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Almajhdi FN, Farrag MA, Amer HM. Group B strains of human respiratory syncytial virus in Saudi Arabia: molecular and phylogenetic analysis. Virus Genes 2013; 48:252-9. [PMID: 24370974 DOI: 10.1007/s11262-013-1030-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Accepted: 12/19/2013] [Indexed: 11/28/2022]
Abstract
The genetic variability and circulation pattern of human respiratory syncytial virus group B (HRSV-B) strains, identified in Riyadh during the winters of 2008 and 2009, were evaluated by partial sequencing of the attachment (G) protein gene. The second hypervariable region (HVR-2) of G gene was amplified by RT-PCR, sequenced and compared to representatives of different HRSV-B genotypes. Sequence and phylogenetic analysis revealed that all Saudi strains belonged to the genotype BA, which is characterized by 60-nucleotide duplication at HVR-2. Only strains of 2008 were clustered with subgroup BA-IV, while those isolated at 2009 were clustered among the most recent subgroups (particularly BA-X and CB-B). Amino acid sequence analysis demonstrated 18 amino acid substitutions in Saudi HRSV-B strains; among which five are specific for individual strains. Furthermore, two potential N-glycosylation sites at residues 230 and 296 were identified for all Saudi strains, and an additional site at amino acid 273 was found only in Riyadh 28/2008 strain. O-glycosylation was predicted in 42-43 sites, where the majority (no = 38) are highly conserved among Saudi strains. The average ratio between non-synonymous and synonymous mutations (ω) implied stabilizing selection pressure on G protein, with evidences of positive selection on certain Saudi strains. This report provides preliminary data on the circulation pattern and molecular characteristics of HRSV-B strains circulating in Saudi Arabia.
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Affiliation(s)
- Fahad N Almajhdi
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia,
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202
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Van Braeckel-Budimir N, Haijema BJ, Leenhouts K. Bacterium-like particles for efficient immune stimulation of existing vaccines and new subunit vaccines in mucosal applications. Front Immunol 2013; 4:282. [PMID: 24062748 PMCID: PMC3775300 DOI: 10.3389/fimmu.2013.00282] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 08/31/2013] [Indexed: 12/14/2022] Open
Abstract
The successful development of a mucosal vaccine depends critically on the use of a safe and effective immunostimulant and/or carrier system. This review describes the effectiveness and mode of action of an immunostimulating particle, derived from bacteria, used in mucosal subunit vaccines. The non-living particles, designated bacterium-like particles are based on the food-grade bacterium Lactococcus lactis. The focus of the overview is on the development of intranasal BLP-based vaccines to prevent diseases caused by influenza and respiratory syncytial virus, and includes a selection of Phase I clinical data for the intranasal FluGEM vaccine.
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203
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The comparative genomics of human respiratory syncytial virus subgroups A and B: genetic variability and molecular evolutionary dynamics. J Virol 2013; 87:8213-26. [PMID: 23698290 DOI: 10.1128/jvi.03278-12] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Genomic variation and related evolutionary dynamics of human respiratory syncytial virus (RSV), a common causative agent of severe lower respiratory tract infections, may affect its transmission behavior. RSV evolutionary patterns are likely to be influenced by a precarious interplay between selection favoring variants with higher replicative fitness and variants that evade host immune responses. Studying RSV genetic variation can reveal both the genes and the individual codons within these genes that are most crucial for RSV survival. In this study, we conducted genetic diversity and evolutionary rate analyses on 36 RSV subgroup B (RSV-B) whole-genome sequences. The attachment protein, G, was the most variable protein; accordingly, the G gene had a higher substitution rate than other RSV-B genes. Overall, less genetic variability was found among the available RSV-B genome sequences than among RSV-A genome sequences in a comparable sample. The mean substitution rates of the two subgroups were, however, similar (for subgroup A, 6.47 × 10(-4) substitutions/site/year [95% credible interval {CI 95%}, 5.56 × 10(-4) to 7.38 × 10(-4)]; for subgroup B, 7.76 × 10(-4) substitutions/site/year [CI 95%, 6.89 × 10(-4) to 8.58 × 10(-4)]), with the time to their most recent common ancestors (TMRCAs) being much lower for RSV-B (19 years) than for RSV-A (46.8 years). The more recent RSV-B TMRCA is apparently the result of a genetic bottleneck that, over longer time scales, is still compatible with neutral population dynamics. Whereas the immunogenic G protein seems to require high substitution rates to ensure immune evasion, strong purifying selection in conserved proteins such as the fusion protein and nucleocapsid protein is likely essential to preserve RSV viability.
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204
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Abstract
Cancer patients are frequently immunosuppressed and at risk for a wide range of opportunistic and healthcare-associated infections. A good infection prevention program is extremely important to reduce risk of infection. This review focuses on infection prevention measures specific to patients, healthcare personnel, and visitors in the cancer center.
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Affiliation(s)
- Kerri A Thom
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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205
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Rivera-Toledo E, Gómez B. Respiratory syncytial virus persistence in macrophages alters the profile of cellular gene expression. Viruses 2013; 4:3270-80. [PMID: 23342359 PMCID: PMC3528265 DOI: 10.3390/v4123270] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Viruses can persistently infect differentiated cells through regulation of expression of both their own genes and those of the host cell, thereby evading detection by the host’s immune system and achieving residence in a non-lytic state. Models in vitro with cell lines are useful tools in understanding the mechanisms associated with the establishment of viral persistence. In particular, a model to study respiratory syncytial virus (RSV) persistence in a murine macrophage-like cell line has been established. Compared to non-infected macrophages, macrophages persistently infected with RSV show altered expression both of genes coding for cytokines and trans-membrane proteins associated with antigen uptake and of genes related to cell survival. The biological changes associated with altered gene expression in macrophages as a consequence of persistent RSV infection are summarized.
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Affiliation(s)
- Evelyn Rivera-Toledo
- Department of Microbiology and Parasitology, Faculty of Medicine, Universidad Nacional Autónoma de México, Circuito exterior s/n, Ciudad Universitaria, México D.F., C.P. 04510, Mexico.
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206
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Neonatal calf infection with respiratory syncytial virus: drawing parallels to the disease in human infants. Viruses 2013; 4:3731-53. [PMID: 23342375 PMCID: PMC3528288 DOI: 10.3390/v4123731] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Respiratory syncytial virus (RSV) is the most common viral cause of childhood acute lower respiratory tract infections. It is estimated that RSV infections result in more than 100,000 deaths annually worldwide. Bovine RSV is a cause of enzootic pneumonia in young dairy calves and summer pneumonia in nursing beef calves. Furthermore, bovine RSV plays a significant role in bovine respiratory disease complex, the most prevalent cause of morbidity and mortality among feedlot cattle. Infection of calves with bovine RSV shares features in common with RSV infection in children, such as an age-dependent susceptibility. In addition, comparable microscopic lesions consisting of bronchiolar neutrophilic infiltrates, epithelial cell necrosis, and syncytial cell formation are observed. Further, our studies have shown an upregulation of pro-inflammatory mediators in RSV-infected calves, including IL-12p40 and CXCL8 (IL-8). This finding is consistent with increased levels of IL-8 observed in children with RSV bronchiolitis. Since rodents lack IL-8, neonatal calves can be useful for studies of IL-8 regulation in response to RSV infection. We have recently found that vitamin D in milk replacer diets can be manipulated to produce calves differing in circulating 25-hydroxyvitamin D3. The results to date indicate that although the vitamin D intracrine pathway is activated during RSV infection, pro-inflammatory mediators frequently inhibited by the vitamin D intacrine pathway in vitro are, in fact, upregulated or unaffected in lungs of infected calves. This review will summarize available data that provide parallels between bovine RSV infection in neonatal calves and human RSV in infants.
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207
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STAT3-mediated IL-17 production by postseptic T cells exacerbates viral immunopathology of the lung. Shock 2013; 38:515-23. [PMID: 23042197 DOI: 10.1097/shk.0b013e31826f862c] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Survivors of severe sepsis exhibit increased morbidity and mortality in response to secondary infections. Although bacterial secondary infections have been widely studied, there remains a paucity of data concerning viral infections after sepsis. In an experimental mouse model of severe sepsis (cecal ligation and puncture [CLP]) followed by respiratory syncytial virus (RSV) infection, exacerbated immunopathology was observed in the lungs of CLP mice compared with RSV-infected sham surgery mice. This virus-associated immunopathology was evidenced by increased mucus production in the lungs of RSV-infected CLP mice and correlated with increased IL-17 production in the lungs. Respiratory syncytial virus-infected CLP mice exhibited increased levels of TH2 cytokines and reduced interferon γ in the lungs and lymph nodes compared with RSV-infected sham mice. In addition, CD4 T cells from CLP mice produced increased IL-17 in vitro irrespective of the presence of exogenous cytokines or blocking antibodies. This increased IL-17 production correlated with increased STAT3 transcription factor binding to the IL-17 promoter in CD4 T cells from CLP mice. Furthermore, in vivo neutralization of IL-17 before RSV infection led to a significant reduction in virus-induced mucus production and TH2 cytokines. Taken together, these data provide evidence that postseptic CD4 T cells are primed toward IL-17 production via increased STAT3-mediated gene transcription, which may contribute to the immunopathology of a secondary viral infection.
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208
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Zeitlin L, Bohorov O, Bohorova N, Hiatt A, Kim DH, Pauly MH, Velasco J, Whaley KJ, Barnard DL, Bates JT, Crowe JE, Piedra PA, Gilbert BE. Prophylactic and therapeutic testing of Nicotiana-derived RSV-neutralizing human monoclonal antibodies in the cotton rat model. MAbs 2013; 5:263-9. [PMID: 23396091 PMCID: PMC3893236 DOI: 10.4161/mabs.23281] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 12/10/2012] [Accepted: 12/14/2012] [Indexed: 01/27/2023] Open
Abstract
Severe lower respiratory tract infection in infants and small children is commonly caused by respiratory syncytial virus (RSV). Palivizumab (Synagis(®)), a humanized IgG1 monoclonal antibody (mAb) approved for RSV immunoprophylaxis in at-risk neonates, is highly effective, but pharmacoeconomic analyses suggest its use may not be cost-effective. Previously described potent RSV neutralizers (human Fab R19 and F2-5; human IgG RF-1 and RF-2) were produced in IgG format in a rapid and inexpensive Nicotiana-based manufacturing system for comparison with palivizumab. Both plant-derived (palivizumab-N) and commercial palivizumab, which is produced in a mouse myeloma cell line, showed protection in prophylactic (p < 0.001 for both mAbs) and therapeutic protocols (p < 0.001 and p < 0.05 respectively). The additional plant-derived human mAbs directed against alternative epitopes displayed neutralizing activity, but conferred less protection in vivo than palivizumab-N or palivizumab. Palivizumab remains one of the most efficacious RSV mAbs described to date. Production in plants may reduce manufacturing costs and improve the pharmacoeconomics of RSV immunoprophylaxis and therapy.
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MESH Headings
- Animals
- Antibodies, Monoclonal, Humanized/economics
- Antibodies, Monoclonal, Humanized/immunology
- Antibodies, Monoclonal, Humanized/therapeutic use
- Antibodies, Neutralizing/economics
- Antibodies, Neutralizing/immunology
- Antibodies, Neutralizing/therapeutic use
- Disease Models, Animal
- Humans
- Palivizumab
- Respiratory Syncytial Virus Infections/immunology
- Respiratory Syncytial Virus Infections/prevention & control
- Respiratory Syncytial Virus Infections/virology
- Respiratory Syncytial Virus, Human/immunology
- Sigmodontinae
- Nicotiana/immunology
- Treatment Outcome
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209
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Bennett AL, Smith DW, Cummins MJ, Jacoby PA, Cummins JM, Beilharz MW. Low-dose oral interferon alpha as prophylaxis against viral respiratory illness: a double-blind, parallel controlled trial during an influenza pandemic year. Influenza Other Respir Viruses 2013; 7:854-62. [PMID: 23398960 PMCID: PMC5781220 DOI: 10.1111/irv.12094] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2012] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND OBJECTIVE Interferon alpha (IFNα) is a known antiviral agent. A double-blind, placebo-controlled clinical trial was conducted investigating the use of low-dose oral interferon alpha for preventing acute viral respiratory illnesses. METHODS Two hundred healthy adults aged 18-75 years were enrolled and completed weekly health data questionnaires to monitor for symptoms and impact of respiratory illness. Serum samples were tested for antibodies against influenza and other common respiratory viruses. RESULTS Low-dose oral IFNα prophylaxis did not reduce the incidence or impact of acute respiratory illness (ARI) or the impact of illness on daily activities. Post hoc analysis of participant subgroups, however, identified significant reductions in the incidence of ARI reported by males, those aged 50 years or more and those who received the 2009 seasonal influenza vaccine. Interferon alpha prophylaxis had a significant impact on the reporting of moderate-to-severe feverishness by the study population. Seropositive participants in the IFN group were more likely to report asymptomatic or mild symptoms compared with those in the placebo group who were more likely to report stronger symptoms. CONCLUSIONS Low-dose oral IFNα prophylaxis was not effective in limiting the overall incidence of ARI in our study population. However, there was evidence that prophylaxis reduced the severity of symptoms and had a beneficial effect in some subpopulations, including those who received the 2009 seasonal trivalent influenza vaccination.
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Affiliation(s)
- Alayne L Bennett
- School of Pathology and Laboratory Medicine, University of Western Australia, Perth, WA, Australia
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210
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Genetic variability among complete human respiratory syncytial virus subgroup A genomes: bridging molecular evolutionary dynamics and epidemiology. PLoS One 2012; 7:e51439. [PMID: 23236501 PMCID: PMC3517519 DOI: 10.1371/journal.pone.0051439] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 10/31/2012] [Indexed: 01/10/2023] Open
Abstract
Human respiratory syncytial virus (RSV) is an important cause of severe lower respiratory tract infections in infants and the elderly. In the vast majority of cases, however, RSV infections run mild and symptoms resemble those of a common cold. The immunological, clinical, and epidemiological profile of severe RSV infections suggests a disease caused by a virus with typical seasonal transmission behavior, lacking clear-cut virulence factors, but instead causing disease by modifying the host’s immune response in a way that stimulates pathogenesis. Yet, the interplay between RSV-evoked immune responses and epidemic behavior, and how this affects the genomic evolutionary dynamics of the virus, remains poorly understood. Here, we present a comprehensive collection of 33 novel RSV subgroup A genomes from strains sampled over the last decade, and provide the first measurement of RSV-A genomic diversity through time in a phylodynamic framework. In addition, we map amino acid substitutions per protein to determine mutational hotspots in specific domains. Using Bayesian genealogical inference, we estimated the genomic evolutionary rate to be 6.47×10−4 (credible interval: 5.56×10−4, 7.38×10−4) substitutions/site/year, considerably slower than previous estimates based on G gene sequences only. The G gene is however marked by elevated substitution rates compared to other RSV genes, which can be attributed to relaxed selective constraints. In line with this, site-specific selection analyses identify the G gene as the major target of diversifying selection. Importantly, statistical analysis demonstrates that the immune driven positive selection does not leave a measurable imprint on the genome phylogeny, implying that RSV lineage replacement mainly follows nonselective epidemiological processes. The roughly 50 years of RSV-A genomic evolution are characterized by a constant population size through time and general co-circulation of lineages over many epidemic seasons – a conclusion that might be taken into account when developing future therapeutic and preventive strategies.
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211
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Xiang Z, Gonzalez R, Ren L, Xiao Y, Chen L, Zhang J, Wang W, Yang Q, Li J, Zhou H, Vernet G, Paranhos-Baccalà G, Wang Z, Wang J. Prevalence and clinical characteristics of human respiratory syncytial virus in Chinese adults with acute respiratory tract infection. J Med Virol 2012. [PMID: 23192884 PMCID: PMC7166604 DOI: 10.1002/jmv.23467] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Respiratory syncytial virus (RSV) is a leading cause of respiratory tract illnesses worldwide. Although the prevalence and clinical manifestations of the two subtypes, RSV-A and RSV-B, have been studied in some detail in infants and young children, they have not been determined in adults. To evaluate the prevalence of the RSV subtypes and disease severity between RSV-A and RSV-B infections in adults, nasal and throat swabs that were collected from patients ≥15 years old who sought medical care for acute respiratory infections at the Fever Clinic of the Peking Union Medical College Hospital in Beijing, China between May 2005 and April 2010. The samples were tested for RSV infection using PCR and sequencing analysis. RSV was detected in 95 (1%) of the adult patients, of whom 53 (55.8%) were positive for RSV-A and 42 (44.2%) for RSV-B. The incidence of RSV infections increased with age (χ(2) = 37.17, P = 1.66E-07). Demographic data and clinical manifestations of RSV-A were similar to those of RSV-B. Although RSV-A and RSV-B co-circulated during the 2005-2006 and 2008-2009 seasons, RSV-A was predominant in the 2006-2008 seasons, whereas RSV-B was predominant in the 2009-2010 season. Upper respiratory tract infections were diagnosed in most RSV-infected patients (n = 80, 84.2%), and three patients suffered from pulmonary infection. This is the first study to provide data on the prevalence and clinical manifestations of RSV subgroups among Chinese adults with fever and acute illness, over five successive epidemic seasons.
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Affiliation(s)
- Zichun Xiang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
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212
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Delgado-Ortega M, Marc D, Dupont J, Trapp S, Berri M, Meurens F. SOCS proteins in infectious diseases of mammals. Vet Immunol Immunopathol 2012; 151:1-19. [PMID: 23219158 PMCID: PMC7112700 DOI: 10.1016/j.vetimm.2012.11.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 10/31/2012] [Accepted: 11/13/2012] [Indexed: 12/17/2022]
Abstract
As for most biological processes, the immune response to microbial infections has to be tightly controlled to remain beneficial for the host. Inflammation is one of the major consequences of the host's immune response. For its orchestration, this process requires a fine-tuned interplay between interleukins, endothelial cells and various types of recruited immune cells. Suppressors of cytokine signalling (SOCS) proteins are crucially involved in the complex control of the inflammatory response through their actions on various signalling pathways including the JAK/STAT and NF-κB pathways. Due to their cytokine regulatory functions, they are frequent targets for exploitation by infectious agents trying to escape the host's immune response. This review article aims to summarize our current knowledge regarding SOCS family members in the different mammalian species studied so far, and to display their complex molecular interactions with microbial pathogens.
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Affiliation(s)
- Mario Delgado-Ortega
- Institut National de la Recherche Agronomique (INRA), UMR1282 Infectiologie et Santé Publique, F-37380 Nouzilly, France
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213
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Molecular characterization of a respiratory syncytial virus outbreak in a hematology unit in Heidelberg, Germany. J Clin Microbiol 2012; 51:155-62. [PMID: 23100345 DOI: 10.1128/jcm.02151-12] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In 2011 and 2012, a large outbreak of respiratory syncytial virus (RSV) infections affecting 57 laboratory-confirmed patients occurred in an adult hematology unit in Heidelberg, Germany. During the outbreak investigation, we performed molecular genotyping of RSV strains to differentiate between single versus multiple introductions of the virus into the unit. Furthermore, we assessed the time of viral shedding of consecutive samples from the patients in order to better understand the possible impact of prolonged shedding for outbreak control management. We used subtype-specific reverse transcription-PCR on nasopharyngeal and bronchoalveolar specimens for routine diagnostics and for measuring the viral shedding period. Samples of 47 RSV-infected patients involved in the outbreak were genotyped by sequence analysis and compared to samples from RSV-infected hospitalized children representing the timing of the annual RSV epidemic in the community. Molecular investigation of the virus strains from clinical samples revealed a unique cluster with identical nucleotide sequences of RSV type A (RSV A outbreak strain) for 41 patients, while 3 patients were infected with different RSV A (nonoutbreak) strains and three other patients with RSV type B. Outbreak strains were identified in samples from November 2011 until January 2012, while nonoutbreak strains were from samples coinciding with the community epidemic in February and March 2012. Median duration of viral shedding time was 24.5 days (range, 1 to 168 days) with no difference between outbreak and nonoutbreak strains (P = 0.45). Our investigation suggests a single introduction of the RSV A outbreak strain into the unit that spread among the immunocompromised patients. Prolonged viral shedding may have contributed to nosocomial transmission and should be taken into account in the infection control management of RSV outbreaks in settings with heavily immunosuppressed patients.
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214
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Diversity and adaptation of human respiratory syncytial virus genotypes circulating in two distinct communities: public hospital and day care center. Viruses 2012. [PMID: 23202489 PMCID: PMC3509657 DOI: 10.3390/v4112432] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
HRSV is one of the most important pathogens causing acute respiratory tract diseases as bronchiolitis and pneumonia among infants. HRSV was isolated from two distinct communities, a public day care center and a public hospital in São José do Rio Preto - SP, Brazil. We obtained partial sequences from G gene that were used on phylogenetic and selection pressure analysis. HRSV accounted for 29% of respiratory infections in hospitalized children and 7.7% in day care center children. On phylogenetic analysis of 60 HRSV strains, 48 (80%) clustered within or adjacent to the GA1 genotype; GA5, NA1, NA2, BA-IV and SAB1 were also observed. SJRP GA1 strains presented variations among deduced amino acids composition and lost the potential O-glycosilation site at amino acid position 295, nevertheless this resulted in an insertion of two potential O-glycosilation sites at positions 296 and 297. Furthermore, a potential O-glycosilation site insertion, at position 293, was only observed for hospital strains. Using SLAC and MEME methods, only amino acid 274 was identified to be under positive selection. This is the first report on HRSV circulation and genotypes classification derived from a day care center community in Brazil.
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215
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Agoti CN, Mwihuri AG, Sande CJ, Onyango CO, Medley GF, Cane PA, Nokes DJ. Genetic relatedness of infecting and reinfecting respiratory syncytial virus strains identified in a birth cohort from rural Kenya. J Infect Dis 2012; 206:1532-41. [PMID: 22966119 PMCID: PMC3475639 DOI: 10.1093/infdis/jis570] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Background. Respiratory syncytial virus (RSV) reinfects individuals repeatedly. The extent to which this is a consequence of RSV antigenic diversity is unclear. Methods. Six-hundred thirty-five children from rural Kenya were closely monitored for RSV infection from birth through 3 consecutive RSV epidemics. RSV infections were identified by immunofluorescence testing of nasal washing samples collected during acute respiratory illnesses, typed into group A and B, and sequenced in the attachment (G) protein. A positive sample separated from a previous positive by ≥14 days was defined as a reinfection a priori. Results. Phylogenetic analysis was undertaken for 325 (80%) of 409 identified infections, including 53 (64%) of 83 reinfections. Heterologous group reinfections were observed in 28 episodes, and homologous group reinfections were observed in 25 episodes; 10 involved homologous genotypes, 5 showed no amino acid changes, and 3 were separated by 21–24 days and were potentially persistent infections. The temporal distribution of genotypes among reinfections did not differ from that of single infections. Conclusions. The vast majority of infection and reinfection pairs differed by group, genotype, or G amino acid sequence (ie, comprised distinct viruses). The extent to which this is a consequence of immune memory of infection history or prevalent diversity remains unclear.
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Affiliation(s)
- Charles N Agoti
- Kenya Medical Research Institute, Centre for Geographic Medicine Research, Coast, Kenya.
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216
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Long-term and memory immune responses in mice against Newcastle disease virus-like particles containing respiratory syncytial virus glycoprotein ectodomains. J Virol 2012; 86:11654-62. [PMID: 22896618 DOI: 10.1128/jvi.01510-12] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although respiratory syncytial virus (RSV) is a significant human pathogen, no RSV vaccines are available. We have reported that a virus-like particle (VLP) RSV vaccine candidate stimulated, in mice, robust, protective anti-RSV glycoprotein T(H)1 biased immune responses without enhanced respiratory disease upon RSV challenge. We report here an analysis of long-term responses to these VLPs. BALB/c mice immunized, without adjuvant, with VLPs or with infectious RSV generated anti-F and anti-G protein serum antibody responses that were stable over 14 months. Neutralizing antibody titers stimulated by VLPs were robust and durable for 14 months, whereas those of RSV-immunized animals declined significantly by 3 months. F protein-specific antibody-secreting cells were detected in the bone marrows of VLP-immunized mice but not in the marrows of RSV-immunized mice. Adoptive transfer of enriched splenic B cells from VLP-immunized mice into immunodeficient rag(-/-) mice resulted in anti-F and anti-G protein serum IgG antibody responses, in recipient mice, that were protective upon RSV challenge. In contrast, transfer of splenic B cells from RSV-immunized mice produced no detectable serum antibody in the recipients, nor could these mice inhibit RSV replication upon virus challenge. Immunization with VLPs stimulated the formation of germinal center GL7(+) B cells in normal mice. VLP immunization of TCR βδ(-/-) T-cell-deficient mice did not induce anti-RSV IgG antibodies, results consistent with T-cell-dependent immune responses. These results demonstrate that VLPs are effective in stimulating long-lived RSV-specific, T-cell-dependent neutralizing antibody-secreting cells and RSV-specific memory responses.
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217
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Haas LEM, de Rijk NX, Thijsen SFT. Human metapneumovirus infections on the ICU: a report of three cases. Ann Intensive Care 2012; 2:30. [PMID: 22812412 PMCID: PMC3519638 DOI: 10.1186/2110-5820-2-30] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Accepted: 04/30/2012] [Indexed: 11/23/2022] Open
Abstract
Although human metapneumovirus (hMPV) is primarily known as a causative agent of respiratory tract infections in children, the virus also can cause respiratory infections in adults. hMPV infections tend to be mild and are self-limiting, but the infections can be severe in the elderly and immunocompromised patients. Because hMPV infection is quite common, it should be considered in every patient with respiratory failure in the intensive care unit (ICU). We describe three adult patients, including a young pregnant woman, with hMPV infection who required admission to our ICU. Two of them developed respiratory failure with indication for mechanical ventilation.
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Affiliation(s)
- Lenneke E M Haas
- Department of Intensive Care Medicine, Diakonessenhuis, Utrecht, The Netherlands.
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218
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Widmer K, Zhu Y, Williams JV, Griffin MR, Edwards KM, Talbot HK. Rates of hospitalizations for respiratory syncytial virus, human metapneumovirus, and influenza virus in older adults. J Infect Dis 2012; 206:56-62. [PMID: 22529314 PMCID: PMC3415933 DOI: 10.1093/infdis/jis309] [Citation(s) in RCA: 221] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 01/13/2012] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND We performed a prospective study to determine the disease burden of respiratory syncytial virus (RSV) and human metapneumovirus (HMPV) in older adults in comparison with influenza virus. METHODS During 3 consecutive winters, we enrolled Davidson County (Nashville, TN) residents aged ≥ 50 years admitted to 1 of 4 hospitals with acute respiratory illness (ARI). Nasal/throat swabs were tested for influenza, RSV, and HMPV with reverse-transcriptase polymerase chain reaction. Hospitalization rates were calculated. RESULTS Of 1042 eligible patients, 508 consented to testing. Respiratory syncytial virus was detected in 31 participants (6.1%); HMPV was detected in 23 (4.5%) patients; and influenza was detected in 33 (6.5%) patients. Of those subjects aged ≥ 65 years, 78% received influenza vaccination. Compared with patients with confirmed influenza, patients with RSV were older and more immunocompromised; patients with HMPV were older, had more cardiovascular disease, were more likely to have received the influenza vaccination, and were less likely to report fever than those with influenza. Over 3 years, average annual rates of hospitalization were 15.01, 9.82, and 11.81 per 10,000 county residents due to RSV, HMPV, and influenza, respectively. CONCLUSIONS In adults aged ≥ 50 years, hospitalization rates for RSV and HMPV were similar to those associated with influenza.
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Affiliation(s)
| | | | - John V. Williams
- Department of Pediatrics
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center
| | - Marie R. Griffin
- Department of Medicine
- Department of Preventive Medicine
- Mid-South Geriatric Research Education and Clinical Center and Clinical Research Center of Excellence, VA TN Valley Health Care System, Nashville, Tennessee
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219
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McCarthy MK, Weinberg JB. Eicosanoids and respiratory viral infection: coordinators of inflammation and potential therapeutic targets. Mediators Inflamm 2012; 2012:236345. [PMID: 22665949 PMCID: PMC3362132 DOI: 10.1155/2012/236345] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Accepted: 03/12/2012] [Indexed: 12/20/2022] Open
Abstract
Viruses are frequent causes of respiratory infection, and viral respiratory infections are significant causes of hospitalization, morbidity, and sometimes mortality in a variety of patient populations. Lung inflammation induced by infection with common respiratory pathogens such as influenza and respiratory syncytial virus is accompanied by increased lung production of prostaglandins and leukotrienes, lipid mediators with a wide range of effects on host immune function. Deficiency or pharmacologic inhibition of prostaglandin and leukotriene production often results in a dampened inflammatory response to acute infection with a respiratory virus. These mediators may, therefore, serve as appealing therapeutic targets for disease caused by respiratory viral infection.
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Affiliation(s)
- Mary K. McCarthy
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Jason B. Weinberg
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI 48109, USA
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220
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Brock LG, Karron RA, Krempl CD, Collins PL, Buchholz UJ. Evaluation of pneumonia virus of mice as a possible human pathogen. J Virol 2012; 86:5829-43. [PMID: 22438539 PMCID: PMC3347304 DOI: 10.1128/jvi.00163-12] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Accepted: 03/08/2012] [Indexed: 01/22/2023] Open
Abstract
Pneumonia virus of mice (PVM), a relative of human respiratory syncytial virus (RSV), causes respiratory disease in mice. There is serologic evidence suggesting widespread exposure of humans to PVM. To investigate replication in primates, African green monkeys (AGM) and rhesus macaques (n = 4) were inoculated with PVM by the respiratory route. Virus was shed intermittently at low levels by a subset of animals, suggesting poor permissiveness. PVM efficiently replicated in cultured human cells and inhibited the type I interferon (IFN) response in these cells. This suggests that poor replication in nonhuman primates was not due to a general nonpermissiveness of primate cells or poor control of the IFN response. Seroprevalence in humans was examined by screening sera from 30 adults and 17 young children for PVM-neutralizing activity. Sera from a single child (6%) and 40% of adults had low neutralizing activity against PVM, which could be consistent with increasing incidence of exposure following early childhood. There was no cross-reaction of human or AGM sera between RSV and PVM and no cross-protection in the mouse model. In native Western blots, human sera reacted with RSV but not PVM proteins under conditions in which AGM immune sera reacted strongly. Serum reactivity was further evaluated by flow cytometry using unfixed Vero cells infected with PVM or RSV expressing green fluorescent protein (GFP) as a measure of viral gene expression. The reactivity of human sera against RSV-infected cells correlated with GFP expression, whereas reactivity against PVM-infected cells was low and uncorrelated with GFP expression. Thus, PVM specificity was not evident. Our results indicate that the PVM-neutralizing activity of human sera is not due to RSV- or PVM-specific antibodies but may be due to low-affinity, polyreactive natural antibodies of the IgG subclass. The absence of PVM-specific antibodies and restriction in nonhuman primates makes PVM unlikely to be a human pathogen.
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Affiliation(s)
- Linda G. Brock
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Ruth A. Karron
- Center for Immunization Research, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Christine D. Krempl
- Institute of Virology and Immunobiology, Julius-Maximilian University, Würzburg, Germany
| | - Peter L. Collins
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Ursula J. Buchholz
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
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221
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Kim S, Chang J. Baculovirus-based Vaccine Displaying Respiratory Syncytial Virus Glycoprotein Induces Protective Immunity against RSV Infection without Vaccine-Enhanced Disease. Immune Netw 2012; 12:8-17. [PMID: 22536165 PMCID: PMC3329602 DOI: 10.4110/in.2012.12.1.8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Revised: 01/08/2012] [Accepted: 01/08/2012] [Indexed: 02/03/2023] Open
Abstract
Background Respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract diseases in infancy and early childhood. Despite its importance as a pathogen, there is no licensed vaccine against RSV yet. The attachment glycoprotein (G) of RSV is a potentially important target for protective antiviral immune responses. Recombinant baculovirus has been recently emerged as a new vaccine vector, since it has intrinsic immunostimulatory properties and good bio-safety profile. Methods We have constructed a recombinant baculovirus-based RSV vaccine, Bac-RSV/G, displaying G glycoprotein, and evaluated immunogenicity and protective efficacy by intranasal immunization of BALB/c mice with Bac-RSV/G. Results Bac-RSV/G efficiently provides protective immunity against RSV challenge. Strong serum IgG and mucosal IgA responses were induced by intranasal immunization with Bac-RSV/G. In addition to humoral immunity, G-specific Th17- as well as Th1-type T-cell responses were detected in the lungs of Bac-RSV/G-immune mice upon RSV challenge. Neither lung eosinophilia nor vaccine-induced weight loss was observed upon Bac-RSV/G immunization and subsequent RSV infection. Conclusion Our data demonstrate that intranasal administration of baculovirus-based Bac-RSV/G vaccine is efficient for the induction of protection against RSV and represents a promising prophylactic vaccination regimen.
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Affiliation(s)
- Sol Kim
- Division of Life & Pharmaceutical Sciences, and Center for Cell Signaling & Drug Discovery Research, Ewha Womans University, Seoul 120-750, Korea
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222
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Abstract
Viruses cause a high percentage of community-acquired pneumonias. The advent of polymerase chain reaction and other molecular techniques has been associated with the detection of a higher prevalence of common respiratory viruses than previously suspected. Better diagnostics have shown new viral pathogens regularly in epidemics, immunocompromised patients, and occasionally children. Despite better diagnostics, treatment for all but influenza is still very limited.
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MESH Headings
- Adenovirus Infections, Human/diagnosis
- Adenovirus Infections, Human/drug therapy
- Adenovirus Infections, Human/epidemiology
- Common Cold/therapy
- Cytomegalovirus Infections/diagnosis
- Cytomegalovirus Infections/drug therapy
- Herpesvirus 3, Human
- Humans
- Influenza A Virus, H1N1 Subtype
- Influenza, Human/diagnosis
- Influenza, Human/drug therapy
- Influenza, Human/epidemiology
- Paramyxoviridae Infections/diagnosis
- Paramyxoviridae Infections/drug therapy
- Paramyxoviridae Infections/epidemiology
- Pneumonia, Viral/diagnosis
- Pneumonia, Viral/drug therapy
- Pneumonia, Viral/virology
- Severe Acute Respiratory Syndrome/diagnosis
- Severe Acute Respiratory Syndrome/drug therapy
- Severe Acute Respiratory Syndrome/epidemiology
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Affiliation(s)
- Kathryn A Radigan
- Division of Pulmonary and Critical Care Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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223
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Sánchez-Yebra W, Ávila-Carrillo JA, Giménez-Sánchez F, Reyes-Bertos A, Sánchez-Forte M, Morales-Torres M, Rojas A, Mendoza J. Viral agents causing lower respiratory tract infections in hospitalized children: evaluation of the Speed-Oligo® RSV assay for the detection of respiratory syncytial virus. Eur J Clin Microbiol Infect Dis 2011; 31:243-50. [PMID: 21647616 PMCID: PMC7088155 DOI: 10.1007/s10096-011-1300-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Accepted: 05/15/2011] [Indexed: 11/01/2022]
Abstract
Respiratory syncytial virus (RSV) is the viral agent which is more frequently involved in lower respiratory tract infections (LRTIs) in infants under 1 year of age in developed countries. A new oligochromatographic assay, Speed-Oligo® RSV, was designed and optimized for the specific detection and identification of RSV subtypes A and B. The test was evaluated in 289 clinical samples from 169 hospitalized children using an immunochromatography (IC) test, virus isolation by culture, and an in-house real-time polymerase chain reaction (RT-PCR). Other viruses causing LRTIs were investigated by cell culture or PCR-based tests. Sixty-two patients were infected by RSV (36.7%). In addition, adenovirus, influenza B, parainfluenza 2, and human metapneumovirus were detected in rates ranging from 5 to 8%. A proportion of 10.1% of the patients had mixed infections. The sensitivity, specificity, and positive and negative predictive values were, respectively, 94.9, 99.4, 98.9, and 97.4% for Speed-Oligo® RSV, 92.9, 96.3, 92.9, and 96.3% for RT-PCR/RSV, and 58.4, 98.1, 93.3, and 82.6% for IC. Our rates of viral detection and co-infection were similar to those of previously reported series. Finally, we find that Speed-Oligo® RSV is a rapid and easy-to-perform technique for the detection of RSV and the identification of subtypes A and B.
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Affiliation(s)
- W Sánchez-Yebra
- Department of Microbiology, CH Torrecárdenas, 04009, Almería, Spain.
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De Clercq E. The next ten stories on antiviral drug discovery (part E): advents, advances, and adventures. Med Res Rev 2011; 31:118-60. [PMID: 19844936 PMCID: PMC7168424 DOI: 10.1002/med.20179] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This review article presents the fifth part (part E) in the series of stories on antiviral drug discovery. The ten stories belonging to this fifth part are dealing with (i) aurintricarboxylic acid; (ii) alkenyldiarylmethanes; (iii) human immunodeficiency virus (HIV) integrase inhibitors; (iv) lens epithelium‐derived growth factor as a potential target for HIV proviral DNA integration; (v) the status presens of neuraminidase inhibitors NAIs in the control of influenza virus infections; (vi) the status presens on respiratory syncytial virus inhibitors; (vii) tricyclic (1,N‐2‐ethenoguanine)‐based acyclovir and ganciclovir derivatives; (viii) glycopeptide antibiotics as antivirals targeted at viral entry; (ix) the potential (off‐label) use of cidofovir in the treatment of polyoma (JC and BK) virus infections; and (x) finally, thymidine phosphorylase as a target for both antiviral and anticancer agents. © 2009 Wiley Periodicals, Inc. Med Res Rev, 31, No. 1, 118–160, 2010
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Affiliation(s)
- Erik De Clercq
- Rega Institute for Medical Research, K.U.Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium.
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225
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Wright M, Piedimonte G. Respiratory syncytial virus prevention and therapy: past, present, and future. Pediatr Pulmonol 2011; 46:324-47. [PMID: 21438168 DOI: 10.1002/ppul.21377] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Revised: 08/24/2010] [Accepted: 08/29/2010] [Indexed: 11/06/2022]
Abstract
Respiratory syncytial virus (RSV) is the most common respiratory pathogen in infants and young children worldwide. More than 50 years after its discovery, and despite relentless attempts to identify pharmacological therapies to improve the clinical course and outcomes of this disease, the most effective therapy remains supportive care. Although the quest for a safe and effective vaccine remains unsuccessful, pediatricians practicing during the past decade have been able to protect at least the more vulnerable patients with safe and effective passive prophylaxis. This review summarizes the history, microbiology, epidemiology, pathophysiology, and clinical manifestations of this infection in order to provide the reader with the background information necessary to fully appreciate the many challenges presented by the clinical management of young children with bronchiolitis. The last part of this article attempts an evidence-based review of the pharmacologic strategies currently available and those being evaluated, intentionally omitting highly experimental approaches not yet tested in clinical trials and, therefore, not likely to become available in the foreseeable future.
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Affiliation(s)
- Melvin Wright
- Department of Pediatrics and Pediatric Research Institute, West Virginia University School of Medicine, Morgantown, West Virginia 26506-9214, USA
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226
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Yezli S, Otter JA. Minimum Infective Dose of the Major Human Respiratory and Enteric Viruses Transmitted Through Food and the Environment. FOOD AND ENVIRONMENTAL VIROLOGY 2011; 3:1-30. [PMID: 35255645 PMCID: PMC7090536 DOI: 10.1007/s12560-011-9056-7] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Accepted: 02/26/2011] [Indexed: 05/18/2023]
Abstract
Viruses are a significant cause of morbidity and mortality around the world. Determining the minimum dose of virus particles that can initiate infection, termed the minimum infective dose (MID), is important for the development of risk assessment models in the fields of food and water treatment and the implementation of appropriate infection control strategies in healthcare settings. Both respiratory and enteric viruses can be shed at high titers from infected individuals even when the infection is asymptomatic. Presence of pre-existing antibodies has been shown to affect the infectious dose and to be protective against reinfection for many, but not all viruses. Most respiratory viruses appear to be as infective in humans as in tissue culture. Doses of <1 TCID50 of influenza virus, rhinovirus, and adenovirus were reported to infect 50% of the tested population. Similarly, low doses of the enteric viruses, norovirus, rotavirus, echovirus, poliovirus, and hepatitis A virus, caused infection in at least some of the volunteers tested. A number of factors may influence viruses' infectivity in experimentally infected human volunteers. These include host and pathogen factors as well as the experimental methodology. As a result, the reported infective doses of human viruses have to be interpreted with caution.
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Affiliation(s)
- Saber Yezli
- Bioquell UK Ltd, 52 Royce Close, West Portway, Andover, Hampshire, SP10 3TS, UK.
| | - Jonathan A Otter
- Bioquell UK Ltd, 52 Royce Close, West Portway, Andover, Hampshire, SP10 3TS, UK
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227
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Whaley KJ, Hiatt A, Zeitlin L. Emerging antibody products and Nicotiana manufacturing. HUMAN VACCINES 2011; 7:349-56. [PMID: 21358287 PMCID: PMC3166493 DOI: 10.4161/hv.7.3.14266] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Accepted: 11/21/2010] [Indexed: 12/19/2022]
Abstract
Antibody based products are not widely available to address multiple global health challenges due to high costs, limited manufacturing capacity, and long manufacturing lead times. Nicotiana-based manufacturing of antibody products may now begin to address these challenges as a result of revolutionary advances in transient expression and altered glycosylation pathways. This review provides examples of emerging antibody-based products (mucosal and systemic) that could be competitive and commercially viable when the attributes of Nicotiana-based manufacturing (large scale, versatile, rapid, low cost) are utilized.
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228
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Billam P, Bonaparte KL, Liu J, Ruckwardt TJ, Chen M, Ryder AB, Wang R, Dash P, Thomas PG, Graham BS. T Cell receptor clonotype influences epitope hierarchy in the CD8+ T cell response to respiratory syncytial virus infection. J Biol Chem 2011; 286:4829-41. [PMID: 21118816 PMCID: PMC3039322 DOI: 10.1074/jbc.m110.191437] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 11/27/2010] [Indexed: 01/19/2023] Open
Abstract
CD8+ T cell responses are important for recognizing and resolving viral infections. To better understand the selection and hierarchy of virus-specific T cell responses, we compared the T cell receptor (TCR) clonotype in parent and hybrid strains of respiratory syncytial virus-infected mice. K(d)M2(82-90) (SYIGSINNI) in BALB/c and D(b)M(187-195) (NAITNAKII) in C57Bl/6 are both dominant epitopes in parent strains but assume a distinct hierarchy, with K(d)M2(82-90) dominant to D(b)M(187-195) in hybrid CB6F1/J mice. The dominant K(d)M2(82-90) response is relatively public and is restricted primarily to the highly prevalent Vβ13.2 in BALB/c and hybrid mice, whereas D(b)M(187-195) responses in C57BL/6 mice are relatively private and involve multiple Vβ subtypes, some of which are lost in hybrids. A significant frequency of TCR CDR3 sequences in the D(b)M(187-195) response have a distinct "(D/E)WG" motif formed by a limited number of recombination strategies. Modeling of the dominant epitope suggested a flat, featureless structure, but D(b)M(187-195) showed a distinctive structure formed by Lys(7). The data suggest that common recombination events in prevalent Vβ genes may provide a numerical advantage in the T cell response and that distinct epitope structures may impose more limited options for successful TCR selection. Defining how epitope structure is interpreted to inform T cell function will improve the design of future gene-based vaccines.
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MESH Headings
- Amino Acid Motifs
- Animals
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- Chimera/genetics
- Chimera/immunology
- Chimera/metabolism
- Complementarity Determining Regions/genetics
- Complementarity Determining Regions/immunology
- Complementarity Determining Regions/metabolism
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/metabolism
- Mice
- Mice, Inbred BALB C
- Models, Immunological
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Respiratory Syncytial Virus Infections/genetics
- Respiratory Syncytial Virus Infections/immunology
- Respiratory Syncytial Virus Infections/metabolism
- Respiratory Syncytial Viruses/genetics
- Respiratory Syncytial Viruses/immunology
- Respiratory Syncytial Viruses/metabolism
- Species Specificity
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Affiliation(s)
- Padma Billam
- From the Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892-3017
| | - Kathryn L. Bonaparte
- From the Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892-3017
| | - Jie Liu
- From the Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892-3017
| | - Tracy J. Ruckwardt
- From the Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892-3017
| | - Man Chen
- From the Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892-3017
| | - Alex B. Ryder
- From the Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892-3017
| | - Rui Wang
- the Molecular Biology Section, Laboratory of Immunology, NIAID, National Institutes of Health, Bethesda, Maryland 20892-1892, and
| | - Pradyot Dash
- the Department of Immunology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | - Paul G. Thomas
- the Department of Immunology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | - Barney S. Graham
- From the Vaccine Research Center, NIAID, National Institutes of Health, Bethesda, Maryland 20892-3017
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229
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Graham BS. Biological challenges and technological opportunities for respiratory syncytial virus vaccine development. Immunol Rev 2011; 239:149-66. [PMID: 21198670 PMCID: PMC3023887 DOI: 10.1111/j.1600-065x.2010.00972.x] [Citation(s) in RCA: 177] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Respiratory syncytial virus (RSV) is an important cause of respiratory disease causing high rates of hospitalizations in infants, significant morbidity in children and adults, and excess mortality in the elderly. Major barriers to vaccine development include early age of RSV infection, capacity of RSV to evade innate immunity, failure of RSV-induced adaptive immunity to prevent reinfection, history of RSV vaccine-enhanced disease, and lack of an animal model fully permissive to human RSV infection. These biological challenges, safety concerns, and practical issues have significantly prolonged the RSV vaccine development process. One great advantage compared to other difficult viral vaccine targets is that passively administered neutralizing monoclonal antibody is known to protect infants from severe RSV disease. Therefore, the immunological goals for vaccine development are to induce effective neutralizing antibody to prevent infection and to avoid inducing T-cell response patterns associated with enhanced disease. Live-attenuated RSV and replication-competent chimeric viruses are in advanced clinical trials. Gene-based strategies, which can control the specificity and phenotypic properties of RSV-specific T-cell responses utilizing replication-defective vectors and which may improve on immunity from natural infection, are progressing through preclinical testing. Atomic level structural information on RSV envelope glycoproteins in complex with neutralizing antibodies is guiding design of new vaccine antigens that may be able to elicit RSV-specific antibody responses without induction of RSV-specific T-cell responses. These new technologies may allow development of vaccines that can protect against RSV-mediated disease in infants and establish a new immunological paradigm in the host to achieve more durable protection against reinfection.
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Affiliation(s)
- Barney S Graham
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-3017, USA.
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230
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Common Viral Pneumonia. PULMONARY INVOLVEMENT IN PATIENTS WITH HEMATOLOGICAL MALIGNANCIES 2011. [PMCID: PMC7115022 DOI: 10.1007/978-3-642-15742-4_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Common respiratory viruses are now recognised as true opportunistic respiratory pathogens in patients with haematological malignancies. The epidemiology of these viruses has not been extensively studied in immunocompromised hosts, but is probably closely related to viral activity in immunocompetent hosts, who constitute the virus reservoir for immunocompromised patients. In these patients, common respiratory viruses may cause severe infections with higher rates of progression to pneumonia and mortality compared to immunocompetent individuals. Prolonged high-titre viral shedding is common in patients with haematological malignancies and may enhance not only viral transmission, but also the selection of resistant strains. Influenza and respiratory syncytial virus (RSV) infections have been particularly well studied. They are associated with pneumonia rates of about one-third for influenza and 30–40% for RSV. Both viruses are responsible for mortality rates ranging from 15% to 30%. The exact mechanisms of pneumonia related to these viruses remains unknown, but bacterial and fungal co-infections are frequent and must be carefully investigated. Parainfluenza viruses (PIV) and RSV have also been linked to late airflow obstruction in haematopoietic stem cell transplant recipients. Neuraminidase inhibitor therapy has been suggested for influenza, ribavirin for RSV, and cidofovir for adenovirus infections. However, there is no evidence supporting the use of these drugs, and randomised controlled trials are urgently needed to better define the optimal management of common viral pneumonia in patients with haematological malignancies. The absence of proven effective treatments highlights the critical importance of prevention. Viral transmission may be interrupted by contact isolation with droplet precautions for infected patients and by having patients and health care workers with suspected infection, and their relatives, refrain from visits and work. Immunisation remains the cornerstone of influenza prevention and is recommended for patients with haematological malignancies, their relatives, and health care workers.
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231
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Salter A, Laoi BN, Crowley B. Molecular epidemiology of human respiratory syncytial virus subgroups A and B identified in adults with hematological malignancy attending an Irish hospital between 2004 and 2009. J Med Virol 2010; 83:337-47. [DOI: 10.1002/jmv.21957] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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232
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Effects of human respiratory syncytial virus, metapneumovirus, parainfluenza virus 3 and influenza virus on CD4+ T cell activation by dendritic cells. PLoS One 2010; 5:e15017. [PMID: 21124776 PMCID: PMC2993941 DOI: 10.1371/journal.pone.0015017] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 10/11/2010] [Indexed: 12/24/2022] Open
Abstract
Background Human respiratory syncytial virus (HRSV), and to a lesser extent human metapneumovirus (HMPV) and human parainfluenza virus type 3 (HPIV3), re-infect symptomatically throughout life without antigenic change, suggestive of incomplete immunity. One causative factor is thought to be viral interference with dendritic cell (DC)-mediated stimulation of CD4+ T cells. Methodology, Principal Findings We infected human monocyte-derived DC with purified HRSV, HMPV, HPIV3, or influenza A virus (IAV) and compared their ability to induce activation and proliferation of autologous CD4+ T cells in vitro. IAV was included because symptomatic re-infection without antigenic change is less frequent, suggesting that immune protection is more complete and durable. We examined virus-specific memory responses and superantigen-induced responses by multiparameter flow cytometry. Live virus was more stimulatory than inactivated virus in inducing DC-mediated proliferation of virus-specific memory CD4+ T cells, suggesting a lack of strong suppression by live virus. There were trends of increasing proliferation in the order: HMPV<HRSV<HPIV3<IAV, and greater production of interferon-γ and tumor necrosis factor-α by proliferating cells in response to IAV, but differences were not significant. Exposure of DC to HRSV, HPIV3, or IAV reduced CD4+ T cell proliferation in response to secondary stimulus with superantigen, but the effect was transitory and greatest for IAV. T cell cytokine production was similar, with no evidence of Th2 or Th17 skewing. Conclusions, Significance Understanding the basis for the ability of HRSV in particular to symptomatically re-infect without significant antigenic change is of considerable interest. The present results show that these common respiratory viruses are similar in their ability to induce DC to activate CD4+ T cells. Thus, the results do not support the common model in which viral suppression of CD4+ T cell activation and proliferation by HRSV, HMPV, and HPIV3 is a major factor in the difference in re-infectability compared to IAV.
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Gowdy KM, Krantz QT, King C, Boykin E, Jaspers I, Linak WP, Gilmour MI. Role of oxidative stress on diesel-enhanced influenza infection in mice. Part Fibre Toxicol 2010; 7:34. [PMID: 21092162 PMCID: PMC3001415 DOI: 10.1186/1743-8977-7-34] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Accepted: 11/22/2010] [Indexed: 01/05/2023] Open
Abstract
Numerous studies have shown that air pollutants, including diesel exhaust (DE), reduce host defenses, resulting in decreased resistance to respiratory infections. This study sought to determine if DE exposure could affect the severity of an ongoing influenza infection in mice, and examine if this could be modulated with antioxidants. BALB/c mice were treated by oropharyngeal aspiration with 50 plaque forming units of influenza A/HongKong/8/68 and immediately exposed to air or 0.5 mg/m3 DE (4 hrs/day, 14 days). Mice were necropsied on days 1, 4, 8 and 14 post-infection and lungs were assessed for virus titers, lung inflammation, immune cytokine expression and pulmonary responsiveness (PR) to inhaled methacholine. Exposure to DE during the course of infection caused an increase in viral titers at days 4 and 8 post-infection, which was associated with increased neutrophils and protein in the BAL, and an early increase in PR. Increased virus load was not caused by decreased interferon levels, since IFN-β levels were enhanced in these mice. Expression and production of IL-4 was significantly increased on day 1 and 4 p.i. while expression of the Th1 cytokines, IFN-γ and IL-12p40 was decreased. Treatment with the antioxidant N-acetylcysteine did not affect diesel-enhanced virus titers but blocked the DE-induced changes in cytokine profiles and lung inflammation. We conclude that exposure to DE during an influenza infection polarizes the local immune responses to an IL-4 dominated profile in association with increased viral disease, and some aspects of this effect can be reversed with antioxidants.
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Affiliation(s)
- Kymberly M Gowdy
- Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, United States Environmental Protection Agency, 109 T,W, Alexander Dr,, RTP, NC, 27711, USA
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Comas-García A, García-Sepúlveda CA, Méndez-de Lira JJ, Aranda-Romo S, Hernández-Salinas AE, Noyola DE. Mortality attributable to pandemic influenza A (H1N1) 2009 in San Luis Potosí, Mexico. Influenza Other Respir Viruses 2010; 5:76-82. [PMID: 21306570 PMCID: PMC4942002 DOI: 10.1111/j.1750-2659.2010.00187.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Acute respiratory infections are a leading cause of morbidity and mortality worldwide. Starting in 2009, pandemic influenza A(H1N1) 2009 virus has become one of the leading respiratory pathogens worldwide. However, the overall impact of this virus as a cause of mortality has not been clearly defined. OBJECTIVES To determine the impact of pandemic influenza A(H1N1) 2009 on mortality in a Mexican population. METHODS We assessed the impact of pandemic influenza virus on mortality during the first and second outbreaks in San Luis Potosí, Mexico, and compared it to mortality associated with seasonal influenza and respiratory syncytial virus (RSV) during the previous winter seasons. RESULTS We estimated that, on average, 8·1% of all deaths that occurred during the 2003-2009 seasons were attributable to influenza and RSV. During the first pandemic influenza A(H1N1) 2009 outbreak, there was an increase in mortality in persons 5-59 years of age, but not during the second outbreak (Fall of 2009). Overall, pandemic influenza A (H1N1) 2009 outbreaks had similar effects on mortality to those associated with seasonal influenza virus epidemics. CONCLUSIONS The impact of influenza A(H1N1) 2009 virus on mortality during the first year of the pandemic was similar to that observed for seasonal influenza. The establishment of real-time surveillance systems capable of integrating virological, morbidity, and mortality data may result in the timely identification of outbreaks so as to allow for the institution of appropriate control measures to reduce the impact of emerging pathogens on the population.
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Affiliation(s)
- Andreu Comas-García
- Microbiology Department, Facultad de Medicina, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México
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Real-time detection of influenza a, influenza B, and respiratory syncytial virus a and B in respiratory specimens by use of nanoparticle probes. J Clin Microbiol 2010; 48:3997-4002. [PMID: 20826644 DOI: 10.1128/jcm.01118-10] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Seasonal epidemics of influenza and respiratory syncytial virus are responsible for significant morbidity and mortality worldwide. Infrequently, novel or reemergent strains of influenza A virus have caused rapid, severe global pandemics resulting in millions of fatalities. The ability to efficiently and accurately detect and differentiate respiratory viruses is paramount for effective treatment, infection control, and epidemiological surveillance. We evaluated the ability of two FDA-cleared nucleic acid-based tests, the semiautomated respiratory virus nucleic acid test (VRNAT) and the fully automated respiratory virus nucleic acid test SP (RVNAT(SP)) (Nanosphere Inc., Northbrook, IL) to detect influenza A virus, influenza B virus, and respiratory syncytial virus A and B (RSV A/B) from clinical nasopharyngeal swab specimens. Detection of viral RNA in both tests is based on nucleic acid amplification followed by hybridization to capture probes immobilized on a glass slide. A novel technology utilizing gold nanoparticle-conjugated probes is utilized to detect the presence of captured target DNA. This microarray-based approach to detection has proven to be more sensitive than the traditional culture/direct fluorescent-antibody assay (DFA) method for detecting RSV and influenza viruses in clinical specimens, including the novel 2009 H1N1 strain. Specifically, we report 98.0% sensitivity and 96.5% specificity for the VRNAT compared to culture/DFA. Further, the VRNAT detected virus in an additional 58% of specimens that were culture negative. These data were confirmed using bidirectional sequencing. Evaluation of the fully automated RVNAT(SP), which is built on the same detection technology as the VRNAT but contains an updated processor enabling complete automation, revealed the two tests to be functionally equivalent. Thus, the RVNAT(SP) is a fully automated sample-to-result test capable of reliable detection of select respiratory viruses directly from clinical specimens in 3.5 h.
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Pharmacokinetics-pharmacodynamics of a respiratory syncytial virus fusion inhibitor in the cotton rat model. Antimicrob Agents Chemother 2010; 54:4534-9. [PMID: 20823290 DOI: 10.1128/aac.00643-10] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Human respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections in infants, young children, elderly persons, and severely immunocompromised patients. Effective postinfection treatments are not widely available, and currently there is no approved vaccine. TMC353121 is a potent RSV fusion inhibitor in vitro, and its ability to reduce viral loads in vivo was demonstrated in cotton rats following prophylactic intravenous administration. Here, the pharmacokinetics of TMC353121 in the cotton rat, which is semipermissive for RSV replication, were further explored to build a pharmacokinetic-pharmacodynamic (PK-PD) model and to estimate the plasma drug levels needed for significant antiviral efficacy. TMC353121 reduced the viral titers in bronchoalveolar lavage fluid in a dose-dependent manner after a single subcutaneous administration and intranasal RSV inoculation 24 h after compound administration. The viral titer reduction and plasma TMC353121 concentration at the time of RSV inoculation were well described using a simple E(max) model with a maximal viral titer reduction (E(max)) of 1.5 log(10). The plasma drug level required to achieve 50% of the E(max) (200 ng/ml) was much higher than the 50% inhibitory concentration observed in vitro in HeLaM cells (0.07 ng/ml). In conclusion, this simple PK-PD approach may be useful in predicting efficacious exposure levels for future RSV inhibitors.
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Magro M, Andreu D, Gómez-Puertas P, Melero JA, Palomo C. Neutralization of human respiratory syncytial virus infectivity by antibodies and low-molecular-weight compounds targeted against the fusion glycoprotein. J Virol 2010; 84:7970-82. [PMID: 20534864 PMCID: PMC2916552 DOI: 10.1128/jvi.00447-10] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Accepted: 05/25/2010] [Indexed: 11/20/2022] Open
Abstract
Human respiratory syncytial virus (HRSV) fusion (F) protein is an essential component of the virus envelope that mediates fusion of the viral and cell membranes, and, therefore, it is an attractive target for drug and vaccine development. Our aim was to analyze the neutralizing mechanism of anti-F antibodies in comparison with other low-molecular-weight compounds targeted against the F molecule. It was found that neutralization by anti-F antibodies is related to epitope specificity. Thus, neutralizing and nonneutralizing antibodies could bind equally well to virions and remained bound after ultracentrifugation of the virus, but only the former inhibited virus infectivity. Neutralization by antibodies correlated with inhibition of cell-cell fusion in a syncytium formation assay, but not with inhibition of virus binding to cells. In contrast, a peptide (residues 478 to 516 of F protein [F478-516]) derived from the F protein heptad repeat B (HRB) or the organic compound BMS-433771 did not interfere with virus infectivity if incubated with virus before ultracentrifugation or during adsorption of virus to cells at 4 degrees C. These inhibitors must be present during virus entry to effect HRSV neutralization. These results are best interpreted by asserting that neutralizing antibodies bind to the F protein in virions interfering with its activation for fusion. Binding of nonneutralizing antibodies is not enough to block this step. In contrast, the peptide F478-516 or BMS-433771 must bind to F protein intermediates generated during virus-cell membrane fusion, blocking further development of this process.
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Affiliation(s)
- Margarita Magro
- Laboratorio de Biología Viral, Centro Nacional de Microbiología and CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain, Departamento de Ciencias Experimentales y de la Salud, Universidad Pompeu Fabra, 08003 Barcelona, Spain, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Cantoblanco, 28049 Madrid, Spain, CIBER Fisiopatología de la Obesidad y la Nutrición (CB06/03), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - David Andreu
- Laboratorio de Biología Viral, Centro Nacional de Microbiología and CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain, Departamento de Ciencias Experimentales y de la Salud, Universidad Pompeu Fabra, 08003 Barcelona, Spain, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Cantoblanco, 28049 Madrid, Spain, CIBER Fisiopatología de la Obesidad y la Nutrición (CB06/03), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Paulino Gómez-Puertas
- Laboratorio de Biología Viral, Centro Nacional de Microbiología and CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain, Departamento de Ciencias Experimentales y de la Salud, Universidad Pompeu Fabra, 08003 Barcelona, Spain, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Cantoblanco, 28049 Madrid, Spain, CIBER Fisiopatología de la Obesidad y la Nutrición (CB06/03), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - José A. Melero
- Laboratorio de Biología Viral, Centro Nacional de Microbiología and CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain, Departamento de Ciencias Experimentales y de la Salud, Universidad Pompeu Fabra, 08003 Barcelona, Spain, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Cantoblanco, 28049 Madrid, Spain, CIBER Fisiopatología de la Obesidad y la Nutrición (CB06/03), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Concepción Palomo
- Laboratorio de Biología Viral, Centro Nacional de Microbiología and CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain, Departamento de Ciencias Experimentales y de la Salud, Universidad Pompeu Fabra, 08003 Barcelona, Spain, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Cantoblanco, 28049 Madrid, Spain, CIBER Fisiopatología de la Obesidad y la Nutrición (CB06/03), Instituto de Salud Carlos III, 28029, Madrid, Spain
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Blanco JCG, Boukhvalova MS, Shirey KA, Prince GA, Vogel SN. New insights for development of a safe and protective RSV vaccine. HUMAN VACCINES 2010; 6:482-92. [PMID: 20671419 PMCID: PMC2965816 DOI: 10.4161/hv.6.6.11562] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Respiratory Syncytial Virus (RSV) is the leading cause of pneumonia and bronchiolitis in infants and children <1 year old, resulting in significant morbidity and mortality worldwide. There is currently no RSV vaccine. In the 1960s, a formalin-inactivated RSV (FI-RSV) vaccine trial led to exacerbated disease upon natural infection of vaccinees, including two deaths. The causes involved in the disastrous results of these vaccine trials are still unclear but they remain the engine for searching new avenues to develop a safe vaccine that can provide long-term protection against this important pathogen. This article reviews some of the early history of RSV vaccine development,as well as more recent information on the interaction between RSV and the host innate and adaptive immune responses. A safe and efficacious vaccine for RSV will require "re-education" of the host immune response against RSV to prevent vaccine-enhanced or severe RSV disease.
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Ten years of global evolution of the human respiratory syncytial virus BA genotype with a 60-nucleotide duplication in the G protein gene. J Virol 2010; 84:7500-12. [PMID: 20504933 DOI: 10.1128/jvi.00345-10] [Citation(s) in RCA: 145] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The emergence of natural isolates of human respiratory syncytial virus group B (HRSV-B) with a 60-nucleotide (nt) duplication in the G protein gene in Buenos Aires, Argentina, in 1999 (A. Trento et al., J. Gen. Virol. 84:3115-3120, 2003) and their dissemination worldwide allowed us to use the duplicated segment as a natural tag to examine in detail the evolution of HRSV during propagation in its natural host. Viruses with the duplicated segment were all clustered in a new genotype, named BA (A. Trento et al., J. Virol. 80:975-984, 2006). To obtain information about the prevalence of these viruses in Spain, we tested for the presence of the duplicated segment in positive HRSV-B clinical samples collected at the Severo Ochoa Hospital (Madrid) during 12 consecutive epidemics (1996-1997 to 2007-2008). Viruses with the 60-nt duplication were found in 61 samples, with a high prevalence relative to the rest of B genotypes in the most recent seasons. Global phylogenetic and demographic analysis of all G sequences containing the duplication, collected across five continents up until April 2009, revealed that the prevalence of the BA genotype increased gradually until 2004-2005, despite its rapid dissemination worldwide. After that date and coinciding with a bottleneck effect on the population size, a relatively new BA lineage (BA-IV) replaced all other group B viruses, suggesting further adaptation of the BA genotype to its natural host.
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Hutchinson AF, Black J, Thompson MA, Bozinovski S, Brand CA, Smallwood DM, Irving LB, Anderson GP. Identifying viral infections in vaccinated Chronic Obstructive Pulmonary Disease (COPD) patients using clinical features and inflammatory markers. Influenza Other Respir Viruses 2010; 4:33-9. [PMID: 20021505 PMCID: PMC4941951 DOI: 10.1111/j.1750-2659.2009.00113.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Background Known inflammatory markers have limited sensitivity and specificity to differentiate viral respiratory tract infections from other causes of acute exacerbation of COPD (AECOPD). To overcome this, we developed a multi‐factorial prediction model combining viral symptoms with inflammatory markers. Methods Interleukin‐6 (IL‐6), serum amyloid A (SAA) and viral symptoms were measured in stable COPD and at AECOPD onset and compared with the viral detection rates on multiplex PCR. The predictive accuracy of each measure was assessed using logistic regression and receiver operating characteristics curve (ROC) analysis. Results There was a total of 33 viruses detected at the onset of 148 AECOPD, the majority 26 (79%) were picornavirus. Viral symptoms with the highest predictive values were rhinorrhoea [Odds ratio (OR) 4·52; 95% CI 1·99–10·29; P < 0·001] and sore throat (OR 2·64; 95% CI 1·14–6·08; P = 0·022), combined the AUC ROC curve was 0·67. At AECOPD onset patients experienced a 1·6‐fold increase in IL‐6 (P = 0·008) and 4·5‐fold increase in SAA (P < 0·001). The addition of IL‐6 to the above model significantly improved diagnostic accuracy compared with symptoms alone (AUC ROC 0·80 (P = 0·012). Conclusion The addition of inflammatory markers increases the specificity of a clinical case definition for viral infection, particularly picornavirus infection.
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Affiliation(s)
- Anastasia F Hutchinson
- Department of Medicine, Melbourne University, Parkville, Melbourne, Victoria, 3056, Australia
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Variation of respiratory syncytial virus and the relation with meteorological factors in different winter seasons. Pediatr Infect Dis J 2009; 28:860-6. [PMID: 20118684 DOI: 10.1097/inf.0b013e3181a3e949] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Respiratory syncytial virus (RSV) is the most important viral agent causing severe respiratory disease in infants and children. In temperate climates, RSV activity typically peaks during winter. We have described the seasonal variation in RSV activity and investigated which meteorological variables are related to RSV outbreaks for different time lags. METHODS Eleven laboratories in the Netherlands collected data on RSV during the period 1998-2005. Meteorological data were obtained from the Royal Netherlands Meteorological Institute. General linear methods were used to determine the relative contribution of meteorological conditions to reported RSV cases in the winter period. Time lags up to 4 weeks were included to assess a possible delayed weather effect in relation to RSV activity. RESULTS Onset of RSV activity occurred around week 44 and activity peaked around week 52. Timing of peak activity was very consistent over the study period. Relative humidity was positively associated with RSV activity for all time lags, indicating more RSV when relative humidity increased. Minimum temperature was negatively associated with RSV activity and cloud cover was positively related with RSV activity. Interaction (P < 0.06) between minimum temperature and relative humidity was observed for a lag of 0, 1, and 2 weeks, indicating that the combination of low temperature and high humidity contributes more to RSV activity than temperature and humidity alone. CONCLUSIONS Relative humidity, minimum temperature, and cloud cover are important predictors of RSV activity in the Netherlands, with the effect of relative humidity being most consistent.
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Respiratory syncytial virus grown in Vero cells contains a truncated attachment protein that alters its infectivity and dependence on glycosaminoglycans. J Virol 2009; 83:10710-8. [PMID: 19656891 DOI: 10.1128/jvi.00986-09] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human respiratory syncytial virus (RSV) contains a heavily glycosylated 90-kDa attachment glycoprotein (G). Infection of HEp-2 and Vero cells in culture depends largely on virion G protein binding to cell surface glycosaminoglycans (GAGs). This GAG-dependent phenotype has been described for RSV grown in HEp-2 cells, but we have found that it is greatly reduced by a single passage in Vero cells. Virions produced from Vero cells primarily display a 55-kDa G glycoprotein. This smaller G protein represents a post-Golgi compartment form that is lacking its C terminus, indicating that the C terminus is required for GAG dependency. Vero cell-grown virus infected primary well-differentiated human airway epithelial (HAE) cell cultures 600-fold less efficiently than did HEp-2 cell-grown virus, indicating that the C terminus of the G protein is also required for virus attachment to this model of the in vivo target cells. This reduced infectivity for HAE cell cultures is not likely to be due to the loss of GAG attachment since heparan sulfate, the primary GAG used by RSV for attachment to HEp-2 cells, is not detectable at the apical surface of HAE cell cultures where RSV enters. Growing RSV stocks in Vero cells could dramatically reduce the initial infection of the respiratory tract in animal models or in volunteers receiving attenuated virus vaccines, thereby reducing the efficiency of infection or the efficacy of the vaccine.
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Adair BM. Nanoparticle vaccines against respiratory viruses. WILEY INTERDISCIPLINARY REVIEWS. NANOMEDICINE AND NANOBIOTECHNOLOGY 2009; 1:405-14. [PMID: 20049806 PMCID: PMC7169756 DOI: 10.1002/wnan.45] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Influenza virus, respiratory syncytial virus (RSV), and parainfluenza type 3 virus (PI-3V) are the major viral agents which are consistently involved in causing lower respiratory tract disease in humans and animals. The virus infection begins in the upper respiratory tract, where immune responses are initiated, and then progresses to the lower respiratory tract where destruction of cells and tissues leads to bronchitis, bronchiolitis, and pneumonia, which is occasionally fatal. Nanoparticle vaccines, incorporating antigenic components from influenza, RSV, or PI-3V have been shown to be capable of stimulating mucosal and systemic immune responses, which can prevent the spread of infection to the lower respiratory tract. The encapsulation of viral proteins within nanoparticles may also facilitate production of respiratory vaccines which are efficacious in infants, where presence of maternally derived antibodies can reduce vaccine efficacy.
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Affiliation(s)
- Brian M Adair
- Virology Department, Veterinary Sciences Division, Agri-Food and Biosciences Institute, Stormont, Belfast, Northern Ireland, UK.
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Bharaj P, Sullender WM, Kabra SK, Mani K, Cherian J, Tyagi V, Chahar HS, Kaushik S, Dar L, Broor S. Respiratory viral infections detected by multiplex PCR among pediatric patients with lower respiratory tract infections seen at an urban hospital in Delhi from 2005 to 2007. Virol J 2009; 6:89. [PMID: 19558656 PMCID: PMC2709894 DOI: 10.1186/1743-422x-6-89] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2009] [Accepted: 06/26/2009] [Indexed: 02/06/2023] Open
Abstract
Background Acute lower respiratory tract infections (ALRI) are the major cause of morbidity and mortality in young children worldwide. Information on viral etiology in ALRI from India is limited. The aim of the present study was to develop a simple, sensitive, specific and cost effective multiplex PCR (mPCR) assay without post PCR hybridization or nested PCR steps for the detection of respiratory syncytial virus (RSV), influenza viruses, parainfluenza viruses (PIV1–3) and human metapneumovirus (hMPV). Nasopharyngeal aspirates (NPAs) were collected from children with ALRI ≤ 5 years of age. The sensitivity and specificity of mPCR was compared to virus isolation by centrifugation enhanced culture (CEC) followed by indirect immunofluorescence (IIF). Results From April 2005–March 2007, 301 NPAs were collected from children attending the outpatient department or admitted to the ward of All India Institute of Medical Sciences hospital at New Delhi, India. Multiplex PCR detected respiratory viruses in 106 (35.2%) of 301 samples with 130 viruses of which RSV was detected in 61, PIV3 in 22, PIV2 in 17, hMPV in 11, PIV1 in 10 and influenza A in 9 children. CEC-IIF detected 79 viruses only. The sensitivity of mPCR was 0.1TCID50 for RSV and influenza A and 1TCID50 for hMPV, PIV1, PIV2, PIV3 and Influenza B. Mixed infections were detected in 18.8% of the children with viral infections, none detected by CEC-IIF. Bronchiolitis was significantly associated with both total viral infections and RSV infection (p < 0.05). History of ARI in family predisposed children to acquire viral infection (p > 0.05). Conclusion Multiplex PCR offers a rapid, sensitive and reasonably priced diagnostic method for common respiratory viruses.
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Affiliation(s)
- Preeti Bharaj
- Department of Microbiology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India.
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Santamaría C, Urueña A, Videla C, Suarez A, Ganduglia C, Carballal G, Bonvehi P, Echavarría M. Epidemiological study of influenza virus infections in young adult outpatients from Buenos Aires, Argentina. Influenza Other Respir Viruses 2009; 2:131-4. [PMID: 19453464 PMCID: PMC4634226 DOI: 10.1111/j.1750-2659.2008.00048.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Background Influenza virus is the most common cause of influenza‐like illness (ILI) in adults. In Argentina, studies on influenza and other respiratory viruses were performed mostly in pediatric populations. Objectives To determine: (1) the frequency of influenza virus and other common respiratory viruses in adult outpatients with ILI, (2) whether the signs and symptoms predict viral etiology, (3) whether viral diagnosis changes clinical management or infection control measures and (4) to characterize the influenza strains circulating in the community. Population and methods Nasal and pharyngeal swabs from adult outpatients with ILI attending the emergency room during the winter seasons of 2004 and 2005 in Argentina were evaluated by immunofluorescence and RT‐PCR. Results Of 151 samples analyzed, 39 (26%) were influenza A positive, 5 (3·3%) influenza B positive and 4 (2·6%) respiratory syncytial virus positive by immunofluorescence. Two samples (1·3%) were human metapneumovirus positive by RT PCR. Cell culture detected six additional influenza viruses and one adenovirus positive sample. The sensitivity of immunofluorescence for influenza compared with culture was 70%. Symptoms did not predict etiology. Conclusions In this study, 40% of the patients with ILI had a specific viral infection and 83% were influenza viruses. Viral detection was necessary to determine the etiology as signs and symptoms were not different between patients with or without viral infection. Viral diagnosis was important to implement infectious control measures. Circulating influenza strains in this study were similar to the correspondent vaccine strains selected for the Southern hemisphere.
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O'Shea MK, Pipkin C, Cane PA, Gray GC. Respiratory syncytial virus: an important cause of acute respiratory illness among young adults undergoing military training. Influenza Other Respir Viruses 2009; 1:193-7. [PMID: 18846262 PMCID: PMC2564797 DOI: 10.1111/j.1750-2659.2007.00029.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Background Military recruits receiving training are vulnerable to acute respiratory disease and a significant proportion of illness is caused by unidentified pathogens. While some countries use surveillance programmes to monitor such illness, few data exist for recruits of the British Armed Forces. Objectives Through active surveillance of approximately 1000 Royal Navy trainees during 2001, we sought to describe and determine the aetiology of acute respiratory illness. Methods Standard viral culture was used together with serology and a novel highly sensitive real‐time PCR and molecular beacon probe assay for respiratory syncytial virus (RSV) detection. Results Among 54 Royal Navy recruits with respiratory symptoms adenovirus was identified in 35%, influenza viruses in 19% and RSV in 14%. All recruits were absent from training for almost a week, most of whom were confined to the sickbay. Conclusions This study is the first to document adenovirus and RSV as important causes of acute respiratory illness among Royal Navy trainees. The study findings demonstrate the clinical significance and challenges of diagnosing RSV infection in young adults.
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Affiliation(s)
- Matthew K O'Shea
- The Institute of Naval Medicine, Alverstoke, Gosport, Hampshire, UK
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247
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RNA interference-mediated silencing of the respiratory syncytial virus nucleocapsid defines a potent antiviral strategy. Antimicrob Agents Chemother 2009; 53:3952-62. [PMID: 19506055 DOI: 10.1128/aac.00014-09] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
We describe the design and characterization of a potent human respiratory syncytial virus (RSV) nucleocapsid gene-specific small interfering RNA (siRNA), ALN-RSV01. In in vitro RSV plaque assays, ALN-RSV01 showed a 50% inhibitory concentration of 0.7 nM. Sequence analysis of primary isolates of RSV showed that the siRNA target site was absolutely conserved in 89/95 isolates, and ALN-RSV01 demonstrated activity against all isolates, including those with single-mismatch mutations. In vivo, intranasal dosing of ALN-RSV01 in a BALB/c mouse model resulted in potent antiviral efficacy, with 2.5- to 3.0-log-unit reductions in RSV lung concentrations being achieved when ALN-RSV01 was administered prophylactically or therapeutically in both single-dose and multidose regimens. The specificity of ALN-RSV01 was demonstrated in vivo by using mismatch controls; and the absence of an immune stimulatory mechanism was demonstrated by showing that nonspecific siRNAs that induce alpha interferon and tumor necrosis factor alpha lack antiviral efficacy, while a chemically modified form of ALN-RSV01 lacking measurable immunostimulatory capacity retained full activity in vivo. Furthermore, an RNA interference mechanism of action was demonstrated by the capture of the site-specific cleavage product of the RSV mRNA via rapid amplification of cDNA ends both in vitro and in vivo. These studies lay a solid foundation for the further investigation of ALN-RSV01 as a novel therapeutic antiviral agent for clinical use by humans.
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248
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Schanzer DL, Langley JM, Tam TWS. Role of influenza and other respiratory viruses in admissions of adults to Canadian hospitals. Influenza Other Respir Viruses 2009; 2:1-8. [PMID: 19453488 PMCID: PMC4634329 DOI: 10.1111/j.1750-2659.2008.00035.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE We sought to estimate age-specific hospitalization rates attributed to influenza and other virus for adults. METHODS Admissions from Canada's national hospitalization database (Canadian Institute of Health Information), from 1994/95 to 1999/2000, were modeled as a function of proxy variables for influenza, respiratory syncytial virus (RSV) and other viral activity, seasonality and trend using a Poisson regression model and stratified by age group. RESULTS The average annual influenza-attributed hospitalization rate for all adults, 20 years of age or older, over the study period, which included three severe seasons, was an estimated 65/100,000 population (95% CI 63-67). Among persons aged 65 and over, 270-340 admissions per 100,000 population per year were attributed to influenza, while 30-110, 60-90 and 130-350 per 100,000 were attributed to RSV, parainfluenza (PIV) and other respiratory viruses, respectively. Although marked season-to-season variation in age-specific hospitalization rates attributable to influenza was observed in persons 50 years of age and older, increasing risk with age was preserved at all time periods. CONCLUSIONS Influenza, RSV, PIV and other respiratory viruses were all associated with morbidity requiring hospitalization, while influenza was responsible for peak respiratory admissions. The burden of health care utilization associated with respiratory viruses is appreciable beginning in the sixth decade and increases significantly with age.
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Affiliation(s)
- Dena L Schanzer
- Centre for Infectious Disease Prevention and Control, Public Health Agency of Canada, Ottawa, ON, Canada.
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Abstract
Although respiratory syncytial virus (RSV) was discovered > 40 years ago, treatment remains largely supportive. There are no safe and effective vaccines or specific treatments other than prophylaxis with passive antibody therapy (palivizumab). However, there are good reasons to think that the scene may soon change. As the pace of development of anti-viral drugs accelerates and optimism over vaccines increases, novel therapies are set to make a major impact in the management of this very common infection. The use and effect of such interventions are not easy to anticipate, but could ultimately include the interruption of RSV's transmission resulting in profound changes to the impact of RSV on human health.
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Affiliation(s)
- Wieslawa Olszewska
- National Heart and Lung Institute, Centre for Respiratory Infection, Imperial College London, St Mary's Campus, Norfolk Place, Paddington, W2 1PG, London, UK
| | - Peter Openshaw
- National Heart and Lung Institute, Centre for Respiratory Infection, Imperial College London, St Mary's Campus, Norfolk Place, Paddington, W2 1PG, London, UK
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Identification of gene biomarkers for respiratory syncytial virus infection in a bronchial epithelial cell line. Genomic Med 2009; 2:113-25. [PMID: 19459069 DOI: 10.1007/s11568-009-9080-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Revised: 04/14/2009] [Accepted: 04/24/2009] [Indexed: 12/26/2022] Open
Abstract
Respiratory syncytial virus (RSV) infection involves complex virus-host interplay. In this study, we analyzed gene expression in RSV-infected BEAS-2B cells to discover novel signaling pathways and biomarkers. We hybridized RNAs from RSV- or vehicle-treated BEAS-2B to Affymetrix HU133 plus 2.0 microarrays (n = 4). At 4 and 24 h post-infection, 277 and 900 genes (RSV/control ratio >/=2.0 or </=0.5), and 1 and 12 pathways respectively were significantly altered. Twenty-three and 92 genes at 4 and 24 h respectively matched respiratory disease biomarkers with ARG2 flagged at 24 h and SCNN1G, EPB41L4B, CSF1, PTEN, TUBB1 and ESR2 at both time points. Hierachical clustering showed a cluster containing ARG2 and IL8. In human bronchial epithelial cells, RSV upregulated arginase II protein. Knockdown of ARG2 increased RSV-induced IL-8, LDH and histone release. With microarray, we identified novel proximal airway epithelial cell genes that may be tested in the sputum samples as biomarkers of RSV infection.
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