The Experts below are selected from a list of 105 Experts worldwide ranked by ideXlab platform
Jay W. Hooper - One of the best experts on this subject based on the ideXlab platform.
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An attenuated Machupo Virus with a disrupted L-segment intergenic region protects guinea pigs against lethal Guanarito Virus infection
Scientific Reports, 2017Co-Authors: Joseph W. Golden, Steven A. Kwilas, Brett Beitzel, Eric M Mucker, Jason T. Ladner, Gustavo Palacios, Jay W. HooperAbstract:Machupo Virus (MACV) is a New World (NW) arenaVirus and causative agent of Bolivian hemorrhagic fever (HF). Here, we identified a variant of MACV strain Carvallo termed Car^91 that was attenuated in guinea pigs. Infection of guinea pigs with an earlier passage of Carvallo, termed Car^68, resulted in a lethal disease with a 63% mortality rate. Sequencing analysis revealed that compared to Car^68, Car^91 had a 35 nucleotide (nt) deletion and a point mutation within the L-segment intergenic region (IGR), and three silent changes in the polymerase gene that did not impact amino acid coding. No changes were found on the S-segment. Because it was apathogenic, we determined if Car^91 could protect guinea pigs against Guanarito Virus (GTOV), a distantly related NW arenaVirus. While naïve animals succumbed to GTOV infection, 88% of the Car^91-exposed guinea pigs were protected. These findings indicate that attenuated MACV vaccines can provide heterologous protection against NW arenaViruses. The disruption in the L-segment IGR, including a single point mutant and 35 nt partial deletion, were the only major variance detected between virulent and avirulent isolates, implicating its role in attenuation. Overall, our data support the development of live-attenuated arenaViruses as broadly protective pan-arenaVirus vaccines.
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partial deletion of the l segment intergenic region produces an attenuated machupo Virus that protects guinea pigs against lethal Guanarito Virus infection
2017Co-Authors: Joseph W. Golden, Steven A. Kwilas, Brett Beitzel, Eric M Mucker, Gustavo Palacious, Jay W. HooperAbstract:Abstract : Machupo Virus strain Carvallo is historically lethal in guinea pigs. We identified a variant termed Car91 that failed to produce even mild disease in infected animals. Here, the nature of this attenuation was explored in detail. Car91 was serologically indistinguishable from a lower passage isolate termed Car68, however Car91 replicated less efficiently in three cell lines. Sequencing analysis revealed Car91 had a 35 nucleotide deletion in the L-segment non-coding intergenic region. Contrary to Car91, Car68 produced a lethal infection in guinea pigs with a mortality rate of 63 . The ability of non-virulent Car91 to protect guinea pigs against a related arenaVirus, Guanarito Virus, was investigated. All nave animals succumbed to infection, however; 88 of Car91-infected guinea pigs were protected. Our findings suggest that partial deletion of the arenaVirus IGR is a viable means of producing attenuated arenaViruses that can function as broad spectrum arenaVirus vaccines.
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Glycoprotein-Specific Antibodies Produced by DNA Vaccination Protect Guinea Pigs from Lethal Argentine and Venezuelan Hemorrhagic Fever
Journal of Virology, 2016Co-Authors: Joseph W. Golden, Piet Maes, Steven A. Kwilas, John Ballantyne, Jay W. HooperAbstract:UNLABELLED Several members of the Arenaviridae can cause acute febrile diseases in humans, often resulting in lethality. The use of convalescent-phase human plasma is an effective treatment in humans infected with arenaViruses, particularly species found in South America. Despite this, little work has focused on developing potent and defined immunotherapeutics against arenaViruses. In the present study, we produced arenaVirus neutralizing antibodies by DNA vaccination of rabbits with plasmids encoding the full-length glycoprotein precursors of Junin Virus (JUNV), Machupo Virus (MACV), and Guanarito Virus (GTOV). Geometric mean neutralizing antibody titers, as measured by the 50% plaque reduction neutralization test (PRNT(50)), exceeded 5,000 against homologous Viruses. Antisera against each targeted Virus exhibited limited cross-species binding and, to a lesser extent, cross-neutralization. Anti-JUNV glycoprotein rabbit antiserum protected Hartley guinea pigs from lethal intraperitoneal infection with JUNV strain Romero when the antiserum was administered 2 days after challenge and provided some protection (∼30%) when administered 4 days after challenge. Treatment starting on day 6 did not protect animals. We further formulated an IgG antibody cocktail by combining anti-JUNV, -MACV, and -GTOV antibodies produced in DNA-vaccinated rabbits. This cocktail protected 100% of guinea pigs against JUNV and GTOV lethal disease. We then expanded on this cocktail approach by simultaneously vaccinating rabbits with a combination of plasmids encoding glycoproteins from JUNV, MACV, GTOV, and Sabia Virus (SABV). Sera collected from rabbits vaccinated with the combination vaccine neutralized all four targets. These findings support the concept of using a DNA vaccine approach to generate a potent pan-arenaVirus immunotherapeutic. IMPORTANCE ArenaViruses are an important family of emerging Viruses. In infected humans, convalescent-phase plasma containing neutralizing antibodies can mitigate the severity of disease caused by arenaViruses, particularly species found in South America. Because of variations in potency of the human-derived product, limited availability, and safety concerns, this treatment option has essentially been abandoned. Accordingly, despite this approach being an effective postinfection treatment option, research on novel approaches to produce potent polyclonal antibody-based therapies have been deficient. Here we show that DNA-based vaccine technology can be used to make potently neutralizing antibodies in rabbits that exclusively target the glycoproteins of several human-pathogenic arenaViruses found in South America, including JUNV, MACV, GTOV, and SABV. These antibodies protected guinea pigs from lethal disease when given post-Virus challenge. We also generated a purified antibody cocktail with antibodies targeting three arenaViruses and demonstrated protective efficacy against all three targets. Our findings demonstrate that use of the DNA vaccine technology could be used to produce candidate antiarenaVirus neutralizing antibody-based products.
Thomas G. Ksiazek - One of the best experts on this subject based on the ideXlab platform.
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NATURAL RODENT HOST ASSOCIATIONS OF Guanarito AND PIRITAL VirusES (FAMILY ARENAVIRIDAE) IN CENTRAL VENEZUELA
2013Co-Authors: Charles F. Fulhorst, Michael D. Bowen, Rosa Alba Salas, Nuris De Manzione, Gloria Duno, Antonio Utrera, Thomas G. Ksiazek, Edith De Miller, Clovis VasquezAbstract:Abstract. The objective of this study was to elucidate the natural rodent host relationships of Guanarito and Pirital Viruses (family Arenaviridae) in the plains of central Venezuela. Ninety-two arenaVirus isolates from 607 animals, representing 10 different rodent species, were characterized to the level of serotype. The 92 isolates comprised 19 Guanarito Virus strains and 73 Pirital Virus strains. The 19 Guanarito Virus isolates were from Zygodontomys brevicauda; 72 (98.6%) of the 73 Pirital Virus isolates were from Sigmodon alstoni. These results indicate that the natural rodent associations of these 2 sympatric arenaViruses are highly specific and that Z. brevicauda and S. alstoni are the principal rodent hosts of Guanarito and Pirital Viruses, respectively. Guanarito (GTO) Virus (family Arenaviridae) is the etiologic agent of Venezuelan hemorrhagic fever (VHF), a rodent-borne zoonosis that is endemic in the plains of central Venezuela. 1,2 In the first large-scale study on the epidemiology of VHF, 3 31 arenaVirus isolates (all presumed to be strains of GTO Virus) were recovered from 206 wild rodents collected in 1992 from the Municipality of Guanarito, State of Portuguesa. The 31 Virus isolates included 19 from 3
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Guanarito Virus (Arenaviridae) isolates from endemic and outlying localities in Venezuela: sequence comparisons among and within strains isolated from Venezuelan hemorrhagic fever patients and rodents.
Virology, 2000Co-Authors: Scott C. Weaver, James N. Mills, Charles F. Fulhorst, Rosa Alba Salas, Nuris De Manzione, Gloria Duno, Antonio Utrera, Thomas G. Ksiazek, Duilia TovarAbstract:Abstract Despite intensive surveillance, Venezuelan hemorrhagic fever (VHF), caused by Guanarito (GTO) Virus, has been detected in only a small region of western Venezuela. To determine whether VHF is associated with a particular regional GTO Virus strain(s), 29 isolates from rodents and humans throughout the surrounding regions were analyzed by partial sequencing of the nucleocapsid protein gene. Phylogenetic trees delineated nine distinct GTO genotypes that differ by 4–17% in nucleotides and up to 9% in amino acid sequences; most appeared to be restricted to discrete geographic regions, although a few genotypes were isolated in several locations. Each genotype included at least one strain recovered from a rodent, but only two genotypes were isolated from VHF cases. The presence outside of the endemic/epidemic region of two genotypes isolated also from VHF cases suggests that human pathogenic Viruses occur outside of the endemic zone, but do not frequently infect people and/or cause apparent disease there. VHF does not appear to be associated with a GTO Virus genotype that is restricted to a certain rodent species. When quasispecies diversity was examined, rodent isolates had higher sequence variation than human isolates. One rodent isolate included a mixture of two phylogenetically distinct genotypes, suggesting a dual infection.
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Experimental Infection of the Cane Mouse Zygodontomys brevicauda (Family Muridae) with Guanarito Virus (Arenaviridae), the Etiologic Agent of Venezuelan Hemorrhagic Fever
The Journal of infectious diseases, 1999Co-Authors: Charles F. Fulhorst, Thomas G. KsiazekAbstract:Chronic infections in specific rodents appear to be crucial to the long-term persistence of arenaViruses in nature. The cane mouse, Zygodontomys brevicauda, is a natural host of Guanarito Virus (family Arenaviridae), the etiologic agent of Venezuelan hemorrhagic fever. The purpose of this study was to elucidate the natural history of Guanarito Virus infection in Z. brevicauda. Thirty-nine laboratory-reared cane mice each were inoculated subcutaneously with 3.0 log10 plaque-forming units of the Guanarito Virus prototype strain INH-95551. No lethality was associated with infection in any animal, regardless of age at inoculation. The 13 newborn, 14 weanling, and 8 of the 12 adult animals developed chronic viremic infections characterized by persistent shedding of infectious Virus in oropharyngeal secretions and urine. These findings indicate that Guanarito Virus infection in Z. brevicauda can be chronic and thus support the concept that this rodent species is the natural reservoir of Guanarito Virus.
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field studies on the epidemiology of venezuelan hemorrhagic fever implication of the cotton rat sigmodon alstoni as the probable rodent reservoir
American Journal of Tropical Medicine and Hygiene, 1993Co-Authors: Mark L Wilson, Nuris De Manzione, R. Salas, D Tovar, Thomas G. KsiazekAbstract:During February 1992, field studies on the epidemiology of Venezuelan hemorrhagic fever (VHF) were carried out in a rural area of Portuguesa State in central Venezuela. The objective of this work was to determine the prevalence of infection with Guanarito Virus, the etiologic agent of VHF, among wild rodents and humans living within an endemic focus of the disease. A total of 234 rodents, representing nine different species, were collected and their spleens were cultured for Virus. Thirty-one Guanarito Virus isolates were made from two rodent species: 19 from 40 Sigmodon alstoni and 12 from 106 Zygodontomys brevicauda. Guanarito Virus antibody rates among these two species were 5.1% and 15.0%, respectively. Nine of the 12 Z. brevicauda that yielded Virus from their spleens also had Guanarito Virus antibodies in their sera. In contrast, none of the 19 Guanarito Virus-positive S. alstoni had antibodies to the Virus. These data suggest that S. alstoni usually develops a persistent nonimmunizing infection with Guanarito Virus, while Z. brevicauda develops an immunizing infection. Based on knowledge of the behavior of other human pathogenic arenaViruses, these results imply that S. alstoni is the principal rodent reservoir of Guanarito Virus in nature. To determine the prevalence of Guanarito Virus infection among humans in the same region, 195 people living near one of the rodent collecting sites were bled and their sera were tested for antibodies to the Virus. Five individuals (2.6%) had Guanarito Virus antibodies; all were adults, and two had been diagnosed previously as having VHF.(ABSTRACT TRUNCATED AT 250 WORDS)
Joseph W. Golden - One of the best experts on this subject based on the ideXlab platform.
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An attenuated Machupo Virus with a disrupted L-segment intergenic region protects guinea pigs against lethal Guanarito Virus infection
Scientific Reports, 2017Co-Authors: Joseph W. Golden, Steven A. Kwilas, Brett Beitzel, Eric M Mucker, Jason T. Ladner, Gustavo Palacios, Jay W. HooperAbstract:Machupo Virus (MACV) is a New World (NW) arenaVirus and causative agent of Bolivian hemorrhagic fever (HF). Here, we identified a variant of MACV strain Carvallo termed Car^91 that was attenuated in guinea pigs. Infection of guinea pigs with an earlier passage of Carvallo, termed Car^68, resulted in a lethal disease with a 63% mortality rate. Sequencing analysis revealed that compared to Car^68, Car^91 had a 35 nucleotide (nt) deletion and a point mutation within the L-segment intergenic region (IGR), and three silent changes in the polymerase gene that did not impact amino acid coding. No changes were found on the S-segment. Because it was apathogenic, we determined if Car^91 could protect guinea pigs against Guanarito Virus (GTOV), a distantly related NW arenaVirus. While naïve animals succumbed to GTOV infection, 88% of the Car^91-exposed guinea pigs were protected. These findings indicate that attenuated MACV vaccines can provide heterologous protection against NW arenaViruses. The disruption in the L-segment IGR, including a single point mutant and 35 nt partial deletion, were the only major variance detected between virulent and avirulent isolates, implicating its role in attenuation. Overall, our data support the development of live-attenuated arenaViruses as broadly protective pan-arenaVirus vaccines.
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partial deletion of the l segment intergenic region produces an attenuated machupo Virus that protects guinea pigs against lethal Guanarito Virus infection
2017Co-Authors: Joseph W. Golden, Steven A. Kwilas, Brett Beitzel, Eric M Mucker, Gustavo Palacious, Jay W. HooperAbstract:Abstract : Machupo Virus strain Carvallo is historically lethal in guinea pigs. We identified a variant termed Car91 that failed to produce even mild disease in infected animals. Here, the nature of this attenuation was explored in detail. Car91 was serologically indistinguishable from a lower passage isolate termed Car68, however Car91 replicated less efficiently in three cell lines. Sequencing analysis revealed Car91 had a 35 nucleotide deletion in the L-segment non-coding intergenic region. Contrary to Car91, Car68 produced a lethal infection in guinea pigs with a mortality rate of 63 . The ability of non-virulent Car91 to protect guinea pigs against a related arenaVirus, Guanarito Virus, was investigated. All nave animals succumbed to infection, however; 88 of Car91-infected guinea pigs were protected. Our findings suggest that partial deletion of the arenaVirus IGR is a viable means of producing attenuated arenaViruses that can function as broad spectrum arenaVirus vaccines.
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Glycoprotein-Specific Antibodies Produced by DNA Vaccination Protect Guinea Pigs from Lethal Argentine and Venezuelan Hemorrhagic Fever
Journal of Virology, 2016Co-Authors: Joseph W. Golden, Piet Maes, Steven A. Kwilas, John Ballantyne, Jay W. HooperAbstract:UNLABELLED Several members of the Arenaviridae can cause acute febrile diseases in humans, often resulting in lethality. The use of convalescent-phase human plasma is an effective treatment in humans infected with arenaViruses, particularly species found in South America. Despite this, little work has focused on developing potent and defined immunotherapeutics against arenaViruses. In the present study, we produced arenaVirus neutralizing antibodies by DNA vaccination of rabbits with plasmids encoding the full-length glycoprotein precursors of Junin Virus (JUNV), Machupo Virus (MACV), and Guanarito Virus (GTOV). Geometric mean neutralizing antibody titers, as measured by the 50% plaque reduction neutralization test (PRNT(50)), exceeded 5,000 against homologous Viruses. Antisera against each targeted Virus exhibited limited cross-species binding and, to a lesser extent, cross-neutralization. Anti-JUNV glycoprotein rabbit antiserum protected Hartley guinea pigs from lethal intraperitoneal infection with JUNV strain Romero when the antiserum was administered 2 days after challenge and provided some protection (∼30%) when administered 4 days after challenge. Treatment starting on day 6 did not protect animals. We further formulated an IgG antibody cocktail by combining anti-JUNV, -MACV, and -GTOV antibodies produced in DNA-vaccinated rabbits. This cocktail protected 100% of guinea pigs against JUNV and GTOV lethal disease. We then expanded on this cocktail approach by simultaneously vaccinating rabbits with a combination of plasmids encoding glycoproteins from JUNV, MACV, GTOV, and Sabia Virus (SABV). Sera collected from rabbits vaccinated with the combination vaccine neutralized all four targets. These findings support the concept of using a DNA vaccine approach to generate a potent pan-arenaVirus immunotherapeutic. IMPORTANCE ArenaViruses are an important family of emerging Viruses. In infected humans, convalescent-phase plasma containing neutralizing antibodies can mitigate the severity of disease caused by arenaViruses, particularly species found in South America. Because of variations in potency of the human-derived product, limited availability, and safety concerns, this treatment option has essentially been abandoned. Accordingly, despite this approach being an effective postinfection treatment option, research on novel approaches to produce potent polyclonal antibody-based therapies have been deficient. Here we show that DNA-based vaccine technology can be used to make potently neutralizing antibodies in rabbits that exclusively target the glycoproteins of several human-pathogenic arenaViruses found in South America, including JUNV, MACV, GTOV, and SABV. These antibodies protected guinea pigs from lethal disease when given post-Virus challenge. We also generated a purified antibody cocktail with antibodies targeting three arenaViruses and demonstrated protective efficacy against all three targets. Our findings demonstrate that use of the DNA vaccine technology could be used to produce candidate antiarenaVirus neutralizing antibody-based products.
Charles F. Fulhorst - One of the best experts on this subject based on the ideXlab platform.
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NATURAL RODENT HOST ASSOCIATIONS OF Guanarito AND PIRITAL VirusES (FAMILY ARENAVIRIDAE) IN CENTRAL VENEZUELA
2013Co-Authors: Charles F. Fulhorst, Michael D. Bowen, Rosa Alba Salas, Nuris De Manzione, Gloria Duno, Antonio Utrera, Thomas G. Ksiazek, Edith De Miller, Clovis VasquezAbstract:Abstract. The objective of this study was to elucidate the natural rodent host relationships of Guanarito and Pirital Viruses (family Arenaviridae) in the plains of central Venezuela. Ninety-two arenaVirus isolates from 607 animals, representing 10 different rodent species, were characterized to the level of serotype. The 92 isolates comprised 19 Guanarito Virus strains and 73 Pirital Virus strains. The 19 Guanarito Virus isolates were from Zygodontomys brevicauda; 72 (98.6%) of the 73 Pirital Virus isolates were from Sigmodon alstoni. These results indicate that the natural rodent associations of these 2 sympatric arenaViruses are highly specific and that Z. brevicauda and S. alstoni are the principal rodent hosts of Guanarito and Pirital Viruses, respectively. Guanarito (GTO) Virus (family Arenaviridae) is the etiologic agent of Venezuelan hemorrhagic fever (VHF), a rodent-borne zoonosis that is endemic in the plains of central Venezuela. 1,2 In the first large-scale study on the epidemiology of VHF, 3 31 arenaVirus isolates (all presumed to be strains of GTO Virus) were recovered from 206 wild rodents collected in 1992 from the Municipality of Guanarito, State of Portuguesa. The 31 Virus isolates included 19 from 3
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Transmission of Guanarito and Pirital Viruses among Wild Rodents, Venezuela
2013Co-Authors: Mary L. Milazzo, Gloria Duno, Antonio Utrera, Maria N.b. Cajimat, Freddy Duno, Charles F. FulhorstAbstract:Samples from rodents captured on a farm in Venezuela in February 1997 were tested for arenaVirus, antibody against Guanarito Virus (GTOV), and antibody against Pirital Virus (PIRV). Thirty-one (48.4%) of 64 short-tailed cane mice (Zygodontomys brevicauda) were infected with GTOV, 1 Alston’s cotton rat (Sigmodon alstoni) was infected with GTOV, and 36 (64.3%) of 56 other Alston’s cotton rats were infected with PIRV. The results of analyses of fi eld and laboratory data suggested that horizontal transmission is the dominant mode of GTOV transmission in Z. brevicauda mice and that vertical transmission is an important mode of PIRV transmission in S. alstoni rats. The results also suggested that bodily secretions and excretions from most GTOV-infected short-tailed cane mice and most PIRVinfected Alston’s cotton rats may transmit the Viruses to humans. The Tacaribe serocomplex Viruses (family Arenaviridae, genus ArenaVirus) known to occur in Venezuela are Guanarito Virus (GTOV) and Pirital Virus (PIRV) (1,2). GTOV is the etiologic agent of Venezuelan hemorrhagic fever (VHF) (1). The human health significance of PIRV has not been rigorously investigated (3). Specific members of the rodent family Cricetidae (4) are the principal hosts of the Tacaribe complex Viruses for which natural host relationships have been well characterized. It is generally accepted that humans usually become infected with arenaViruses by inhalation of Virus i
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Guanarito Virus (Arenaviridae) isolates from endemic and outlying localities in Venezuela: sequence comparisons among and within strains isolated from Venezuelan hemorrhagic fever patients and rodents.
Virology, 2000Co-Authors: Scott C. Weaver, James N. Mills, Charles F. Fulhorst, Rosa Alba Salas, Nuris De Manzione, Gloria Duno, Antonio Utrera, Thomas G. Ksiazek, Duilia TovarAbstract:Abstract Despite intensive surveillance, Venezuelan hemorrhagic fever (VHF), caused by Guanarito (GTO) Virus, has been detected in only a small region of western Venezuela. To determine whether VHF is associated with a particular regional GTO Virus strain(s), 29 isolates from rodents and humans throughout the surrounding regions were analyzed by partial sequencing of the nucleocapsid protein gene. Phylogenetic trees delineated nine distinct GTO genotypes that differ by 4–17% in nucleotides and up to 9% in amino acid sequences; most appeared to be restricted to discrete geographic regions, although a few genotypes were isolated in several locations. Each genotype included at least one strain recovered from a rodent, but only two genotypes were isolated from VHF cases. The presence outside of the endemic/epidemic region of two genotypes isolated also from VHF cases suggests that human pathogenic Viruses occur outside of the endemic zone, but do not frequently infect people and/or cause apparent disease there. VHF does not appear to be associated with a GTO Virus genotype that is restricted to a certain rodent species. When quasispecies diversity was examined, rodent isolates had higher sequence variation than human isolates. One rodent isolate included a mixture of two phylogenetically distinct genotypes, suggesting a dual infection.
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Experimental Infection of the Cane Mouse Zygodontomys brevicauda (Family Muridae) with Guanarito Virus (Arenaviridae), the Etiologic Agent of Venezuelan Hemorrhagic Fever
The Journal of infectious diseases, 1999Co-Authors: Charles F. Fulhorst, Thomas G. KsiazekAbstract:Chronic infections in specific rodents appear to be crucial to the long-term persistence of arenaViruses in nature. The cane mouse, Zygodontomys brevicauda, is a natural host of Guanarito Virus (family Arenaviridae), the etiologic agent of Venezuelan hemorrhagic fever. The purpose of this study was to elucidate the natural history of Guanarito Virus infection in Z. brevicauda. Thirty-nine laboratory-reared cane mice each were inoculated subcutaneously with 3.0 log10 plaque-forming units of the Guanarito Virus prototype strain INH-95551. No lethality was associated with infection in any animal, regardless of age at inoculation. The 13 newborn, 14 weanling, and 8 of the 12 adult animals developed chronic viremic infections characterized by persistent shedding of infectious Virus in oropharyngeal secretions and urine. These findings indicate that Guanarito Virus infection in Z. brevicauda can be chronic and thus support the concept that this rodent species is the natural reservoir of Guanarito Virus.
Shigeru Morikawa - One of the best experts on this subject based on the ideXlab platform.
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Characterization of Monoclonal Antibodies to Junin Virus Nucleocapsid Protein and Application to the Diagnosis of Hemorrhagic Fever Caused by South American ArenaViruses
Clinical and Vaccine Immunology, 2009Co-Authors: Mina Nakauchi, Shuetsu Fukushi, Masayuki Saijo, Tetsuya Mizutani, Agustín E. Ure, Víctor Romanowski, Ichiro Kurane, Shigeru MorikawaAbstract:Junin Virus (JUNV), Machupo Virus, Guanarito Virus, Sabia Virus, and Chapare Virus are members of New World arenaVirus clade B and are the etiological agents of viral hemorrhagic fevers that occur in South America. In this study, we produced three monoclonal antibodies (MAbs) to the recombinant nucleocapsid protein of JUNV, designated C6-9, C11-12, and E4-2. The specificity of these MAbs was examined by enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescence assay, and an epitope-mapping method. Using these MAbs, we developed antigen (Ag) capture ELISA systems. We showed that by using MAb C6-9, JUNV Ag was specifically detected. On the other hand, by using MAb C11-12 or E-4-2, the Ags of all human pathogenic South American arenaViruses were detected. The combined use of these Ag capture ELISA systems in the present study may be useful for the diagnosis of acute-phase viral hemorrhagic fever due to infection by a South American arenaVirus.
