mortality among RABV-infected mice when orally administered at a dose of 300 mg/kg/day for 7 days, beginning 1 hour after inoculation. T-705 significantly reduced the rate of virus positivity in the brain. Furthermore, the effectiveness of T-705 was comparable to that of equine rabies virus immunoglobulin for postexposure prophylaxis. Collectively, our results suggest that T-705 is active against RABV and may serve as a potential alternative to rabies immunoglobulin in rabies postexposure prophylaxis.
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Contribution of the interaction between the rabies virus P protein and I-kappa B kinase epsilon to the inhibition of type I IFN induction signalling
Tatsunori Masatani, Makoto Ozawa, Kentaro Yamada, Naoto Ito, Masayuki Horie, Aya Matsuu, Kosuke Okuya, Kyoko Tsukiyama-Kohara, Makoto Sugiyama, Akira Nishizono
JOURNAL OF GENERAL VIROLOGY 97 ( 2 ) 316 - 326 2016.2
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：MICROBIOLOGY SOC
The P protein of rabies virus (RABV) is known to interfere with the phosphorylation of the host IFN regulatory factor 3 (IRF-3) and to consequently inhibit type I IFN induction. Previous studies, however, have only tested P proteins from laboratory-adapted fixed virus strains, and to the best of our knowledge there is no report about the effect of P proteins from street RABV strains or other lyssaviruses on the IRF-3-mediated type I IFN induction system. In this study, we evaluated the inhibitory effect of P proteins from several RABV strains, including fixed and street virus strains and other lyssaviruses (Lagos bat, Mokola and Duvenhage viruses), on IRF-3 signalling. All P proteins tested inhibited retinoic acid-inducible gene-1 (RIG-I)- and TANK binding kinase 1 (TBK1)-mediated IRF-3-dependent IFN-beta promoter activities. On the other hand, the P proteins from the RABV street strains 1088 and HCM-9, but not from fixed strains Nishigahara (Ni) and CVS-11 and other lyssaviruses tested, significantly inhibited I-kappa B kinase epsilon (IKK epsilon)-inducible IRF-3-dependent IFN-beta promoter activity. Importantly, we revealed that the P proteins from the 1088 and HCM-9 strains, but not from the remaining viruses, interacted with IKK epsilon. By using expression plasmids encoding chimeric P proteins from the 1088 strain and Ni strain, we found that the C-terminal region of the P protein is important for the interaction with IKK epsilon. These findings suggest that the P protein of RABV street strains may contribute to efficient evasion of host innate immunity.
DOI： 10.1099/jgv.0.000362
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Evaluation of Rapid Neutralizing Antibody Detection Test against Rabies Virus in Human Sera.
Nguyen KA, Nguyen TT, Nguyen DV, Ngo GC, Nguyen CN, Yamada K, Noguchi K, Ahmed K, Hoang HD, Nishizono A
Tropical medicine and health 43 ( 2 ) 111 - 116 2015.6
Language：Japanese Publishing type：Research paper (scientific journal)
DOI： 10.2149/tmh.2014-35
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Neurogenic Cardiomyopathy in Rabbits With Experimentally Induced Rabies
S. Kesdangsakonwut, Y. Sunden, K. Yamada, A. Nishizono, H. Sawa, T. Umemura
VETERINARY PATHOLOGY 52 ( 3 ) 573 - 575 2015.5
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：SAGE PUBLICATIONS INC
Cardiomyopathies have been rarely described in rabbits. Here we report myocardial necrosis of the ventricular wall in rabbits with experimentally induced rabies. Myocardial lesions were found only in rabbits with brain lesions, and the severity of the cardiac lesions was proportional to that of the brain lesions. Neither the frequency nor the cumulative dose of anesthesia was related to the incidence or the severity of the myocardial lesions. The myocardial lesions were characterized by degeneration and/or necrosis of myocardial cells and were accompanied by contraction band necrosis, interstitial fibrosis, and infiltration of inflammatory cells. The brain lesions due to rabies virus infection were most prominent in the cerebral cortex, thalamus, hypothalamus, brainstem, and medulla. Rabies virus antigen was not found in the hearts of any rabbits. Based on these findings, the myocardial lesions were classified as neurogenic cardiomyopathy.
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Characterization of street rabies virus variants with an additional N-glycan at position 247 in the glycoprotein Reviewed
Kentaro Yamada, Kazuko Noguchi, Akira Nishizono
ARCHIVES OF VIROLOGY 159 ( 2 ) 207 - 216 2014.2
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：SPRINGER WIEN
Most street rabies virus glycoproteins (G proteins) possess two N-glycosylation sites, at Asn(37) and Asn(319), whereas an additional N-glycosylation site is present in several fixed (laboratory-adapted) rabies virus strains at Asn(247), which suggests that the N-glycosylation addition may be a marker of fixed viruses. In this study, we successfully cloned two street virus strain 1088 variants, N5B#15 and N5B#10-28, in which the G proteins had an additional N-glycan at position 247, and we examined whether these variants were characterized by cell culture adaptation and attenuation after intramuscular inoculation as fixed viruses. N5B#15 had four mutations, i.e., S148P and D247N in the G protein, and T137A and N2046S in the large (L) protein. N5B#10-28 had an additional mutation in the G protein, R196I. Compared with the parental 1088 virus, both variants exhibited highly efficient replication in mouse neuroblastoma-derived NA cells and reduced pathogenicity in adult mice when inoculated intramuscularly, but not intracerebrally. However, this attenuation was not attributable to the induction of strong immune responses.
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Efficient N-glycosylation at position 37, but not at position 146, in the street rabies virus glycoprotein reduces pathogenicity Reviewed
Kentaro Yamada, Kazuko Noguchi, Akira Nishizono
VIRUS RESEARCH 179 169 - 176 2014.1
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV
Most street rabies viruses have two N-glycosylation sites in their glycoproteins (G proteins), i.e., at Asn(37) and Asn(319), but Asn(37) is usually not core-glycosylated in an efficient manner. Previously, we reported the possible roles of single additional N-glycosylations at Asn(194) or Asn(247) in the cell adaptation and reduced pathogenicity of a street rabies virus, which suggest that N-glycosylation is closely related to the evolution of rabies viruses. In this study, we characterized two novel N-glycosylation-modified variants, N5C#7 and N5C#8, which were cloned using the limiting dilution method after serial passaging of the street rabies virus strain 1088 in mouse neuroblastoma-derived NA cells. N5C#7 had an L38R mutation in the G protein, which led to efficient core glycosylation at Asn(37). On the other hand, N5C#8 had a D146N mutation in the G protein, which led to an additional N-glycosylation at position 146. Both variants replicated highly efficiently in NA cells compared with the parental strain. Like the parental strain, both variants caused lethal infections in adult mice after intracerebral inoculation. However, N5C#7 exhibited reduced pathogenicity after intramuscular inoculation, whereas N5C#8 displayed the same level of pathogenicity as the parental strain. In summary, the efficient core glycosylation at position 37 was related to cell adaptation and the reduced pathogenicity of the street rabies virus. By contrast, despite of being related to cell adaptation, the additional N-glycosylation at position 146 did not affect the pathogenicity, which is consistent with a report that street rabies virus strains with N-glycosylation sites at positions 37, 146, and 319 have been isolated from rabid animals. Thus, the results of the present study provide additional evidence that supports the relationship between G protein N-glycosylation and rabies virus evolution. (C) 2013 Elsevier B.V. All rights reserved.
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Human Bocavirus in Patients with Encephalitis, Sri Lanka, 2009-2010
Daisuke Mori, Udaya Ranawaka, Kentaro Yamada, Shaman Rajindrajith, Kazushi Miya, Harsha Kumara Kithsiri Perera, Takashi Matsumoto, Malka Dassanayake, Marcelo Takahiro Mitui, Hisashi Mori, Akira Nishizono, Maria Soderlund-Venermo, Kamruddin Ahmed
EMERGING INFECTIOUS DISEASES 19 ( 11 ) 1859 - 1862 2013.11
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：CENTERS DISEASE CONTROL
We identified human bocavirus (HBoV) DNA by PCR in cerebrospinal fluid from adults and children with encephalitis in Sri Lanka. HBoV types 1, 2, and 3 were identified among these cases. Phylogenetic analysis of HBoV1 strain sequences found no subclustering with strains previously identified among encephalitis cases in Bangladesh.
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Addition of a single N-glycan to street rabies virus glycoprotein enhances virus production Reviewed
Kentaro Yamada, Kazuko Noguchi, Daichi Nonaka, Muneshin Morita, Aiko Yasuda, Hiroaki Kawazato, Akira Nishizono
JOURNAL OF GENERAL VIROLOGY 94 ( Pt 2 ) 270 - 275 2013.2
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：SOC GENERAL MICROBIOLOGY
Most street rabies virus G proteins have two N-glycosylation sites, i.e. Asn(37) and Asn(319), whereas additional sites are found in fixed (laboratory adapted) viruses. In this study, we performed a pseudotyped virus assay using G-deficient rabies virus and demonstrated that single-N-glycan additions to the G protein of street rabies virus strain 1088, which are found in adapted strains, enhanced virus production in neural and non-neural cell lines, while additions to Asn(194) or Asn(247) enhanced production greatly. Moreover, we found that N-glycan additions at Asn(194) or Asn(247) facilitated the production of cell-associated virus. In contrast, deletion of the sequon at Asn(37) reduced viral production, while a deletion at Asn(319) resulted in extensive loss of production. Furthermore, G proteins lacking an N-glycan at Asn(319) failed to fold into their correct structure and lost their fusion activity, indicating that Asn(319) N-glycosylation is important for the functional expression of street virus G proteins.
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Relationship between Virus-Neutralizing Antibody Levels and the Number of Rabies Vaccinations: a Prospective Study of Dogs in Japan
Ippei Watanabe, Kentaro Yamada, Akira Aso, Okio Suda, Takashi Matsumoto, Takaaki Yahiro, Kamruddin Ahmed, Akira Nishizono
JAPANESE JOURNAL OF INFECTIOUS DISEASES 66 ( 1 ) 17 - 21 2013.1
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：NATL INST INFECTIOUS DISEASES
A mass rabies vaccination of dogs has been conducted annually in Japan over the last 60 years. To assess both current levels of rabies virus-neutralizing antibody (VNA) in dogs and the rationale for current vaccination procedures, we used a rapid fluorescent focus inhibition test to determine VNA levels in 756 dogs that had visited animal hospitals in Japan. We found that 51.1% of the dogs that had received 1 rabies vaccination had protective VNA levels (>= 0.5 IU/ml) with a geometric mean of 0.61 IU/ml. In contrast, 97.8% of the dogs that had been vaccinated at least twice had protective VNA levels with a geometric mean of 7.86 IU/ml. Furthermore, 97.9-100% of the dogs vaccinated at least twice retained protective VNA levels into the second year after the last vaccination. Although VNA levels in the dogs vaccinated at least twice tended to decline 2 years after the last vaccination, 78.9% retained protective VNA levels. Thus, the current rabies vaccination schedule provides adequate protection, but the registration system and vaccination schedule needs to be improved to ensure that increased numbers of dogs are vaccinated against rabies.
DOI： 10.7883/yoken.66.17
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Passive carriage of rabies virus by dendritic cells
Senba K., Matsumoto T., Yamada K., Shiota S., Iha H., Date Y., Ohtsubo M., Nishizono A.
SpringerPlus 2 ( 1 ) 1 - 12 2013
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：SpringerPlus
The rabies virus (RABV) is highly neurotropic and it uses evasive strategies to successfully evade the host immune system. Because rabies is often fatal, understanding the basic processes of the virus-host interactions, particularly in the initial events of infection, is critical for the design of new therapeutic approaches to target RABV. Here, we examined the possible role of dendritic cells (DCs) in the transmission of RABV to neural cells at peripheral site of exposure. Viral replication only occurred at a low level in the DC cell line, JAWS II, after its infection with either pathogenic RABV (CVS strain) or low-pathogenic RABV (ERA strain), and no progeny viruses were produced in the culture supernatants. However, both viral genomic RNAs were retained in the long term after infection and maintained their infectivity. The biggest difference between CVS and ERA was in their ability to induce type I interferons. Although the ERA-infected JAWS II cells exhibited cytopathic effect and were apparently killed by normal spleen cells in vitro, the CVS-infected JAWS II cells showed milder cytopathic effect and less lysis when cocultured with spleen cells. Strongly increased expression of major histocompatibility complex classes I, costimulatory molecules (CD80 and CD86), type I interferons and Toll- like receptor 3, and was observed only in the ERA-inoculated JAWS II cells and not in those inoculated with CVS. During the silencing of the cellular immune response in the DCs, the pathogenic CVS strain cryptically maintained an infectious viral genome and was capable of transmitting infectious RABV to permissive neural cells. These findings demonstrate that DCs may play a role in the passive carriage of RABV during natural rabies infections. © 2013 Senba et al.
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Molecular analysis of the mutational effects of Thai street rabies virus with increased virulence in mice after passages in the BHK cell line
Phatthamon Virojanapirom, Pakamatz Khawplod, Artikaya Sawangvaree, Supaporn Wacharapluesadee, Thiravat Hemachudha, Kentaro Yamada, Kinjiro Morimoto, Akira Nishizono
ARCHIVES OF VIROLOGY 157 ( 11 ) 2201 - 2205 2012.11
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：SPRINGER WIEN
QS-BHK-P7, street rabies virus, after passages in the BHK cell line, had an in vitro phenotype that distinguished it from its parental virus. Both viruses caused lethal infection in mice by central nervous system inoculation; however, only QS-BHK-P7 killed mice by the intramuscular route. We found four mutations, S23R and H424P in ectodomain of the glycoprotein (G), I1711 V in the polymerase genes, and another at the non-coding region between the phosphoprotein and matrix protein genes of QS-BHK-P7. None of the mutations in the G gene occurred in previously reported pathogenic determinants. The roles of mutations in particular non-coding regions remain to be elucidated.
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Evaluation of an improved rapid neutralizing antibody detection test (RAPINA) for qualitative and semiquantitative detection of rabies neutralizing antibody in humans and dogs
Akira Nishizono, Kentaro Yamada, Pakamatz Khawplod, Seiji Shiota, Devika Perera, Takashi Matsumoto, Omala Wimalaratne, Marcelo Takahiro Mitui, Kamruddin Ahmed
VACCINE 30 ( 26 ) 3891 - 3896 2012.6
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI LTD
Using the principle of immunochromatography, we previously developed a method called RAPINA (Rapid Neutralizing Antibody detection test) that can measure the level of rabies virus -neutralizing antibody (VNA) in serum samples [Shiota S. Mannen K, Matsumoto T, Yamada K, Yasui T, Takayama K. et al. Development and evaluation of a rapid neutralizing antibody test for rabies. J Virol Methods 2009;161:58-62]. RAPINA is faster, simpler, and easier to perform compared with a virus-neutralizing test or enzyme-linked immunosorbent assay (ELISA). The improved version of RAPINA has greater positive and negative predictive values corresponding to a VNA level of 0.5IU/mL, as recommended by the World Health Organization and the World Organization for Animal Health. To verify the efficacy of this improved method, serum samples were collected from humans and dogs before and after immunization against rabies and were tested in Japan, Sri Lanka, and Thailand.
The results were compared between RAPINA and the true VNA levels measured by the Rapid Fluorescent Focus Inhibition Test (RFFIT). The improved RAPINA accurately predicted seropositivity for 182 of 183 seropositive human samples as assessed by RFFIT (99.5%) and for 138 of 140 RFFIT-negative human samples (98.6%). In dog serum samples, the positive and negative predictive values were 99.7% (345/355) and 95.6% (174/182), respectively. RAPINA was also used to estimate VNA levels in a semiquantitative manner by using serial dilution of serum samples.
Our results show that RAPINA is an easy and rapid method for measuring VNA levels before and after immunization with the rabies vaccine and does not need a high skill level or sophisticated equipment. RAPINA can be used to monitor the success of preexposure prophylaxis in at-risk persons, vaccine coverage, and animal control. It can also be used in laboratories with modest facilities and where a large number of samples are screened. (C) 2012 Elsevier Ltd. All rights reserved. -
Detection of Human Bocavirus in the Cerebrospinal Fluid of Children With Encephalitis
Marcelo Takahiro Mitui, S. M. Shahnawaz Bin Tabib, Takashi Matsumoto, Wahida Khanam, Selim Ahmed, Daisuke Mori, Nasima Akhter, Kentaro Yamada, Luthful Kabir, Akira Nishizono, Maria Soderlund-Venermo, Kamruddin Ahmed
CLINICAL INFECTIOUS DISEASES 54 ( 7 ) 964 - 967 2012.4
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：OXFORD UNIV PRESS INC
We report 4 children with encephalitis associated with human bocavirus (HBoV) 1 or 2. All children were severely underweight, and 2 died; 1 of them had a matching HBoV2 nucleotide sequence isolated from serum and bocavirus like particles in the cerebrospinal fluid that were observed with electron microscopy. No further pathogens were detected in the cerebrospinal fluid of these patients.
DOI： 10.1093/cid/cir957
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Serial passage of a street rabies virus in mouse neuroblastoma cells resulted in attenuation: Potential role of the additional N-glycosylation of a viral glycoprotein in the reduced pathogenicity of street rabies virus
Kentaro Yamada, Chun-Ho Park, Kazuko Noguchi, Daisuke Kojima, Tatsuya Kubo, Naoyuki Komiya, Takashi Matsumoto, Marcelo Takahiro Mitui, Kamruddin Ahmed, Kinjiro Morimoto, Satoshi Inoue, Akira Nishizono
VIRUS RESEARCH 165 ( 1 ) 34 - 45 2012.4
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV
Street rabies viruses are field isolates known to be highly neurotropic. However, the viral elements related to their pathogenicity have yet to be identified at the nucleotide or amino acid level. Here, through 30 passages in mouse neuroblastoma NA cells, we have established an attenuated variant of street rabies virus strain 1088, originating from a rabid woodchuck followed by 2 passages in the brains of suckling mice. The variant, 1088-N30, was well adapted to NA cells and highly attenuated in adult mice after intramuscular (i.m.) but not intracerebral (i.c.) inoculations. 1088-N30 had seven nucleotide substitutions, and the R196S mutation of the G protein led to an additional N-glycosylation. Street viruses usually possess one or two N-glycosylation sites on the G protein, 1088 has two, while an additional N-glycosylation site is observed in laboratory-adapted strains. We also established a cloned variant 1088-N4#14 by limiting dilution. Apart from the R196S mutation, 1088-N4#14 possessed only one amino acid substitution in the P protein, which is found in several field isolates. 1088-N4#14 also efficiently replicated in NA cells and was attenuated in adult mice after i.m. inoculations, although it was more pathogenic than 1088-N30. The spread of 1088-N30 in the brain was highly restricted after i.m. inoculations., although the pattern of 1088-N4#14's spread was intermediate between that of the parental 1088 and 1088-N30. Meanwhile, both variants strongly induced humoral immune responses in mice compared to 1088. Our results indicate that the additional N-glycosylation is likely related to the reduced pathogenicity. Taken together, we propose that the number of N-glycosylation sites in the G protein is one of the determinants of the pathogenicity of street rabies viruses. (C) 2012 Elsevier B.V. All rights reserved.
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Nishizono A., Yamada K.
Uirusu 62 ( 2 ) 183 - 196 2012
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Uirusu
The family Rhabdoviridae has a non-segmented single stranded negative-sense RNA and its genome ranges in size from approximately 11 kb to almost 16 kb. It is one of the most ecologically diverse families of RNA viruses with members infecting a wide range of organisms. The five structural protein genes are arranged in the same linear order (3'-N-P-M-G-L-5') and may be interspersed with one more additional accessory gene. For many years, a full of knowledge of the rhabdoviridae has been established on extensive studies of two kinds of prototype viruses; vesicular stomatitis virus (VSV) and rabies virus (RABV). Among them, the genus Lyssavirus includes RABV and rabies-related viruses naturally infect mammals and chiropterans via bite-exposure by rabid animals and finally cause fatal encephalitis. In this review, we describe the sketch of the various virological features of the Rhabdoviridae, especially focusing on VSV and RABV.
DOI： 10.2222/jsv.62.183
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The SI Strain of Measles Virus Derived from a Patient with Subacute Sclerosing Panencephalitis Possesses Typical Genome Alterations and Unique Amino Acid Changes That Modulate Receptor Specificity and Reduce Membrane Fusion Activity Reviewed
Fumio Seki, Kentaro Yamada, Yuichiro Nakatsu, Koji Okamura, Yusuke Yanagi, Tetsuo Nakayama, Katsuhiro Komase, Makoto Takeda
JOURNAL OF VIROLOGY 85 ( 22 ) 11871 - 11882 2011.11
Language：English Publishing type：Research paper (scientific journal) Publisher：AMER SOC MICROBIOLOGY
Subacute sclerosing panencephalitis (SSPE) is a fatal sequela associated with measles and is caused by persistent infection of the brain with measles virus (MV). The SI strain was isolated in 1976 from a patient with SSPE and shows neurovirulence in animals. Genome nucleotide sequence analyses showed that the SI strain genome possesses typical genome alterations for SSPE-derived strains, namely, accumulated amino acid substitutions in the M protein and cytoplasmic tail truncation of the F protein. Through the establishment of an efficient reverse genetics system, a recombinant SI strain expressing a green fluorescent protein (rSI-AcGFP) was generated. The infection of various cell types with rSI-AcGFP was evaluated by fluorescence microscopy. rSI-AcGFP exhibited limited syncytium-forming activity and spread poorly in cells. Analyses using a recombinant MV possessing a chimeric genome between those of the SI strain and a wild-type MV strain indicated that the membrane-associated protein genes (M, F, and H) were responsible for the altered growth phenotype of the SI strain. Functional analyses of viral glycoproteins showed that the F protein of the SI strain exhibited reduced fusion activity because of an E300G substitution and that the H protein of the SI strain used CD46 efficiently but used the original MV receptors on immune and epithelial cells poorly because of L482F, S546G, and F555L substitutions. The data obtained in the present study provide a new platform for analyses of SSPE-derived strains as well as a clear example of an SSPE-derived strain that exhibits altered receptor specificity and limited fusion activity.
DOI： 10.1128/JVI.05067-11
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Whole-genome analysis of a human rabies virus from Sri Lanka
Takashi Matsumoto, Kamruddin Ahmed, Omala Wimalaratne, Kentaro Yamada, Susilakanthi Nanayakkara, Devika Perera, Dushantha Karunanayake, Akira Nishizono
ARCHIVES OF VIROLOGY 156 ( 4 ) 659 - 669 2011.4
Language：Japanese Publishing type：Research paper (scientific journal) Publisher：SPRINGER WIEN
The complete genome sequence of a human rabies virus, strain H-08-1320, from Sri Lanka was determined and compared with other rabies viruses. The size of the genome was 11,926 nt, and it was composed of a 58-nucleotide 3' leader, five protein genes - N (1353 nt), P (894 nt), M (609 nt), G (1575 nt), and L (6387 nt) - and a 70-nt 5' trailer. The intergenic region G-L contained 515 nt. The sizes of the nucleoprotein, phosphoprotein, matrix-protein, glycoprotein and large-protein was 450, 296, 202, 524 and 2,128 residues, respectively. The phosphoprotein and large protein were one amino acid shorter and longer, respectively, than those of most rabies viruses. The glycoprotein of H-08-1320 had a unique amino acid substitution at antigenic site I. Whole-genome phylogenetic analysis showed that strain H-08-1320 formed an independent lineage and did not cluster with rabies viruses from other countries.
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A PSAP motif in the ORF3 protein of hepatitis E virus is necessary for virion release from infected cells Reviewed
Shigeo Nagashima, Masaharu Takahashi, Jirintai, Toshinori Tanaka, Kentaro Yamada, Tsutomu Nishizawa, Hiroaki Okamoto
JOURNAL OF GENERAL VIROLOGY 92 ( Pt 2 ) 269 - 278 2011.2
Language：English Publishing type：Research paper (scientific journal) Publisher：SOC GENERAL MICROBIOLOGY
We have previously demonstrated that the release of hepatitis E virus (HEV) from infected cells depended on ORF3 protein, which harbours one or two PSAP motifs. To elucidate the PSAP motif(s) in the ORF3 protein during virion egress, five PSAP mutants derived from an infectious genotype 3 cDNA clone of pJE03-1760F/wt that can grow efficiently in PLC/PRF/5 cells were analysed. Four mutants, including mutLSAP, mutPSAL, mutLSAL (the substituted amino acids in the authentic PSAP motif are underlined) and mutPLAP/PSAP (the changed amino acid in the additional PSAP motif is underlined) generated progenies as efficiently as the wild-type virus. Conversely, the HEV RNA level in the culture supernatant of mutPLAP/LSAL RNA-transfected cells was significantly lower than in cells transfected with the wild-type RNA, similar to an ORF3-null mutant. Consistent with the ORF3-deficient mutant, the mutPLAP/LSAL mutant with no intact PSAP motifs banded at 1.26-1.27 g ml(-1) in sucrose, and was captured by anti-ORF2, but not by anti-ORF3, with or without prior treatment with detergent (0.1% sodium deoxycholate). The absence of the ORF3 protein on the mutant particles in the culture supernatant was confirmed by Western blotting, despite the expression of ORF3 protein in the RNA-transfected cells, as detected by immunofluorescence and Western blotting. Therefore, at least one of the two intact PSAP motifs in the ORF3 protein is required for the formation of membrane-associated HEV particles possessing ORF3 proteins on their surface, thus suggesting that the PSAP motif plays a role as a functional domain for HEV budding.
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Five-year (January 2004-December 2008) surveillance on animal bite and rabies vaccine utilization in the Infectious Disease Hospital, Dhaka, Bangladesh Reviewed
Moazzem Hossain, Tania Bulbul, Kamruddin Ahmed, Ziauddin Ahmed, Mohammad Salimuzzaman, Mohammad Shahidul Haque, Ajmat Ali, Shohrab Hossain, Kentaro Yamada, Kazuhiko Moji, Akira Nishizono
VACCINE 29 ( 5 ) 1036 - 1040 2011.1
Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI LTD
The magnitude of animal bite and utilization of rabies vaccine was determined at the Infectious Disease Hospital, Dhaka, Bangladesh. From January 2004 to December 2008, 150,068 patients with animal bite visited the hospital, 86.2% and 13.8% of them received nerve tissue and tissue culture vaccine (TCV), respectively. Dog bite was most frequent, found in 90.7% cases. In 794 rabies cases only 24.4% had a history of post-exposure vaccination. Only a negligible number of patients received rabies immunoglobulin (RIG). To prevent further human deaths and economic losses intra-dermal TCV regime and equine RIG should be immediately introduced in Bangladesh. (C) 2010 Elsevier Ltd. All rights reserved.