Small interfering ribonucleic acid (siRNA)-induced RNA degradation can inhibit viral infection, and has been investigated extensively for its efficacy as antiviral therapy. The potential therapeutic role of lentiviral-mediated short hairpin ribonucleic acid (shRNA) to Newcastle disease virus (NDV) replication in vivo has been explored less often. We constructed two recombinant lentiviral vectors containing shRNA against the phosphoprotein (P) of the NDV, RNAi-341 and RNAi-671. Recombinant shRNA lentivirus vectors were co-transfected into 293T cells, along with helper plasmids, to package the recombinant shRNA lentivirus. Lentivirus-based shRNAs were titrated and transduced into NDV-susceptible chicken embryo fibroblasts (CEFs) and chick embryos. Antiviral activity against the NDV strain was evaluated by virus titration and real-time reverse transcription-polymerase chain reaction. RNAi-341 and RNAi-671 strongly suppressed transient expression of a FLAG-tagged P fusion protein in 293T cells. RNAi-341 and RNAi-671 NDV reduced virus titers by 66.6-fold and 30.6-fold, respectively, in CEFs 16 h after infection. RNAi-341 and RNAi-671 reduced virus titers in specific pathogen-free chick embryos by 99% and 98%, respectively, 48 h after infection. Both shRNAs inhibited accumulation of not only P-gene mRNA, but also nucleocapsid, M-, F-, HN-, and L-gene mRNA. RNAi-341 silenced P-gene mRNA more potently than RNAi-671. These results suggest that shRNAs silencing the P gene had substantial antiviral properties and inhibited NDV replication in CEFs and chick embryos.
Animals ; Chick Embryo ; Chickens ; Down-Regulation ; Fibroblasts ; virology ; Gene Targeting ; Lentivirus ; genetics ; metabolism ; Newcastle Disease ; virology ; Newcastle disease virus ; genetics ; physiology ; Phosphoproteins ; genetics ; metabolism ; Poultry Diseases ; virology ; RNA Interference ; RNA, Small Interfering ; genetics ; metabolism ; Viral Proteins ; genetics ; metabolism ; Virus Replication

Characteristic clinical manifestations of Newcastle disease include leukopenia and immunosuppression. Peripheral blood mononuclear cells (PBMCs) are the main targets of Newcastle disease virus (NDV) infection. To survey changes in proteomic expression in chicken PBMCs following NDV infection, PBMC proteins from 30 chickens were separated using two-dimensional electrophoresis (2-DE) and subjected to mass spectrometry analysis. Quantitative intensity analysis showed that the expression of 78 proteins increased more than two-fold. Thirty-five proteins exhibited consistent changes in expression and 13 were identified as unique proteins by matrix assisted laser desorption ionization-time of flight mass spectrometer/mass spectrometer including three that were down-regulated and 10 that were up-regulated. These proteins were sorted into five groups based on function: macromolecular biosynthesis, cytoskeleton organization, metabolism, stress responses, and signal transduction. Furthermore, Western blot analysis confirmed the down-regulation of integrin-linked kinase expression and up-regulation of lamin A production. These data provide insight into the in vivo response of target cells to NDV infection at the molecular level. Additionally, results from this study have helped elucidate the molecular pathogenesis of NDV and may facilitate the development of new antiviral therapies as well as innovative diagnostic methods.
Animals ; Avian Proteins/*genetics/metabolism ; *Chickens ; *Gene Expression Regulation ; Leukocytes, Mononuclear/enzymology/virology ; Newcastle Disease/*genetics/virology ; Newcastle disease virus/*physiology ; Poultry Diseases/*genetics/virology ; *Proteome ; Specific Pathogen-Free Organisms ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/veterinary ; Tandem Mass Spectrometry/veterinary

A recombinant hemagglutinin-neuraminidase (rHN) protein from Newcastle disease virus (NDV) with hemagglutination (HA) activity was expressed in Spodoptera frugiperda cells using a baculovirus expression system. The rHN protein extracted from infected cells was used as an antigen in a hemagglutination inhibition (HI) test for the detection and titration of NDV-specific antibodies present in chicken sera. The rHN antigen produced high HA titers of 2(13) per 25 microL, which were similar to those of the NDV antigen produced using chicken eggs, and it remained stable without significant loss of the HA activity for at least 12 weeks at 4degrees C. The rHN-based HI assay specifically detected NDV antibodies, but not the sera of other avian pathogens, with a specificity and sensitivity of 100% and 98.0%, respectively, in known positive and negative chicken sera (n = 430). Compared with an NDV-based HI assay, the rHN-based HI assay had a relative sensitivity and specificity of 96.1% and 95.5%, respectively, when applied to field chicken sera. The HI titers of the rHN-based HI assay were highly correlated with those in an NDV-based HI assay (r = 0.927). Overall, these results indicate that rHN protein provides a useful alternative to NDV antigen in HI assays.
Animals ; Antibodies, Viral/*blood ; Antigens, Viral/*diagnostic use/genetics/metabolism ; Baculoviridae/genetics ; Chickens ; HN Protein/*diagnostic use/genetics/metabolism ; Hemagglutination Inhibition Tests/*methods/veterinary ; Newcastle Disease/*diagnosis/immunology/virology ; Newcastle disease virus/genetics/*immunology/metabolism ; Poultry Diseases/*diagnosis/immunology/virology ; Recombinant Proteins/diagnostic use/genetics/metabolism ; Sf9 Cells ; Spodoptera

Three Newcastle disease virus (NDV) strains recovered from ND outbreaks in chickens and duck flocks in north china during 2009 to 2011 were completely sequenced and biologically characterized. All the strains were velogenic and had the velogenic motif 112R-R-Q-K-R-F117 which was consistent with the results of biological tests. Analysis of the variable region (nucleotide 47 to 420) of the F gene indicated that the three isolates belonged to genotype VII d. Cross hemagglutination inhibition test indicated that the antigen homology between three isolates and LaSota were 82.5%-89.4%, the homology between the two isolates from chicken was 90%. A cross-protection experiment in which specific-pathogen-free chickens vaccinated with LaSota were challenged by SDLY01 isolate showed that LaSota vaccine could provide complete protection against SDLY01, however virus discharge could be detected on fifth day. Challenge experiment in which Cherry Valley duck of 30 day old challenged with SD03 strain indicated that cherry valley duck had no disease in experiment period, but virus discharge could be detected from Larynx and cloaca until fifth day. Genome length of three NDV isolates was 15192bp and belonged to genotype VII d. Sequence analysis clarified that the whole genomic sequence of these three isolates shared high homology with NDV virus strains isolated from goose and duck over the same period, which elucidated that NDV isolated from goose, duck or chicken had close genetics and epidemiological relationship.
Amino Acid Sequence ; Animals ; Bird Diseases ; virology ; Chickens ; Columbidae ; Ducks ; Geese ; Genome, Viral ; Molecular Sequence Data ; Newcastle Disease ; virology ; Newcastle disease virus ; chemistry ; classification ; genetics ; isolation & purification ; Phylogeny ; Sequence Alignment ; Viral Proteins ; chemistry ; genetics

Based on the complete genome sequence of pigeon-origin Newcastle disease virus strain JS/07/04/ Pi(genotype VIb), nine overlapped fragments covering its full-length genome were amplified by RT-PCR. The fragments were connected sequentially and then inserted into the transcription vector TVT7/R resulting in the TVT/071204 which contained the full genome of strain JS/07/04/Pi. The TVT/071204 was co-transfected with three helper plasmids pCI-NP, pCI-P and pCI-L into the BSR cells, and the transfected cells and culture supernatant were inoculated into 9-day-old SPF embryonated eggs 60 h post-transfection. The HA and HI tests were conducted following the death of embryonated eggs. The results showed that the allantoic fluids obtained were HA positive and the HA could be inhibited by anti-NDV serum which indicated that the strain JS/07/04/Pi was rescued successfully. The rescued virus rNDV/071204 showed similar growth kinetics to its parental virus in CEF. The successful recovery of this strain would contribute to the understanding of the host-specificity of pigeon-origin NDV and to the development of the novel vaccines against the NDV infection in pigeons.
Animals ; Base Sequence ; CHO Cells ; Chick Embryo ; Columbidae ; virology ; Cricetinae ; Cricetulus ; DNA, Complementary ; genetics ; Fluorescent Antibody Technique, Indirect ; Molecular Sequence Data ; Newcastle disease virus ; genetics ; growth & development

Based on the genomic sequence of NDV08-004 strain (GenBank accession number FJ794269), seven pairs of primers were designed to amplify the genomic fragments by RT-PCR and cloned into pGEM-Teasy vector. The fragments (named A to G) were sub-cloned into transcription vector pOLTV5 according to the universal RE site and the plasmid named NDV08-004-pO which contained the full length cDNA of NDV08-004 strain was constructed. Three helper plasmids (pCI-NP, pCI-P and pCI-L) together with NDV08-004-pO were co-transfected into BSR T7/5 cells, and the transfection supernatant was inoculated into SPF embryonated eggs to rescue the virus. The virus was rescued successfully and identified by HA and RT-PCR and sequencing. The rescue system constructed in this study provided a good foundation for the further related research.
Animals ; Base Sequence ; Chick Embryo ; Genetic Vectors ; genetics ; Molecular Sequence Data ; Newcastle Disease ; virology ; Newcastle disease virus ; genetics ; Plasmids ; Reverse Genetics ; methods

In chicken fibroblast cell (CEF) cultures with antiserum against Newcastle disease virus (NDV) strain TZ060107, the virus was passed serially for 50 passages in 3 independent lineages. HN and F genes were amplified and sequenced every 10 passages. The derived virus A1-50 with most mutations among 3 lineages was further passed for another 50 passages in CEF with or without antiserum against A1-50, each in 3 independent lineages. Sequence comparisons for HN and F genes of 60, 70, 80, 90 and 100 passages indicated that the ratio of nonsynonymous mutations (NS) vs synonymous mutations (S) for HN genes in the lineages passed with antiserum against A1-50 was 5.25, which was obviously higher than 2. 375 of NS/ S in the lineages without the antiserum. The stable NS mutations occurred in the first 50 passages with the antiserum against the original TZ060107 were still maintained and one more new stable NS mutation appeared. For the F gene, 3 new stable NS mutations occurred during the second 50 passages in lineages with antiserum against A1-50 when the original NS mutations obtained in the first 50 passages with antiserum against TZ060107 still existed. Cross hemagglutination inhibition (HI) between original virus and its derivative viruses indicated that the more continuous passages in cell culture with antiserum passed, the bigger difference of antigenicity between the virus and the original virus had.
Amino Acid Sequence ; Animals ; Antibodies, Viral ; immunology ; Base Sequence ; Chickens ; Evolution, Molecular ; HN Protein ; genetics ; immunology ; Hemagglutination Inhibition Tests ; Molecular Sequence Data ; Mutation ; Newcastle Disease ; immunology ; virology ; Newcastle disease virus ; genetics ; immunology ; Poultry Diseases ; Viral Fusion Proteins ; genetics ; immunology

Newcastle disease (ND) caused by virulent Newcastle disease virus (NDV) is a highly contagious viral disease of poultry. Virulent NDVs characteristically have a multibasic amino acid sequence (virulence motif) such as (112)RRQKRF(117) at the cleavage site of the precusor fusion (F0) protein. The antigenic and immunogenic characteristics of the virulence motif (112)RRQKRF(117) in the F0 protein of virulent NDVs were investigated. Epitope mapping analysis revealed that a RRQKRF-specific monoclonal antibody 4G2 recognized the KRF section of the motif. A synthetic peptide bearing the RRQKRF motif reacted strongly with sera from virulent NDV (with RRQKRF motif)-infected chickens. These sera also showed reactivity to peptides bearing other virulence motifs ((112)KRQKRF(117), (112)RRQRRF(117) and (112)RRRKRF(117)) but not an avirulence motif ((112)GRQGRL(117)) by ELISA. The synthetic bearing RRQKRF motif reacted with 60% to 91% of sera taken from surviving chickens on ND outbreak farms but not with sera from vaccinated birds, even though most of the sera had antibody to NDV due to vaccination. This indicates that the virulence motif has the potential to differentiate virulent NDV infected birds from vaccinated birds.
Amino Acid Motifs/*immunology ; Amino Acid Sequence ; Animals ; Chickens ; Enzyme-Linked Immunosorbent Assay/veterinary ; Epitope Mapping/veterinary ; Newcastle Disease/*immunology ; Newcastle disease virus/*genetics/pathogenicity ; Poultry Diseases/*immunology/*virology ; Serologic Tests/veterinary ; Viral Fusion Proteins/*genetics/immunology ; Virulence/genetics

Twenty Newcastle disease virus (NDV) strains were isolated from chickens and geese in the field outbreaks during 2005 and 2006 in some regions of Jiangsu and Guangxi province. Assessment of the virulence by MDT and ICPI, RT-PCR and sequence analysis of fusion protein gene were used to compare the properties of NDV isolates. The results indicated that MDT and ICPI of the isolates were 45.3h - 58.2h and 1.61 - 2.00 respectively, which confirmed that the all NDV isolates were highly virulent. And their hemagglutinin were not resistant to heat and belonged to fast pattern of elution. The results of nucleotide sequencing and phylogentic analysis of fusion protein gene showed that the twenty strains shared homology from 79.7% to 100% among themselves, from 78.1% to 83.4% and from 80.2% to 90.1% with NDV LaSota, F48E8, respectively. The putative amino acid sequences of fusion protein at the cleavage sites of all the isolates were 112R-R-Q-R/K-R-F117, with the motif characteristics of the virulent NDV strain, which was in accordant with the results of assessment of the pathogenicity. The phylogentic tree based on sequences of fusion protein gene variable regions (47-420nt) revealed that the 18 strains belonged to sub-genotype VIId and the others belonged to an old genotype III of NDV, revealing that subgenotype VIId virus was responsible for the NDV outbreaks in some regions of Jiangsu and Guangxi promince recently.
Amino Acid Motifs ; Amino Acid Sequence ; Animals ; Base Sequence ; Chickens ; virology ; China ; epidemiology ; Disease Outbreaks ; Geese ; virology ; Molecular Epidemiology ; Newcastle Disease ; epidemiology ; genetics ; Newcastle disease virus ; genetics ; pathogenicity ; Phylogeny ; Poultry Diseases ; epidemiology ; genetics ; virology ; Reverse Transcriptase Polymerase Chain Reaction ; Viral Fusion Proteins ; genetics

An outbreak of fever and dyspnea with high incidence rate and case fatality rate occurred among pigs in a pigfarm in Jilin province, China, in 2000. The paramyxovirus-like particles could be observed in lungs, spleens and kidneys of the dead pigs under the transmission electron microscope. A Newcastle disease virus (NDV) isolate designated as JL01 was determined as the causal agent for the disease outbreak. The purified virus was reinoculated into pigs, and then the pigs infected with the virus showed similar symptoms, and the HI antibody of NDV could be detected from the reinoculated pigs. The MDT, ICPI and EID50 of the JL01 isolate was 55.2h, 1.60 and 10(-7.5)/0.1 mL respectively. The F gene of JL01 was cloned and sequenced, and the results showed that the identities of F gene shared by JL01 and avirulent NDV reference strains were from 91.5% to 98.5%, and could be ascribed to NDV genotype I. Thus, the swine NDV JL01 strain should be an avirulent strain with gene variation, but the virulence of JL01 was just the same as velogenic strains.
Animals ; Chickens ; Dogs ; Horses ; Mice ; Microscopy, Electron ; Newcastle Disease ; virology ; Newcastle disease virus ; classification ; genetics ; isolation & purification ; ultrastructure ; Phylogeny ; Polymerase Chain Reaction ; Rabbits ; Sequence Analysis, DNA ; Swine ; Swine Diseases ; virology ; Viral Proteins ; genetics