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1.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33688034

RESUMO

The current pandemic of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) highlights an urgent need to develop a safe, efficacious, and durable vaccine. Using a measles virus (rMeV) vaccine strain as the backbone, we developed a series of recombinant attenuated vaccine candidates expressing various forms of the SARS-CoV-2 spike (S) protein and its receptor binding domain (RBD) and evaluated their efficacy in cotton rat, IFNAR-/-mice, IFNAR-/--hCD46 mice, and golden Syrian hamsters. We found that rMeV expressing stabilized prefusion S protein (rMeV-preS) was more potent in inducing SARS-CoV-2-specific neutralizing antibodies than rMeV expressing full-length S protein (rMeV-S), while the rMeVs expressing different lengths of RBD (rMeV-RBD) were the least potent. Animals immunized with rMeV-preS produced higher levels of neutralizing antibody than found in convalescent sera from COVID-19 patients and a strong Th1-biased T cell response. The rMeV-preS also provided complete protection of hamsters from challenge with SARS-CoV-2, preventing replication in lungs and nasal turbinates, body weight loss, cytokine storm, and lung pathology. These data demonstrate that rMeV-preS is a safe and highly efficacious vaccine candidate, supporting its further development as a SARS-CoV-2 vaccine.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Vetores Genéticos , Vírus do Sarampo , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Sintéticas/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/complicações , COVID-19/patologia , Vacinas contra COVID-19/genética , Cricetinae , Modelos Animais de Doenças , Expressão Gênica , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Humanos , Imunização , Imunogenicidade da Vacina , Vírus do Sarampo/genética , Vírus do Sarampo/imunologia , Camundongos , Camundongos Transgênicos , Ratos , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Sintéticas/genética
2.
Elife ; 102021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33463525

RESUMO

Seasonal coronaviruses (OC43, 229E, NL63, and HKU1) are endemic to the human population, regularly infecting and reinfecting humans while typically causing asymptomatic to mild respiratory infections. It is not known to what extent reinfection by these viruses is due to waning immune memory or antigenic drift of the viruses. Here we address the influence of antigenic drift on immune evasion of seasonal coronaviruses. We provide evidence that at least two of these viruses, OC43 and 229E, are undergoing adaptive evolution in regions of the viral spike protein that are exposed to human humoral immunity. This suggests that reinfection may be due, in part, to positively selected genetic changes in these viruses that enable them to escape recognition by the immune system. It is possible that, as with seasonal influenza, these adaptive changes in antigenic regions of the virus would necessitate continual reformulation of a vaccine made against them.


Assuntos
Adaptação Fisiológica/genética , Antígenos Virais/genética , Evolução Biológica , Coronavirus/metabolismo , Estações do Ano , Simulação por Computador , Coronavirus/genética , Regulação Viral da Expressão Gênica , Humanos , Vírus da Influenza A/genética , Vírus do Sarampo/genética , Filogenia
3.
Science ; 368(6497): 1367-1370, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32554594

RESUMO

Many infectious diseases are thought to have emerged in humans after the Neolithic revolution. Although it is broadly accepted that this also applies to measles, the exact date of emergence for this disease is controversial. We sequenced the genome of a 1912 measles virus and used selection-aware molecular clock modeling to determine the divergence date of measles virus and rinderpest virus. This divergence date represents the earliest possible date for the establishment of measles in human populations. Our analyses show that the measles virus potentially arose as early as the sixth century BCE, possibly coinciding with the rise of large cities.


Assuntos
Doenças Transmissíveis Emergentes/história , Evolução Molecular , Variação Genética , Vírus do Sarampo/genética , Sarampo/história , Cidades/história , Doenças Transmissíveis Emergentes/virologia , História Antiga , Humanos , Sarampo/virologia , Vírus da Peste Bovina/genética
4.
J Virol ; 94(17)2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32581091

RESUMO

Measles virus (MeV) is a highly immunotropic and contagious pathogen that can even diminish preexisting antibodies and remains a major cause of childhood morbidity and mortality worldwide despite the availability of effective vaccines. MeV is one of the most extensively studied viruses with respect to the mechanisms of JAK-STAT antagonism. Of the three proteins translated from the MeV P gene, P and V are essential for inactivation of this pathway. However, the lack of data from direct analyses of the underlying interactions means that the detailed molecular mechanism of antagonism remains unresolved. Here, we prepared recombinant MeV V protein, which is responsible for human JAK-STAT antagonism, and a panel of variants, enabling the biophysical characterization of V protein, including direct V/STAT1 and V/STAT2 interaction assays. Unambiguous direct interactions between the host and viral factors, in the absence of other factors such as Jak1 or Tyk2, were observed, and the dissociation constants were quantified for the first time. Our data indicate that interactions between the C-terminal region of V and STAT2 is 1 order of magnitude stronger than that of the N-terminal region of V and STAT1. We also clarified that these interactions are completely independent of each other. Moreover, results of size exclusion chromatography demonstrated that addition of MeV-V displaces STAT2-core, a rigid region of STAT2 lacking the N- and C-terminal domains, from preformed complexes of STAT2-core/IRF-associated domain (IRF9). These results provide a novel model whereby MeV-V can not only inhibit the STAT2/IRF9 interaction but also disrupt preassembled interferon-stimulated gene factor 3.IMPORTANCE To evade host immunity, many pathogenic viruses inactivate host Janus kinase signal transducer and activator of transcription (STAT) signaling pathways using diverse strategies. Measles virus utilizes P and V proteins to counteract this signaling pathway. Data derived largely from cell-based assays have indicated several amino acid residues of P and V proteins as important. However, biophysical properties of V protein or its direct interaction with STAT molecules using purified proteins have not been studied. We have developed novel molecular tools enabling us to identify a novel molecular mechanism for immune evasion whereby V protein disrupts critical immune complexes, providing a clear strategy by which measles virus can suppress interferon-mediated antiviral gene expression.


Assuntos
Fator Gênico 3 Estimulado por Interferon, Subunidade gama/química , Vírus do Sarampo/metabolismo , Fosfoproteínas/química , Fator de Transcrição STAT2/química , Proteínas Virais/química , Sítios de Ligação , Expressão Gênica , Humanos , Evasão da Resposta Imune , Imunidade Inata , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/genética , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Janus Quinases/metabolismo , Vírus do Sarampo/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Ligação Proteica , Domínios Proteicos , Domínios e Motivos de Interação entre Proteínas , Fator de Transcrição STAT1/química , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT2/genética , Fator de Transcrição STAT2/metabolismo , Transdução de Sinais , Proteínas Virais/genética , Proteínas Virais/metabolismo , Dedos de Zinco
5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(6): 946-951, 2020 Jun 10.
Artigo em Chinês | MEDLINE | ID: mdl-32564565

RESUMO

Objective: We isolated and identified the genotypes and molecular characteristics of the imported B3 measles virus (MeV) in Fujian province in 2018. Methods: Throat swab specimens were collected from clinically diagnosed measles patients and tested for viral RNA, using the real-time reverse transcription-polymerase chain reaction after the RNA extraction. Reverse transcription-polymerase chain reaction method was undertaken to amplify the 634 nucleotide acids of 3-terminal of the nucleoprotein gene. A phylogenetic tree was constructed and similarities in homology assessed. Results: We successfully isolated and obtained two measles virus strains and eighteen viral nucleic acid sequences. The Fujian strains were clustered within the same genotype group of WHO genotype B3 reference strains. Compared to the major circulating measles strain genotype B3 in the world, two Fujian strains MV18-41 and MV18-42 showed 100.0% nucleic acid homology to HongKong.CHN/35.18 strain which was isolated from Hong Kong in 2018. The remaining 16 Fujian strains showed the highest homology (99.9%) with the Mvs/Osaka.JPN/38.18/B3 strain isolated from Japan in 2018. Compared with other 23 WHO genotype reference strains, homology on both nucleotide and amino acid of the Fujian strain and the B1 genotype reference strain were the smallest, as 95.1%-95.4% and 95.3%, respectively. The differences of homology between the Fujian strain and H1 genotype reference strain were the largest, as 88.7%-89.0% and 87.3%, respectively. In addition, there were 13 mutation sites between the Fujian strain and the vaccine strain (Shanghai-191) at the 150 amino acid position of carboxy terminus on N protein, However, these sites did not cause functional changes in the protein region. Conclusions: In Fujian province, two strains of B3 genotype measles virus were obtained successfully, which were considered to be new genotype measles virus found in 2018. These findings showed it is necessary to strengthening the monitoring program on imported cases for better control and eliminate the measles virus.


Assuntos
Vírus do Sarampo/genética , Sarampo/virologia , China , Genótipo , Hong Kong , Humanos , Vírus do Sarampo/isolamento & purificação
6.
Arch Virol ; 165(8): 1895-1898, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32462283

RESUMO

We previously reported genotype D11 strains of measles virus that were first isolated from a measles outbreak associated with imported cases in Yunnan province of China by Zhang et al. (Emerg Infect Dis 16(6):943-7, 2010). Genotype D11 has been identified as the 24th genotype of the WHO reference strains. In this study, we sequenced the whole genome of a D11 strain. Phylogenetic analysis using the complete genome sequences of D11 and other reference strains showed that the D11 strain formed a distinct branch that was distant from the other genotypes and was most closely related to the reference strain D7. The M-F non-coding region (NCR) and the N450 coding region sequence (CDS) were found to be the most variable regions. This report provides basic genetic data on genotype D11 for further study of measles evolution and the support for measles elimination.


Assuntos
Genoma Viral/genética , Vírus do Sarampo/genética , China , Surtos de Doenças , Genótipo , Humanos , Sarampo/virologia , Filogenia , Análise de Sequência de DNA/métodos
7.
Sci Adv ; 6(10): eaaz1590, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32181359

RESUMO

Paramyxoviruses are negative-polarity RNA viruses of major clinical importance. The dynamic interaction of the RNA-dependent RNA polymerase (RdRP) complex with the encapsidated RNA genome is mechanistically and structurally poorly understood. Having generated recombinant measles (MeV) and canine distemper (CDV) viruses with truncated nucleocapsid (N) protein showing defects in replication kinetics, we have applied a viral evolution approach to the problem. Passaging of recombinants resulted in long-range compensatory mutations that restored RdRP bioactivity in minigenome assays and efficient replication of engineered viruses. Compensatory mutations clustered at an electronically compatible acidic loop in N-core and a basic face of the phosphoprotein X domain (P-XD). Co-affinity precipitations, biolayer interferometry, and molecular docking revealed an electrostatic-driven transiently forming interface between these domains. The compensatory mutations reduced electrostatic compatibility of these microdomains and lowered coprecipitation efficiency, consistent with a molecular checkpoint function that regulates paramyxovirus polymerase mobility through modulation of conformational stability of the P-XD assembly.


Assuntos
Vírus da Cinomose Canina/genética , Vírus do Sarampo/genética , Proteínas do Nucleocapsídeo/química , Fosfoproteínas/química , Vírus Reordenados/genética , Replicação Viral/genética , Animais , Sítios de Ligação , Linhagem Celular , Chlorocebus aethiops , Clonagem Molecular , Cricetulus , Vírus da Cinomose Canina/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vírus do Sarampo/metabolismo , Simulação de Acoplamento Molecular , Mutação , Proteínas do Nucleocapsídeo/genética , Proteínas do Nucleocapsídeo/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Domínios e Motivos de Interação entre Proteínas , /metabolismo , Vírus Reordenados/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Eletricidade Estática , Células Vero
8.
Aust N Z J Public Health ; 44(2): 160-162, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32190947

RESUMO

OBJECTIVE: Measles continues to be a threat to Australia. While post-eradication risks are low, imported measles cases from overseas travellers who are non-immune can cause small outbreaks. This case report discusses the challenge of identifying wild-type measles in an individual who was recently vaccinated with measles-containing vaccine (MCV). METHODS: A positive polymerase chain reaction (PCR) result for measles for an adult who had recently received a measles-containing vaccine was notified. Investigation revealed no known epidemiological link, recent overseas travel or contact with recent measles cases during the incubation period. RESULTS: The results of the initial sequencing to distinguish between wild-type and vaccine-strain measles were inconclusive. A decision was made to re-run the genotyping, collect additional specimens and quarantine the case until a definitive result was obtained. Sequencing and genotyping revealed that this indeed was a wild-type measles strain. CONCLUSIONS: Changing epidemiology of measles means distinguishing between wild-type and vaccine-strain measles has become a new challenge. Implications for public health: The reflection of the public health management of this case has provided a valuable teaching tool for public health professionals globally, particularly in low incidence measles countries.


Assuntos
Vacina contra Sarampo/efeitos adversos , Vírus do Sarampo/genética , Sarampo/diagnóstico , Adulto , Austrália/epidemiologia , Notificação de Doenças , Surtos de Doenças/prevenção & controle , Feminino , Humanos , Sarampo/prevenção & controle , Vacina contra Sarampo/administração & dosagem , Vírus do Sarampo/classificação , Vírus do Sarampo/isolamento & purificação , Reação em Cadeia da Polimerase , Análise de Sequência , Vacinação
9.
J Gen Virol ; 101(4): 399-409, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32053093

RESUMO

Oncolytic virotherapy is an emerging treatment option for numerous cancers, with several virus families currently being evaluated in clinical trials. More specifically, vaccine-strain measles virus has arisen as a promising candidate for the treatment of different tumour types in several early clinical trials. Replicating viruses, and especially RNA viruses without proofreading polymerases, can rapidly adapt to varying environments by selecting quasispecies with advantageous genetic mutations. Subsequently, these genetic alterations could potentially weaken the safety profile of virotherapy. In this study, we demonstrate that, following an extended period of virus replication in producer or cancer cell lines, the quasispecies consensus sequence of vaccine strain-derived measles virus accrues a remarkably small number of mutations throughout the nonsegmented negative-stranded RNA genome. Interestingly, we detected a nonrandom distribution of genetic alterations within the genome, with an overall decreasing frequency of mutations from the 3' genome start to its 5' end. Comparing the serially passaged viruses to the parental virus on producer cells, we found that the acquired consensus mutations did not drastically change viral replication kinetics or cytolytic potency. Collectively, our data corroborate the genomic stability and excellent safety profile of oncolytic measles virus, thus supporting its continued development and clinical translation as a promising viro-immunotherapeutic.


Assuntos
Instabilidade Genômica , Vírus do Sarampo/genética , Quase-Espécies/genética , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Chlorocebus aethiops , Humanos , Vírus do Sarampo/crescimento & desenvolvimento , Mutação , Terapia Viral Oncolítica , Inoculações Seriadas , Células Vero , Virulência/genética
10.
Euro Surveill ; 25(3)2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31992389

RESUMO

Recognition of measles is crucial to prevent transmissions in the hospital settings. Little is known about the level of recognition of measles and possible causes of not recognising the disease by physicians in the post-vaccine era. We report on a measles outbreak in a paediatric hospital in Austria in January to February 2017 with strikingly high numbers of not recognised cases. The extent and course of the outbreak were assessed via retrospective case finding. Thirteen confirmed measles cases were identified, two with atypical clinical picture. Of eight cases with no known epidemiological link, only one was diagnosed immediately; four were recognised with delay and three only retrospectively. Eleven typical measles cases had four 'unrecognised visits' to the outpatient clinic and 28 on the ward. Two atypical cases had two 'unrecognised visits' to the outpatient clinic and 19 on the ward.Thirteen clinicians did not recognise typical measles (atypical cases not included). Twelve of 23 physicians involved had never encountered a patient with measles before. The direct and indirect costs related to the outbreak were calculated to be over EUR 80,000. Our findings suggest the need to establish regular training programmes about measles, including diagnostic pitfalls in paediatric hospitals.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Vírus do Sarampo/genética , Vírus do Sarampo/imunologia , Sarampo/epidemiologia , Adolescente , Adulto , Áustria/epidemiologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Hospitais Pediátricos , Hospitais Universitários , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Lactente , Masculino , Vírus do Sarampo/isolamento & purificação , RNA Viral/análise , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
12.
Crit Rev Biotechnol ; 40(2): 247-264, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31918573

RESUMO

Oncolytic viruses (including measles virus) offer an alternative approach to reduce the high mortality rate of late-stage cancer. Several measles virus strains infect and lyse cancer cells efficiently, but the broad application of this therapeutic concept is hindered by the large number of infectious particles required (108-1012 TCID50 per dose). The manufacturing process must, therefore, achieve high titers of oncolytic measles virus (OMV) during upstream production and ensure that the virus product is not damaged during purification by applying appropriate downstream processing (DSP) unit operations. DSP is currently a production bottleneck because there are no specific platforms for OMV. Infectious OMV must be recovered as intact, enveloped particles, and host cell proteins and DNA must be reduced to acceptable levels to meet regulatory guidelines that were developed for virus-based vaccines and gene therapy vectors. Handling such high viral titers and process volumes is technologically challenging and expensive. This review considers the state of the art in OMV purification and looks at promising DSP technologies. We discuss here the purification of other enveloped viruses where such technologies could also be applied to OMV. The development of DSP technologies tailored for enveloped viruses is necessary to produce sufficient titers for virotherapy, which could offer hope to millions of patients suffering from incurable cancer.


Assuntos
Antineoplásicos/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Neoplasias/terapia , Terapia Viral Oncolítica , Vírus Oncolíticos/fisiologia , Humanos , Vacina contra Sarampo/uso terapêutico , Vírus do Sarampo/genética , Vírus do Sarampo/imunologia , Vírus do Sarampo/fisiologia , Neoplasias/prevenção & controle , Neoplasias/virologia , Vírus Oncolíticos/genética , Vírus Oncolíticos/imunologia , Vacinas Atenuadas/uso terapêutico
13.
J Virol ; 94(4)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31748390

RESUMO

Measles virus (MeV), like all viruses of the order Mononegavirales, utilizes a complex consisting of genomic RNA, nucleoprotein, the RNA-dependent RNA polymerase, and a polymerase cofactor, the phosphoprotein (P), for transcription and replication. We previously showed that a recombinant MeV that does not express another viral protein, C, has severe transcription and replication deficiencies, including a steeper transcription gradient than the parental virus and generation of defective interfering RNA. This virus is attenuated in vitro and in vivo However, how the C protein operates and whether it is a component of the replication complex remained unclear. Here, we show that C associates with the ribonucleocapsid and forms a complex that can be purified by immunoprecipitation or ultracentrifugation. In the presence of detergent, the C protein is retained on purified ribonucleocapsids less efficiently than the P protein and the polymerase. The C protein is recruited to the ribonucleocapsid through its interaction with the P protein, as shown by immunofluorescence microscopy of cells expressing different combinations of viral proteins and by split luciferase complementation assays. Forty amino-terminal C protein residues are dispensable for the interaction with P, and the carboxyl-terminal half of P is sufficient for the interaction with C. Thus, the C protein, rather than being an "accessory" protein as qualified in textbooks so far, is a ribonucleocapsid-associated protein that interacts with P, thereby increasing replication accuracy and processivity of the polymerase complex.IMPORTANCE Replication of negative-strand RNA viruses relies on two components: a helical ribonucleocapsid and an RNA-dependent RNA polymerase composed of a catalytic subunit, the L protein, and a cofactor, the P protein. We show that the measles virus (MeV) C protein is an additional component of the replication complex. We provide evidence that the C protein is recruited to the ribonucleocapsid by the P protein and map the interacting segments of both C and P proteins. We conclude that the primary function of MeV C is to improve polymerase processivity and accuracy, rather than uniquely to antagonize the type I interferon response. Since most viruses of the Paramyxoviridae family express C proteins, their primary function may be conserved.


Assuntos
Vírus do Sarampo/metabolismo , Nucleoproteínas/genética , Proteínas não Estruturais Virais/metabolismo , Proteínas Virais/genética , Animais , Proteínas de Transporte , Linhagem Celular , Chlorocebus aethiops , Células HEK293 , Células HeLa , Humanos , Sarampo/virologia , Vírus do Sarampo/genética , Proteínas do Nucleocapsídeo , Nucleoproteínas/metabolismo , Fosfoproteínas/metabolismo , Ligação Proteica , Células Vero , Proteínas não Estruturais Virais/fisiologia , Proteínas Virais/metabolismo , Ativação Viral/genética , Replicação Viral/genética
14.
J Virol ; 94(2)2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31619560

RESUMO

Measles virus (MeV) is an enveloped RNA virus bearing two envelope glycoproteins, the hemagglutinin (H) and fusion (F) proteins. Upon receptor binding, the H protein triggers conformational changes of the F protein, causing membrane fusion and subsequent virus entry. MeV may persist in the brain, infecting neurons and causing fatal subacute sclerosing panencephalitis (SSPE). Since neurons do not express either of the MeV receptors, signaling lymphocytic activation molecule (SLAM; also called CD150) and nectin-4, how MeV propagates in neurons is unknown. Recent studies have shown that specific substitutions in the F protein found in MeV isolates from SSPE patients are critical for MeV neuropathogenicity by rendering the protein unstable and hyperfusogenic. Recombinant MeVs possessing the F proteins with such substitutions can spread in primary human neurons and in the brains of mice and hamsters and induce cell-cell fusion in cells lacking SLAM and nectin-4. Here, we show that receptor-blind mutant H proteins that have decreased binding affinities to receptors can support membrane fusion mediated by hyperfusogenic mutant F proteins, but not the wild-type F protein, in cells expressing the corresponding receptors. The results suggest that weak interactions of the H protein with certain molecules (putative neuron receptors) trigger hyperfusogenic F proteins in SSPE patients. Notably, where cell-cell contacts are ensured, the weak cis interaction of the H protein with SLAM on the same cell surface also could trigger hyperfusogenic F proteins. Some enveloped viruses may exploit such cis interactions with receptors to infect target cells, especially in cell-to-cell transmission.IMPORTANCE Measles virus (MeV) may persist in the brain, causing incurable subacute sclerosing panencephalitis (SSPE). Because neurons, the main target in SSPE, do not express receptors for wild-type (WT) MeV, how MeV propagates in the brain is a key question for the disease. Recent studies have demonstrated that specific substitutions in the MeV fusion (F) protein are critical for neuropathogenicity. Here, we show that weak cis and trans interactions of the MeV attachment protein with receptors that are not sufficient to trigger the WT MeV F protein can trigger the mutant F proteins from neuropathogenic MeV isolates. Our study not only provides an important clue to understand MeV neuropathogenicity but also reveals a novel viral strategy to expand cell tropism.


Assuntos
Moléculas de Adesão Celular/metabolismo , Hemaglutininas Virais/metabolismo , Vírus do Sarampo/metabolismo , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo , Panencefalite Esclerosante Subaguda/metabolismo , Proteínas Virais de Fusão/metabolismo , Animais , Moléculas de Adesão Celular/genética , Linhagem Celular , Cricetinae , Hemaglutininas Virais/genética , Humanos , Vírus do Sarampo/genética , Vírus do Sarampo/patogenicidade , Camundongos , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária/genética , Panencefalite Esclerosante Subaguda/genética , Panencefalite Esclerosante Subaguda/patologia , Proteínas Virais de Fusão/genética
15.
J Infect Public Health ; 13(4): 619-624, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31561963

RESUMO

BACKGROUND: From January 2017 to June 2018 more than 7000 measles cases were reported in Italy, of which more than 400 among unvaccinated healthcare workers. We described a measles outbreak occurred in Western Liguria, Italy, characterized by a high involvement of healthcare workers and hospital visitors. METHODS: Suspected measles cases and data regarding vaccination status and clinical management of the patients were collected by reviewing 3 different surveillance systems: the routine mandatory notification system, the National Integrated Surveillance System for Measles and Rubella and the regional reference laboratory for measles diagnosis. RESULTS: Thirty-six cases were reported, with a median age of 31 years and >95% in unvaccinated subjects. One death occurred, 15 cases were hospitalized. Hospital transmission was confirmed or suspected in 12 cases; amongst this cases, 5 were healthcare workers (a gynaecologist, an obstetric nurse, a radiologist, a physiotherapist and a nurse working in an infectious disease ward), all certified unvaccinated. Phylogenetic analysis revealed the circulation of a single B3 genotype variant. CONCLUSIONS: Our experience highlighted the key role of nosocomial transmission and the need for targeted strategies, in particular (i) to implement a measles catch-up immunization campaign in susceptible groups, especially in healthcare workers, (ii) to intensify the check of immunisation status of healthcare workers and to offer vaccination for those who need it, (iii) to improve timeliness and completeness of surveillance systems. Efforts are needed to guarantee the safety of the hospital and the reliability of the healthcare workers. Only high vaccination coverage among HCWs can prevent the diffusion of measles in the hospital setting.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Transmissão de Doença Infecciosa do Paciente para o Profissional/estatística & dados numéricos , Sarampo/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/transmissão , Infecção Hospitalar/virologia , Feminino , Humanos , Lactente , Itália/epidemiologia , Masculino , Sarampo/prevenção & controle , Vacina contra Sarampo/uso terapêutico , Vírus do Sarampo/genética , Recursos Humanos em Hospital/estatística & dados numéricos , Filogenia , Adulto Jovem
16.
Arch Dis Child ; 105(9): 896-899, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-30636224

RESUMO

OBJECTIVE AND DESIGN: Risk factors for severe measles are poorly investigated in high-income countries. The Italian Society for Paediatric Infectious Diseases conducted a retrospective study in children hospitalised for measles from January 2016 to August 2017 to investigate the risk factors for severe outcome defined by the presence of long-lasting sequelae, need of intensive care or death. RESULTS: Nineteen hospitals enrolled 249 children (median age 14.5 months): 207 (83%) children developed a complication and 3 (1%) died. Neutropaenia was more commonly reported in children with B3-genotype compared with other genotypes (29.5% vs 7.7%, p=0.01). Pancreatitis (adjusted OR [aOR] 9.19, p=0.01) and encephalitis (aOR 7.02, p=0.04) were related to severe outcome in multivariable analysis, as well as C reactive protein (CRP) (aOR 1.1, p=0.028), the increase of which predicted severe outcome (area under the receiver operating characteristic curve 0.67, 95% CI 0.52 to 0.82). CRP values >2 mg/dL were related to higher risk of complications (OR 2.0, 95% CI 1.15 to 3.7, p=0.01) or severe outcome (OR 4.13, 95% CI 1.43 to 11.8, p<0.01). CONCLUSION: The risk of severe outcome in measles is independent of age and underlying conditions, but is related to the development of organ complications and may be predicted by CRP value.


Assuntos
Sarampo/complicações , Criança , Pré-Escolar , Encefalite Viral/etiologia , Feminino , Humanos , Lactente , Unidades de Terapia Intensiva Pediátrica/estatística & dados numéricos , Itália/epidemiologia , Masculino , Sarampo/mortalidade , Sarampo/patologia , Vírus do Sarampo/genética , Neutropenia/etiologia , Pancreatite/etiologia , Curva ROC , Fatores de Risco , Índice de Gravidade de Doença
17.
J Infect Public Health ; 13(2): 309-312, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31431423

RESUMO

Measles infection is endemic in Nigeria, with outbreaks occurring yearly. Genotype B3 is the dominant genotype and the only genotype characterized from Nigeria. The current study investigated the phylogenetic and Bayesian evolutionary dynamics of Nigerian measles virus Nucleoprotein (N) sequences isolated from Lagos and Ibadan, Nigeria. A total of 120 throat swab samples were analysed by RT-PCR and Sanger sequencing. Phylogenetic analysis and Bayesian demographic reconstructions were done using MEGA and BEAST software. Measles RNA positivity was 14.2% (17/120), age range 0-1 recorded the highest rate with 40.83%. Study sequences clustered within clade B3.1. The evolutionary rate of analysed B3 sequences was 1.108×10-3, higher posterior density HPD interval (1.462×10-3 - 7.886×10-4)subs/site/year. The time to most recent common ancestor (TMRC), was 1991. The Bayesian skyride analysis(BSP) of West African MV cladeB3.1, showed a stable, steady state population demography. This study has reemphasised the dominance of clade B3.1 in Nigeria. We have shown that clade B3.1 was recently introduced into circulation and has a slow population expansion. We advocate for the institution of molecular surveillance country wide in order to help monitor strain diversity and genetic evolution of Measles in Nigeria.


Assuntos
Vírus do Sarampo/genética , Sarampo/virologia , Teorema de Bayes , Pré-Escolar , Evolução Molecular , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Sarampo/epidemiologia , Vírus do Sarampo/classificação , Vírus do Sarampo/isolamento & purificação , Nigéria , Proteínas do Nucleocapsídeo , Nucleoproteínas/genética , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Proteínas Virais/genética
18.
Med Sci Monit ; 25: 9245-9254, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31800568

RESUMO

BACKGROUND Measles morbidity and mortality were significantly reduced after the measles vaccine was introduced in China in 1965. However, measles outbreaks easily occur in densely populated areas, especially where there is no universal vaccination. The outbreak that occurred in Shenzhen, the Chinese city with the largest internal immigration, provides a lesson in measles virus mutation and measles prevention. The present study is a phylogenetic analysis of measles viruses and comparison of clinical signs between individuals with and without vaccination. MATERIAL AND METHODS We performed phylogenetic analysis of the nucleoprotein (N) genes of measles virus from 129 measles patients in Shenzhen from January 2015 to July 2019. Phylogenetic trees were constructed using the neighbor-joining method. RESULTS The phylogenetic analysis showed all viruses were classified into genotype H1. In addition, there is often a seasonal measles outbreak in July each year. The clinical data showed that patients who were unvaccinated were more likely to have coughing, chronic bronchitis, conjunctivitis, catarrh, Koplik spots, and diarrhea. Children of migrant workers and those living in mountainous and rural districts accounted for most measles cases. CONCLUSIONS Our results showed there was a seasonal measles outbreak in Shenzhen Children's Hospital. All the measles virus from 129 measles patients were H1 viruses. The clinical signs also showed a difference between unvaccinated and vaccinated patients. Moreover, most of the unvaccinated patients came from migrant worker families. We suggest there is a need for increased health promotion and vaccination programs for migrant workers and people living in remote villages.


Assuntos
Vírus do Sarampo/genética , Sarampo/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Surtos de Doenças , Feminino , Genótipo , Humanos , Imunoglobulina M , Lactente , Recém-Nascido , Masculino , Vacina contra Sarampo , Vírus do Sarampo/patogenicidade , Proteínas do Nucleocapsídeo , Nucleoproteínas/genética , Filogenia , Vacinação , Proteínas Virais/genética
19.
mBio ; 10(6)2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31772054

RESUMO

Measles virus (MeV) is a highly contagious human pathogen that continues to be a worldwide health burden. One of the challenges for the study of MeV spread is the identification of model systems that accurately reflect how MeV behaves in humans. For our studies, we use unpassaged, well-differentiated primary cultures of airway epithelial cells from human donor lungs to examine MeV infection and spread. Here, we show that the main components of the MeV ribonucleoprotein complex (RNP), the nucleocapsid and phosphoprotein, colocalize with the apical and circumapical F-actin networks. To better understand how MeV infections spread across the airway epithelium, we generated a recombinant virus incorporating chimeric fluorescent proteins in its RNP complex. By live cell imaging, we observed rapid movement of RNPs along the circumapical F-actin rings of newly infected cells. This strikingly rapid mechanism of horizontal trafficking across epithelia is consistent with the opening of pores between columnar cells by the viral membrane fusion apparatus. Our work provides mechanistic insights into how MeV rapidly spreads through airway epithelial cells, contributing to its extremely contagious nature.IMPORTANCE The ability of viral particles to directly spread cell to cell within the airways without particle release is considered to be highly advantageous to many respiratory viruses. Our previous studies in well-differentiated, primary human airway epithelial cells suggest that measles virus (MeV) spreads cell to cell by eliciting the formation of intercellular membrane pores. Based on a newly generated ribonucleoprotein complex (RNP) "tracker" virus, we document by live-cell microscopy that MeV RNPs move along F-actin rings before entering a new cell. Thus, rather than diffusing through the cytoplasm of a newly infected columnar cell, RNPs take advantage of the cytoskeletal infrastructure to rapidly spread laterally across the human airway epithelium. This results in rapid horizontal spread through the epithelium that does not require particle release.


Assuntos
Actinas/metabolismo , Células Epiteliais/virologia , Vírus do Sarampo/metabolismo , Sarampo/virologia , Ribonucleoproteínas/metabolismo , Proteínas Virais/metabolismo , Diferenciação Celular , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Humanos , Pulmão/citologia , Pulmão/metabolismo , Pulmão/virologia , Sarampo/metabolismo , Vírus do Sarampo/genética , Ribonucleoproteínas/genética , Proteínas Virais/genética
20.
Hum Gene Ther ; 30(12): 1477-1493, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31578886

RESUMO

Cell and gene therapies are finally becoming viable patient treatment options, with both T cell- and hematopoietic stem cell (HSC)-based therapies being approved to market in Europe. However, these therapies, which involve the use of viral vector to modify the target cells, are expensive and there is an urgent need to reduce manufacturing costs. One major cost factor is the viral vector production itself, therefore improving the gene modification efficiency could significantly reduce the amount of vector required per patient. This study describes the use of a transduction enhancing peptide, Vectofusin-1®, to improve the transduction efficiency of primary target cells using lentiviral and gammaretroviral vectors (LV and RV) pseudotyped with a variety of envelope proteins. Using Vectofusin-1 in combination with LV pseudotyped with viral glycoproteins derived from baboon endogenous retrovirus, feline endogenous virus (RD114), and measles virus (MV), a strongly improved transduction of HSCs, B cells and T cells, even when cultivated under low stimulation conditions, could be observed. The formation of Vectofusin-1 complexes with MV-LV retargeted to CD20 did not alter the selectivity in mixed cell culture populations, emphasizing the precision of this targeting technology. Functional, ErbB2-specific chimeric antigen receptor-expressing T cells could be generated using a gibbon ape leukemia virus (GALV)-pseudotyped RV. Using a variety of viral vectors and target cells, Vectofusin-1 performed in a comparable manner to the traditionally used surface-bound recombinant fibronectin. As Vectofusin-1 is a soluble peptide, it was possible to easily transfer the T cell transduction method to an automated closed manufacturing platform, where proof of concept studies demonstrated efficient genetic modification of T cells with GALV-RV and RD114-RV and the subsequent expansion of mainly central memory T cells to a clinically relevant dose.


Assuntos
Terapia Genética , Vetores Genéticos/genética , Células-Tronco Hematopoéticas/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Antígenos CD20/genética , Linfócitos B/virologia , Gammaretrovirus/genética , Vetores Genéticos/biossíntese , Vetores Genéticos/uso terapêutico , Glicoproteínas/genética , Células-Tronco Hematopoéticas/virologia , Humanos , Lentivirus/genética , Vírus da Leucemia do Macaco Gibão/genética , Vírus do Sarampo/genética , Peptídeos/genética , Retroviridae/genética , Linfócitos T/virologia , Transdução Genética , Proteínas do Envelope Viral/genética
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