关键词： bat-derived influenza-like virus   hemagglutinin (HA)   neuraminidase (NA)   PA   reassortment   H17N10   H18N11  

摘要： Shorebirds and waterfowls are believed to be the reservoir hosts for influenza viruses, whereas swine putatively act as mixing vessels. The recent identification of two influenza-like virus genomes (designated H17N10 and H18N11) from bats has challenged this notion. A crucial question concerns the role bats might play in influenza virus ecology. Structural and functional studies of the two major surface envelope proteins, hemagglutinin (HA) and neuraminidase (NA), demonstrate that neither has canonical HA or NA functions found in influenza viruses. However, putative functional modules and domains in other encoded proteins are conserved, and the N-terminal domain of the H17N10 polymerase subunit PA has a classical structure and function. Therefore, potential genomic reassortments of such influenza-like viruses with canonical influenza viruses cannot be excluded at this point and should be assessed.

关键词： African Henipavirus   Henipavirus glycoproteins   Zoonoses  

摘要： The recent discovery of a wide range of henipavirus-like viruses circulating in Megabats in Africa raises the question as to the zoonotic potential of these pathogens given the high human mortality rates seen with their pathogenic relatives Nipah virus and Hendra virus. In the absence of cultured infectious African Henipavirus we have performed experiments with recombinant F and G glycoproteins from the representative African Henipavirus strain M74a aimed at estimating its cellular tropism and capacity to use similar receptors to its highly pathogenic counterparts. The ability of the M74a virus G surface protein to use the ubiquitous Ephrin B2 host cell receptor and its heterologous cross-compatibility with Nipah virus could be expected to impart upon this virus a reasonable potential for species spillover, although differences in fusion efficiency seen with the M74a virus F protein in certain cell lines could present a barrier for zoonotic transmission. (C) 2014 Elsevier B.V. All rights reserved.

关键词： ACE2受体   SARS   样冠状病毒   分离   鉴定  

摘要： 2002年3月由严重急性呼吸综合征冠状病毒（severeacuterespiratorysyndromecoronavirus，***）导致的疫情大流行无疑是当代最受关注的公共卫生事件。近来中东呼吸综合征冠状病毒（MiddleEastrespiratorysyndromecoronavirus）疫情的爆发表明这类病毒仍然具有很大威胁，而且其分布比预期的更加广泛。尽管蝙蝠被认为是这2种冠状病毒的自然宿主，但是目前仍未能从蝙蝠中分离出SARS-CoY的祖先病毒（progenitorvires）。据报道，在中国、欧洲和非洲的蝙蝠中曾经发现了多种SARS样冠状病毒（SARS-likecomnavimses，SL-CoVs），但是它们都不是SARS冠状病毒的直接祖先，。因为其系统发生与SARSCoY不一致，而且其突起蛋白都不能利用***的细胞受体分子，

关键词： THROMBOCYTOPENIA   ROUSETTUS leschenaultii   ELECTRON microscopy   ECOLOGY   ZOONOSES  

摘要： During a survey in the year 2010, a novel phlebovirus was isolated from the Rousettus leschenaultii species of bats in western India. The virus was identified by electron microscopy from infected Vero E6 cells. Phylogenic analysis of the complete genome showed its close relation to severe fever with thrombocytopenia syndrome (SFTS) and Heartland viruses, which makes it imperative to further study its natural ecology and potential as a novel emerging zoonotic virus.

关键词： HEK293T Cell   Early Endosome   Endocytic Pathway   Dominant Negative   Infectious Hematopoietic Necrosis Virus  

摘要： Background: Australian bat lyssavirus (ABLV), a rhabdovirus of the genus Lyssavirus which circulates in both pteropid fruit bats and insectivorous bats in mainland Australia, has caused three fatal human infections, the most recent in February 2013, manifested as acute neurological disease indistinguishable from clinical rabies. Rhabdoviruses infect host cells through receptor-mediated endocytosis and subsequent pH-dependent fusion mediated by their single envelope glycoprotein (G), but the specific host factors and pathways involved in ABLV entry have not been determined. Methods: ABLV internalization into HEK293T cells was examined using maxGFP-encoding recombinant vesicular stomatitis viruses (rVSV) that express ABLV G glycoproteins. A combination of chemical and molecular approaches was used to investigate the contribution of different endocytic pathways to ABLV entry. Dominant negative Rab GTPases were used to identify the endosomal compartment utilized by ABLV to gain entry into the host cell cytosol. Results: Here we show that ABLV G-mediated entry into HEK293T cells was significantly inhibited by the dynamin-specific inhibitor dynasore, chlorpromazine, a drug that blocks clathrin-mediated endocytosis, and the actin depolymerizing drug latrunculin B. Over expression of dominant negative mutants of Eps15 and Rab5 also significantly reduced ABLV G-mediated entry into HEK293T cells. Chemical inhibitors of caveolae-dependent endocytosis and macropinocytosis and dominant negative mutants of Rab7 and Rab11 had no effect on ABLV entry. Conclusions: The predominant pathway utilized by ABLV for internalization into HEK293T cells is clathrin-and actin-dependent. The requirement of Rab5 for productive infection indicates that ABLV G-mediated fusion occurs within the early endosome compartment.

关键词： HIV (Viruses)   RESEARCH   ENDONUCLEASES -- Regulation   INFLUENZA   HEMAGGLUTININ -- Genetics   NEURAMINIDASE -- Genetics   PATHOGENIC microorganisms   INFLUENZA -- Prevention   SOCIAL aspects  

摘要： Influenza imposes a great burden on society, not only in its seasonal appearance that affects both humans and domesticated animals but also through the constant threat of potential pandemics. Migratory birds are considered to be the reservoir hosts for influenza viruses, but other animals must also be considered. The recently identified influenza-like virus genome, from H17N10 in bats, was shown to be markedly different from genomes of other known influenza viruses, as both its surface glycoproteins hemagglutinin (HA) and neuraminidase (NA) do not have canonical functions. However, no studies on other individual proteins from this particular virus have been reported until now. Here, we describe the structure of the N-terminal domain of PA from H17N10 influenza-like virus at 2.7-angstrom resolution and show that it has a fold similar to those of homologous PA domains present in more familiar influenza A virus strains. Moreover, we demonstrate that it possesses endonuclease activity and that the histidine residue in the active site is essential for this activity. Although this particular influenza virus subtype is probably not infectious for humans (even its virus state has not been confirmed in bats, as only the genome has been sequenced), reassortment of canonical influenza viruses with certain segments from H17N10 cannot be ruled out at this stage. Therefore, further studies are urgently needed for the sake of influenza prevention and control.

关键词： Biology   Computational biology   Emerging viral diseases   Genomics   Metagenomics   Microbiology   Research Article   Veterinary diseases   Veterinary microbiology   Veterinary science   Veterinary virology   Viral classification   Viral transmission and infection   Viral vectors   Virology   Zoonotic diseases  

摘要： The prediction of viral zoonosis epidemics has become a major public health issue. A profound understanding of the viral population in key animal species acting as reservoirs represents an important step towards this goal. Bats harbor diverse viruses, some of which are of particular interest because they cause severe human diseases. However, little is known about the diversity of the global population of viruses found in bats (virome). We determined the viral diversity of five different French insectivorous bat species (nine specimens in total) in close contact with humans. Sequence-independent amplification, high-throughput sequencing with Illumina technology and a dedicated bioinformatics analysis pipeline were used on pooled tissues (brain, liver and lungs). Comparisons of the sequences of contigs and unassembled reads provided a global taxonomic distribution of virus-related sequences for each sample, highlighting differences both within and between bat species. Many viral families were present in these viromes, including viruses known to infect bacteria, plants/fungi, insects or vertebrates, the most relevant being those infecting mammals (Retroviridae, Herpesviridae, Bunyaviridae, Poxviridae, Flaviviridae, Reoviridae, Bornaviridae, Picobirnaviridae). In particular, we detected several new mammalian viruses, including rotaviruses, gammaretroviruses, bornaviruses and bunyaviruses with the identification of the first bat nairovirus. These observations demonstrate that bats naturally harbor viruses from many different families, most of which infect mammals. They may therefore constitute a major reservoir of viral diversity that should be analyzed carefully, to determine the role played by bats in the spread of zoonotic viral infections.

关键词： Animal Diseases/epidemiology   Animal Diseases/immunology   Animal Diseases/virology   Animals   Antibodies, Neutralizing   Antibodies, Viral   Chiroptera/immunology   Chiroptera/virology   Colorado/epidemiology   Female   Male   Rabies/veterinary   Rabies virus/immunology   Risk Factors   Seasons   Seroepidemiologic Studies  

摘要： In 2001-2005 we sampled permanently marked big brown bats (Eptesicus fuscus) at summer roosts in buildings at Fort Collins, Colorado, for rabies virus neutralizing antibodies (RVNA). Seroprevalence was higher in adult females (17.9%, n = 2,332) than males (9.4%, n = 128;P = 0.007) or volant juveniles (10.2%, n = 738;P<0.0001). Seroprevalence was lowest in a drought year with local insecticide use and highest in the year with normal conditions, suggesting that environmental stress may suppress RVNA production in big brown bats. Seroprevalence also increased with age of bat, and varied from 6.2 to 26.7% among adult females at five roosts sampled each year for five years. Seroprevalence of adult females at 17 other roosts sampled for 1 to 4 years ranged from 0.0 to 47.1%. Using logistic regression, the only ranking model in our candidate set of explanatory variables for serological status at first sampling included year, day of season, and a year by day of season interaction that varied with relative drought conditions. The presence or absence of antibodies in individual bats showed temporal variability. Year alone provided the best model to explain the likelihood of adult female bats showing a transition to seronegative from a previously seropositive state. Day of the season was the only competitive model to explain the likelihood of a transition from seronegative to seropositive, which increased as the season progressed. We found no rabies viral RNA in oropharyngeal secretions of 261 seropositive bats or in organs of 13 euthanized seropositive bats. Survival of seropositive and seronegative bats did not differ. The presence of RVNA in serum of bats should not be interpreted as evidence for ongoing rabies infection.

关键词： Animals   Biomarkers/metabolism   Cell Line, Transformed   Chiroptera/virology   Epithelial Cells/pathology   Epithelial Cells/virology   Fluorescent Antibody Technique   Fluorescent Antibody Technique   Geography   Humans   Species Specificity   Trachea/pathology   Virus Diseases/pathology   Virus Diseases/veterinary   Virus Diseases/virology   Viruses/metabolism   Zoonoses/virology  

摘要： Bats have been increasingly recognized as reservoir of important zoonotic viruses. However, until now many attempts to isolate bat-borne viruses in cell culture have been unsuccessful. Further, experimental studies on reservoir host species have been limited by the difficulty of rearing these species. The epithelium of the respiratory tract plays a central role during airborne transmission, as it is the first tissue encountered by viral particles. Although several cell lines from bats were established recently, no well-characterized, selectively cultured airway epithelial cells were available so far. Here, primary cells and immortalized cell lines from bats of the two important suborders Yangochiroptera and Yinpterochiroptera, Carollia perspicillata (Seba's short-tailed bat) and Eidolon helvum (Straw-colored fruit bat), were successfully cultured under standardized conditions from both fresh and frozen organ specimens by cell outgrowth of organ explants and by the use of serum-free primary cell culture medium. Cells were immortalized to generate permanent cell lines. Cells were characterized for their epithelial properties such as expression of cytokeratin and tight junctions proteins and permissiveness for viral infection with Rift-Valley fever virus and vesicular stomatitis virus Indiana. These cells can serve as suitable models for the study of bat-borne viruses and complement cell culture models for virus infection in human airway epithelial cells.

关键词： bats   papillomavirus   evolution   phylogeny   biodiversity   wildlife  

摘要： Papillomaviruses (PVs) are widespread pathogens. However, the extent of PV infections in bats remains largely unknown. This work represents the first comprehensive study of PVs in Iberian bats. We identified four novel PVs in the mucosa of free-ranging Eptesicus serotinus (EserPV1, EserPV2, and EserPV3) and Rhinolophus ferrumequinum (RferPV1) individuals and analyzed their phylogenetic relationships within the viral family. We further assessed their prevalence in different populations of E. serotinus and its close relative E. isabellinus. Although it is frequent to read that PVs co-evolve with their host, that PVs are highly species-specific, and that PVs do not usually recombine, our results suggest otherwise. First, strict virus-host co-evolution is rejected by the existence of five, distantly related bat PV lineages and by the lack of congruence between bats and bat PVs phylogenies. Second, the ability of EserPV2 and EserPV3 to infect two different bat species (E. serotinus and E. isabellinus) argues against strict host specificity. Finally, the description of a second noncoding region in the RferPV1 genome reinforces the view of an increased susceptibility to recombination in the E2-L2 genomic region. These findings prompt the question of whether the prevailing paradigms regarding PVs evolution should be reconsidered.