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Piloto JV, Dias RVR, Mazucato WSA, Fossey MA, de Melo FA, Almeida FCL, de Souza FP, Caruso IP. Computational Insights into the Interaction of the Conserved Cysteine-Noose Domain of the Human Respiratory Syncytial Virus G Protein with the Canonical Fractalkine Binding site of Transmembrane Receptor CX3CR1 Isoforms. MEMBRANES 2024; 14:84. [PMID: 38668112 PMCID: PMC11052111 DOI: 10.3390/membranes14040084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 03/23/2024] [Accepted: 03/27/2024] [Indexed: 04/28/2024]
Abstract
The human Respiratory Syncytial Virus (hRSV) stands as one of the most common causes of acute respiratory diseases. The infectivity of this virus is intricately linked to its membrane proteins, notably the attachment glycoprotein (G protein). The latter plays a key role in facilitating the attachment of hRSV to respiratory tract epithelial cells, thereby initiating the infection process. The present study aimed to characterize the interaction of the conserved cysteine-noose domain of hRSV G protein (cndG) with the transmembrane CX3C motif chemokine receptor 1 (CX3CR1) isoforms using computational tools of molecular modeling, docking, molecular dynamics simulations, and binding free energy calculations. From MD simulations of the molecular system embedded in the POPC lipid bilayer, we showed a stable interaction of cndG with the canonical fractalkine binding site in the N-terminal cavity of the CX3CR1 isoforms and identified that residues in the extracellular loop 2 (ECL2) region and Glu279 of this receptor are pivotal for the stabilization of CX3CR1/cndG binding, corroborating what was reported for the interaction of the chemokine fractalkine with CX3CR1 and its structure homolog US28. Therefore, the results presented here contribute by revealing key structural points for the CX3CR1/G interaction, allowing us to better understand the biology of hRSV from its attachment process and to develop new strategies to combat it.
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Affiliation(s)
- João Victor Piloto
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São Jose do Rio Preto 15054-000, Brazil; (J.V.P.); (R.V.R.D.); (W.S.A.M.); (M.A.F.); (F.A.d.M.); (F.P.d.S.)
| | - Raphael Vinicius Rodrigues Dias
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São Jose do Rio Preto 15054-000, Brazil; (J.V.P.); (R.V.R.D.); (W.S.A.M.); (M.A.F.); (F.A.d.M.); (F.P.d.S.)
| | - Wan Suk Augusto Mazucato
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São Jose do Rio Preto 15054-000, Brazil; (J.V.P.); (R.V.R.D.); (W.S.A.M.); (M.A.F.); (F.A.d.M.); (F.P.d.S.)
| | - Marcelo Andres Fossey
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São Jose do Rio Preto 15054-000, Brazil; (J.V.P.); (R.V.R.D.); (W.S.A.M.); (M.A.F.); (F.A.d.M.); (F.P.d.S.)
| | - Fernando Alves de Melo
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São Jose do Rio Preto 15054-000, Brazil; (J.V.P.); (R.V.R.D.); (W.S.A.M.); (M.A.F.); (F.A.d.M.); (F.P.d.S.)
| | - Fabio Ceneviva Lacerda Almeida
- Institute of Medical Biochemistry (IBqM), National Center of Nuclear Magnetic Resonance Jiri Jonas, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil;
| | - Fatima Pereira de Souza
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São Jose do Rio Preto 15054-000, Brazil; (J.V.P.); (R.V.R.D.); (W.S.A.M.); (M.A.F.); (F.A.d.M.); (F.P.d.S.)
| | - Icaro Putinhon Caruso
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São Jose do Rio Preto 15054-000, Brazil; (J.V.P.); (R.V.R.D.); (W.S.A.M.); (M.A.F.); (F.A.d.M.); (F.P.d.S.)
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Genomic analysis of respiratory syncytial virus infections in households and utility in inferring who infects the infant. Sci Rep 2019; 9:10076. [PMID: 31296922 PMCID: PMC6624209 DOI: 10.1038/s41598-019-46509-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 06/26/2019] [Indexed: 12/18/2022] Open
Abstract
Infants (under 1-year-old) are at most risk of life threatening respiratory syncytial virus (RSV) disease. RSV epidemiological data alone has been insufficient in defining who acquires infection from whom (WAIFW) within households. We investigated RSV genomic variation within and between infected individuals and assessed its potential utility in tracking transmission in households. Over an entire single RSV season in coastal Kenya, nasal swabs were collected from members of 20 households every 3-4 days regardless of symptom status and screened for RSV nucleic acid. Next generation sequencing was used to generate >90% RSV full-length genomes for 51.1% of positive samples (191/374). Single nucleotide polymorphisms (SNPs) observed during household infection outbreaks ranged from 0-21 (median: 3) while SNPs observed during single-host infection episodes ranged from 0-17 (median: 1). Using the viral genomic data alone there was insufficient resolution to fully reconstruct within-household transmission chains. For households with clear index cases, the most likely source of infant infection was via a toddler (aged 1 to <3 years-old) or school-aged (aged 6 to <12 years-old) co-occupant. However, for best resolution of WAIFW within households, we suggest an integrated analysis of RSV genomic and epidemiological data.
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The Central Conserved Region (CCR) of Respiratory Syncytial Virus (RSV) G Protein Modulates Host miRNA Expression and Alters the Cellular Response to Infection. Vaccines (Basel) 2017; 5:vaccines5030016. [PMID: 28671606 PMCID: PMC5620547 DOI: 10.3390/vaccines5030016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 06/23/2017] [Accepted: 06/28/2017] [Indexed: 12/27/2022] Open
Abstract
Respiratory Syncytial Virus (RSV) infects respiratory epithelial cells and deregulates host gene expression by many mechanisms including expression of RSV G protein (RSV G). RSV G protein encodes a central conserved region (CCR) containing a CX3C motif that functions as a fractalkine mimic. Disruption of the CX3C motif (a.a. 182-186) located in the CCR of the G protein has been shown to affect G protein function in vitro and the severity of RSV disease pathogenesis in vivo. We show that infection of polarized Calu3 respiratory cells with recombinant RSV having point mutations in Cys173 and 176 (C173/176S) (rA2-GC12), or Cys186 (C186S) (rA2-GC4) is associated with a decline in the integrity of polarized Calu-3 cultures and decreased virus production. This is accompanied with downregulation of miRNAs let-7f and miR-24 and upregulation of interferon lambda (IFNλ), a primary antiviral cytokine for RSV in rA2-GC12/rA2-GC4 infected cells. These results suggest that residues in the cysteine noose region of RSV G protein can modulate IFN λ expression accompanied by downregulation of miRNAs, and are important for RSV G protein function and targeting.
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Shafique M, Rasool MH, Khurshid M. Respiratory syncytial virus: an overview of infection biology and vaccination strategies. Future Virol 2017. [DOI: 10.2217/fvl-2017-0120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Respiratory syncytial virus (RSV) is the foremost cause of lower respiratory tract infections, especially in infants and young children. To date, there is no licensed vaccine available for RSV. Only option to restrain RSV is a prophylactic treatment in the form of monoclonal antibody (palivizumab). However, it is quite expensive and used in few patients with co-morbidities. In ongoing research, virologists contemplate about various vaccine candidates to control RSV infection. This review will help in understating the RSV pathobiology and encompass the advancement on various vaccine candidates that would lead to reduce the incidence, mortality and morbidity. Furthermore, it will lighten up the different avenues which might be useful for the development of novel vaccination approaches.
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Affiliation(s)
- Muhammad Shafique
- Department of Microbiology, Government College University Faisalabad, Pakistan
| | | | - Mohsin Khurshid
- Department of Microbiology, Government College University Faisalabad, Pakistan
- College of Allied Health Professionals, Directorate of Medical Sciences, Government College University Faisalabad, Pakistan
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Agoti CN, Munywoki PK, Phan MVT, Otieno JR, Kamau E, Bett A, Kombe I, Githinji G, Medley GF, Cane PA, Kellam P, Cotten M, Nokes DJ. Transmission patterns and evolution of respiratory syncytial virus in a community outbreak identified by genomic analysis. Virus Evol 2017; 3:vex006. [PMID: 28458916 PMCID: PMC5399923 DOI: 10.1093/ve/vex006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Detailed information on the source, spread and evolution of respiratory syncytial virus (RSV) during seasonal community outbreaks remains sparse. Molecular analyses of attachment (G) gene sequences from hospitalized cases suggest that multiple genotypes and variants co-circulate during epidemics and that RSV persistence over successive seasons is characterized by replacement and multiple new introductions of variants. No studies have defined the patterns of introduction, spread and evolution of RSV at the local community and household level. We present a whole genome sequence analysis of 131 RSV group A viruses collected during 6-month household-based RSV infection surveillance in Coastal Kenya, 2010 within an area of 12 km2. RSV infections were identified by regular symptom-independent screening of all household members twice weekly. Phylogenetic analysis revealed that the RSV A viruses in nine households were closely related to genotype GA2 and fell within a single branch of the global phylogeny. Genomic analysis allowed the detection of household-specific variation in seven households. For comparison, using only G gene analysis, household-specific variation was found only in one of the nine households. Nucleotide changes were observed both intra-host (viruses identified from same individual in follow-up sampling) and inter-host (viruses identified from different household members) and these coupled with sampling dates enabled a partial reconstruction of the within household transmission chains. The genomic evolutionary rate for the household dataset was estimated as 2.307 × 10 − 3 (95% highest posterior density: 0.935–4.165× 10 − 3) substitutions/site/year. We conclude that (i) at the household level, most RSV infections arise from the introduction of a single virus variant followed by accumulation of household specific variation and (ii) analysis of complete virus genomes is crucial to better understand viral transmission in the community. A key question arising is whether prevention of RSV introduction or spread within the household by vaccinating key transmitting household members would lead to a reduced onward community-wide transmission.
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Affiliation(s)
- Charles N Agoti
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Collaborative Programme, Kilifi, Kenya.,School of Health and Human Sciences, Pwani University, Kilifi, Kenya
| | - Patrick K Munywoki
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Collaborative Programme, Kilifi, Kenya.,School of Health and Human Sciences, Pwani University, Kilifi, Kenya
| | - My V T Phan
- The Wellcome Trust Sanger Institute, Cambridge, UK.,Virosciences Department, Erasmus Medical Center, Rotterdam, The Netherlands
| | - James R Otieno
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Collaborative Programme, Kilifi, Kenya
| | - Everlyn Kamau
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Collaborative Programme, Kilifi, Kenya
| | - Anne Bett
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Collaborative Programme, Kilifi, Kenya
| | - Ivy Kombe
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Collaborative Programme, Kilifi, Kenya
| | - George Githinji
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Collaborative Programme, Kilifi, Kenya
| | - Graham F Medley
- Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, UK
| | - Patricia A Cane
- Virus Reference Department, Public Health England, London, UK
| | - Paul Kellam
- The Wellcome Trust Sanger Institute, Cambridge, UK.,Department of Infectious Diseases and Immunity, Imperial College London, London, UK
| | - Matthew Cotten
- The Wellcome Trust Sanger Institute, Cambridge, UK.,Virosciences Department, Erasmus Medical Center, Rotterdam, The Netherlands
| | - D James Nokes
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Collaborative Programme, Kilifi, Kenya.,School of Life Sciences and WIDER, University of Warwick, Coventry, UK
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Successive Respiratory Syncytial Virus Epidemics in Local Populations Arise from Multiple Variant Introductions, Providing Insights into Virus Persistence. J Virol 2015; 89:11630-42. [PMID: 26355091 PMCID: PMC4645665 DOI: 10.1128/jvi.01972-15] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 09/01/2015] [Indexed: 11/29/2022] Open
Abstract
Respiratory syncytial virus (RSV) is a global respiratory pathogen of humans, with infection occurring characteristically as recurrent seasonal epidemics. Unlike influenza viruses, little attention has been paid to the mechanism underlying worldwide spread and persistence of RSV and how this may be discerned through an improved understanding of the introduction and persistence of RSV in local communities. We analyzed 651 attachment (G) glycoprotein nucleotide sequences of RSV B collected over 11 epidemics (2002 to 2012) in Kilifi, Kenya, and contemporaneous data collected elsewhere in Kenya and 18 other countries worldwide (2002 to 2012). Based on phylogeny, genetic distance and clustering patterns, we set out pragmatic criteria to classify local viruses into distinct genotypes and variants, identifying those newly introduced and those locally persisting. Three genotypes were identified in the Kilifi data set: BA (n = 500), SAB1 (n = 148), and SAB4 (n = 3). Recurrent RSV epidemics in the local population were composed of numerous genetic variants, most of which have been newly introduced rather than persisting in the location from season to season. Global comparison revealed that (i) most Kilifi variants do not cluster closely with strains from outside Kenya, (ii) some Kilifi variants were closely related to those observed outside Kenya (mostly Western Europe), and (iii) many variants were circulating elsewhere but were never detected in Kilifi. These results are consistent with the hypothesis that year-to-year presence of RSV at the local level (i.e., Kilifi) is achieved primarily, but not exclusively, through introductions from a pool of variants that are geographically restricted (i.e., to Kenya or to the region) rather than global. IMPORTANCE The mechanism by which RSV persists and reinvades local populations is poorly understood. We investigated this by studying the temporal patterns of RSV variants in a rural setting in tropical Africa and comparing these variants with contemporaneous variants circulating in other countries. We found that periodic seasonal RSV transmission at the local level appears to require regular new introductions of variants. However, importantly, the evidence suggests that the source of new variants is mostly geographically restricted, and we hypothesize that year-to-year RSV persistence is at the country level rather than the global level. This has implications for control.
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Optimal control strategy for abnormal innate immune response. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2015; 2015:386235. [PMID: 25949271 PMCID: PMC4407413 DOI: 10.1155/2015/386235] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 03/20/2015] [Accepted: 03/22/2015] [Indexed: 12/22/2022]
Abstract
Innate immune response plays an important role in control and clearance of pathogens following viral infection. However, in the majority of virus-infected individuals, the response is insufficient because viruses are known to use different evasion strategies to escape immune response. In this study, we use optimal control theory to investigate how to control the innate immune response. We present an optimal control model based on an ordinary-differential-equation system from a previous study, which investigated the dynamics and regulation of virus-triggered innate immune signaling pathways, and we prove the existence of a solution to the optimal control problem involving antiviral treatment or/and interferon therapy. We conduct numerical experiments to investigate the treatment effects of different control strategies through varying the cost function and control efficiency. The results show that a separate treatment, that is, only inhibiting viral replication (u1(t)) or enhancing interferon activity (u2(t)), has more advantages for controlling viral infection than a mixed treatment, that is, controlling both (u1(t)) and (u2(t)) simultaneously, including the smallest cost and operability. These findings would provide new insight for developing effective strategies for treatment of viral infectious diseases.
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Abstract
Pulmonary infections by viruses may result in serious diseases of public health importance. The problems of the infections are exacerbated by rapid transmission of the pathogenic agents, which occur through inhalation and direct contact with contaminated surfaces. Moreover, cross-species transmission resulting from changes to viral genetic makeup poses a risk for emergence of pathogens with new characteristics, which in some cases may be responsible for causing different diseases. With the advent of efficient sequencing and nucleic acid-based virus-disabling technologies, gene therapy is well placed to advance new treatments to counter respiratory infections. Most studies aimed at using nucleic acids to treat respiratory viral infections have used RNA interference (RNAi) to silence viral gene targets. A few studies have used silencing of host factors required by the viruses as a means of inhibiting viral replication and preventing emergence of escape mutants. By administering antivirals to the airways, studies performed in vivo have taken advantage of the anatomy of the respiratory system to deliver therapeutic nucleic acids. Reported data have shown proof of principle of efficacy of gene therapy in models of respiratory syncytial virus (RSV), severe acute respiratory syndrome coronavirus, influenza virus A, and measles virus, among others. RNAi-based gene therapy has been advanced to clinical trial for treatment of RSV infection. Although the primary endpoint was not met in an intent-to-treat analysis, the investigation has provided useful information for the advancement of gene therapy for current and emergent respiratory infections.
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Interactome analysis of the human respiratory syncytial virus RNA polymerase complex identifies protein chaperones as important cofactors that promote L-protein stability and RNA synthesis. J Virol 2014; 89:917-30. [PMID: 25355874 DOI: 10.1128/jvi.01783-14] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
UNLABELLED The human respiratory syncytial virus (HRSV) core viral RNA polymerase comprises the large polymerase protein (L) and its cofactor, the phosphoprotein (P), which associate with the viral ribonucleoprotein complex to replicate the genome and, together with the M2-1 protein, transcribe viral mRNAs. While cellular proteins have long been proposed to be involved in the synthesis of HRSV RNA by associating with the polymerase complex, their characterization has been hindered by the difficulty of purifying the viral polymerase from mammalian cell culture. In this study, enhanced green fluorescent protein (EGFP)-tagged L- and P-protein expression was coupled with high-affinity anti-GFP antibody-based immunoprecipitation and quantitative proteomics to identify cellular proteins that interacted with either the L- or the P-proteins when expressed as part of a biologically active viral RNP. Several core groups of cellular proteins were identified that interacted with each viral protein including, in both cases, protein chaperones. Ablation of chaperone activity by using small-molecule inhibitors confirmed previously reported studies which suggested that this class of proteins acted as positive viral factors. Inhibition of HSP90 chaperone function in the current study showed that HSP90 is critical for L-protein function and stability, whether in the presence or absence of the P-protein. Inhibition studies suggested that HSP70 also disrupts virus biology and might help the polymerase remodel the nucleocapsid to allow RNA synthesis to occur efficiently. This indicated a proviral role for protein chaperones in HRSV replication and demonstrates that the function of cellular proteins can be targeted as potential therapeutics to disrupt virus replication. IMPORTANCE Human respiratory syncytial virus (HRSV) represents a major health care and economic burden, being the main cause of severe respiratory infections in infants worldwide. No vaccine or effective therapy is available. This study focused on identifying those cellular proteins that potentially interact specifically with the viral proteins that are central to virus replication and transcription, with a view to providing potential targets for the development of a specific, transient therapeutic which disrupts virus biology but prevents the emergence of resistance, while maintaining cell viability. In particular, protein chaperones (heat shock proteins 70 and 90), which aid protein folding and function, were identified. The mechanism by which these chaperones contribute to virus biology was tested, and this study demonstrates to the field that cellular protein chaperones may be required for maintaining the correct folding and therefore functionality of specific proteins within the virus replication complex.
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Bigogo GM, Breiman RF, Feikin DR, Audi AO, Aura B, Cosmas L, Njenga MK, Fields BS, Omballa V, Njuguna H, Ochieng PM, Mogeni DO, Aol GO, Olack B, Katz MA, Montgomery JM, Burton DC. Epidemiology of respiratory syncytial virus infection in rural and urban Kenya. J Infect Dis 2014; 208 Suppl 3:S207-16. [PMID: 24265480 DOI: 10.1093/infdis/jit489] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Information on the epidemiology of respiratory syncytial virus (RSV) infection in Africa is limited for crowded urban areas and for rural areas where the prevalence of malaria is high. METHODS At referral facilities in rural western Kenya and a Nairobi slum, we collected nasopharyngeal/oropharyngeal (NP/OP) swab specimens from patients with influenza-like illness (ILI) or severe acute respiratory illness (SARI) and from asymptomatic controls. Polymerase chain reaction assays were used for detection of viral pathogens. We calculated age-specific ratios of the odds of RSV detection among patients versus the odds among controls. Incidence was expressed as the number of episodes per 1000 person-years of observation. RESULTS Between March 2007 and February 2011, RSV was detected in 501 of 4012 NP/OP swab specimens (12.5%) from children and adults in the rural site and in 321 of 2744 NP/OP swab specimens (11.7%) from those in the urban site. Among children aged <5 years, RSV was detected more commonly among rural children with SARI (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.2-3.3), urban children with SARI (OR, 8.5; 95% CI, 3.1-23.6), and urban children with ILI (OR, 3.4; 95% CI, 1.2-9.6), compared with controls. The incidence of RSV disease was highest among infants with SARI aged <1 year (86.9 and 62.8 episodes per 1000 person-years of observation in rural and urban sites, respectively). CONCLUSIONS An effective RSV vaccine would likely substantially reduce the burden of respiratory illness among children in rural and urban areas in Africa.
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Munywoki PK, Koech DC, Agoti CN, Lewa C, Cane PA, Medley GF, Nokes DJ. The source of respiratory syncytial virus infection in infants: a household cohort study in rural Kenya. J Infect Dis 2013; 209:1685-92. [PMID: 24367040 PMCID: PMC4017365 DOI: 10.1093/infdis/jit828] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Background. Respiratory syncytial virus (RSV) vaccine development for direct protection of young infants faces substantial obstacles. Assessing the potential of indirect protection using different strategies, such as targeting older children or mothers, requires knowledge of the source of infection to the infants. Methods. We undertook a prospective study in rural Kenya. Households with a child born after the preceding RSV epidemic and ≥1 elder sibling were recruited. Nasopharyngeal swab samples were collected every 3–4 days irrespective of symptoms from all household members throughout the RSV season of 2009–2010 and tested for RSV using molecular techniques. Results. From 451 participants in 44 households a total of 15 396 nasopharyngeal swab samples were samples were collected, representing 86% of planned sampling. RSV was detected in 37 households (84%) and 173 participants (38%) and 28 study infants (64%). The infants acquired infection from within (15 infants; 54%) or outside (9 infants; 32%) the household; in 4 households the source of infant infection was inconclusive. Older children were index case patients for 11 (73%) of the within-household infant infections, and 10 of these 11 children were attending school. Conclusion. We demonstrate that school-going siblings frequently introduce RSV into households, leading to infection in infants.
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Turner P, Turner C, Watthanaworawit W, Carrara V, Cicelia N, Deglise C, Phares C, Ortega L, Nosten F. Respiratory virus surveillance in hospitalised pneumonia patients on the Thailand-Myanmar border. BMC Infect Dis 2013; 13:434. [PMID: 24498873 PMCID: PMC3847692 DOI: 10.1186/1471-2334-13-434] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 08/30/2013] [Indexed: 11/24/2022] Open
Abstract
Background Pneumonia is a significant cause of morbidity and mortality in the developing world. Viruses contribute significantly to pneumonia burden, although data for low-income and tropical countries are scarce. The aim of this laboratory-enhanced, hospital-based surveillance was to characterise the epidemiology of respiratory virus infections among refugees living on the Thailand-Myanmar border. Methods Maela camp provides shelter for ~45,000 refugees. Inside the camp, a humanitarian organisation provides free hospital care in a 158-bed inpatient department (IPD). Between 1st April 2009 and 30th September 2011, all patients admitted to the IPD with a clinical diagnosis of pneumonia were invited to participate. Clinical symptoms and signs were recorded and a nasopharyngeal aspirate (NPA) collected. NPAs were tested for adenoviruses, human metapneumovirus (hMPV), influenza A & B, and RSV by PCR. Results Seven hundred eight patient episodes (698 patients) diagnosed as pneumonia during the enhanced surveillance period were included in this analysis. The median patient age was 1 year (range: < 1-70), and 90.4% were aged < 5 years. At least one virus was detected in 53.7% (380/708) of episodes. Virus detection was more common in children aged < 5 years old (<1 year: OR 2.0, 95% CI 1.2-3.4, p = 0.01; 1-4 years: OR 1.4, 95% CI 0.8-2.3, p = 0.2). RSV was detected in 176/708 (24.9%); an adenovirus in 133/708 (18.8%); an influenza virus in 68/708 (9.6%); and hMPV in 33/708 (4.7%). Twenty-eight episodes of multiple viral infections were identified, most commonly adenovirus plus another virus. RSV was more likely to be detected in children <5 years (OR 12.3, 95% CI 3.0-50.8, p = 0.001) and influenza viruses in patients ≥5 years (OR 2.8, 95% CI 1.5-5.4, p = 0.002). IPD treatment was documented in 702/708 cases; all but one patient received antimicrobials, most commonly a beta-lactam (amoxicillin/ampicillin +/−gentamicin in 664/701, 94.7%). Conclusions Viral nucleic acid was identified in the nasopharynx in half the patients admitted with clinically diagnosed pneumonia. Development of immunisations targeting common respiratory viruses is likely to reduce the incidence of pneumonia in children living refugee camps and similar settings.
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Affiliation(s)
- Paul Turner
- Shoklo Malaria Research Unit, Mae Sot, Thailand.
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Jorquera PA, Choi Y, Oakley KE, Powell TJ, Boyd JG, Palath N, Haynes LM, Anderson LJ, Tripp RA. Nanoparticle vaccines encompassing the respiratory syncytial virus (RSV) G protein CX3C chemokine motif induce robust immunity protecting from challenge and disease. PLoS One 2013; 8:e74905. [PMID: 24040360 PMCID: PMC3769300 DOI: 10.1371/journal.pone.0074905] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 08/06/2013] [Indexed: 01/03/2023] Open
Abstract
Nanoparticle vaccines were produced using layer-by-layer fabrication and incorporating respiratory syncytial virus (RSV) G protein polypeptides comprising the CX3C chemokine motif. BALB/c mice immunized with G protein nanoparticle vaccines produced a neutralizing antibody response that inhibited RSV replication in the lungs following RSV challenge. ELISPOT analysis showed that G nanoparticle vaccinated mice had increased levels of RSV G protein-specific IL-4 and IFN-γ secreting cells compared to controls following RSV challenge. Remarkably, RSV challenge of G protein nanoparticle vaccinated mice resulted in increased RSV M2-specific IL-4 and IFN-γ secreting T cells, and increased M2-specific H-2Kd-tetramer positive CD8+ T cells in the lungs compared to controls. Cell type analysis showed vaccination was not associated with increased pulmonary eosinophilia following RSV challenge. These results demonstrate that vaccination of mice with the RSV G protein nanoparticle vaccines induces a potent neutralizing antibody response, increased G protein- and M2- specific T cell responses, and a reduction in RSV disease pathogenesis.
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Affiliation(s)
- Patricia A. Jorquera
- Department of Infectious Disease, University of Georgia, Athens, Georgia, United States of America
| | - Youngjoo Choi
- Department of Infectious Disease, University of Georgia, Athens, Georgia, United States of America
| | - Katie E. Oakley
- Department of Infectious Disease, University of Georgia, Athens, Georgia, United States of America
| | - Thomas J. Powell
- Artificial Cell Technologies, New Haven, Connecticut, United States of America
| | - James G. Boyd
- Artificial Cell Technologies, New Haven, Connecticut, United States of America
| | - Naveen Palath
- Artificial Cell Technologies, New Haven, Connecticut, United States of America
| | - Lia M. Haynes
- Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Larry J. Anderson
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Ralph A. Tripp
- Department of Infectious Disease, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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Sun Z, Pan Y, Jiang S, Lu L. Respiratory syncytial virus entry inhibitors targeting the F protein. Viruses 2013; 5:211-25. [PMID: 23325327 PMCID: PMC3564118 DOI: 10.3390/v5010211] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 12/17/2012] [Accepted: 01/11/2013] [Indexed: 11/16/2022] Open
Abstract
Human respiratory syncytial virus (RSV) is the main viral cause of respiratory tract infection in infants as well as some elderly and high-risk adults with chronic pulmonary disease and the severely immunocompromised. So far, no specific anti-RSV therapeutics or effective anti-RSV vaccines have been reported. Only one humanized monoclonal antibody, Palivizumab, has been approved for use in high-risk infants to prevent RSV infection. Ribavirin is the only drug licensed for therapy of RSV infection, but its clinical use is limited by its nonspecific anti-RSV activity, toxic effect, and relatively high cost. Therefore, development of novel effective anti-RSV therapeutics is urgently needed. The RSV envelope glycoprotein F plays an important role in RSV fusion with, and entry into, the host cell and, consequently, serves as an attractive target for developing RSV entry inhibitors. This article reviews advances made in studies of the structure and function of the F protein and the development of RSV entry inhibitors targeting it.
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Affiliation(s)
- Zhiwu Sun
- Key Laboratory of Medical Molecular Virology of Ministries of Education & Health, Shanghai Medical College and Institute of Medical Microbiology, Fudan University, Shanghai 200032, China; E-Mails: (Z.S.); (S.J.)
| | - Yanbin Pan
- Aris (Nantong) Pharmaceuticals Co. Ltd., Nantong Economic and Technological Area, Jiangsu Province 226006, China; E-Mail:
| | - Shibo Jiang
- Key Laboratory of Medical Molecular Virology of Ministries of Education & Health, Shanghai Medical College and Institute of Medical Microbiology, Fudan University, Shanghai 200032, China; E-Mails: (Z.S.); (S.J.)
| | - Lu Lu
- Key Laboratory of Medical Molecular Virology of Ministries of Education & Health, Shanghai Medical College and Institute of Medical Microbiology, Fudan University, Shanghai 200032, China; E-Mails: (Z.S.); (S.J.)
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Turner C, Turner P, Cararra V, Eh Lwe N, Watthanaworawit W, Day NP, White NJ, Goldblatt D, Nosten F. A high burden of respiratory syncytial virus associated pneumonia in children less than two years of age in a South East Asian refugee population. PLoS One 2012. [PMID: 23185545 PMCID: PMC3502361 DOI: 10.1371/journal.pone.0050100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Background Pneumonia is a major cause of childhood mortality and morbidity approximately 1.6 million deaths and 150 million episodes occur annually in children <5 years. Respiratory syncytial virus (RSV) may be responsible for up to 25% of cases and 12% of deaths making it an important potential vaccine target, although data from South East Asia is scarce. Methods We followed a birth cohort of Burmese refugee children, born over a one year period, for two years. Pneumonia episodes were diagnosed using WHO criteria. A chest radiograph, nasopharyngeal aspirate and non-specific markers of infection were taken during each episode. Results The incidence of RSV-associated pneumonia was 0.24 (95% CI 0.22–0.26) episodes per child year. All children with pneumonia received antibiotic treatment, following WHO guidelines. The highest incidence was in the 2–12 month age group. The commonest diagnosis in a child with RSV-associated pneumonia was non-severe pneumonia (239/362∶66.0%), however the incidence of RSV-associated severe or very severe pneumonia was 0.08 (95% CI 0.01–0.10) episodes per child year. Birth in the wet season increased the risk of severe disease in children who had their first episode of RSV-associated pneumonia aged 2–11 months (OR 28.7, 95% CI 6.6–125.0, p<0.001). RSV episodes were highly seasonal being responsible for 80.0% of all the pneumonia episodes occurring each October and November over the study period. Conclusions There was a high incidence of RSV associated pneumonia in this refugee population. Interventions to prevent RSV infection have the potential to reduce the incidence of clinically diagnosed pneumonia and hence unnecessary antibiotic usage in this population.
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Labro MT. Immunomodulatory effects of antimicrobial agents. Part I: antibacterial and antiviral agents. Expert Rev Anti Infect Ther 2012; 10:319-40. [PMID: 22397566 DOI: 10.1586/eri.12.11] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Despite impressive therapeutic progresses in the battle against infections, microorganisms are still a threat to mankind. With hundreds of antibacterial molecules, major concerns remain about the emergence of resistant and multidrug-resistant pathogens. On the other hand, the antiviral drug armamentarium is comprised of only a few dozens of compounds which are highly pathogen specific, and resistance is also a concern. According to Arturo Casadevall (Albert Einstein College of Medicine, NY, USA), we have now entered the third era of anti-infective strategy, which intends to favor the interplay between active molecules and the immune system. The first part of this review focuses on the potential immunomodulating properties of anti-infective agents, beginning with antibacterial and antiviral agents.
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Affiliation(s)
- Marie-Thérèse Labro
- Inserm SC14 Centre d'Expertise Collective, Université Paris Diderot Paris, 7 Faculté de Médecine Site Bichat, 16 rue Henri Huchard, 75890, Paris Cedex 18, France.
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17
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Whole genome sequencing and evolutionary analysis of human respiratory syncytial virus A and B from Milwaukee, WI 1998-2010. PLoS One 2011; 6:e25468. [PMID: 21998661 PMCID: PMC3188560 DOI: 10.1371/journal.pone.0025468] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 09/05/2011] [Indexed: 01/24/2023] Open
Abstract
Background Respiratory Syncytial Virus (RSV) is the leading cause of lower respiratory-tract infections in infants and young children worldwide. Despite this, only six complete genome sequences of original strains have been previously published, the most recent of which dates back 35 and 26 years for RSV group A and group B respectively. Methodology/Principal Findings We present a semi-automated sequencing method allowing for the sequencing of four RSV whole genomes simultaneously. We were able to sequence the complete coding sequences of 13 RSV A and 4 RSV B strains from Milwaukee collected from 1998–2010. Another 12 RSV A and 5 RSV B strains sequenced in this study cover the majority of the genome. All RSV A and RSV B sequences were analyzed by neighbor-joining, maximum parsimony and Bayesian phylogeny methods. Genetic diversity was high among RSV A viruses in Milwaukee including the circulation of multiple genotypes (GA1, GA2, GA5, GA7) with GA2 persisting throughout the 13 years of the study. However, RSV B genomes showed little variation with all belonging to the BA genotype. For RSV A, the same evolutionary patterns and clades were seen consistently across the whole genome including all intergenic, coding, and non-coding regions sequences. Conclusions/Significance The sequencing strategy presented in this work allows for RSV A and B genomes to be sequenced simultaneously in two working days and with a low cost. We have significantly increased the amount of genomic data that is available for both RSV A and B, providing the basic molecular characteristics of RSV strains circulating in Milwaukee over the last 13 years. This information can be used for comparative analysis with strains circulating in other communities around the world which should also help with the development of new strategies for control of RSV, specifically vaccine development and improvement of RSV diagnostics.
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Munday DC, Hiscox JA, Barr JN. Quantitative proteomic analysis of A549 cells infected with human respiratory syncytial virus subgroup B using SILAC coupled to LC-MS/MS. Proteomics 2011; 10:4320-34. [PMID: 21110324 PMCID: PMC7167978 DOI: 10.1002/pmic.201000228] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Human respiratory syncytial virus (HRSV) is a leading cause of serious lower respiratory tract infections in infants. The virus has two subgroups A and B, which differ in prevalence and (nucleotide) sequence. The interaction of subgroup A viruses with the host cell is relatively well characterized, whereas for subgroup B viruses it is not. Therefore quantitative proteomics was used to investigate the interaction of subgroup B viruses with A549 cells, a respiratory cell line. Changes in the cellular proteome and potential canonical pathways were determined using SILAC coupled to LC‐MS/MS and Ingenuity Pathway Analysis. To reduce sample complexity and investigate potential trafficking both nuclear and cytoplasmic fractions were analyzed. A total of 904 cellular and six viral proteins were identified and quantified, of which 112 cellular proteins showed a twofold or more change in HRSV‐infected cells. Data sets were validated using indirect immunofluorescence confocal microscopy on independent samples. Major changes were observed in constituents of mitochondria including components of the electron transport chain complexes and channels, as well as increases in the abundance of the products of interferon‐stimulated genes. This is the first quantitative proteomic analysis of cells infected with HRSV‐subgroup B.
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Affiliation(s)
- Diane C Munday
- Institute of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
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20
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Han J, Jia Y, Takeda K, Shiraishi Y, Okamoto M, Dakhama A, Gelfand EW. Montelukast during primary infection prevents airway hyperresponsiveness and inflammation after reinfection with respiratory syncytial virus. Am J Respir Crit Care Med 2010; 182:455-63. [PMID: 20442434 PMCID: PMC2937239 DOI: 10.1164/rccm.200912-1811oc] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Accepted: 04/28/2010] [Indexed: 12/20/2022] Open
Abstract
RATIONALE Respiratory syncytial virus (RSV) bronchiolitis in infants may be followed by the development of asthma-like symptoms. Age at first infection dictates consequences upon reinfection. Reinfection of mice initially exposed as neonates to RSV enhanced development of airway hyperresponsiveness (AHR), eosinophilic inflammation, and mucus hyperproduction. RSV lower respiratory tract disease is associated with activation of the leukotriene pathway. OBJECTIVES To determine the effects of montelukast (MK), a cysteinyl leukotriene (cysLT) receptor antagonist, in primary and secondary RSV-infected newborn and adult mice. METHODS BALB/c mice were infected with RSV at 1 week (neonate) or 6 to 8 weeks (adult) of age and reinfected 5 weeks later. MK was administered 1 day before the initial infection and through Day 6 after infection. Seven days after primary or secondary infection, airway function was assessed by lung resistance to increasing doses of inhaled methacholine; lung inflammation, goblet cell metaplasia, and cytokine levels in bronchoalveolar lavage fluid were monitored. MEASUREMENTS AND MAIN RESULTS RSV infection induced cysLT release in bronchoalveolar lavage fluid. MK decreased RSV-induced AHR, airway inflammation, and increased IFN-gamma production in primary infected adult and neonatal mice. MK, administered during initial infection of neonates but not during secondary infection, prevented subsequent enhancement of AHR, airway eosinophilia, and mucus hyperproduction upon reinfection. CONCLUSIONS MK attenuated the initial responses to primary RSV infection in both age groups and altered the consequences of RSV reinfection in mice initially infected as neonates. These data support an important role for cysLT in RSV-induced AHR and inflammation.
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Affiliation(s)
- Junyan Han
- Division of Cell Biology, Department of Pediatrics, National Jewish Health, Denver, Colorado
| | - Yi Jia
- Division of Cell Biology, Department of Pediatrics, National Jewish Health, Denver, Colorado
| | - Katsuyuki Takeda
- Division of Cell Biology, Department of Pediatrics, National Jewish Health, Denver, Colorado
| | - Yoshiki Shiraishi
- Division of Cell Biology, Department of Pediatrics, National Jewish Health, Denver, Colorado
| | - Masakazu Okamoto
- Division of Cell Biology, Department of Pediatrics, National Jewish Health, Denver, Colorado
| | - Azzeddine Dakhama
- Division of Cell Biology, Department of Pediatrics, National Jewish Health, Denver, Colorado
| | - Erwin W. Gelfand
- Division of Cell Biology, Department of Pediatrics, National Jewish Health, Denver, Colorado
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Berkley JA, Munywoki P, Ngama M, Kazungu S, Abwao J, Bett A, Lassauniére R, Kresfelder T, Cane PA, Venter M, Scott JAG, Nokes DJ. Viral etiology of severe pneumonia among Kenyan infants and children. JAMA 2010; 303:2051-7. [PMID: 20501927 PMCID: PMC2968755 DOI: 10.1001/jama.2010.675] [Citation(s) in RCA: 238] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
CONTEXT Pneumonia is the leading cause of childhood death in sub-Saharan Africa. Comparative estimates of the contribution of causative pathogens to the burden of disease are essential for targeted vaccine development. OBJECTIVE To determine the viral etiology of severe pneumonia among infants and children at a rural Kenyan hospital using comprehensive and sensitive molecular diagnostic techniques. DESIGN, SETTING, AND PARTICIPANTS Prospective observational and case-control study during 2007 in a rural Kenyan district hospital. Participants were children aged 1 day to 12 years, residing in a systematically enumerated catchment area, and who either were admitted to Kilifi District Hospital meeting World Health Organization clinical criteria for severe pneumonia or very severe pneumonia; (2) presented with mild upper respiratory tract infection but were not admitted; or (3) were well infants and children attending for immunization. MAIN OUTCOME MEASURES The presence of respiratory viruses and the odds ratio for admission with severe disease. RESULTS Of 922 eligible admitted patients, 759 were sampled (82% [median age, 9 months]). One or more respiratory viruses were detected in 425 of the 759 sampled (56% [95% confidence interval {CI}, 52%-60%]). Respiratory syncytial virus (RSV) was detected in 260 participants (34% [95% CI, 31%-38%]) and other respiratory viruses were detected in 219 participants (29%; 95% CI, 26%-32%), the most common being Human coronavirus 229E (n = 51 [6.7%]), influenza type A (n = 44 [5.8%]), Parainfluenza type 3 (n = 29 [3.8%]), Human adenovirus (n = 29 [3.8%]), and Human metapneumovirus (n = 23 [3.0%]). Compared with well control participants, detection of RSV was associated with severe disease (5% [corrected] in control participants; adjusted odds ratio, 6.11 [95% CI, 1.65-22.6]) while collectively, other respiratory viruses were not associated with severe disease (23% in control participants; adjusted odds ratio, 1.27 [95% CI, 0.64-2.52]). CONCLUSION In a sample of Kenyan infants and children admitted with severe pneumonia to a rural hospital, RSV was the predominant viral pathogen.
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Affiliation(s)
- James A Berkley
- Kenya Medical Research Institute, Centre for Geographic Medicine Research-Coast, Kilifi, Kenya.
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Anderson R, Huang Y, Langley JM. Prospects for defined epitope vaccines for respiratory syncytial virus. Future Microbiol 2010; 5:585-602. [DOI: 10.2217/fmb.10.22] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The history of vaccines for respiratory syncytial virus (RSV) illustrates the complex immunity and immunopathology to this ubiquitous virus, starting from the failed formalin-inactivated vaccine trials performed in the 1960s. An attractive alternative to traditional live or killed virus vaccines is a defined vaccine composed of discrete antigenic epitopes for which immunological activities have been characterized as comprehensively as possible. Here we present cumulative data on murine and human CD4, CD8 and neutralization epitopes identified in RSV proteins along with information regarding their associated immune responses and host-dependent variability. Identification and characterization of RSV epitopes is a rapidly expanding topic of research with potential contributions to the tailored design of improved safe and effective vaccines.
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Affiliation(s)
- Robert Anderson
- Department of Microbiology & Immunology, Pediatrics and Canadian Center for Vaccinology, Dalhousie University, Halifax, Nova Scotia, B3H 1X5, Canada
| | - Yan Huang
- Department of Microbiology & Immunology and Canadian Center for Vaccinology, Dalhousie University, Halifax, Nova Scotia, B3H 1X5, Canada
| | - Joanne M Langley
- Department of Pediatrics, Community Health & Epidemiology and Canadian Center for Vaccinology, Dalhousie University, Halifax, Nova Scotia, B3H 1X5, Canada
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Abstract
BACKGROUND Data on the contribution of specific infections to childhood deaths in developed countries are limited. METHODS Infection-related deaths in children aged 28 days to 14 years who died in England and Wales between 2003 and 2005 were identified from routine anonymized death certificate dataset provided by the Office for National Statistics to the Health Protection Agency, using predefined International Classification of Diseases codes for infection. RESULTS There were 1368 infection-related deaths documented, constituting 20% of all childhood deaths. An underlying medical condition was recorded in 50% (676 cases), the most common being prematurity in infants (322/660, 52%), cerebral palsy in 1 to 4 year olds (46/190, 24%), and malignancy (46/163, 28%) in 5 to 14 year olds. Of the 837 deaths where a pathogen was coded, 494 (59%) specified bacterial infection, 256 (31%) viral infection, and 69 (8%) fungal infection. Among deaths with recorded bacterial infections, a lower proportion of meningococcal and pneumococcal infections (14% [22/155] vs. 60% [205/339], P < 0.0001) and a higher proportion of Gram-negative enteric bacilli (78/155 cases [50%] vs. 17/339 cases [5%], P < 0.0001) were reported in children with and without documented underlying medical conditions, respectively. CONCLUSIONS Infections continue to make a major contribution to deaths in children, particularly among those with underlying conditions. Identification of the pathogens associated with childhood deaths should help prioritize the development of intervention strategies for reducing pediatric mortality. Linkage of death registrations to national infectious disease surveillance systems should be undertaken to strengthen monitoring of infectious deaths and evaluate the effect of interventions.
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Abstract
Viral infections, including beta-herpes viruses and community respiratory viruses, are frequent pathogens in lung transplant recipients. These pathogens have become increasingly recognized as having a significant role in long-term outcomes of lung transplantation, which has been limited by the frequent development of infections, and chronic allograft dysfunction. Community respiratory viruses, such as influenza and respiratory syncytial virus have been associated with both acute rejection and chronic allograft dysfunction, particularly if early treatment was not administered. beta-herpes viruses, particularly cytomegalovirus (CMV), have long been associated with increased mortality in lung transplant recipients, although the advent of effective antiviral strategies has led to improved morbidity and mortality. Because these pathogens have been associated with altered immune responses against the allograft, a better understanding of immunopathogenesis of viral infections may lead to a broader approach to limit the morbidity from these pathogens.
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Affiliation(s)
- Pali Dedhiya Shah
- Division of Pulmonary and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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25
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Principi N, Esposito S. Antigen-based assays for the identification of influenza virus and respiratory syncytial virus: why and how to use them in pediatric practice. Clin Lab Med 2010; 29:649-60. [PMID: 19892226 DOI: 10.1016/j.cll.2009.07.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This article describes the clinical and socioeconomic relevance of influenza (IV) and respiratory syncytial virus (RSV) in pediatrics, the characteristics and limitations of currently available assays, and the impact of rapid diagnostic tests. This article shows that rapid tests for the detection and identification of IV and RSV in the respiratory secretions of infants and children are useful in the diagnosis of common, and possibly severe diseases, such as influenza and bronchiolitis. The tests' specificity and sensitivity make them most reliable when the prevalence of influenza or RSV infection is high, which suggests that their routine use should be restricted to the peak periods of viral circulation. The most recently marketed tests are similarly effective in identifying viruses, and so pediatricians should choose those that are less expensive, less time consuming, and easier to perform and to interpret.
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Affiliation(s)
- Nicola Principi
- Department of Maternal and Pediatric Sciences, University of Milan, Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, 20122 Milano, Italy.
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Georgiev VS. Pneumonia Virus of Mice (PVM): Exploring Novel Therapeutic Options In a Severe Respiratory Disease Model. NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES, NIH 2010. [PMCID: PMC7176177 DOI: 10.1007/978-1-60761-512-5_35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Respiratory syncytial virus (RSV) is the most important respiratory pathogen among infants and toddlers, with infections prevalent and nearly universal in this age group. Severe infections are more common among premature infants, those with cardiac and pulmonary anomalies, and the immunosupressed. Effective prophylactic monoclonal antibody treatment is available for high-risk infants, but there is no effective vaccine. Mouse challenge models have been used for the study of the human RSV pathogen, but the most severe forms of RSV disease are not replicated by this approach. Pneumonia virus of mice (PVM; family Paramyxoviridae, genus Pneumovirus) is a mouse pathogen of the same family as human respiratory syncytial virus. PVM replicates efficiently in mouse-lung epithelial cells in vivo in response to a minimal virus inoculum, and replication is accompanied by local production of proinflammatory cytokines (MIP-1α, MIP-2, MCP-1, and IFN-γ) and granulocyte recruitment to the lung. PVM infection and the ensuing inflammatory response can lead to pulmonary edema and respiratory compromise. Our laboratories have pioneered the use of the PVM model for the study of human clinical disease, which has provided important insights into the role of the inflammatory response in the pathogenesis of severe respiratory virus infection. As part of this work, we have presented several immunomodulatory strategies that clearly reduce morbidity and mortality when administered to PVM infected, symptomatic mice, and thus hold promise as realistic therapeutic strategies for severe RSV infection in human subjects.
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Affiliation(s)
- Vassil St. Georgiev
- Dept. Health & Human Services, National Institute of Health, Rockledge Drive 6610, Bethesda, 20892 Maryland USA
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Bem RA, van Woensel JBM, Lutter R, Domachowske JB, Medema JP, Rosenberg HF, Bos AP. Granzyme A- and B-cluster deficiency delays acute lung injury in pneumovirus-infected mice. THE JOURNAL OF IMMUNOLOGY 2009; 184:931-8. [PMID: 20018616 DOI: 10.4049/jimmunol.0903029] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Lower respiratory tract infection by the human pneumovirus respiratory syncytial virus is a frequent cause of acute lung injury in children. Severe pneumovirus disease in humans is associated with activation of the granzyme pathway by effector lymphocytes, which may promote pathology by exaggerating proapoptotic caspase activity and proinflammatory activity. The main goal of this study was to determine whether granzymes contribute to the development of acute lung injury in pneumovirus-infected mice. Granzyme-expressing mice and granzyme A- and B-cluster single- and double-knockout mice were inoculated with the rodent pneumovirus pneumonia virus of mice strain J3666, and were studied for markers of lung inflammation and injury. Expression of granzyme A and B is detected in effector lymphocytes in mouse lungs in response to pneumovirus infection. Mice deficient for granzyme A and the granzyme B cluster have unchanged virus titers in the lungs but show a significantly delayed clinical response to fatal pneumovirus infection, a feature that is associated with delayed neutrophil recruitment, diminished activation of caspase-3, and reduced lung permeability. We conclude that granzyme A- and B-cluster deficiency delays the acute progression of pneumovirus disease by reducing alveolar injury.
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Affiliation(s)
- Reinout A Bem
- Pediatric Intensive Care Unit, Emma Children's Hospital, Academic Medical Center, Amsterdam, The Netherlands.
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Vaccination to induce antibodies blocking the CX3C-CX3CR1 interaction of respiratory syncytial virus G protein reduces pulmonary inflammation and virus replication in mice. J Virol 2009; 84:1148-57. [PMID: 19864390 DOI: 10.1128/jvi.01755-09] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Respiratory syncytial virus (RSV) infection causes substantial morbidity and some deaths in the young and elderly worldwide. There is no safe and effective vaccine available, although it is possible to reduce the hospitalization rate for high-risk children by anti-RSV antibody prophylaxis. RSV has been shown to modify the immune response to infection, a feature linked in part to RSV G protein CX3C chemokine mimicry. This study determined if vaccination with G protein polypeptides or peptides spanning the central conserved region of the G protein could induce antibodies that blocked G protein CX3C-CX3CR1 interaction and disease pathogenesis mediated by RSV infection. The results show that mice vaccinated with G protein peptides or polypeptides containing the CX3C motif generate antibodies that inhibit G protein CX3C-CX3CR1 binding and chemotaxis, reduce lung virus titers, and prevent body weight loss and pulmonary inflammation. The results suggest that RSV vaccines that induce antibodies that block G protein CX3C-CX3CR1 interaction may offer a new, safe, and efficacious RSV vaccine strategy.
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Mao H, Chattopadhyay S, Banerjee AK. N-terminally truncated C protein, CNDelta25, of human parainfluenza virus type 3 is a potent inhibitor of viral replication. Virology 2009; 394:143-8. [PMID: 19747707 DOI: 10.1016/j.virol.2009.08.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Revised: 07/06/2009] [Accepted: 08/18/2009] [Indexed: 11/27/2022]
Abstract
The C protein of human parainfluenza virus type 3 (HPIV3) is a multifunctional accessory protein that inhibits viral transcription and interferon (IFN) signaling. In the present study, we found that removal of N-terminal 25 or 50 amino acid residues from the C protein (CNDelta25 or CNDelta50) totally abolished viral RNA synthesis in the HPIV3 minigenome system. Further N-terminal or C-terminal deletion impaired the inhibitory ability of CNDelta25 and CNDelta50. Subsequent mutagenesis analysis suggested that the N-terminal-charged amino acid residues (K3, K6, K12, E16, and R24) contribute to the higher inhibition caused by CNDelta25 than the C protein. Consistent with viral RNA synthesis inhibition, the growth of HPIV3 was significantly decreased by 5 logs in HeLa-derived cell line expressing CNDelta25. Interestingly, replication of respiratory syncytial virus (RSV), another important respiratory tract pathogen, was also strongly inhibited in the presence of CNDelta25. These findings provide a promising potential to use CNDelta25 as an antiviral agent against the clinically important respiratory tract diseases caused by HPIV3 and RSV.
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Affiliation(s)
- Hongxia Mao
- Virology Section, Department of Molecular Genetics, Lerner Research Institute, Cleveland Clinic Foundation, NN1-06, 9500 Euclid Avenue, Cleveland, OH 44195, USA
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Respiratory syncytial virus nonstructural proteins decrease levels of multiple members of the cellular interferon pathways. J Virol 2009; 83:9682-93. [PMID: 19625398 DOI: 10.1128/jvi.00715-09] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Viruses of the Paramyxoviridae family, such as the respiratory syncytial virus (RSV), suppress cellular innate immunity represented by type I interferon (IFN) for optimal growth in their hosts. The two unique nonstructural (NS) proteins, NS1 and NS2, of RSV suppress IFN synthesis, as well as IFN function, but their exact targets are still uncharacterized. Here, we investigate if either or both of the NS proteins affect the steady-state levels of key members of the IFN pathway. We found that both NS1 and NS2 decreased the levels of TRAF3, a strategic integrator of multiple IFN-inducing signals, although NS1 was more efficient. Only NS1 reduced IKKepsilon, a key protein kinase that specifically phosphorylates and activates IFN regulatory factor 3. Loss of the TRAF3 and IKKepsilon proteins appeared to involve a nonproteasomal mechanism. Interestingly, NS2 modestly increased IKKepsilon levels. In the IFN response pathway, NS2 decreased the levels of STAT2, the essential transcription factor for IFN-inducible antiviral genes. Preliminary mapping revealed that the C-terminal 10 residues of NS1 were essential for reducing IKKepsilon levels and the C-terminal 10 residues of NS2 were essential for increasing and reducing IKKepsilon and STAT2, respectively. In contrast, deletion of up to 20 residues of the C termini of NS1 and NS2 did not diminish their TRAF3-reducing activity. Coimmunoprecipitation studies revealed that NS1 and NS2 form a heterodimer. Clearly, the NS proteins of RSV, working individually and together, regulate key signaling molecules of both the IFN activation and response pathways.
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