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1.
Bioscience ; 73(11): 814-829, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38125826

RESUMO

Each year, SARS-CoV-2 is infecting an increasingly unprecedented number of species. In the present article, we combine mammalian phylogeny with the genetic characteristics of isolates found in mammals to elaborate on the host-range potential of SARS-CoV-2. Infections in nonhuman mammals mirror those of contemporary viral strains circulating in humans, although, in certain species, extensive viral circulation has led to unique genetic signatures. As in other recent studies, we found that the conservation of the ACE2 receptor cannot be considered the sole major determinant of susceptibility. However, we are able to identify major clades and families as candidates for increased surveillance. On the basis of our findings, we argue that the use of the term panzootic could be a more appropriate term than pandemic to describe the ongoing scenario. This term better captures the magnitude of the SARS-CoV-2 host range and would hopefully inspire inclusive policy actions, including systematic screenings, that could better support the management of this worldwide event.

2.
Global Health ; 19(1): 44, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386579

RESUMO

BACKGROUND: Research on health and sustainable development is growing at a pace such that conventional literature review methods appear increasingly unable to synthesize all relevant evidence. This paper employs a novel combination of natural language processing (NLP) and network science techniques to address this problem and to answer two questions: (1) how is health thematically interconnected with the Sustainable Development Goals (SDGs) in global science? (2) What specific themes have emerged in research at the intersection between SDG 3 ("Good health and well-being") and other sustainability goals? METHODS: After a descriptive analysis of the integration between SDGs in twenty years of global science (2001-2020) as indexed by dimensions.ai, we analyze abstracts of articles that are simultaneously relevant to SDG 3 and at least one other SDG (N = 27,928). We use the top2vec algorithm to discover topics in this corpus and measure semantic closeness between these topics. We then use network science methods to describe the network of substantive relationships between the topics and identify 'zipper themes', actionable domains of research and policy to co-advance health and other sustainability goals simultaneously. RESULTS: We observe a clear increase in scientific research integrating SDG 3 and other SDGs since 2001, both in absolute and relative terms, especially on topics relevant to interconnections between health and SDGs 2 ("Zero hunger"), 4 ("Quality education"), and 11 ("Sustainable cities and communities"). We distill a network of 197 topics from literature on health and sustainable development, with 19 distinct network communities - areas of growing integration with potential to further bridge health and sustainability science and policy. Literature focused explicitly on the SDGs is highly central in this network, while topical overlaps between SDG 3 and the environmental SDGs (12-15) are under-developed. CONCLUSION: Our analysis demonstrates the feasibility and promise of NLP and network science for synthesizing large amounts of health-related scientific literature and for suggesting novel research and policy domains to co-advance multiple SDGs. Many of the 'zipper themes' identified by our method resonate with the One Health perspective that human, animal, and plant health are closely interdependent. This and similar perspectives will help meet the challenge of 'rewiring' sustainability research to co-advance goals in health and sustainability.


Assuntos
Processamento de Linguagem Natural , Saúde Única , Animais , Humanos , Desenvolvimento Sustentável , Cidades , Escolaridade
3.
Euro Surveill ; 28(16)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37078883

RESUMO

BackgroundThe Epidemic Intelligence from Open Sources (EIOS) system, jointly developed by the World Health Organisation (WHO), the Joint Research Centre (JRC) of the European Commission and various partners, is a web-based platform that facilitate the monitoring of information on public health threats in near real-time from thousands of online sources.AimsTo assess the capacity of the EIOS system to strengthen data collection for neglected diseases of public health importance, and to evaluate the use of EIOS data for improving the understanding of the geographic extents of diseases and their level of risk.MethodsA Bayesian additive regression trees (BART) model was implemented to map the risk of Crimean-Congo haemorrhagic fever (CCHF) occurrence in 52 countries and territories within the European Region between January 2012 and March 2022 using data on CCHF occurrence retrieved from the EIOS system.ResultsThe model found a positive association between all temperature-related variables and the probability of CCHF occurrence, with an increased risk in warmer and drier areas. The highest risk of CCHF was found in the Mediterranean basin and in areas bordering the Black Sea. There was a general decreasing risk trend from south to north across the entire European Region.ConclusionThe study highlights that the information gathered by public health intelligence can be used to build a disease risk map. Internet-based sources could aid in the assessment of new or changing risks and planning effective actions in target areas.


Assuntos
Epidemias , Vírus da Febre Hemorrágica da Crimeia-Congo , Febre Hemorrágica da Crimeia , Humanos , Febre Hemorrágica da Crimeia/diagnóstico , Febre Hemorrágica da Crimeia/epidemiologia , Doenças Negligenciadas/epidemiologia , Teorema de Bayes
5.
Nature ; 566(7744): 326, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30783287
6.
J Virol ; 92(20)2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30089689

RESUMO

The rise of populist movements worldwide is challenging science and motivating scientists to join the debate and enter politics. Based on my experience, taking a public stand will not come without slanderous personal and institutional attacks as an attempt to shake scientific credibility. The virology community is at risk of similar misrepresentation; reflection on this topic, particularly on how to address such challenges, should be a priority, given we are in the "post-truth" era.


Assuntos
Pesquisa Biomédica/tendências , Política , Confiança , Virologia/tendências
9.
Avian Pathol ; 46(2): 224-233, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27807985

RESUMO

The evolution of highly pathogenic H5N1 avian influenza viruses (HPAI-H5N1) has resulted in the appearance of a number of diverse groups of HPAI-H5N1 based on the presence of genetically similar clusters of their haemagglutinin sequences (clades). An H5 antigen encoded by a recombinant baculovirus and expressed in insect cells was used for oil-emulsion-based vaccine prototypes. In several experiments, vaccination was performed at 10 days of age, followed by challenge infection on day 21 post vaccination (PV) with HPAI-H5N1 clades 2.2, 2.2.1, and 2.3.2. A further challenge infection with HPAI-H5N1 clade 2.2.1 was performed at day 42 PV. High haemagglutination inhibition titres were observed for the recH5 vaccine antigen, and lower haemagglutination inhibition titres for the challenge virus antigens. Nevertheless, the rate of protection from mortality and clinical signs was 100% when challenged at 21 days PV and 42 days PV, indicating protection over the entire broiler chicken rearing period without a second vaccination. The unvaccinated control chickens mostly died between two and five days after challenge infection. A low level of viral RNA was detected by reverse transcription followed by a quantitative polymerase chain reaction in a limited number of birds for a short period after challenge infection, indicating a limited spread of HPAI-H5N1 at flock level. Furthermore, it was observed that the vaccine can be used in a differentiation infected from vaccinated animals (DIVA) approach, based on the detection of nucleoprotein antibodies in vaccinated/challenged chickens. The vaccine fulfilled all expectations of an inactivated vaccine after one vaccination against challenge with different clades of H5N1-HPAI and is suitable for a DIVA approach.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Aviária/prevenção & controle , Proteínas/imunologia , Animais , Baculoviridae/genética , Baculoviridae/metabolismo , Embrião de Galinha , Galinhas , Feminino , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/patogenicidade , Influenza Aviária/virologia , Insetos , Peptídeos , Proteínas/genética , Organismos Livres de Patógenos Específicos , Vacinação/veterinária , Vacinas de Produtos Inativados
11.
J Gen Virol ; 97(9): 2166-2179, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27417501

RESUMO

Pancreatic ductal adenocarcinoma (PDA) is one of the leading causes of cancer-related deaths worldwide and the development of new treatment strategies for PDA patients is of crucial importance. Virotherapy uses natural or engineered oncolytic viruses (OVs) to selectively kill tumour cells. Due to their genetic heterogeneity, PDA cells are highly variable in their permissiveness to various OVs. The avian influenza A virus (IAV) H7N3 A/turkey/Italy/2962/03 is a potent inducer of apoptosis in PDA cells previously shown to be resistant to other OVs (Kasloff et al., 2014), suggesting that it might be effective against specific subclasses of pancreatic cancer. To improve the selectivity of the avian influenza isolate for PDA cells, here confirmed deficient for IFN response, we engineered a truncation in the NS1 gene that is the major virus-encoded IFN antagonist. The recombinant virus (NS1-77) replicated efficiently in PDA cells, but was attenuated in non-malignant pancreatic ductal cells, in which it induced a potent IFN response that acted upon bystander uninfected cancer cells, triggering their death. The engineered virus displayed an enhanced ability to debulk a PDA-derived tumour in xenograft mouse model. Our results highlight the possibility of selecting an IAV strain from the diverse natural avian reservoir on the basis of its inherent oncolytic potency in specific PDA subclasses and, through engineering, improve its safety, selectivity and debulking activity for cancer treatment.


Assuntos
Adenocarcinoma/terapia , Carcinoma Ductal Pancreático/terapia , Vírus da Influenza A Subtipo H7N3/isolamento & purificação , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/isolamento & purificação , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Xenoenxertos , Humanos , Fatores Imunológicos/genética , Fatores Imunológicos/metabolismo , Vírus da Influenza A Subtipo H7N3/genética , Vírus da Influenza A Subtipo H7N3/fisiologia , Camundongos , Camundongos SCID , Vírus Oncolíticos/genética , Deleção de Sequência , Resultado do Tratamento , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Replicação Viral
12.
Emerg Infect Dis ; 21(4): 673-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25811830

RESUMO

Phylogenetic analysis of influenza viruses collected during December 2009-February 2010 from chickens in live poultry retail shops in Lahore, Pakistan, showed influenza A(H9N2) lineage polymerase and nonstructural genes generate through inter- and intrasubtypic reassortments. Many amino acid signatures observed were characteristic of human isolates; hence, their circulation could enhance inter- or intrasubtypic reassortment.


Assuntos
Galinhas , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Vírus Reordenados , Substituição de Aminoácidos , Animais , Genes Virais , Geografia , História do Século XXI , Influenza Aviária/história , Dados de Sequência Molecular , Mutação , Paquistão/epidemiologia
13.
J Gen Virol ; 96(Pt 5): 969-974, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25593159

RESUMO

Influenza A viruses circulate in a wide range of animals. H3N8 equine influenza virus (EIV) is an avian-origin virus that has established in dogs as canine influenza virus (CIV) and has also been isolated from camels and pigs. Previous work suggests that mutations acquired during EIV evolution might have played a role in CIV emergence. Given the potential role of pigs as a source of human infections, we determined the ability of H3N8 EIVs to replicate in pig cell lines and in respiratory explants. We show that phylogenetically distinct EIVs display different infection phenotypes along the pig respiratory tract, but not in cell lines. Our results suggest that EIV displays a dynamic host range along its evolutionary history, supporting the view that evolutionary processes play important roles in host range and tropism and also underscoring the utility of using explant cultures to study influenza pathogenesis.


Assuntos
Vírus da Influenza A Subtipo H3N8/fisiologia , Sistema Respiratório/virologia , Tropismo Viral , Animais , Linhagem Celular , Especificidade de Hospedeiro , Vírus da Influenza A Subtipo H3N8/isolamento & purificação , Suínos , Replicação Viral
14.
J Virol ; 88(16): 9321-34, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24899201

RESUMO

UNLABELLED: Pancreatic ductal adenocarcinoma (PDA) is the most lethal form of human cancer, with dismal survival rates due to late-stage diagnoses and a lack of efficacious therapies. Building on the observation that avian influenza A viruses (IAVs) have a tropism for the pancreas in vivo, the present study was aimed at testing the efficacy of IAVs as oncolytic agents for killing human PDA cell lines. Receptor characterization confirmed that human PDA cell lines express the alpha-2,3- and the alpha-2,6-linked glycan receptor for avian and human IAVs, respectively. PDA cell lines were sensitive to infection by human and avian IAV isolates, which is consistent with this finding. Growth kinetic experiments showed preferential virus replication in PDA cells over that in a nontransformed pancreatic ductal cell line. Finally, at early time points posttreatment, infection with IAVs caused higher levels of apoptosis in PDA cells than gemcitabine and cisplatin, which are the cornerstone of current therapies for PDA. In the BxPC-3 PDA cell line, apoptosis resulted from the engagement of the intrinsic mitochondrial pathway. Importantly, IAVs did not induce apoptosis in nontransformed pancreatic ductal HPDE6 cells. Using a model based on the growth of a PDA cell line as a xenograft in SCID mice, we also show that a slightly pathogenic avian IAV significantly inhibited tumor growth following intratumoral injection. Taken together, these results are the first to suggest that IAVs may hold promise as future agents of oncolytic virotherapy against pancreatic ductal adenocarcinomas. IMPORTANCE: Despite intensive studies aimed at designing new therapeutic approaches, PDA still retains the most dismal prognosis among human cancers. In the present study, we provide the first evidence indicating that avian IAVs of low pathogenicity display a tropism for human PDA cells, resulting in viral RNA replication and a potent induction of apoptosis in vitro and antitumor effects in vivo. These results suggest that slightly pathogenic IAVs may prove to be effective for oncolytic virotherapy of PDA and provide grounds for further studies to develop specific and targeted viruses, with the aim of testing their efficacy in clinical contexts.


Assuntos
Carcinoma Ductal Pancreático/terapia , Carcinoma Ductal Pancreático/virologia , Vírus da Influenza A/metabolismo , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/metabolismo , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/virologia , Animais , Apoptose/genética , Aves , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Influenza Aviária , Injeções Intralesionais/métodos , Camundongos , Camundongos SCID , Neoplasias Pancreáticas/metabolismo , Replicação Viral/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias Pancreáticas
15.
J Virol ; 88(12): 6623-35, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24696487

RESUMO

UNLABELLED: Avian H7 influenza viruses are recognized as potential pandemic viruses, as personnel often become infected during poultry outbreaks. H7 infections in humans typically cause mild conjunctivitis; however, the H7N9 outbreak in the spring of 2013 has resulted in severe respiratory disease. To date, no H7 viruses have acquired the ability for sustained transmission among humans. Airborne transmission is considered a requirement for the emergence of pandemic influenza, and advanced knowledge of the molecular changes or signature required for transmission would allow early identification of pandemic vaccine seed stocks, screening and stockpiling of antiviral compounds, and eradication efforts focused on flocks harboring threatening viruses. Thus, we sought to determine if a highly pathogenic influenza A H7N1 (A/H7N1) virus with no history of human infection could become capable of airborne transmission among ferrets. We show that after 10 serial passages, A/H7N1 developed the ability to be transmitted to cohoused and airborne contact ferrets. Four amino acid mutations (PB2 T81I, NP V284M, and M1 R95K and Q211K) in the internal genes and a minimal amino acid mutation (K/R313R) in the stalk region of the hemagglutinin protein were associated with airborne transmission. Furthermore, transmission was not associated with loss of virulence. These findings highlight the importance of the internal genes in host adaptation and suggest that natural isolates carrying these mutations be further evaluated. Our results demonstrate that a highly pathogenic avian H7 virus can become capable of airborne transmission in a mammalian host, and they support ongoing surveillance and pandemic H7 vaccine development. IMPORTANCE: The major findings of this report are that a highly pathogenic strain of H7N1 avian influenza virus can be adapted to become capable of airborne transmission in mammals without mutations altering receptor specificity. Changes in receptor specificity have been shown to play a role in the ability of avian influenza viruses to cross the species barrier, and these changes are assumed to be essential. The work reported here challenges this paradigm, at least for the influenza viruses of the H7 subtype, which have recently become the focus of major attention, as they have crossed to humans.


Assuntos
Microbiologia do Ar , Vírus da Influenza A Subtipo H7N1/fisiologia , Influenza Humana/transmissão , Influenza Humana/virologia , Adaptação Fisiológica , Animais , Modelos Animais de Doenças , Feminino , Furões , Humanos , Vírus da Influenza A Subtipo H7N1/genética , Vírus da Influenza A Subtipo H7N1/patogenicidade , Inoculações Seriadas , Virulência
16.
Avian Pathol ; 44(6): 498-508, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26365055

RESUMO

In order to investigate the pancreatic lesions caused by the infection with either H7N1 or H7N3 low-pathogenicity avian influenza viruses, 28 experimentally infected turkeys were submitted for histopathology, immunohistochemistry, haematobiochemistry and real-time reverse transcriptase polymerase chain reaction after different days post-infection (DPI). The localization of viral antigen and the measurement of insulin and glucagon expression in the pancreas were assessed to verify the progression from pancreatitis to metabolic disorders, such as diabetes. At the early infection phase (4-7 DPI), a severe acute necrotizing pancreatitis was recognized. During the intermediate phase (8-17 DPI), a mixed acute/chronic change associated with regenerative ductular proliferation was observed. A loss of pancreatic islets was detected in most severe cases and viral antigen was found in the pancreas of 11/28 turkeys (4-10 DPI) with the most severe histological damage. In turkeys euthanized at 39 DPI (late phase), a chronic fibrosing pancreatitis was observed with the reestablishment of both the exocrine and the endocrine pancreas. Insulin and glucagon expression manifested a progressive decrease with subsequent ductular positivity. Haematobiochemistry revealed increased lipasemia in the first week post-infection and hyperglycaemia in the second, with a progressive normalization within 21 DPI. This study allowed the identification of progressive virus-associated exocrine and endocrine pancreatic damage, suggesting that influenza virus might be responsible for metabolic derangements. Moreover, it highlighted a remarkable post-damage hyperplastic and reparative process from a presumptive common exocrine/endocrine precursor. This potential regeneration deserves further investigation for its relevance in a therapeutic perspective to replace lost and non-functional cells in diabetes mellitus.


Assuntos
Antígenos Virais/imunologia , Vírus da Influenza A Subtipo H7N1/imunologia , Vírus da Influenza A Subtipo H7N3/imunologia , Influenza Aviária/patologia , Doenças das Aves Domésticas/patologia , Regeneração , Animais , Feminino , Hiperglicemia , Influenza Aviária/virologia , Ilhotas Pancreáticas/patologia , Ilhotas Pancreáticas/fisiologia , Pâncreas/patologia , Pâncreas/fisiologia , Pâncreas Exócrino/patologia , Pâncreas Exócrino/fisiologia , Doenças das Aves Domésticas/virologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Perus
17.
J Virol ; 87(1): 597-610, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23097451

RESUMO

Influenza A viruses commonly cause pancreatitis in naturally and experimentally infected animals. In this study, we report the results of in vivo investigations carried out to establish whether influenza virus infection could cause metabolic disorders linked to pancreatic infection. In addition, in vitro tests in human pancreatic islets and in human pancreatic cell lines were performed to evaluate viral growth and cell damage. Infection of an avian model with two low-pathogenicity avian influenza isolates caused pancreatic damage resulting in hyperlipasemia in over 50% of subjects, which evolved into hyperglycemia and subsequently diabetes. Histopathology of the pancreas showed signs of an acute infection resulting in severe fibrosis and disruption of the structure of the organ. Influenza virus nucleoprotein was detected by immunohistochemistry (IHC) in the acinar tissue. Human seasonal H1N1 and H3N2 viruses and avian H7N1 and H7N3 influenza virus isolates were able to infect a selection of human pancreatic cell lines. Human viruses were also shown to be able to infect human pancreatic islets. In situ hybridization assays indicated that viral nucleoprotein could be detected in beta cells. The cytokine activation profile indicated a significant increase of MIG/CXCL9, IP-10/CXCL10, RANTES/CCL5, MIP1b/CCL4, Groa/CXCL1, interleukin 8 (IL-8)/CXCL8, tumor necrosis factor alpha (TNF-α), and IL-6. Our findings indicate that influenza virus infection may play a role as a causative agent of pancreatitis and diabetes in humans and other mammals.


Assuntos
Diabetes Mellitus/virologia , Vírus da Influenza A/patogenicidade , Pancreatite/complicações , Pancreatite/virologia , Animais , Antígenos Virais/análise , Linhagem Celular , Diabetes Mellitus/etiologia , Modelos Animais de Doenças , Feminino , Histocitoquímica , Humanos , Imuno-Histoquímica , Células Secretoras de Insulina/virologia , Dados de Sequência Molecular , Nucleoproteínas/análise , Pâncreas/patologia , Pâncreas/virologia , Análise de Sequência de DNA , Perus
18.
Virus Genes ; 48(2): 366-71, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24242847

RESUMO

AlphaCoV and lineage C betaCoV, genetically similar to those identified in Spanish related bat species, have been detected in Italian Myotis blithii and Eptesicus serotinus, respectively, out of 75 anal swabs collected from Vespertilionidae between 2009 and 2012. Sequence analysis of the 816-bp obtained RdRp sequence fragment indicates a 96.9 % amino acid identity of the Italian lineage C betaCoV with the recent Middle East Respiratory Syndrome Coronavirus (MERS-CoV, Genbank accession number KF192507). This is the first documented occurrence of a lineage C betaCoV in the Italian bat population, notably in E. serotinus.


Assuntos
Quirópteros/virologia , Infecções por Coronavirus/virologia , Coronavirus/classificação , Sequência de Aminoácidos , Animais , Itália , Dados de Sequência Molecular , Filogenia , Homologia de Sequência de Aminoácidos
19.
Trop Anim Health Prod ; 46(2): 299-304, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24146293

RESUMO

Newcastle disease (ND) is a highly contagious disease that affects many species of birds and causes significant economic losses to the poultry industry worldwide. Fifteen Newcastle disease virus (NDV) isolates obtained from rural chickens in northwest Ethiopia in 2011 and 2012 were characterized genotypically. The main functional region of the F gene was amplified and sequenced (260 nucleotides). Among the Ethiopian NDV isolates, 2 isolates had the virulent motif (112)R-R-Q-K-R-F(117) at the cleavage site of the fusion protein while 13 isolates contained the lentogenic motif (112)G-G/R-Q-G-R-L(117). Phylogenetic analysis based on the variable region of the F gene indicated that the two isolates exhibiting the virulent motif belonged to lineage 5 (genotype VII) subgenotype d and the remaining 13 isolates were grouped into lineage 2 (genotype II). The nucleotide sequences of lineage 5 isolates were genetically related to the Sudanese NDV isolates, suggesting potential epidemiological link of ND outbreaks between neighbouring countries. The lentogenic strains shared similarities with La Sota vaccine strain and probably originated from the vaccine strain either through direct exposure of birds to the live vaccine or to infectious La Sota-like strains circulating in rural poultry. This study provides genetic evidence on the existence of different NDV genotypes circulating in the rural poultry in Ethiopia. The virulent NDV continues to be a problem in poultry sector in Ethiopia, and their continuous circulation in rural and commercial poultry calls for improved surveillance and intensified vaccination and other control measures.


Assuntos
Galinhas , Genótipo , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Sequência de Aminoácidos , Animais , Surtos de Doenças/veterinária , Etiópia/epidemiologia , Regulação Viral da Expressão Gênica , Doença de Newcastle/epidemiologia , Doença de Newcastle/prevenção & controle , Filogenia , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/metabolismo , Vacinas Virais/imunologia
20.
J Virol ; 86(8): 4370-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22345462

RESUMO

Influenza viruses of gallinaceous poultry and wild aquatic birds usually have distinguishable receptor-binding properties. Here we used a panel of synthetic sialylglycopolymers and solid-phase receptor-binding assays to characterize receptor-binding profiles of about 70 H7 influenza viruses isolated from aquatic birds, land-based poultry, and horses in Eurasia and America. Unlike typical duck influenza viruses with non-H7 hemagglutinin (HA), all avian H7 influenza viruses, irrespective of the host species, displayed a poultry-virus-like binding specificity, i.e., preferential binding to sulfated oligosaccharides Neu5Acα2-3Galß1-4(6-O-HSO(3))GlcNAc and Neu5Acα2-3Galß1-4(Fucα1-3)(6-O-HSO(3))GlcNAc. This phenotype correlated with the unique amino acid sequence of the amino acid 185 to 189 loop of H7 HA and seemed to be dependent on ionic interactions between the sulfate group of the receptor and Lys193 and on the lack of sterical clashes between the fucose residue and Gln222. Many North American and Eurasian H7 influenza viruses displayed weak but detectable binding to the human-type receptor moiety Neu5Acα2-6Galß1-4GlcNAc, highlighting the potential of H7 influenza viruses for avian-to-human transmission. Equine H7 influenza viruses differed from other viruses by preferential binding to the N-glycolyl form of sialic acid. Our data suggest that the receptor-binding site of contemporary H7 influenza viruses in aquatic and terrestrial birds was formed after the introduction of their common precursor from ducks to a new host, presumably, gallinaceous poultry. The uniformity of the receptor-binding profile of H7 influenza viruses in various wild and domestic birds indicates that there is no strong receptor-mediated host range restriction in birds on viruses with this HA subtype. This notion agrees with repeated interspecies transmission of H7 influenza viruses from aquatic birds to poultry.


Assuntos
Especificidade de Hospedeiro , Vírus da Influenza A/metabolismo , Receptores Virais/metabolismo , Sequência de Aminoácidos , Animais , Aves , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Modelos Moleculares , Dados de Sequência Molecular , Ácidos Neuramínicos/imunologia , Ácidos Neuramínicos/metabolismo , Filogenia , Ligação Proteica/fisiologia , Conformação Proteica , Receptores Virais/química , Alinhamento de Sequência
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