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1.
Viruses ; 13(10)2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34696406

RESUMO

Coronaviruses (CoVs) are a group of enveloped positive-sense RNA viruses and can cause deadly diseases in animals and humans. Cell entry is the first and essential step of successful virus infection and can be divided into two ongoing steps: cell binding and membrane fusion. Over the past two decades, stimulated by the global outbreak of SARS-CoV and pandemic of SARS-CoV-2, numerous efforts have been made in the CoV research. As a result, significant progress has been achieved in our understanding of the cell entry process. Here, we review the current knowledge of this essential process, including the viral and host components involved in cell binding and membrane fusion, molecular mechanisms of their interactions, and the sites of virus entry. We highlight the recent findings of host restriction factors that inhibit CoVs entry. This knowledge not only enhances our understanding of the cell entry process, pathogenesis, tissue tropism, host range, and interspecies-transmission of CoVs but also provides a theoretical basis to design effective preventive and therapeutic strategies to control CoVs infection.


Assuntos
Infecções por Coronavirus/patologia , Coronavirus/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Ligação Viral , Internalização do Vírus , Animais , Gatos/virologia , Bovinos/virologia , Galinhas/virologia , Coronavirus/genética , Cães/virologia , Gado/virologia , Fusão de Membrana/fisiologia , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Suínos/virologia , Tropismo Viral/fisiologia
2.
Arch Virol ; 166(11): 3093-3103, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34480638

RESUMO

Infectious bronchitis (IB) is a highly contagious respiratory disease caused by a gammacoronavirus that has been circulating for many years in chickens in Bangladesh, resulting in significant economic losses. The aim of this study was to detect and characterize infectious bronchitis virus (IBV) from clinical outbreaks and surveillance samples. Real-time RT-PCR was used to detect IBV in pooled lung and tracheal tissue samples (n = 78), oropharyngeal swabs (n = 19), and pooled fecal samples (n = 13) from live-bird markets. Both respiratory and nephropathogenic forms of IB were suspected at necropsy (n = 7) from clinical outbreaks. Sequencing of hypervariable regions (HVR1-2 and HVR3) of the region of the spike gene (S) encoding the S1 subunit of five isolates revealed circulation of the Mass-like, QX-like, and 4/91-like genotypes of IBV in Bangladesh. Each genotype was extremely variable, as shown by separate clustering of the viruses in a phylogenetic tree and high nucleotide (nt) sequence divergence (38.8-41.2% and 25.7-37.4% in the HVR1-2 and HVR3 sequence, respectively). The unique mutation G65E was observed in each Mass-like isolate, and Y328S was observed in each 4/91-like Bangladeshi isolate. Three neutralizing epitope sites were predicted within the HVRs that differed significantly among the three genotypes. In addition, one Bangladeshi isolate carried fixed mutations at 294F and 306Y, like other pathogenic QX-like IBVs, which could affect epitopes involved in neutralization, facilitating virus circulation among vaccinated flocks. Therefore, continuous screening and genotype characterization will be necessary to track the epidemiology of IBV and control IB infection in Bangladesh.


Assuntos
Galinhas/virologia , Infecções por Coronavirus/veterinária , Epitopos/genética , Vírus da Bronquite Infecciosa/genética , Doenças das Aves Domésticas/virologia , Animais , Bangladesh/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Surtos de Doenças , Epitopos/química , Genótipo , Rim/patologia , Rim/virologia , Mortalidade , Mutação , Filogenia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/etiologia , Glicoproteína da Espícula de Coronavírus/genética
3.
Virus Res ; 306: 198566, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34582833

RESUMO

Coronavirus disease 2019 (COVID-19), caused by Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was first reported in Wuhan, China, and rapidly spread throughout the world. This newly emerging pathogen is highly transmittable and can cause fatal disease. More than 35 million cases have been confirmed, with a fatality rate of about 2.9% to October 9, 2020. However, the original and intermediate hosts of SARS-CoV-2 remain unknown. Here, 3160 poultry samples collected from 14 provinces of China between September and December 2019 were tested for SARS-CoV-2 infection. All the samples were SARS-CoV-2 negative, but 593 avian coronaviruses were detected, including 485 avian infectious bronchitis viruses, 72 duck coronaviruses, and 36 pigeon coronaviruses, with positivity rates of 15.35%, 2.28%, and 1.14%, respectively. Our surveillance demonstrates the diversity of avian coronaviruses in China, with higher prevalence rates in some regions. Furthermore, the possibility that SARS-CoV-2 originated from a known avian-origin coronavirus can be preliminarily ruled out. More surveillance of and research into avian coronaviruses are required to better understand the diversity, distribution, cross-species transmission, and clinical significance of these viruses.


Assuntos
Doenças das Aves/virologia , Infecções por Coronavirus/veterinária , Coronavirus/genética , Coronavirus/isolamento & purificação , Variação Genética , Animais , Doenças das Aves/epidemiologia , Galinhas/virologia , China/epidemiologia , Columbidae/virologia , Coronavirus/classificação , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Patos/virologia , Monitoramento Epidemiológico , Gansos/virologia , Filogenia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação
4.
Int J Mol Sci ; 22(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34445163

RESUMO

Mammalian cells utilize a wide spectrum of pathways to antagonize the viral replication. These pathways are typically regulated by antiviral proteins and can be constitutively expressed but also exacerbated by interferon induction. A myriad of interferon-stimulated genes (ISGs) have been identified in mounting broad-spectrum antiviral responses. Members of the interferon-induced transmembrane (IFITM) family of proteins are unique among these ISGs due to their ability to prevent virus entry through the lipid bilayer into the cell. In the current study, we generated transgenic chickens that constitutively and stably expressed chicken IFITM1 (chIFITM1) using the avian sarcoma-leukosis virus (RCAS)-based gene transfer system. The challenged transgenic chicks with clinical dose 104 egg infective dose 50 (EID50) of highly pathogenic avian influenza virus (HPAIV) subtype H5N1 (clade 2.2.1.2) showed 100% protection and significant infection tolerance. Although challenged transgenic chicks displayed 60% protection against challenge with the sub-lethal dose (EID50 105), the transgenic chicks showed delayed clinical symptoms, reduced virus shedding, and reduced histopathologic alterations compared to non-transgenic challenged control chickens. These finding indicate that the sterile defense against H5N1 HPAIV offered by the stable expression of chIFITM1 is inadequate; however, the clinical outcome can be substantially ameliorated. In conclusion, chIFITM proteins can inhibit influenza virus replication that can infect various host species and could be a crucial barrier against zoonotic infections.


Assuntos
Antígenos de Diferenciação/genética , Proteínas Aviárias/genética , Galinhas/genética , Virus da Influenza A Subtipo H5N1/fisiologia , Influenza Aviária/genética , Animais , Animais Geneticamente Modificados/genética , Galinhas/virologia , Técnicas de Transferência de Genes , Influenza Aviária/patologia , Influenza Aviária/virologia
5.
Avian Dis ; 65(3): 364-372, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34427409

RESUMO

We previously reported that recombinant Newcastle disease virus LaSota (rLS) expressing infectious bronchitis virus (IBV) Arkansas (Ark)-type trimeric spike (S) ectodomain (Se; rLS/ArkSe) provides suboptimal protection against IBV challenge. We have now developed rLS expressing chicken granulocyte-macrophage colony-stimulating factor (GMCSF) and IBV Ark Se in an attempt to enhance vaccine effectiveness. In the current study, we first compared protection conferred by vaccination with rLS/ArkSe and rLS/ArkSe.GMCSF. Vaccinated chickens were challenged with virulent Ark, and protection was determined by clinical signs, viral load, and tracheal histomorphometry. Results showed that coexpression of GMCSF and the Se from rLS significantly reduced tracheal viral load and tracheal lesions compared with chickens vaccinated with rLS/ArkSe. In a second experiment, we evaluated enhancement of cross-protection of a Massachusetts (Mass) attenuated vaccine by priming or boosting with rLS/ArkSe.GMCSF. Vaccinated chickens were challenged with Ark, and protection was evaluated. Results show that priming or boosting with the recombinant virus significantly increased cross-protection conferred by Mass against Ark virulent challenge. Greater reductions of viral loads in both trachea and lachrymal fluids were observed in chickens primed with rLS/ArkSe.GMCSF and boosted with Mass. Consistently, Ark Se antibody levels measured with recombinant Ark Se protein-coated ELISA plates 14 days after boost were significantly higher in these chickens. Unexpectedly, the inverse vaccination scheme, that is, priming with Mass and boosting with the recombinant vaccine, proved somewhat less effective. We concluded that a prime and boost strategy by using rLS/ArkSe.GMCSF and the worldwide ubiquitous Mass attenuated vaccine provides enhanced cross-protection. Thus, rLS/GMCSF coexpressing the Se of regionally relevant IBV serotypes could be used in combination with live Mass to protect against regionally circulating IBV variant strains.


Assuntos
Infecções por Coronavirus/veterinária , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Vírus da Bronquite Infecciosa/imunologia , Vírus da Doença de Newcastle/genética , Doenças das Aves Domésticas/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Animais , Anticorpos Antivirais/imunologia , Galinhas/genética , Galinhas/imunologia , Galinhas/virologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Proteção Cruzada , Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Vírus da Bronquite Infecciosa/química , Vírus da Bronquite Infecciosa/genética , Vírus da Bronquite Infecciosa/fisiologia , Vírus da Doença de Newcastle/metabolismo , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Domínios Proteicos , Glicoproteína da Espícula de Coronavírus/administração & dosagem , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Traqueia/imunologia , Traqueia/virologia , Vacinação , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Carga Viral
6.
Avian Dis ; 65(2): 219-226, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34412451

RESUMO

Movement and land application of manure is a known risk factor for secondary spread of avian influenza viruses. During an outbreak of highly pathogenic avian influenza (HPAI), movement of untreated (i.e., fresh) manure from premises known to be infected is prohibited. However, moving manure from apparently healthy (i.e., clinically normal) flocks may be critical, because some egg-layer facilities have limited on-site storage capacity. The objective of this analysis was to evaluate targeted dead-bird active surveillance real-time reverse transcriptase polymerase chain reaction (rRT-PCR) testing protocols that could be used for the managed movement of manure from apparently healthy egg-layer flocks located in an HPAI control area. We also evaluated sequestration, which is the removal of manure from any contact with chickens, or with manure from other flocks, for a period of time, while the flock of origin is actively monitored for the presence of HPAI virus. We used stochastic simulation models to predict the chances of moving a load of contaminated manure, and the quantity of HPAI virus in an 8 metric ton (8000 kg) load of manure moved, before HPAI infection could be detected in the flock. We show that the likelihood of moving contaminated manure decreases as the length of the sequestration period increases from 3 to 10 days (e.g., for a typical contact rate, with a sample pool size of 11 swabs, the likelihood decreased from 48% to <1%). The total quantity of feces from HPAI-infectious birds in a manure load moved also decreases. Results also indicate that active surveillance protocols using 11 swabs per pool result in a lower likelihood of moving contaminated manure relative to protocols using five swabs per pool. Simulation model results from this study are useful to inform further risk evaluation of HPAI spread through pathways associated with manure movement and further evaluation of biosecurity measures intended to reduce those risks.


Assuntos
Galinhas/virologia , Vírus da Influenza A/patogenicidade , Influenza Aviária/transmissão , Esterco/virologia , Eliminação de Resíduos de Serviços de Saúde/métodos , Animais , Simulação por Computador , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/prevenção & controle , Eliminação de Resíduos de Serviços de Saúde/normas , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Processos Estocásticos
7.
Genes (Basel) ; 12(6)2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200798

RESUMO

Highly pathogenic avian influenza viruses (HPAIVs) in gallinaceous poultry are associated with viral infection of the endothelium, the induction of a 'cytokine storm, and severe disease. In contrast, in Pekin ducks, HPAIVs are rarely endothelial tropic, and a cytokine storm is not observed. To date, understanding these species-dependent differences in pathogenesis has been hampered by the absence of a pure culture of duck and chicken endothelial cells. Here, we use our recently established in vitro cultures of duck and chicken aortic endothelial cells to investigate species-dependent differences in the response of endothelial cells to HPAIV H5N1 infection. We demonstrate that chicken and duck endothelial cells display a different transcriptional response to HPAI H5N1 infection in vitro-with chickens displaying a more pro-inflammatory response to infection. As similar observations were recorded following in vitro stimulation with the viral mimetic polyI:C, these findings were not specific to an HPAIV H5N1 infection. However, similar species-dependent differences in the transcriptional response to polyI:C were not observed in avian fibroblasts. Taken together, these data demonstrate that chicken and duck endothelial cells display a different response to HPAIV H5N1 infection, and this may help account for the species-dependent differences observed in inflammation in vivo.


Assuntos
Galinhas/imunologia , Patos/imunologia , Células Endoteliais/virologia , Virus da Influenza A Subtipo H5N1/patogenicidade , Animais , Células Cultivadas , Galinhas/virologia , Citocinas/genética , Citocinas/metabolismo , Patos/virologia , Células Endoteliais/imunologia , Endotélio Vascular/citologia , Especificidade da Espécie , Transcriptoma
8.
Vet Microbiol ; 260: 109094, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34271302

RESUMO

In mid-2020, using next-generation sequencing (NGS) technology, we identified a recombinant cluster 2 avian orthoreovirus (ARV) variant named PHC-2020-0545, isolated from tendons of 33-day-old broilers with leg swelling in China. Complete genomic sequencing and analyses demonstrated that the isolate was genetically significantly distinct from known ARV strains in M1 and M3 genes and its σC coding gene had an extremely high variability, compared with the identified ARV strains grouped into other genotyping cluster. Further analysis showed that many base substitutions were silent and non-silent substitutions are most likely to occur in the first positions of codons. Multiple segmental recombination, intra-segmental recombination and accumulation of point mutations might contribute to the emergence of this isolate. The PHC-2020-0545 strain had a strong replication ability in 1-day-old broilers, and mainly affected the movement, digestion and metabolism of broilers. In addition, the infection route of the isolate is related to its pathogenicity to broilers. Therefore, combined with its unique genetic characteristics and potential origin, we determined that the PHC-2020-0545 field strain is a novel recombinant ARV strain, which has certain reference value for the preparation and evaluation of new vaccines.


Assuntos
Galinhas/virologia , Genoma Viral/genética , Orthoreovirus Aviário/genética , Doenças das Aves Domésticas/virologia , Recombinação Genética , Infecções por Reoviridae/veterinária , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , China , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Masculino , Mutação , Orthoreovirus Aviário/patogenicidade , Filogenia , Infecções por Reoviridae/virologia , Alinhamento de Sequência/veterinária
9.
Vet Microbiol ; 260: 109180, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34271303

RESUMO

H2N2 subtype low pathogenic avian influenza viruses (LPAIVs) have persisted in live bird markets (LBMs) in the Northeastern United States since 2014. Although unrelated to the 1957 pandemic H2N2 lineage, there is concern that the virus could have animal and public health consequences because of high contact with humans and numerous species in the LBM system. The pathogenicity, infectivity, and transmissibility of six LBM H2N2 viruses isolated from three avian species in LBMs were examined in chickens. Two of these isolates were also tested in Pekin ducks and guinea fowl. Full genome sequence was obtained from all 6 isolates and evaluated for genetic markers for host adaptation and pathogenicity in poultry. Clinical signs were not observed in any host with any of the isolates, however one recent isolate was shed at higher titers than the other isolates and had the lowest bird infectious dose of all the isolates tested in all three species. This isolate, A/chicken/NY/19-012787-1/2019, was also the only isolate with a deletion in the stalk region of the neuraminidase protein (NA). This supports the theory that the NA stalk deletion is evidence of adaptation to gallinaceous poultry.


Assuntos
Galinhas/virologia , Patos/virologia , Genoma Viral/genética , Vírus da Influenza A Subtipo H2N2/patogenicidade , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Animais , Vírus da Influenza A Subtipo H2N2/genética , Vírus da Influenza A Subtipo H2N2/fisiologia , Influenza Aviária/transmissão , Doenças das Aves Domésticas/transmissão , Virulência
10.
Sci Rep ; 11(1): 13786, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215796

RESUMO

Virus-like particles (VLPs) are recognized as an alternative vaccine platform that provide effective protection against various highly pathogenic avian influenza viruses (HPAIVs). Here, we developed multi-clade VLPs expressing two HAs (a chimera of clade 2.3.2.1c and clade 2.3.4.4c HA) within a single vector. We then compared its protective efficacy with that of a monovalent VLP and evaluated its potency against each homologous strain. Chickens vaccinated with the multi-clade VLP shed less virus and were better protected against challenge than birds receiving monovalent vaccines. Single vaccination with a multi-clade VLP resulted in 100% survival, with no clinical symptoms and high levels of pre-challenge protective immunity (7.6-8.5 log2). Moreover, the multi-clade VLP showed high productivity (128-256 HAU) both in the laboratory and on a large scale, making it cheaper than whole inactivated vaccines produced in eggs. However, the PD50 (protective dose 50%) of the multi-clade VLP against clades 2.3.2.1c and 2.3.4.4c was < 50 PD50 (28 and 42 PD50, respectively), and effective antibody response was maintained for 2-3 months. This multi-clade VLP protects against both clades of HPAI viruses and can be produced in high amounts at low cost. Thus, the vaccine has potential as a pandemic preparedness vaccine.


Assuntos
Vírus da Influenza A/patogenicidade , Vacinas contra Influenza/farmacologia , Influenza Aviária/tratamento farmacológico , Vacinas de Partículas Semelhantes a Vírus/farmacologia , Animais , Galinhas/virologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A/efeitos dos fármacos , Influenza Aviária/patologia , Influenza Aviária/virologia , Vacinas de Produtos Inativados/farmacologia
11.
Res Vet Sci ; 139: 166-171, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34332419

RESUMO

There are currently no vaccines or effective drugs to prevent the disorders caused by avian leukosis virus subgroup J (ALV-J). Hence, it is critical to identify potential biomarkers in ALV-J-infected chickens to prevent ALV-J-induced disorders. We hypothesized that ALV-J infection alters metabolic profile in chickens. In the present study, a nontargeted metabolomics approach based on liquid chromatography coupled with mass spectrometry (LC-MS) was used to find differential metabolites in plasma samples from ALV-J-infected chickens and healthy controls. The parametric statistical test (Student's t-test) and fold change analysis were used for univariate analysis. Multivariate statistical analyses included principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). The levels of methyl bromide, pyraclonil, hexaflumuron, lythidathion, 3-phosphoglycerol-glutathione, bis-4-nitrophenyl phosphate, 4-ketocyclophosphamide, oxidized photinus luciferin, phenyl sulfate, and aryl sulfate significantly decreased, whereas the levels of 2-methylthiobenzothiazole, irinotecan, methadone, 3-o-ethyl-l-ascorbic acid, and o-acetylneuraminic acid markedly increased in ALV-J-infected chickens as compared to those in healthy controls. These data provide metabolic evidence and potential biomarkers for ALV-J-induced alterations in plasma metabolism.


Assuntos
Vírus da Leucose Aviária , Leucose Aviária , Galinhas , Metabolômica , Doenças das Aves Domésticas , Animais , Biomarcadores , Galinhas/metabolismo , Galinhas/virologia
12.
Vet Microbiol ; 260: 109184, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34311270

RESUMO

Avian leukosis virus (ALV) can induce various tumors and cause serious production problems. ALVs isolated from chickens were divided into six subgroups (A-J). In 2012, a strain of a putative novel subgroup of ALVs was isolated from Chinese native chickens in Jiangsu Province and named as ALV-K. In this study, three ALV-K strains (JS14LH01, JS13LH14, and JS15SG01) were isolated from chickens with suspected ALV infection in Jiangsu Province. Their complete genomes were amplified, sequenced, and analyzed systematically. The results showed that JS14LH01 and JS13LH14 were ALV-K and ALV-E recombinant strains. Whereas JS15SG01 is an ALV-K, ALV-E, and ALV-J multiple recombinant strain containing the U3 region of ALV-J. The pathogenicity test of JS15SG01 revealed that, compared with previous ALV-K strains, the viremia and viral shedding level of JS15SG01-infected chickens were significantly increased, reaching 100 % and 59 %, respectively. More important, JS15SG01 induced significant proliferation of gliocytes in the cerebral cortex of infected chickens, accompanied by the neurotropic phenomenon. This is the first report about a multiple recombinant ALV-K strain that could invade and injure the brain tissue of chickens in China. Our findings enriched the epidemiologic data of ALV and helped to reveal the evolution of ALV strains prevalent in chicken fields.


Assuntos
Vírus da Leucose Aviária/genética , Leucose Aviária/virologia , Galinhas/virologia , Recombinação Genética , Animais , Leucose Aviária/epidemiologia , Vírus da Leucose Aviária/isolamento & purificação , Vírus da Leucose Aviária/patogenicidade , China
13.
Vet Microbiol ; 260: 109151, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34237662

RESUMO

Avian infectious bronchitis virus (IBV), belonging to Gammacoronavirus, is an economically important respiratory virus affecting poultry industry worldwide. The virus can infect chickens at all ages, whereas young chickens (less than 15 day old) are more susceptible to it. The present study was conducted to investigate effects of dietary supplementation of black soldier fly (Hermetia illucens L.) larvae (BSFL) on immune responses in IBV infected 10-day-old chickens. BSFL were ground to powder and mixed with commercial fodder (1%, 5%, and 10 % [mass] BSFL powder) to feed 1-day-old yellow broilers for ten days and then challenged with IBV. Our results indicated that commercial fodder supplemented with 10 % BSFL [mass] reduced mortalities (20 %) and morbidities (80 %), as well as IBV viral loads in tracheas (65.8 %) and kidneys (20.4 %) from 3-day post challenge (dpc), comparing to that of IBV-infected chickens fed with non-additive commercial fodder. Furthermore, at 3-day post challenge (dpc), 10 % BSFL [mass] supplemented chickens presented more CD8+ T lymphocytes in peripheral blood and a rise in interferon-g (IFN-γ) at both mRNA and protein levels in spleens, comparing with chickens fed with commercial fodder. Furthermore, the mRNA abundance of MHC-I, Fas, LITAF, and IL-2 in the spleens of 10 % BSFL [mass] supplemented chickens increased at different time points after challenge. The present results suggest that supplemental BSFL could improve CD8+ T lymphocytes proliferation, thus benefit young chickens to defend against IBV infection.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Galinhas/fisiologia , Infecções por Coronavirus/veterinária , Dípteros/fisiologia , Vírus da Bronquite Infecciosa/imunologia , Doenças das Aves Domésticas/dietoterapia , Ração Animal/análise , Animais , Linfócitos T CD8-Positivos/citologia , Galinhas/imunologia , Galinhas/virologia , Infecções por Coronavirus/dietoterapia , Infecções por Coronavirus/imunologia , Dieta/veterinária , Vírus da Bronquite Infecciosa/genética , Larva , Masculino , Doenças das Aves Domésticas/imunologia
14.
Vet Microbiol ; 259: 109082, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34144834

RESUMO

MicroRNAs (miRNAs) are a class of ∼22 nucleotides non-coding RNAs that are encoded by a wide range of hosts. Viruses, especially herpesviruses, encode a variety of miRNAs that involved in disease progression. Recently, a cluster of virus-encoded miRNAs, miR-M8-M10, have been shown to restrict early cytolytic replication and pathogenesis of Marek's disease virus (MDV), an oncogenic avian alphaherpesvirus that causes lymphoproliferative disease in chickens. In this study, we specifically dissected the role of miR-M7, a member of cluster miR-M8-M10, in regulating MDV replication and pathogenesis. We found that deletion of miR-M7-5p did not affect the virus plaque size and growth in cell culture. However, compared to parental virus, infection of miR-M7-5p deletion virus significantly increased MDV genome copy number at 5 days post infection, suggesting that miR-M7 plays a role to restrict MDV replication during early cytolytic phase. In addition, our results showed that infection of miR-M7-5p deletion virus significantly enhanced the mortality of chickens, even it induced lymphoid organ atrophy similar to parental and revertant viruses. Taken together, our study revealed that the miR-M7 acts as a repressive factor of MDV replication and pathogenesis.


Assuntos
Herpesvirus Galináceo 2/genética , Herpesvirus Galináceo 2/patogenicidade , MicroRNAs/genética , Proteínas Virais/genética , Replicação Viral/genética , Animais , Células Cultivadas , Galinhas/virologia , Fibroblastos/virologia , Deleção de Genes , Herpesvirus Galináceo 2/crescimento & desenvolvimento , Doença de Marek/virologia , Organismos Livres de Patógenos Específicos , Fatores de Virulência/genética
15.
Vet Microbiol ; 259: 109101, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34166888

RESUMO

Mycoplasma synoviae is a common pathogen affecting poultry and has important economic significance. Infectious synovitis is the most common clinical effect. Since 2010, the incidence of M. synoviae infection in China has rapidly risen, causing significant economic losses to the chicken industry; however, the cause of the disease outbreak remains unclear. Phylogenetic and evolutionary analyses of field strains will help unravel the mystery. The multi-locus sequence typing (MLST) method is typically utilized to conduct genotyping and traceability analysis of microorganisms. MLST of M. synoviae has previously been established and shown strong discriminatory power. In this study, 54 Chinese M. synoviae strains isolated from 2016 to 2020 were genotyped by MLST based on seven housekeeping genes. This study aimed to investigate the dominant genotypes of M. synoviae in China and reveal the genetic and evolutionary relationships of these isolates. All 54 isolates were found to have new allelic sequences, which may indicate new sequence types. The results of BURST analysis indicated that all 54 strains belonged to group 11, which is an independent phylogenetic branch, and were separated from any other reference strains (189 isolates) in the PubMLST database. In conclusion, the results of this study suggest that the M. synoviae strains circulating in China are relatively independent in terms of transmission and evolutionary relationships.


Assuntos
Tipagem de Sequências Multilocus/métodos , Infecções por Mycoplasma/veterinária , Mycoplasma synoviae/classificação , Mycoplasma synoviae/genética , Filogenia , Animais , Proteínas de Bactérias/genética , Galinhas/virologia , China , Genótipo , Infecções por Mycoplasma/microbiologia , Aves Domésticas/virologia , Doenças das Aves Domésticas/microbiologia , Análise de Sequência de DNA
16.
J Virol ; 95(17): e0060321, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34133902

RESUMO

Since 2015, severe hydropericardium-hepatitis syndrome (HHS) associated with a novel fowl adenovirus 4 (FAdV-4) has emerged in China, representing a new challenge for the poultry industry. Although various highly pathogenic FAdV-4 strains have been isolated, the virulence factor and the pathogenesis of novel FAdV-4 are unclear. In our previous studies, we reported that a large genomic deletion (1,966 bp) is not related to increased virulence. Here, two recombinant chimeric viruses, rHN20 strain and rFB2 strain, were generated from a highly pathogenic FAdV-4 strain by replacing the hexon or fiber-2 gene of a nonpathogenic FAdV-4, respectively. Both chimeric strains showed similar titers to the wild-type strain in vitro. Notably, rFB2 and the wild-type strain induced 100% mortality, while no mortality or clinical signs appeared in chickens inoculated with rHN20, indicating that hexon, but not fiber-2, determines the novel FAdV-4 virulence. Furthermore, an R188I mutation in the hexon protein identified residue 188 as the key amino acid for the reduced pathogenicity. The rR188I mutant strain was significantly neutralized by chicken serum in vitro and in vivo, whereas the wild-type strain was able to replicate efficiently. Finally, the immunogenicity of the rescued rR188I was investigated. Nonpathogenic rR188I provided full protection against lethal FAdV-4 challenge. Collectively, these findings provide an in-depth understanding of the molecular basis of novel FAdV-4 pathogenicity and present rR188I as a potential live attenuated vaccine candidate or a novel vaccine vector for HHS vaccines. IMPORTANCE HHS associated with a novel FAdV-4 infection in chickens has caused huge economic losses to the poultry industry in China since 2015. The molecular basis for the increased virulence remains largely unknown. Here, we demonstrate that the hexon gene is vital for FAdV-4 pathogenicity. Furthermore, we show that the amino acid residue at position 188 of the hexon protein is responsible for pathogenicity. Importantly, the rR188I mutant strain was neutralized by chicken serum in vitro and in vivo, whereas the wild-type strain was not. Further, the rR188I mutant strain provided complete protection against FAdV-4 challenge. Our results provide a molecular basis of the increased virulence of novel FAdV-4. We propose that the rR188I mutant is a potential live attenuated vaccine against HHS and a new vaccine vector for HHS-combined vaccines.


Assuntos
Infecções por Adenoviridae/veterinária , Aviadenovirus/patogenicidade , Proteínas do Capsídeo/metabolismo , Galinhas/virologia , Mutação , Doenças das Aves Domésticas/virologia , Proteínas Virais/metabolismo , Infecções por Adenoviridae/virologia , Substituição de Aminoácidos , Animais , Aviadenovirus/classificação , Aviadenovirus/genética , Aviadenovirus/isolamento & purificação , Proteínas do Capsídeo/genética , Proteínas Virais/genética , Virulência
17.
BMC Vet Res ; 17(1): 210, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34098961

RESUMO

BACKGROUND: The poultry industry in Egypt has been suffering from endemic highly pathogenic avian influenza (HPAI) virus, subtype H5N1 since 2006. However, the emergence of H9N2, H5N8, and H5N2 in 2011, 2016, and 2019 respectively, has aggravated the situation. Our objective was to evaluate how effective are the mitigation strategies by a Quantitative Risk Assessment (QRA) model which used daily outbreak data of HPAI-H5N1 subtype in Egypt, stratified by different successive epidemic waves from 2006 to 2016. RESULTS: By applying the epidemiologic problem-oriented approach methodology, a conceptual scenario tree was drawn based on the knowledgebase. Monte Carlo simulations of QRA parameters based on outbreak data were performed using @Risk software based on a scenario-driven decision tree. In poultry farms, the expected probability of HPAI H5N1 prevalence is 48% due to failure of mitigation strategies in 90% of the time during Monte Carlo simulations. Failure of efficacy of these mitigations will raise prevalence to 70% with missed vaccination, while failure in detection by surveillance activities will raise it to 99%. In backyard poultry farms, the likelihood of still having a high HPAI-H5N1 prevalence in different poultry types due to failure of passive and active surveillance varies between domestic, mixed and reservoir. In mixed poultry, the probability of HPAI-H5N1 not detected by surveillance was the highest with a mean and a SD of 16.8 × 10-3 and 3.26 × 10-01 respectively. The sensitivity analysis ranking for the likelihood of HPAI-H5N1 in poultry farms due to missed vaccination, failure to be detected by passive and active surveillance was examined. Among poultry farms, increasing vaccination by 1 SD will decrease the prevalence by 14%, while active and passive surveillance decreases prevalence by 12, and 6%, respectively. In backyard, the active surveillance had high impact in decreasing the prevalence by 16% in domestic chicken. Whereas the passive surveillance had less impact in decreasing prevalence by 14% in mixed poultry and 3% in domestic chicken. CONCLUSION: It could be concluded that the applied strategies were not effective in controlling the spread of the HPAI-H5N1 virus. Public health officials should take into consideration the evaluation of their control strategies in their response.


Assuntos
Galinhas , Virus da Influenza A Subtipo H5N1 , Vacinas contra Influenza/administração & dosagem , Influenza Aviária/prevenção & controle , Doenças das Aves Domésticas/prevenção & controle , Animais , Galinhas/virologia , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Egito/epidemiologia , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Modelos Biológicos , Método de Monte Carlo , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia , Prevalência , Medição de Risco
18.
Mol Cells ; 44(6): 377-383, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34187969

RESUMO

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is a novel virus that causes coronavirus disease 2019 (COVID-19). To understand the identity, functional characteristics and therapeutic targets of the virus and the diseases, appropriate infection models that recapitulate the in vivo pathophysiology of the viral infection are necessary. This article reviews the various infection models, including Vero cells, human cell lines, organoids, and animal models, and discusses their advantages and disadvantages. This knowledge will be helpful for establishing an efficient system for defense against emerging infectious diseases.


Assuntos
COVID-19/virologia , Modelos Teóricos , Organoides/virologia , SARS-CoV-2/patogenicidade , Animais , COVID-19/imunologia , COVID-19/patologia , Gatos , Linhagem Celular Tumoral , Galinhas/virologia , Chlorocebus aethiops/virologia , Cricetinae , Cães , Furões/virologia , Humanos , Camundongos , Organoides/imunologia , Organoides/patologia , Coelhos , SARS-CoV-2/crescimento & desenvolvimento , Suínos/virologia , Células Vero
19.
Int J Mol Sci ; 22(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063782

RESUMO

In this study, we demonstrate the synthesis of carbonized nanogels (CNGs) from an amino acid (lysine hydrochloride) using a simple pyrolysis method, resulting in effective viral inhibition properties against infectious bronchitis virus (IBV). The viral inhibition of CNGs was studied using both in vitro (bovine ephemeral fever virus (BEFV) and pseudorabies virus (PRV)) and in ovo (IBV) models, which indicated that the CNGs were able to prevent virus attachment on the cell membrane and penetration into the cell. A very low concentration of 30 µg mL-1 was found to be effective (>98% inhibition) in IBV-infected chicken embryos. The hatching rate and pathology of IBV-infected chicken embryos were greatly improved in the presence of CNGs. CNGs with distinctive virus-neutralizing activities show great potential as a virostatic agent to prevent the spread of avian viruses and to alleviate the pathology of infected avian species.


Assuntos
Antivirais/farmacologia , Infecções por Coronavirus/tratamento farmacológico , Vírus da Bronquite Infecciosa/efeitos dos fármacos , Lisina/farmacologia , Nanogéis/administração & dosagem , Substâncias Protetoras/farmacologia , Animais , Linhagem Celular , Galinhas/virologia , Chlorocebus aethiops , Infecções por Coronavirus/virologia , Cricetinae , Vírus da Febre Efêmera Bovina/efeitos dos fármacos , Feminino , Herpesvirus Suídeo 1/efeitos dos fármacos , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/virologia , Ratos , Ratos Sprague-Dawley , Células Vero , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
20.
PLoS One ; 16(5): e0251841, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34038460

RESUMO

Outbreaks of avian influenza virus (AIV) infection included the spread of highly pathogenic AIV in commercial poultry and backyard flocks in the spring of 2015. This resulted in estimated losses of more than $8.5 million from federal government expenditures, $1.6 billion from direct losses to produces arising from destroyed turkey and chicken egg production, and economy-wide indirect costs of $3.3 billion from impacts on retailers and the food service industries. Additionally, these outbreaks resulted in the death or depopulation of nearly 50 million domestic birds. Domesticated male ferrets (Mustela putorius furo) were trained to display a specific conditioned behavior (i.e. active scratch alert) in response to feces from AIV-infected mallards in comparison to feces from healthy ducks. In order to establish that ferrets were identifying samples based on odors associated with infection, additional experiments controlled for potentially confounding effects, such as: individual duck identity, housing and feed, inoculation concentration, and day of sample collection (post-infection). A final experiment revealed that trained ferrets could detect AIV infection status even in the presence of samples from mallards inoculated with Newcastle disease virus or infectious laryngotracheitis virus. These results indicate that mammalian biodetectors are capable of discriminating the specific odors emitted from the feces of non-infected versus AIV infected mallards, suggesting that the health status of waterfowl can be evaluated non-invasively for AIV infection via monitoring of volatile fecal metabolites. Furthermore, in situ monitoring using trained biodetectors may be an effective tool for assessing population health.


Assuntos
Patos/virologia , Furões/fisiologia , Influenza Aviária/diagnóstico , Odorantes/análise , Animais , Galinhas/virologia , Fezes/virologia , Humanos , Vírus da Influenza A/patogenicidade , Influenza Aviária/virologia , Aves Domésticas/virologia , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/virologia , Perus/virologia
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