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2.
Wellcome Open Res ; 8: 73, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875805

RESUMO

Waiting is at the centre of experiences and practices of healthcare. However, we know very little about the relationship between the subjective experiences of patients who wait in and for care, health practitioners who 'prescribe' and manage waiting, and how this relates to broader cultural meanings of waiting. Waiting features heavily in the sociological, managerial, historical and health economics literatures that investigate UK healthcare, but the focus has been on service provision and quality, with waiting (including waiting lists and waiting times) drawn on as a key marker to test the efficiency and affordability of the NHS. In this article, we consider the historical contours of this framing of waiting, and ask what has been lost or occluded through its development. To do so, we review the available discourses in the existing literature on the NHS through a series of 'snapshots' or key moments in its history. Through its negative imprint, we argue that what shadows these discourses is the idea of waiting and care as phenomenological temporal experiences, and time as a practice of care. In response, we begin to trace the intellectual and historical resources available for alternative histories of waiting - materials that might enable scholars to reconstruct some of the complex temporalities of care marginalized in existing accounts of waiting, and which could help reframe both future historical accounts and contemporary debates about waiting in the NHS.

3.
J Infect Dis ; 227(1): 50-60, 2022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-36281651

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is a leading viral respiratory pathogen in infants. The objective of this study was to generate RSV live-attenuated vaccine (LAV) candidates by removing the G-protein mucin domains to attenuate viral replication while retaining immunogenicity through deshielding of surface epitopes. METHODS: Two LAV candidates were generated from recombinant RSV A2-line19F by deletion of the G-protein mucin domains (A2-line19F-G155) or deletion of the G-protein mucin and transmembrane domains (A2-line19F-G155S). Vaccine attenuation was measured in BALB/c mouse lungs by fluorescent focus unit (FFU) assays and real-time polymerase chain reaction (RT-PCR). Immunogenicity was determined by measuring serum binding and neutralizing antibodies in mice following prime/boost on days 28 and 59. Efficacy was determined by measuring RSV lung viral loads on day 4 postchallenge. RESULTS: Both LAVs were undetectable in mouse lungs by FFU assay and elicited similar neutralizing antibody titers compared to A2-line19F on days 28 and 59. Following RSV challenge, vaccinated mice showed no detectable RSV in the lungs by FFU assay and a significant reduction in RSV RNA in the lungs by RT-PCR of 560-fold for A2-line19F-G155 and 604-fold for A2-line19F-G155S compared to RSV-challenged, unvaccinated mice. CONCLUSIONS: Removal of the G-protein mucin domains produced RSV LAV candidates that were highly attenuated with retained immunogenicity.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano , Animais , Camundongos , Vacinas Atenuadas , Mucinas , Camundongos Endogâmicos BALB C , Vírus Sincicial Respiratório Humano/genética , Anticorpos Neutralizantes , Proteínas de Ligação ao GTP , Anticorpos Antivirais , Proteínas Virais de Fusão/genética
4.
NPJ Vaccines ; 7(1): 85, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906244

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the COVID-19 global pandemic. SARS-CoV-2 is an enveloped RNA virus that relies on its trimeric surface glycoprotein spike for entry into host cells. Here we describe the COVID-19 vaccine candidate MV-014-212, a live, attenuated, recombinant human respiratory syncytial virus expressing a chimeric SARS-CoV-2 spike as the only viral envelope protein. MV-014-212 was attenuated and immunogenic in African green monkeys (AGMs). One mucosal administration of MV-014-212 in AGMs protected against SARS-CoV-2 challenge, reducing by more than 200-fold the peak shedding of SARS-CoV-2 in the nose. MV-014-212 elicited mucosal immunoglobulin A in the nose and neutralizing antibodies in serum that exhibited cross-neutralization against virus variants of concern Alpha, Beta, and Delta. Intranasally delivered, live attenuated vaccines such as MV-014-212 entail low-cost manufacturing suitable for global deployment. MV-014-212 is currently in Phase 1 clinical trials as an intranasal COVID-19 vaccine.

5.
ACS Biomater Sci Eng ; 8(2): 493-501, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35030308

RESUMO

Enzymatic decontamination of organophosphate compounds offers a biofriendly pathway to the neutralization of highly dangerous compounds. Environmental dissemination of enzymes, however, is an ongoing problem considering the costly process of production and chemical modification for stability that can diminish catalytic activity. As a result, there is interest in the potential for enzymatic encapsulation in situ or into nascent bacterial membrane vesicles to improve catalytic stability across various environmental challenges associated with storage and field deployment. In this study, we have engineered bacterial outer membrane vesicles (OMVs) to encapsulate the diisopropyl fluorophosphatase (DFPase), an enzyme originally isolated from squid Loligo vulgaris and capable of hydrolyzing diisopropyl fluorophosphate (DFP) and other organophosphates compounds. Here we employed a recombinant lipopeptide anchor to direct recruitment of DFPase into OMVs, which were isolated from culture media and tested for catalytic activity against both diisopropyl fluorophosphate and paraoxon. Our encapsulation strategy prevented the loss of catalytic activity despite lyophilization, extended storage time (2 days), and extreme temperatures up to 80 °C. These data underscore the appeal of DFPase as a biodecontaminant of organophosphates as well as the potential for OMV packaging in stabilized field deployment applications.


Assuntos
Loligo , Hidrolases de Triester Fosfórico , Animais , Membrana Externa Bacteriana , Loligo/metabolismo , Hidrolases de Triester Fosfórico/química , Hidrolases de Triester Fosfórico/metabolismo , Temperatura
6.
Lancet Planet Health ; 5(4): e230-e236, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33838738

RESUMO

COVID-19 is a sign of a global malaise. The pandemic is an outcome of what we term a planetary dysbiosis, for which underlining drivers include inequality and the exploitation and extraction of human and non-human labours. The implication is that the usual fixes to outbreaks of infectious diseases (ie, surveillance, pharmaceutical measures, and non-pharmaceutical measures) will be insufficient without a thorough reappraisal of and investment in planetary health. Given the heterogeneity and diversity of environments and populations, we envisage these actions as a matter for the generation of new kinds of public, requiring widespread and multiple forms of engagement to generate lasting solutions. We use and extend the concept of healthy publics to suggest a movement that can start to reclaim planetary health as a collective and ongoing issue.


Assuntos
Surtos de Doenças/prevenção & controle , Meio Ambiente , Saúde Global , Saúde Única , Saúde Pública , Mudança Social , Determinantes Sociais da Saúde , Animais , COVID-19/prevenção & controle , Gerenciamento Clínico , Humanos , Cooperação Internacional , SARS-CoV-2
7.
J Am Chem Soc ; 143(10): 4005-4016, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33673734

RESUMO

Melanin is a ubiquitous natural pigment found in a diverse array of organisms. Allomelanin is a class of nitrogen-free melanin often found in fungi. Herein, we find artificial allomelanin analogues exhibit high intrinsic microporosity and describe an approach for further increasing and tuning that porosity. Notably, the synthetic method involves an oxidative polymerization of 1,8-DHN in water, negating the need for multiple complex templating steps and avoiding expensive or complex chemical precursors. The well-defined morphologies of these nanomaterials were elucidated by a combination of electron microscopy and scattering methods, yielding to high-resolution 3D reconstruction based on small-angle X-ray scattering (SAXS) results. Synthetic allomelanin nanoparticles exhibit high BET areas, up to 860 m2/g, and are capable of ammonia capture up to 17.0 mmol/g at 1 bar. In addition, these nanomaterials can adsorb nerve agent simulants in solution and as a coating on fabrics with high breathability where they prevent breakthrough. We also confirmed that naturally derived fungal melanin can adsorb nerve gas simulants in solution efficiently despite lower porosity than synthetic analogues. Our approach inspires further analysis of yet to be discovered biological materials of this class where melanins with intrinsic microporosity may be linked to evolutionary advantages in relevant organisms and may in turn inspire the design of new high surface area materials.


Assuntos
Biopolímeros/química , Melaninas/química , Adsorção , Biopolímeros/metabolismo , Fungos/metabolismo , Melaninas/metabolismo , Nanopartículas/química , Naftóis/química , Naftóis/metabolismo , Paraoxon/química , Paraoxon/metabolismo , Porosidade , Espalhamento a Baixo Ângulo , Difração de Raios X
8.
J Am Chem Soc ; 143(8): 3094-3103, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33600146

RESUMO

Commonly known as a skin pigment, melanin has a vital role in UV radiation protection, primarily acting as a radical scavenger. However, a lesser known natural property of melanin, observed in some melanized organisms, is its capacity to adsorb toxins, including metals and organic molecules. Inspired by this, we set out to generate a synthetic porous melanin that would pave the way to enhancing the natural adsorbent properties of melanin and melanin-like materials. Here, we developed a method for the synthesis of porous polydopamine-based melanin utilizing a mesoporous silica (MS) nanoparticle template and characterized its physical properties. Through the oxidative polymerization of dopamine, followed by the etching of silica, we generated synthetic porous melanin (SPM) with the highest measured surface area of any known polydopamine-based material. The prepared SPM was effective for the uptake of various gases and organophosphate toxins, with the material exhibiting high selectivity for CO2 over CH4 and high potential for ammonia capture. Given the demonstrated advantages provided by synthetic porous melanin and melanin's role as an adsorbent in nature, we anticipate the discovery of porous analogues in biological systems.


Assuntos
Melaninas/química , Melaninas/síntese química , Dióxido de Carbono/química , Indóis/química , Metano/química , Polímeros/química , Porosidade
10.
Adv Healthc Mater ; 10(4): e2000714, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32755047

RESUMO

Respiratory syncytial virus (RSV), for which there is currently no licensed vaccine, displays a fusion (F) protein that is considered a vaccine target. This protein has an antigenic site called site Ø, which has been shown to elicit potent, neutralizing antibodies and has therefore been considered important in the formulation of RSV vaccines. However, this site is also the least conserved region on the F protein across RSV subtypes. Therefore, directing the immune response away from site Ø and refocusing it toward more conserved parts of the RSV F protein might serve to better elicit broadly neutralizing antibodies. To demonstrate that directing the immune response away from site Ø is a viable approach, a prefusion F-based vaccine based on an F protein with a shielded site Ø is generated. Sera from mice immunized with multivalent scaffolds presenting this immunogen is capable of neutralizing RSV of both subtypes. This result may have application in the development of an effective and broadly protective RSV vaccine.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano , Animais , Anticorpos Antivirais , Camundongos , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Proteínas Virais de Fusão/genética
11.
J Virol ; 95(2)2020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-33115881

RESUMO

This study identified a genotype of respiratory syncytial virus (RSV) associated with increased acute respiratory disease severity in a cohort of previously healthy term infants. The genotype (2stop+A4G) consists of two components. The A4G component is a prevalent point mutation in the 4th position of the gene end transcription termination signal of the G gene of currently circulating RSV strains. The 2stop component is two tandem stop codons at the G gene terminus, preceding the gene end transcription termination signal. To investigate the biological role of these RSV G gene mutations, recombinant RSV strains harboring either a wild-type A2 strain G gene (one stop codon preceding a wild-type gene end signal), an A4G gene end signal preceded by one stop codon, or the 2stop+A4G virulence-associated combination were generated and characterized. Infection with the recombinant A4G (rA4G) RSV mutant resulted in transcriptional readthrough and lower G and fusion (F) protein levels than for the wild type. Addition of a second stop codon preceding the A4G point mutation (2stop+A4G) restored G protein expression but retained lower F protein levels. These data suggest that RSV G and F glycoprotein expression is regulated by transcriptional and translational readthrough. Notably, while rA4G and r2stop+A4G RSV were attenuated in cells and in naive BALB/c mice compared to that for wild-type RSV, the r2stop+A4G RSV was better able to infect BALB/c mice in the presence of preexisting immunity than rA4G RSV. Together, these factors may contribute to the maintenance and virulence of the 2stop+A4G genotype in currently circulating RSV-A strains.IMPORTANCE Strain-specific differences in respiratory syncytial virus (RSV) isolates are associated with differential pathogenesis in mice. However, the role of RSV genotypes in human infection is incompletely understood. This work demonstrates that one such genotype, 2stop+A4G, present in the RSV attachment (G) gene terminus is associated with greater infant disease severity. The genotype consists of two tandem stop codons preceding an A-to-G point mutation in the 4th position of the G gene end transcription termination signal. Virologically, the 2stop+A4G RSV genotype results in reduced levels of the RSV fusion (F) glycoprotein. A recombinant 2stop+A4G RSV was better able to establish infection in the presence of existing RSV immunity than a virus harboring the common A4G mutation. These data suggest that regulation of G and F expression has implications for virulence and, potentially, immune evasion.


Assuntos
Evasão da Resposta Imune/genética , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/patogenicidade , Proteínas Virais de Fusão/genética , Animais , Linhagem Celular , Regulação Viral da Expressão Gênica , Genótipo , Humanos , Lactente , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Filogenia , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/patologia , Vírus Sincicial Respiratório Humano/classificação , Vírus Sincicial Respiratório Humano/genética , Vírus Sincicial Respiratório Humano/isolamento & purificação , Índice de Gravidade de Doença , Proteínas Virais de Fusão/imunologia , Carga Viral/genética , Virulência/genética , Replicação Viral/genética
12.
Wellcome Open Res ; 5: 130, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695884

RESUMO

Despite the first case of the novel coronavirus only being reported to the WHO at the end of December 2019, humanities and social science scholars have been quick to subject local, national and international responses to COVID-19 to critique. Through television and radio, blogs, social media and other outlets, historians in particular have situated the ongoing outbreak in relation to previous epidemics and historicised cultural and political responses. This paper furthers these historical considerations of the current pandemic by examining the way the National Health Service (NHS) and discourses of risk have figured in public and policy responses. It suggests that appeals to protect the NHS are based on longer-term anxieties about the service's capacity to care and endure in the face of growing demand, as well as building on the attachment that has developed as a result of this persistence in the face of existential threats. Similarly, the position of elderly, vulnerable and "at risk" patients relates to complex histories in which their place in social and medical hierarchies have been ambiguous. It thus argues that the ways in which time appears as both a threat and a possibility of management in the current crisis form part of a longer trajectory of political and cultural thinking.

13.
Vaccine ; 37(44): 6656-6664, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31542260

RESUMO

Pre-fusion stabilizing mutations (DS-Cav1) in soluble fusion (F) proteins of human respiratory syncytial virus (RSV) were previously reported. Here we investigated the antigenic and immunogenic properties of pre-fusion like RSV F proteins on enveloped virus-like particles (VLP). Additional mutations were introduced to DS-Cav1 (F-dcmTM VLP); fusion peptide deletion and cleavage mutation site 1 (F1d-dcmTM VLP) or both sites (F12d-dcmTM VLP). F1d-dcmTM VLP and F12d-dcmTM VLP displayed higher reactivity against pre-fusion specific site Ø and antigenic site I and II specific monoclonal antibodies, compared to F-dcmTM VLP with DS-Cav1 only. Mice immunized with F1d-dcmTM VLP and F12d-dcmTM VLP induced higher levels of DS-Cav1 pre-fusion specific IgG antibodies, RSV neutralizing activity titers, and effective lung viral clearance after challenge. These results suggest that cleavage site mutations and fusion peptide deletion in addition to DS-Cav1 mutations have contributed to structural stabilization of pre-fusion like F conformation on enveloped VLP, capable of inducing high levels of pre-fusion F specific and RSV neutralizing antibodies.


Assuntos
Imunogenicidade da Vacina , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vírus Sincicial Respiratório Humano/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Proteínas Virais de Fusão/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linhagem Celular , Chlorocebus aethiops , Modelos Animais de Doenças , Feminino , Humanos , Imunização , Camundongos , Mutação , Testes de Neutralização , Vírus Sincicial Respiratório Humano/genética , Células Vero , Proteínas Virais de Fusão/genética
14.
Immune Netw ; 19(3): e18, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31281715

RESUMO

Formalin-inactivated respiratory syncytial virus (RSV) vaccination causes vaccine-enhanced disease (VED) after RSV infection. It is considered that vaccine platforms enabling endogenous synthesis of RSV immunogens would induce favorable immune responses than non-replicating subunit vaccines in avoiding VED. Here, we investigated the immunogenicity, protection, and disease in mice after vaccination with RSV fusion protein (F) encoding plasmid DNA (F-DNA) or virus-like particles presenting RSV F (F-VLP). F-DNA vaccination induced CD8 T cells and RSV neutralizing Abs, whereas F-VLP elicited higher levels of IgG2a isotype and neutralizing Abs, and germinal center B cells, contributing to protection by controlling lung viral loads after RSV challenge. However, mice that were immunized with F-DNA displayed weight loss and pulmonary histopathology, and induced F specific CD8 T cell responses and recruitment of monocytes and plasmacytoid dendritic cells into the lungs. These innate immune parameters, RSV disease, and pulmonary histopathology were lower in mice that were immunized with F-VLP after challenge. This study provides important insight into developing effective and safe RSV vaccines.

15.
J Gen Virol ; 100(7): 1112-1122, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31184573

RESUMO

Respiratory syncytial virus (RSV) remains a leading cause of infant mortality worldwide and exhaustive international efforts are underway to develop a vaccine. However, vaccine development has been hindered by a legacy of vaccine-enhanced disease, poor viral immunogenicity in infants, and genetic and physical instabilities. Natural infection with RSV does not prime for enhanced disease encouraging development of live-attenuated RSV vaccines for infants; however, physical instabilities of RSV may limit vaccine development. The role of RSV strain-specific differences on viral physical stability remains unclear. We have previously demonstrated that the RSV fusion (F) surface glycoprotein is responsible for mediating significant differences in thermostability between strains A2 and A2-line19F. In this study, we performed a more comprehensive analysis to characterize the replication and physical stability of recombinant RSV A and B strains that differed only in viral attachment (G) and/or F surface glycoprotein expression. We observed significant differences in thermal stability, syncytia size, pre-fusion F incorporation and viral growth kinetics in vitro, but limited variations to pH and freeze-thaw inactivation among several tested strains. Consistent with earlier studies, A2-line19F showed significantly enhanced thermal stability over A2, but also restricted growth kinetics in both HEp2 and Vero cells. As expected, no significant differences in susceptibility to UV inactivation were observed. These studies provide the first analysis of the physical stability of multiple strains of RSV, establish a key virus strain associated with enhanced thermal stability compared to conventional lab strain A2, and further support the pivotal role RSV F plays in virus stability.


Assuntos
Infecções por Vírus Respiratório Sincicial/virologia , Vacinas contra Vírus Sincicial Respiratório/química , Vírus Sincicial Respiratório Humano/fisiologia , Proteínas do Envelope Viral/química , Proteínas Virais de Fusão/química , Replicação Viral , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Estabilidade Proteica , Vacinas contra Vírus Sincicial Respiratório/genética , Vacinas contra Vírus Sincicial Respiratório/metabolismo , Vírus Sincicial Respiratório Humano/química , Vírus Sincicial Respiratório Humano/classificação , Vírus Sincicial Respiratório Humano/genética , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/metabolismo
16.
Viruses ; 10(8)2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-30127286

RESUMO

Human respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract disease in young children. With repeat infections throughout life, it can also cause substantial disease in the elderly and in adults with compromised cardiac, pulmonary and immune systems. RSV is a pleomorphic enveloped RNA virus in the Pneumoviridae family. Recently, the three-dimensional (3D) structure of purified RSV particles has been elucidated, revealing three distinct morphological categories: spherical, asymmetric, and filamentous. However, the native 3D structure of RSV particles associated with or released from infected cells has yet to be investigated. In this study, we have established an optimized system for studying RSV structure by imaging RSV-infected cells on transmission electron microscopy (TEM) grids by cryo-electron tomography (cryo-ET). Our results demonstrate that RSV is filamentous across several virus strains and cell lines by cryo-ET, cryo-immuno EM, and thin section TEM techniques. The viral filament length varies from 0.5 to 12 µm and the average filament diameter is approximately 130 nm. Taking advantage of the whole cell tomography technique, we have resolved various stages of RSV assembly. Collectively, our results can facilitate the understanding of viral morphogenesis in RSV and other pleomorphic enveloped viruses.


Assuntos
Vírus Sincicial Respiratório Humano/ultraestrutura , Vírion/ultraestrutura , Montagem de Vírus/fisiologia , Células A549 , Animais , Brônquios/virologia , Linhagem Celular , Chlorocebus aethiops , Microscopia Crioeletrônica/métodos , Tomografia com Microscopia Eletrônica/métodos , Células Epiteliais/ultraestrutura , Células Epiteliais/virologia , Células HeLa , Humanos , Microtomia , Vírus Sincicial Respiratório Humano/fisiologia , Células Vero , Vírion/fisiologia
17.
J Vis Exp ; (136)2018 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-29985365

RESUMO

A microwave deposition technique for silanes, previously described for production of oleophobic fabrics, is adapted to provide a fabric support material that can be subsequently treated by dip coating. Dip coating with a sol preparation provides a supported porous layer on the fabric. In this case, the porous layer is a porphyrin functionalized sorbent system based on a powdered material that has been demonstrated previously for the capture and conversion of phosgene. A representative coating is applied to cotton fabric at a loading level of 10 mg/g. This coating has minimal impact on water vapor transport through the fabric (93% of the support fabric rate) while significantly reducing transport of 2-chloroethyl ethyl sulfide (CEES) through the material (7% of support fabric rate). The described approaches are suitable for use with other fabrics providing amine and hydroxyl groups for modification and can be used in combination with other sol preparations to produce varying functionality.


Assuntos
Compostos de Organossilício/química , Porosidade
18.
Artigo em Inglês | MEDLINE | ID: mdl-29891600

RESUMO

Morbidity and mortality resulting from influenza-like disease are a threat, especially for older adults. To improve case management, next-generation broad-spectrum antiviral therapeutics that are efficacious against major drivers of influenza-like disease, including influenza viruses and respiratory syncytial virus (RSV), are urgently needed. Using a dual-pathogen high-throughput screening protocol for influenza A virus (IAV) and RSV inhibitors, we have identified N4-hydroxycytidine (NHC) as a potent inhibitor of RSV, influenza B viruses, and IAVs of human, avian, and swine origins. Biochemical in vitro polymerase assays and viral RNA sequencing revealed that the ribonucleotide analog is incorporated into nascent viral RNAs in place of cytidine, increasing the frequency of viral mutagenesis. Viral passaging in cell culture in the presence of an inhibitor did not induce robust resistance. Pharmacokinetic profiling demonstrated dose-dependent oral bioavailability of 36 to 56%, sustained levels of the active 5'-triphosphate anabolite in primary human airway cells and mouse lung tissue, and good tolerability after extended dosing at 800 mg/kg of body weight/day. The compound was orally efficacious against RSV and both seasonal and highly pathogenic avian IAVs in mouse models, reducing lung virus loads and alleviating disease biomarkers. Oral dosing reduced IAV burdens in a guinea pig transmission model and suppressed virus spread to uninfected contact animals through direct transmission. Based on its broad-spectrum efficacy and pharmacokinetic properties, NHC is a promising candidate for future clinical development as a treatment option for influenza-like diseases.


Assuntos
Antivirais/farmacologia , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Animais , Células Cultivadas , Cobaias , Humanos , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/genética , Vírus da Influenza B/efeitos dos fármacos , Vírus da Influenza B/genética , Camundongos , RNA Viral/genética , Vírus Sincicial Respiratório Humano/genética , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Vírus Sinciciais Respiratórios/genética
19.
Am J Respir Crit Care Med ; 198(8): 1064-1073, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-29733679

RESUMO

RATIONALE: Recurrent wheeze and asthma are thought to result from alterations in early life immune development following respiratory syncytial virus (RSV) infection. However, prior studies of the nasal immune response to infection have assessed only individual cytokines, which does not capture the whole spectrum of response to infection. OBJECTIVES: To identify nasal immune phenotypes in response to RSV infection and their association with recurrent wheeze. METHODS: A birth cohort of term healthy infants born June to December were recruited and followed to capture the first infant RSV infection. Nasal wash samples were collected during acute respiratory infection, viruses were identified by RT-PCR, and immune-response analytes were assayed using a multianalyte bead-based panel. Immune-response clusters were identified using machine learning, and association with recurrent wheeze at age 1 and 2 years was assessed using logistic regression. MEASUREMENTS AND MAIN RESULTS: We identified two novel and distinct immune-response clusters to RSV and human rhinovirus. In RSV-infected infants, a nasal immune-response cluster characterized by lower non-IFN antiviral immune-response mediators, and higher type-2 and type-17 cytokines was significantly associated with first and second year recurrent wheeze. In comparison, we did not observe this in infants with human rhinovirus acute respiratory infection. Based on network analysis, type-2 and type-17 cytokines were central to the immune response to RSV, whereas growth factors and chemokines were central to the immune response to human rhinovirus. CONCLUSIONS: Distinct immune-response clusters during infant RSV infection and their association with risk of recurrent wheeze provide insights into the risk factors for and mechanisms of asthma development.


Assuntos
Mucosa Nasal/imunologia , Sons Respiratórios/etiologia , Infecções por Vírus Respiratório Sincicial/imunologia , Asma/etiologia , Asma/virologia , Pré-Escolar , Feminino , Humanos , Imunidade , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Mucosa Nasal/virologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Recidiva , Sons Respiratórios/imunologia , Vírus Sincicial Respiratório Humano/imunologia
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