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antibody-mediated neutralization of ebola virus can occur by two distinct mechanisms.human ebola virus causes severe hemorrhagic fever disease with high mortality and there is no vaccine or treatment. antibodies in survivors occur early, are sustained, and can delay infection when transferred into nonhuman primates. monoclonal antibodies (mabs) from survivors exhibit potent neutralizing activity in vitro and are protective in rodents. to better understand targets and mechanisms of neutralization, we investigated a panel of mabs shown previously to react with the envelope glycopr ...201020304456
[stabilization of peroxidase conjugates used in enzyme immunoassay systems to detect ebola and marburg virus antigens].the time course of changes in the activity of solutions of horseradish peroxidase conjugates with immunoglobulins against ebola and marburg fevers was studied in the presence of different components. the series of the conjugates of elisa kits for the detection of ebola and marburg virus antigens, which were prepared on the basis of the designed stabilizing solution, preserved at less than 90% of its baseline activity during 10 months at a storage temperature of 2 to 8 degrees c.201020364672
structural and functional characterization of reston ebola virus vp35 interferon inhibitory domain.ebolaviruses are causative agents of lethal hemorrhagic fever in humans and nonhuman primates. among the filoviruses characterized thus far, reston ebola virus (rebov) is the only ebola virus that is nonpathogenic to humans despite the fact that rebov can cause lethal disease in nonhuman primates. previous studies also suggest that rebov is less effective at inhibiting host innate immune responses than zaire ebola virus (zebov) or marburg virus. virally encoded vp35 protein is critical for immun ...201020399790
development and evaluation of a simple assay for marburg virus detection using a reverse transcription-loop-mediated isothermal amplification method.marburg virus (marv) causes a severe hemorrhagic fever in humans with a high mortality rate. the rapid and accurate identification of the virus is required to appropriately provide infection control and outbreak management. here, we developed and evaluated a one-step reverse transcription-loop-mediated isothermal amplification (rt-lamp) assay for the rapid and simple detection of marv. by combining two sets of primers specific for the musoke and ravn genetic lineages, a multiple rt-lamp assay de ...201020421440
comprehensive panel of real-time taqman polymerase chain reaction assays for detection and absolute quantification of filoviruses, arenaviruses, and new world hantaviruses.viral hemorrhagic fever is caused by a diverse group of single-stranded, negative-sense or positive-sense rna viruses belonging to the families filoviridae (ebola and marburg), arenaviridae (lassa, junin, machupo, sabia, and guanarito), and bunyaviridae (hantavirus). disease characteristics in these families mark each with the potential to be used as a biological threat agent. because other diseases have similar clinical symptoms, specific laboratory diagnostic tests are necessary to provide the ...201020439981
electron tomography reveals the steps in filovirus budding.the filoviruses, marburg and ebola, are non-segmented negative-strand rna viruses causing severe hemorrhagic fever with high mortality rates in humans and nonhuman primates. the sequence of events that leads to release of filovirus particles from cells is poorly understood. two contrasting mechanisms have been proposed, one proceeding via a "submarine-like" budding with the helical nucleocapsid emerging parallel to the plasma membrane, and the other via perpendicular "rocket-like" protrusion. he ...201020442788
both matrix proteins of ebola virus contribute to the regulation of viral genome replication and transcription.ebola virus (ebov) causes severe hemorrhagic fevers in humans and non-human primates. while the role of the ebov major matrix protein vp40 in morphogenesis is well understood, nothing is known about its contributions to the regulation of viral genome replication and/or transcription. similarly, while it was reported that the minor matrix protein vp24 impairs viral genome replication, it remains unclear whether it also regulates transcription, since all common experimental systems measure the com ...201020444481
ebola virus glycoprotein counteracts bst-2/tetherin restriction in a sequence-independent manner that does not require tetherin surface removal.bst-2/tetherin is an interferon-inducible protein that restricts the release of enveloped viruses from the surface of infected cells by physically linking viral and cellular membranes. it is present at both the cell surface and in a perinuclear region, and viral anti-tetherin factors including hiv-1 vpu and hiv-2 env have been shown to decrease the cell surface population. to map the domains of human tetherin necessary for both virus restriction and sensitivity to viral anti-tetherin factors, we ...201020444895
anti-ebola mab 17a3 reacts with bovine and human alpha-2-macroglobulin proteins.monoclonal antibodies (mabs) were developed against soluble ebola virus (ebov) envelope glycoprotein (gp) for the study of the diversity of ebov envelope and development of diagnostic reagents. of the three anti-ebov gp mouse mabs produced, mab 15h10 recognized all human ebov gp species tested (zaire, sudan, ivory coast), and as well as reacted with the reston nonhuman primate ebov gps. a second mab, 6d11 recognized ebov gp species of sudan and sudan-gulu. the third mab, 17a3, was reported origi ...201020447422
inhibition of heat-shock protein 90 reduces ebola virus replication.ebola virus (ebov), a negative-sense rna virus in the family filoviridae, is known to cause severe hemorrhagic fever in humans and other primates. infection with ebov causes a high mortality rate and currently there is no fda-licensed vaccine or therapeutic treatment available. recently, heat-shock protein 90 (hsp90), a molecular chaperone, was shown to be an important host factor for the replication of several negative-strand viruses. we tested the effect of several different hsp90 inhibitors i ...201020452380
effects of the usa patriot act and the 2002 bioterrorism preparedness act on select agent research in the united states.a bibliometric analysis of the bacillus anthracis and ebola virus archival literature was conducted to determine whether negative consequences of the uniting and strengthening america by providing appropriate tools required to intercept and obstruct terrorism" (usa patriot) act and the 2002 bioterrorism preparedness act on us select agent research could be discerned. indicators of the health of the field, such as number of papers published per year, number of researchers authoring papers, and in ...201020457912
oligomerization of ebola virus vp40 is essential for particle morphogenesis and regulation of viral transcription.the morphogenesis and budding of virus particles represent an important stage in the life cycle of viruses. for ebola virus, this process is driven by its major matrix protein, vp40. like the matrix proteins of many other nonsegmented, negative-strand rna viruses, vp40 has been demonstrated to oligomerize and to occur in at least two distinct oligomeric states: hexamers and octamers, which are composed of antiparallel dimers. while it has been shown that vp40 oligomers are essential for the vira ...201020463076
a small-molecule oxocarbazate inhibitor of human cathepsin l blocks severe acute respiratory syndrome and ebola pseudotype virus infection into human embryonic kidney 293t cells.a tetrahydroquinoline oxocarbazate (pubchem cid 23631927) was tested as an inhibitor of human cathepsin l (ec 3.4.22.15) and as an entry blocker of severe acute respiratory syndrome (sars) coronavirus and ebola pseudotype virus. in the cathepsin l inhibition assay, the oxocarbazate caused a time-dependent 17-fold drop in ic(50) from 6.9 nm (no preincubation) to 0.4 nm (4-h preincubation). slowly reversible inhibition was demonstrated in a dilution assay. a transient kinetic analysis using a sing ...201020466822
the great escape: viral strategies to counter bst-2/tetherin.the interferon-induced bst-2 protein has the unique ability to restrict the egress of hiv-1, kaposi's sarcoma-associated herpesvirus (kshv), ebola virus, and other enveloped viruses. the observation that virions remain attached to the surface of bst-2-expressing cells led to the renaming of bst-2 as "tetherin". however, viral proteins such as hiv-1 vpu, simian immunodeficiency virus nef, and kshv k5 counteract bst-2, thereby allowing mature virions to readily escape from infected cells. since th ...201020485522
demonstration of cross-protective vaccine immunity against an emerging pathogenic ebolavirus species.a major challenge in developing vaccines for emerging pathogens is their continued evolution and ability to escape human immunity. therefore, an important goal of vaccine research is to advance vaccine candidates with sufficient breadth to respond to new outbreaks of previously undetected viruses. ebolavirus (ebov) vaccines have demonstrated protection against ebov infection in nonhuman primates (nhp) and show promise in human clinical trials but immune protection occurs only with vaccines whose ...201020502688
are we any closer to combating ebola infections? 201020511001
postexposure protection of non-human primates against a lethal ebola virus challenge with rna interference: a proof-of-concept study.we previously showed that small interfering rnas (sirnas) targeting the zaire ebola virus (zebov) rna polymerase l protein formulated in stable nucleic acid-lipid particles (snalps) completely protected guineapigs when administered shortly after a lethal zebov challenge. although rodent models of zebov infection are useful for screening prospective countermeasures, they are frequently not useful for prediction of efficacy in the more stringent non-human primate models. we therefore assessed the ...201020511019
ebola and marburg hemorrhagic fever.ebola and marburg viruses cause a severe viral hemorrhagic fever disease mainly in sub-saharan africa. although outbreaks are sporadic, there is the potential for filoviruses to spread to other continents unintentionally because of air travel or intentionally because of bioterrorism. this article discusses the natural history, epidemiology, and clinical presentation of patients infected with ebola and marburg viruses. clinicians in the united states should be aware of the symptoms of these viral ...201020513546
a novel l-ficolin/mannose-binding lectin chimeric molecule with enhanced activity against ebola virus.ebola viruses constitute a newly emerging public threat because they cause rapidly fatal hemorrhagic fevers for which no treatment exists, and they can be manipulated as bioweapons. we targeted conserved n-glycosylated carbohydrate ligands on viral envelope surfaces using novel immune therapies. mannose-binding lectin (mbl) and l-ficolin (l-fcn) were selected because they function as opsonins and activate complement. given that mbl has a complex quaternary structure unsuitable for large scale co ...201020516066
crystallization and preliminary x-ray analysis of ebola vp35 interferon inhibitory domain mutant proteins.vp35 is one of seven structural proteins encoded by the ebola viral genome and mediates viral replication, nucleocapsid formation and host immune suppression. the c-terminal interferon inhibitory domain (iid) of vp35 is critical for dsrna binding and interferon inhibition. the wild-type vp35 iid structure revealed several conserved residues that are important for dsrna binding and interferon antagonism. here, the expression, purification and crystallization of recombinant zaire ebola vp35 iid mu ...201020516601
ebola hemorrhagic fever associated with novel virus strain, uganda, 2007-2008.during august 2007-february 2008, the novel bundibugyo ebolavirus species was identified during an outbreak of ebola viral hemorrhagic fever in bundibugyo district, western uganda. to characterize the outbreak as a requisite for determining response, we instituted a case-series investigation. we identified 192 suspected cases, of which 42 (22%) were laboratory positive for the novel species; 74 (38%) were probable, and 77 (40%) were negative. laboratory confirmation lagged behind outbreak verifi ...201020587179
experimental rna therapy shows promise against ebola virus in monkey studies. 201020606143
time to put ebola in context. interview with dr melissa leach.viruses that cause haemorrhagic fevers have been popularized by the media as fierce predators that threaten to devastate global populations. professor melissa leach says there is much to learn from combining local and scientific knowledge in dealing with these deadly pathogens.201020616966
identification of gbv-d, a novel gb-like flavivirus from old world frugivorous bats (pteropus giganteus) in bangladesh.bats are reservoirs for a wide range of zoonotic agents including lyssa-, henipah-, sars-like corona-, marburg-, ebola-, and astroviruses. in an effort to survey for the presence of other infectious agents, known and unknown, we screened sera from 16 pteropus giganteus bats from faridpur, bangladesh, using high-throughput pyrosequencing. sequence analyses indicated the presence of a previously undescribed virus that has approximately 50% identity at the amino acid level to gb virus a and c (gbv- ...201020617167
fibroblastic reticular cell infection by hemorrhagic fever viruses.viral hemorrhagic fevers (vhfs) often cause high mortality with high infectivity, multiorgan failure, shock and hemorrhagic diathesis. fibroblastic reticular cells (frcs) within secondary lymphoid organs provide a supporting scaffold to t-lymphocyte areas. these cells regulate the movement of various immune cells and soluble molecules that promote t-lymphocyte homeostasis. we previously reported ebola virus infection of frcs, but ascribed little significance to this finding. here, we studied inf ...200920635940
development of high-content imaging assays for lethal viral pathogens.filoviruses such as ebola (ebov) and marburg (marv) are single-stranded negative sense rna viruses that cause acute hemorrhagic fever with high mortality rates. currently, there are no licensed vaccines or therapeutics to counter filovirus infections in humans. the development of higher throughput/high-content primary screening assays followed by validation using the low-throughput traditional plaque or real-time pcr assays will greatly aid efforts toward the discovery of novel antiviral therape ...201020639507
genetic factors of ebola virus virulence in guinea pigs.zaire ebolavirus (zebov) causes severe hemorrhagic fever in primates, whereas in guinea pigs it induces a nonlethal infection with a mild fever and subsequent recovery. we performed 7 selective passages in guinea pigs resulted in obtaining of guinea pig-adapted strain (gpa-p7) strain. by the 7th passage, the infection with ebov induced a lethal disease in animals accompanied by the characteristic hematological changes: leukocytosis (primarily due to neutrophilia) as well as pronounced deficienci ...201020654661
prospects for immunisation against marburg and ebola viruses.for more than 30 years the filoviruses, marburg virus and ebola virus, have been associated with periodic outbreaks of hemorrhagic fever that produce severe and often fatal disease. the filoviruses are endemic primarily in resource-poor regions in central africa and are also potential agents of bioterrorism. although no vaccines or antiviral drugs for marburg or ebola are currently available, remarkable progress has been made over the last decade in developing candidate preventive vaccines again ...201020658513
viral haemorrhagic fevers imported into non-endemic countries: risk assessment and management.viral haemorrhagic fevers (vhfs) are severe infections capable of causing haemorrhagic disease and fatal multi-organ failure. crimean-congo, marburg, ebola and lassa viruses cause both sporadic cases and large epidemics over wide endemic areas.201020682627
long-term survival of an urban fruit bat seropositive for ebola and lagos bat viruses.ebolaviruses (ebov) (family filoviridae) cause viral hemorrhagic fevers in humans and non-human primates when they spill over from their wildlife reservoir hosts with case fatality rates of up to 90%. fruit bats may act as reservoirs of the filoviridae. the migratory fruit bat, eidolon helvum, is common across sub-saharan africa and lives in large colonies, often situated in cities. we screened sera from 262 e. helvum using indirect fluorescent tests for antibodies against ebov subtype zaire. we ...201020694141
endogenous cd317/tetherin limits replication of hiv-1 and murine leukemia virus in rodent cells and is resistant to antagonists from primate viruses.human cd317 (bst-2/tetherin) is an intrinsic immunity factor that blocks the release of retroviruses, filoviruses, herpesviruses, and arenaviruses. it is unclear whether cd317 expressed endogenously in rodent cells has the capacity to interfere with the replication of the retroviral rodent pathogen murine leukemia virus (mlv) or, in the context of small-animal model development, contributes to the well-established late-phase restriction of human immunodeficiency virus type 1 (hiv-1). here, we sh ...201020702620
identification of essential filovirion-associated host factors by serial proteomic analysis and rnai screen.an assessment of the total protein composition of filovirus (ebolavirus and marburgvirus) virions is currently lacking. in this study, liquid chromatography-linked tandem mass spectrometry of purified ebola and marburg virions was performed to identify associated cellular proteins. host proteins involved in cell adhesion, cytoskeleton, cell signaling, intracellular trafficking, membrane organization, and chaperones were identified. significant overlap exists between this data set and proteomic s ...201020702783
advanced antisense therapies for postexposure protection against lethal filovirus infections.currently, no vaccines or therapeutics are licensed to counter ebola or marburg viruses, highly pathogenic filoviruses that are causative agents of viral hemorrhagic fever. here we show that administration of positively charged phosphorodiamidate morpholino oligomers (pmoplus), delivered by various dosing strategies initiated 30-60 min after infection, protects>60% of rhesus monkeys against lethal zaire ebola virus (zebov) and 100% of cynomolgus monkeys against lake victoria marburg virus (marv) ...201020729866
viral and host proteins that modulate filovirus budding.the filoviruses, ebola and marburg, utilize a multifaceted mechanism for assembly and budding of infectious virions from mammalian cells. growing evidence not only demonstrates the importance of multiple viral proteins for efficient assembly and budding, but also the exploitation of various host proteins/pathways by the virus during this late stage of filovirus replication, including endocytic compartments, vacuolar protein sorting pathways, ubiquitination machinery, lipid rafts and cytoskeletal ...020730024
cross-platform evaluation of commercial real-time reverse transcription pcr master mix kits using a quantitative 5'nuclease assay for ebola virus.selection of optimal reaction master mix reagents is essential to obtain the best performance with diagnostic real-time reverse transcription polymerase chain reaction (rt-pcr) assays. every year the number of commercially available master mix kits increases, so it is prudent to periodically evaluate kits on the market. in this study we evaluated five commercial real-time rt-pcr master mix kits, the realmastermix rt-pcr rox kit, the agpath-id one-step rt-pcr kit, the superscript iii platinum one ...201020732412
establishment of fruit bat cells (rousettus aegyptiacus) as a model system for the investigation of filoviral infection.the fruit bat species rousettus aegyptiacus was identified as a potential reservoir for the highly pathogenic filovirus marburg virus. to establish a basis for a molecular understanding of the biology of filoviruses in the reservoir host, we have adapted a set of molecular tools for investigation of filovirus replication in a recently developed cell line, r06e, derived from the species rousettus aegyptiacus.201020808767
myeloid cell death associated with toll-like receptor 7/8-mediated inflammatory response. implication of ask1, hif-1 alpha, il-1 beta and tnf-alpha.programmed cell death or apoptosis is an important part of the host innate immune defence, especially against ssrna viruses (influenza virus, hiv-1, ebola virus, hepatitis c virus and many others). viral ssrna is recognised by endosomal toll-like receptors 7 and 8 (tlr7/8) which induce further stages of immune defence against these pathogens. some of the immune cells die because of inflammatory stress allowing for the selection of those cells which are resistant to stress-induced apoptosis and w ...201020828827
persistence in darkness of virulent alphaviruses, ebola virus, and lassa virus deposited on solid surfaces.ebola, lassa, venezuelan equine encephalitis, and sindbis viruses were dried onto solid surfaces, incubated for various time periods under controlled conditions of temperature and relative humidity, and quantitatively eluted from surfaces, and viral titers in the recovered samples were determined. the viral inactivation kinetics that were obtained indicated that viral resistance to natural inactivation in the dark follows (in decreasing order of stability) alphavirus > lassa virus > ebola virus. ...201020842393
steric shielding of surface epitopes and impaired immune recognition induced by the ebola virus glycoprotein.many viruses alter expression of proteins on the surface of infected cells including molecules important for immune recognition, such as the major histocompatibility complex (mhc) class i and ii molecules. virus-induced downregulation of surface proteins has been observed to occur by a variety of mechanisms including impaired transcription, blocks to synthesis, and increased turnover. viral infection or transient expression of the ebola virus (ebov) glycoprotein (gp) was previously shown to resu ...201020844579
enzyme-linked immunosorbent assay for detection of filovirus species-specific antibodies.several enzyme-linked immunosorbent assays (elisas) for the detection of filovirus-specific antibodies have been developed. however, diagnostic methods to distinguish antibodies specific to the respective species of filoviruses, which provide the basis for serological classification, are not readily available. we established an elisa using his-tagged secreted forms of the transmembrane glycoproteins (gps) of five different ebola virus (ebov) species and one marburg virus (marv) strain as antigen ...201020861331
cellular entry of ebola virus involves uptake by a macropinocytosis-like mechanism and subsequent trafficking through early and late endosomes.zaire ebolavirus (zebov), a highly pathogenic zoonotic virus, poses serious public health, ecological and potential bioterrorism threats. currently no specific therapy or vaccine is available. virus entry is an attractive target for therapeutic intervention. however, current knowledge of the zebov entry mechanism is limited. while it is known that zebov enters cells through endocytosis, which of the cellular endocytic mechanisms used remains unclear. previous studies have produced differing outc ...201020862315
association of kir2ds1 and kir2ds3 with fatal outcome in ebola virus infection.zaïre ebolavirus (zebov) infection rapidly outruns the host's immunity and leads to death within a week. fatal cases have been associated with an aberrant innate, proinflammatory immune response followed by a suppressed adaptive response leading to the rapid depletion of peripheral nk cells and lymphocytes. a critical role for nk cells has been suggested but not elucidated. in this genetic study, we investigated the association of kir genotype with disease outcome by comparing genotypes of a gab ...201020878400
ebolavirus is internalized into host cells via macropinocytosis in a viral glycoprotein-dependent manner.ebolavirus (ebov) is an enveloped, single-stranded, negative-sense rna virus that causes severe hemorrhagic fever with mortality rates of up to 90% in humans and nonhuman primates. previous studies suggest roles for clathrin- or caveolae-mediated endocytosis in ebov entry; however, ebolavirus virions are long, filamentous particles that are larger than the plasma membrane invaginations that characterize clathrin- or caveolae-mediated endocytosis. the mechanism of ebov entry remains, therefore, p ...201020886108
[evaluation of ebola virus reproduction in adult icr white mice].the investigators studied the ability of adult icr mice (a laboratory model that was most approximated to the wildtype populations of mice) to maintain ebola virus (ev) reproduction in the organism. the adult icr mice inoculated with ev during 23 passages were shown to maintain viral reproduction in the liver. the elevated levels of platelets and the early generation of fibrin and fibrinogen degradation products suggested there were hemostatic changes that did not, however, progress to severe co ...201020886711
[bats and other reservoir hosts of filoviridae. danger of epidemic on the african continent?--a deductive literature analysis].ebola and marburg virus, forming the filoviridae family, cause hemorrhagic fever in countries of sub-saharan africa. these viral diseases are characterized by a sudden epidemic occurrence as well as a high lethality. even though a reservoir host has not been approved yet, literature indicates the order of bats (chiroptera) as a potential reservoir host. significant references lead to a delineation of a hypothetical ecosystem of filoviridae including chiroptera. igg-specific ebola-zaire antibodie ...201020924703
metagenomic analysis of the viromes of three north american bat species: viral diversity among different bat species that share a common habitat.effective prediction of future viral zoonoses requires an in-depth understanding of the heterologous viral population in key animal species that will likely serve as reservoir hosts or intermediates during the next viral epidemic. the importance of bats as natural hosts for several important viral zoonoses, including ebola, marburg, nipah, hendra, and rabies viruses and severe acute respiratory syndrome-coronavirus (sars-cov), has been established; however, the large viral population diversity ( ...201020926577
identification of novel cellular targets for therapeutic intervention against ebola virus infection by sirna screening.while much progress has been made in developing drugs against a few prominent viruses such as hiv, few examples exist for emerging infectious agents. in some cases broad spectrum anti-viral drugs, such as ribavirin, are effective, but for some groups of viruses, these show little efficacy in animal models. traditional methods focus on screening small molecule libraries to identify drugs that target virus factors, with the intention that side-effects to the host can be minimized. however, this gr ...200920930947
human fatal zaire ebola virus infection is associated with an aberrant innate immunity and with massive lymphocyte apoptosis.ebolavirus species zaire (zebov) causes highly lethal hemorrhagic fever, resulting in the death of 90% of patients within days. most information on immune responses to zebov comes from in vitro studies and animal models. the paucity of data on human immune responses to this virus is mainly due to the fact that most outbreaks occur in remote areas. published studies in this setting, based on small numbers of samples and limited panels of immunological markers, have given somewhat different result ...201020957152
haemorrhagic fever in africa due to marburg-ebola viruses. 197720958370
[treatment of ebola infection with sirna.]. 201020967928
respiratory tract immunization of non-human primates with a newcastle disease virus-vectored vaccine candidate against ebola virus elicits a neutralizing antibody response.we previously developed a respiratory tract vaccine candidate against ebola virus (ebov) based on human parainfluenza virus type 3 (hpiv3), a respiratory paramyxovirus, expressing the ebov gp envelope protein (hpiv3/gp) from an added gene. two doses of this vaccine candidate delivered by the intranasal and intratracheal route protected monkeys against intraperitoneal challenge with ebov; however, concerns exist that the vaccine candidate may have reduced immunogenicity in the adult human populat ...201021034822
a replication defective recombinant ad5 vaccine expressing ebola virus gp is safe and immunogenic in healthy adults.ebola virus causes irregular outbreaks of severe hemorrhagic fever in equatorial africa. case mortality remains high; there is no effective treatment and outbreaks are sporadic and unpredictable. studies of ebola virus vaccine platforms in non-human primates have established that the induction of protective immunity is possible and safety and human immunogenicity has been demonstrated in a previous phase i clinical trial of a 1st generation ebola dna vaccine. we now report the safety and immunog ...201021034824
proposal for a revised taxonomy of the family filoviridae: classification, names of taxa and viruses, and virus abbreviations.the taxonomy of the family filoviridae (marburgviruses and ebolaviruses) has changed several times since the discovery of its members, resulting in a plethora of species and virus names and abbreviations. the current taxonomy has only been partially accepted by most laboratory virologists. confusion likely arose for several reasons: species names that consist of several words or which (should) contain diacritical marks, the current orthographic identity of species and virus names, and the simila ...201021046175
an optofluidic nanoplasmonic biosensor for direct detection of live viruses from biological media.fast and sensitive virus detection techniques, which can be rapidly deployed at multiple sites, are essential to prevent and control future epidemics and bioterrorism threats. in this letter, we demonstrate a label-free optofluidic nanoplasmonic sensor that can directly detect intact viruses from biological media at clinically relevant concentrations with little to no sample preparation. our sensing platform is based on an extraordinary light transmission effect in plasmonic nanoholes and utiliz ...201021053965
shedding of soluble glycoprotein 1 detected during acute lassa virus infection in human subjects.abstract: background: lassa hemorrhagic fever (lhf) is a neglected tropical disease with significant impact on the health care system, society, and economy of western and central african nations where it is endemic. with a high rate of infection that may lead to morbidity and mortality, understanding how the virus interacts with the host's immune system is of great importance for generating vaccines and therapeutics. previous work by our group identified a soluble isoform of the lassa virus (las ...201021062490
towards broad protection against ebolaviruses.the ebola and marburg viruses (from the filovirus family) induce deadly hemorrhagic fevers for which there is currently no licensed vaccine or treatment. frequent outbreaks have occurred in sub-saharan africa, in humans and nonhuman primates over the last 15 years or so and constitute a major public health problem. of particular concern, a new species of ebolavirus recently emerged in uganda, highlighting the high potential of these viruses to evolve and the need to develop 'broad-spectrum' vacc ...201021073307
ebola haemorrhagic fever.ebola viruses are the causative agents of a severe form of viral haemorrhagic fever in man, designated ebola haemorrhagic fever, and are endemic in regions of central africa. the exception is the species reston ebola virus, which has not been associated with human disease and is found in the philippines. ebola virus constitutes an important local public health threat in africa, with a worldwide effect through imported infections and through the fear of misuse for biological terrorism. ebola viru ...201121084112
detection of all known filovirus species by reverse transcription-polymerase chain reaction using a primer set specific for the viral nucleoprotein gene.the filoviruses, marburg virus (marv) and ebola virus (ebov), are causative agents of severe hemorrhagic fever with high mortality rates in humans and non-human primates. sporadic outbreaks of filovirus infection have occurred in central africa and parts of asia. identification of the natural reservoir animals that are unknown yet and epidemiological investigations are current challenges to forestall outbreaks of filovirus diseases. the filovirus species identified currently include one in the m ...201021093485
sensitivity to ultraviolet radiation of lassa, vaccinia, and ebola viruses dried on surfaces.germicidal uv (also known as uvc) provides a means to decontaminate infected environments as well as a measure of viral sensitivity to sunlight. the present study determined uvc inactivation slopes (and derived d(37) values) of viruses dried onto nonporous (glass) surfaces. the data obtained indicate that the uv resistance of lassa virus is higher than that of ebola virus. the uv sensitivity of vaccinia virus (a surrogate for variola virus) appeared intermediate between that of the two virulent ...201021104283
proportion of deaths and clinical features in bundibugyo ebola virus infection, uganda.the first known ebola hemorrhagic fever (ehf) outbreak caused by bundibugyo ebola virus occurred in bundibugyo district, uganda, in 2007. fifty-six cases of ehf were laboratory confirmed. although signs and symptoms were largely nonspecific and similar to those of ehf outbreaks caused by zaire and sudan ebola viruses, proportion of deaths among those infected was lower (≈40%).201021122234
progress in filovirus vaccine development: evaluating the potential for clinical use.marburg and ebola viruses cause severe hemorrhagic fever in humans and nonhuman primates. currently, there are no effective treatments and no licensed vaccines; although a number of vaccine platforms have proven successful in animal models. the ideal filovirus vaccine candidate should be able to provide rapid protection following a single immunization, have the potential to work postexposure and be cross-reactive or multivalent against all marburg virus strains and all relevant ebola virus speci ...201121162622
genome-based in silico identification of new mycobacterium tuberculosis antigens activating polyfunctional cd8+ t cells in human tuberculosis.although cd8(+) t cells help control mycobacterium tuberculosis infection, their m. tuberculosis ag repertoire, in vivo frequency, and functionality in human tuberculosis (tb) remains largely undefined. we have performed genome-based bioinformatics searches to identify new m. tuberculosis epitopes presented by major hla class i supertypes a2, a3, and b7 (covering 80% of the human population). a total of 432 m. tuberculosis peptides predicted to bind to hla-a*0201, hla-a*0301, and hla-b*0702 (rep ...201021169544
ebolavirus vp35 is a multifunctional virulence factor.ebola virus (ebov) is a member of the filoviridae family that causes severe hemorrhagic fever during sporadic outbreaks, and no approved treatments are currently available. the multifunctional ebov vp35 protein facilitates immune evasion by antagonizing antiviral signaling pathways and is important for viral rna synthesis. in order to elucidate regulatory mechanisms and to develop countermeasures, we recently solved the structures of the zaire and reston ebov vp35 interferon inhibitory domain (i ...201021178490
analyses of selex-derived zap-binding rna aptamers suggest that the binding specificity is determined by both structure and sequence of the rna.the zinc-finger antiviral protein (zap) is a host factor that specifically inhibits the replication of certain viruses, including murine leukemia virus, sindbis virus and ebola virus, by targeting the viral mrnas for degradation. zap directly binds to the target viral mrna and recruits the cellular rna degradation machinery to degrade the rna. no significant sequence similarity or obvious common motifs have been found in the so far identified target viral mrnas. the minimum length of the target ...201021203916
discovery, synthesis, and biological evaluation of a novel group of selective inhibitors of filoviral entry.herein, we report the development of an antifiloviral screening system, based on a pseudotyping strategy, and its application in the discovery of a novel group of small molecules that selectively inhibit the ebola and marburg glycoprotein (gp)-mediated infection of human cells. using ebola zaire gp-pseudotyped hiv particles bearing a luciferase reporter gene and 293t cells, a library of 237 small molecules was screened for inhibition of gp-mediated viral entry. from this assay, lead compound 8a ...201121204524
filovirus emergence and vaccine development: a perspective for health care practitioners in travel medicine.recent case reports of viral hemorrhagic fever in europe and the united states have raised concerns about the possibility for increased importation of filoviruses to non-endemic areas. this emerging threat is concerning because of the increase in global air travel and the rise of tourism in central and eastern africa and the greater dispersion of military troops to areas of infectious disease outbreaks. marburg viruses (marv) and ebola viruses (ebov) have been associated with outbreaks of severe ...201021208830
full-length ebola glycoprotein accumulates in the endoplasmic reticulum.the filoviridae family comprises of ebola and marburg viruses, which are known to cause lethal hemorrhagic fever. however, there is no effective anti-viral therapy or licensed vaccines currently available for these human pathogens. the envelope glycoprotein (gp) of ebola virus, which mediates entry into target cells, is cytotoxic and this effect maps to a highly glycosylated mucin-like region in the surface subunit of gp (gp1). however, the mechanism underlying this cytotoxic property of gp is u ...201121223600
effect of flanking residues on the conformational sampling of the internal fusion peptide from ebola virus.fusion peptides mediate viral and host-cell membrane fusion during viral entry. the monomeric form of the internal fusion peptide from ebola virus was studied in membrane bilayer and water environments with computer simulations using replica exchange sampling and an implicit solvent description of the environment. wild-type ebola fusion peptide (efp), the w8a mutant form, and an extended construct with flanking residues were examined. it was found that the monomeric form of wild-type efp adopts ...201121246633
measuring the strength of interaction between the ebola fusion peptide and lipid rafts: implications for membrane fusion and virus infection.the ebola fusion peptide (ebo₁₆) is a hydrophobic domain that belongs to the gp2 membrane fusion protein of the ebola virus. it adopts a helical structure in the presence of mimetic membranes that is stabilized by the presence of an aromatic-aromatic interaction established by trp8 and phe12. in spite of its infectious cycle becoming better understood recently, several steps still remain unclear, a lacuna that makes it difficult to develop strategies to block infection. in order to gain insight ...201121249196
distinct patterns of ifitm-mediated restriction of filoviruses, sars coronavirus, and influenza a virus.interferon-inducible transmembrane proteins 1, 2, and 3 (ifitm1, 2, and 3) are recently identified viral restriction factors that inhibit infection mediated by the influenza a virus (iav) hemagglutinin (ha) protein. here we show that ifitm proteins restricted infection mediated by the entry glycoproteins (gp(1,2)) of marburg and ebola filoviruses (marv, ebov). consistent with these observations, interferon-β specifically restricted filovirus and iav entry processes. ifitm proteins also inhibited ...201121253575
mouse lsectin as a model for a human ebola virus receptor.the biochemical properties of mouse lsectin, a glycan-binding receptor that is a member of the c-type lectin family found on sinusoidal endothelial cells, have been investigated. the c-type carbohydrate-recognition domain of mouse lsectin, expressed in bacteria, has been used in solid-phase binding assays, and a tetramerized form has been used to probe a glycan array. in spite of sequence differences near the glycan-binding sites, the mouse receptor closely mimics the properties of the human rec ...201121257728
liposome-coupled peptides induce long-lived memory cd8 t cells without cd4 t cells.cd8(+) t cells provide broad immunity to viruses, because they are able to recognize all types of viral proteins. therefore, the development of vaccines capable of inducing long-lived memory cd8(+) t cells is desired to prevent diseases, especially those for which no vaccines currently exist. however, in designing cd8(+) t cell vaccines, the role of cd4(+) t cells in the induction and maintenance of memory cd8(+) t cells remains uncertain. in the present study, the necessity or not of cd4(+) t c ...201021264321
a chemotype that inhibits three unrelated pathogenic targets: the botulinum neurotoxin serotype a light chain, p. falciparum malaria, and the ebola filovirus.a 1,7-bis(alkylamino)diazachrysene-based small molecule was previously identified as an inhibitor of the botulinum neurotoxin serotype a light chain metalloprotease. subsequently, a variety of derivatives of this chemotype were synthesized to develop structure-activity relationships, and all are inhibitors of the bont/a lc. three-dimensional analyses indicated that half of the originally discovered 1,7-daac structure superimposed well with 4-amino-7-chloroquinoline-based antimalarial agents. thi ...201121265542
identification of a small-molecule entry inhibitor for filoviruses.ebola virus (ebov) causes severe hemorrhagic fever, for which therapeutic options are not available. preventing the entry of ebov into host cells is an attractive antiviral strategy, which has been validated for hiv by the fda approval of the anti-hiv drug enfuvirtide. to identify inhibitors of ebov entry, the ebov envelope glycoprotein (ebov-gp) gene was used to generate pseudotype viruses for screening of chemical libraries. a benzodiazepine derivative (compound 7) was identified from a high-t ...201121270170
interplay between hiv entry and transportin-sr2 dependency.transportin-sr2 (trn-sr2, tnpo3, transportin 3) was previously identified as an interaction partner of human immunodeficiency virus type 1 (hiv-1) integrase and functions as a nuclear import factor of hiv-1. a possible role of capsid in transportin-sr2-mediated nuclear import was recently suggested by the findings that a chimeric hiv virus, carrying the murine leukemia virus (mlv) capsid and matrix proteins, displayed a transportin-sr2 independent phenotype, and that the hiv-1 n74d capsid mutant ...201121276267
campylobacter troglodytis sp. nov., isolated from feces of human-habituated wild chimpanzees (pan troglodytes schweinfurthii) in tanzania.the transmission of simian immunodeficiency and ebola viruses to humans in recent years has heightened awareness of the public health significance of zoonotic diseases of primate origin, particularly from chimpanzees. in this study, we analyzed 71 fecal samples collected from 2 different wild chimpanzee (pan troglodytes) populations with different histories in relation to their proximity to humans. campylobacter spp. were detected by culture in 19/56 (34%) group 1 (human habituated for research ...201121278267
expression of an immunogenic ebola immune complex in nicotiana benthamiana.filoviruses (ebola and marburg viruses) cause severe and often fatal haemorrhagic fever in humans and non-human primates. the us centers for disease control identifies ebola and marburg viruses as 'category a' pathogens (defined as posing a risk to national security as bioterrorism agents), which has lead to a search for vaccines that could prevent the disease. because the use of such vaccines would be in the service of public health, the cost of production is an important component of their dev ...201121281425
high-dose mannose-binding lectin therapy for ebola virus infection.mannose-binding lectin (mbl) targets diverse microorganisms for phagocytosis and complement-mediated lysis by binding specific surface glycans. although recombinant human mbl (rhmbl) trials have focused on reconstitution therapy, safety studies have identified no barriers to its use at higher levels. ebola viruses cause fatal hemorrhagic fevers for which no treatment exists and that are feared as potential biothreat agents. we found that mice whose rhmbl serum concentrations were increased =7-fo ...201121288816
[the past decade's infectious diseases].the past decade saw emerging infections such as sars, avian and pandemic influenza, food-borne infections and the bioterror threat. new vaccines became available and novel technologies for detection and typing of microorganisms were applied. in the years to come, control of antimicrobial drug resistance and nosocomial infections will continue to pose challenges in the light of an increasing number of senior citizens and individuals with chronic diseases. there will also be unknown challenges: we ...201121299933
evidence for ebola virus superantigen activity. 201121307193
review: micronutrient selenium deficiency influences evolution of some viral infectious diseases.recently emerged viral infectious diseases (vids) include hiv/aids, influenzas h5n1 and 2009 h1n1, sars, and ebola hemorrhagic fevers. earlier research determined metabolic oxidative stress in hosts deficient in antioxidant selenium (se) (<1 µmol se/l of blood) induces both impaired human host immunocompetence and rapidly mutated benign variants of rna viruses to virulence. these viral mutations are consistent, rather than stochastic, and long-lived. when se-deficient virus-infected hosts were s ...201121318622
ebola virus glycoprotein fc fusion protein confers protection against lethal challenge in vaccinated mice.ebola virus is a filoviridae that causes hemorrhagic fever in humans and induces high morbidity and mortality rates. filoviruses are classified as "category a bioterrorism agents", and currently there are no licensed therapeutics or vaccines to treat and prevent infection. the filovirus glycoprotein (gp) is sufficient to protect individuals against infection, and several vaccines based on gp are under development including recombinant adenovirus, parainfluenza virus, venezuelan equine encephalit ...201121329775
tackling ebola: new insights into prophylactic and therapeutic intervention strategies.abstract: since its discovery in 1976, ebolavirus has caused periodic outbreaks of viral hemorrhagic fever associated with severe and often fatal disease. ebolavirus is endemic in central africa and the philippines. although there is currently no approved treatment available, the past 10 years has seen remarkable progress in our understanding of the pathogenicity of ebolavirus and the development of prophylactic and post-exposure therapies against it. in vitro and in vivo experiments have shown ...201121349211
geminiviral vectors based on bean yellow dwarf virus for production of vaccine antigens and monoclonal antibodies in plants.expression of recombinant vaccine antigens and monoclonal antibodies using plant viral vectors has developed extensively during the past several years. the approach benefits from high yields of recombinant protein obtained within days after transient delivery of viral vectors to leaves of nicotiana benthamiana, a tobacco relative. modified viral genomes of both rna and dna viruses have been created. geminiviruses such as bean yellow dwarf virus (beydv) have a small, single stranded dna genome th ...201121358270
involvement of viral envelope gp2 in ebola virus entry into cells expressing the macrophage galactose-type c-type lectin.ebola virus (ebov) infection is initiated by the interaction of the viral surface envelope glycoprotein (gp) with the binding sites on target cells. differences in the mortality among different species of the ebola viruses, i.e., zaire ebolavirus (zebov) and reston ebolavirus (rebov), correspond to the in vitro infectivity of the pseudo-typed virus constructed with the gps in cells expressing macrophage galactose-type calcium-type lectin (mgl/cd301). through mutagenesis of gp2, the transmembrane ...201121362405
[antigenic differences in wild-type and guinea pig-adapted ebola virus strains].the splenocytes isolated from the mice immunized with wild-type or guinea pig-adapted ebola virus strains were used to obtain hybridoma collections. investigation of the monoclonal antibodies (mab) obtained to one of the strains to another revealed antigenic interstrain differences in nucleoprotein and vp40. it is interesting that the differences were found in the hydridoma collection obtained against the wild-type strain. the mabs produced by hydridomas to the adapted strain were found to equal ...201021381339
a new ebola virus nonstructural glycoprotein expressed through rna editing.ebola virus (ebov), an enveloped, single-stranded, negative-sense rna virus, causes severe hemorrhagic fever in humans and nonhuman primates. the ebov glycoprotein (gp) gene encodes the nonstructural soluble glycoprotein (sgp) but also produces the transmembrane glycoprotein (gp1,2) through transcriptional editing. a third gp gene product, a small soluble glycoprotein (ssgp), has long been postulated to be produced also as a result of transcriptional editing. to identify and characterize the exp ...201121411529
trends of major disease outbreaks in the african region, 2003-2007.communicable disease outbreaks cause millions of deaths throughout sub-saharan africa each year. most of the diseases causing epidemics in the region have been nearly eradicated or brought under control in other parts of the world. in recent years, considerable effort has been directed toward public health initiatives and strategies with a potential for significant impact in the fight against infectious diseases. in 1998, the world health organization african regional office (who/afro) launched ...201021413568
lessons learned during active epidemiological surveillance of ebola and marburg viral hemorrhagic fever epidemics in africa.to review epidemiological surveillance approaches used during ebola and marburg hemorrhagic fever epidemics in africa in the past fifteen years. overall, 26 hemorrhagic epidemic outbreaks have been registered in 12 countries; 18 caused by the ebola virus and eight by the marburg virus. about 2551 cases have been reported, among which 268 were health workers (9,3%).201021413569
[study of the functional role of mutation in the guinea pig-adapted ebola virus genome on a drosophila melanogaster model].ebola virus virulence in guinea pigs, which appears through virus adaptation to this animal host, correlates with substitutions in the gene encoding vp24 protein. in particular, the substitution his-->tyr186 was found when obtaining strain 8 ms. an attempt was made to clarify the functional role of this substitution in a transgenic fruit fly model. using the drosophila transformation technique provided transgenic strains that contained genomic insertions of wild-type ebola virus vp24 gene and th ...201121427954
inhibition of ebola virus entry by a c-peptide targeted to endosomes.ebola virus (ebov) and marburg virus (marv) (filoviruses) are the causative agents of severe hemorrhagic fever. infection begins with uptake of particles into cellular endosomes, where the viral envelope glycoprotein (gp) catalyzes fusion between the viral and host cell membranes. this fusion event is thought to involve conformational rearrangements of the transmembrane subunit (gp2) of the envelope spike that ultimately result in formation of a six-helix bundle by the n- and c-terminal heptad r ...201121454542
laboratory detection and diagnosis of filoviruses.ebola virus (ebov) and marburg virus (marv), belonging to the filoviridae family, emerged four decades ago and caused severe viral hemorrhagic fever in human and other primates. as high as 50-90% mortality, filoviruses can cause significant threats to public health. however, so far no specific and efficient vaccine has been available, nor have other treatment methods proved to be effective. it is of great importance to detect these pathogens specific, rapidly and sensitively in order to control ...201121468930
development and characterization of rabbit and mouse antibodies against ebolavirus envelope glycoproteins.ebolaviruses are the etiologic agents of severe viral hemorrhagic fevers in primates, including humans, and could be misused for the development of biological weapons. the ability to rapidly detect and differentiate these viruses is therefore crucial. antibodies that can detect reliably the ebolavirus surface envelope glycoprotein gp(1,2) or a truncated variant that is secreted from infected cells (sgp) are required for advanced development of diagnostic assays such as sandwich elisas or western ...201121513741
european risk assessment guidance for infectious diseases transmitted on aircraft - the ragida project. 201121527131
from the cover: t-cell immunoglobulin and mucin domain 1 (tim-1) is a receptor for zaire ebolavirus and lake victoria marburgvirus.the glycoproteins (gp) of enveloped viruses facilitate entry into the host cell by interacting with specific cellular receptors. despite extensive study, a cellular receptor for the deadly filoviruses ebolavirus and marburgvirus has yet to be identified and characterized. here, we show that t-cell ig and mucin domain 1 (tim-1) binds to the receptor binding domain of the zaire ebola virus (ebov) glycoprotein, and ectopic tim-1 expression in poorly permissive cells enhances ebov infection by 10- t ...201121536871
detection of viruses in used ventilation filters from two large public buildings.background: viral and bacterial pathogens may be present in the air after being released from infected individuals and animals. filters are installed in the heating, ventilation, and air-conditioning (hvac) systems of buildings to protect ventilation equipment and maintain healthy indoor air quality. these filters process enormous volumes of air. this study was undertaken to determine the utility of sampling used ventilation filters to assess the types and concentrations of virus aerosols presen ...201121549446
ebola virus as a foodborne pathogen? cause for consideration, but not panic. 201121571727
replication, pathogenicity, shedding, and transmission of zaire ebolavirus in pigs.background. reston ebolavirus was recently detected in pigs in the philippines. specific antibodies were found in pig farmers, indicating exposure to the virus. this important observation raises the possibility that pigs may be susceptible to ebola virus infection, including from other species, such as zaire ebolavirus (zebov), and can transmit to other susceptible hosts. methods. this study investigated whether zebov, a species commonly reemerging in central africa, can replicate and induce dis ...201121571728
protocol for recombinant rbd-based sars vaccines: protein preparation, animal vaccination and neutralization detection.based on their safety profile and ability to induce potent immune responses against infections, subunit vaccines have been used as candidates for a wide variety of pathogens (1-3). since the mammalian cell system is capable of post-translational modification, thus forming properly folded and glycosylated proteins, recombinant proteins expressed in mammalian cells have shown the greatest potential to maintain high antigenicity and immunogenicity (4-6). although no new cases of sars have been repo ...201121587153
comparative virology and aids (review).the scientific debate between pros and cons of the hiv criminal theory of aids still remains unsettled. the purpose of this review is to promote resolution of the problem by extracting a common principle of the host-virus relation using data resources for each of 4 viruses as follows: a) polyoma virus, b) marek's disease virus, c) ebola virus, d) korean hemorrhagic fever virus. conclusions drawn from this study are given as follows: i) environment emerged as the cardinal factor to modify the pro ...199621594370
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