No abstract available.
Animals ; Baculoviridae* ; Newcastle disease virus* ; Newcastle Disease*

Recent advances in reverse genetics techniques make it possible to manipulate the genome of RNA viruses such as Newcastle disease virus (NDV). Several NDV vaccine strains have been used as vaccine vectors in poultry, mammals, and humans to express antigens of different pathogens. The safety, immunogenicity, and protective efficacy of these NDV-vectored vaccines have been evaluated in pre-clinical and clinical studies. The vaccines are safe in mammals, humans, and poultry. Bivalent NDV-vectored vaccines against pathogens of economic importance to the poultry industry have been developed. These bivalent vaccines confer solid protective immunity against NDV and other foreign antigens. In most cases, NDV-vectored vaccines induce strong local and systemic immune responses against the target foreign antigen. This review summarizes the development of NDV-vectored vaccines and their potential use as a base for designing other effective vaccines for veterinary and human use.
Animals ; Genome ; Humans ; Mammals ; Newcastle disease virus* ; Newcastle Disease* ; Poultry ; Reverse Genetics ; RNA Viruses ; Vaccines*

A Newcastle disease virus (NDV) isolate designated IBS002 was isolated from a commercial broiler farm in Malaysia. The virus was characterised as a virulent strain based on the multiple basic amino acid motif of the fusion (F) cleavage site 112RRRKGF117 and length of the C-terminus extension of the hemagglutinin-neuraminidase (HN) gene. Furthermore, IBS002 was classified as a velogenic NDV with mean death time (MDT) of 51.2 h and intracerebral pathogenicity index (ICPI) of 1.76. A genetic distance analysis based on the full-length F and HN genes showed that both velogenic viruses used in this study, genotype VII NDV isolate IBS002 and genotype VIII NDV isolate AF2240-I, had high genetic variations with genotype II LaSota vaccine. In this study, the protection efficacy of the recombinant genotype VII NDV inactivated vaccine was also evaluated when added to an existing commercial vaccination program against challenge with velogenic NDV IBS002 and NDV AF2240-I in commercial broilers. The results indicated that both LaSota and recombinant genotype VII vaccines offered full protection against challenge with AF2240-I. However, the LaSota vaccine only conferred partial protection against IBS002. In addition, significantly reduced viral shedding was observed in the recombinant genotype VII-vaccinated chickens compared to LaSota-vaccinated chickens.
Amino Acids, Basic ; Animals ; Chickens* ; Genetic Variation ; Genotype* ; Malaysia ; Newcastle disease virus* ; Newcastle Disease* ; Vaccination ; Vaccines* ; Virulence ; Virus Shedding

The aim of this study was to develop a semi-quantitative immunochromatographic method for rapid detection of Newcastle disease virus (NDV) antibodies by expressing HN protein in rice endosperm bioreactor. The recombinant plasmid pUC57-HN was digested by MlyⅠ and XhoⅠ to retrieve the HN gene, while the intermediate vector pMP3 containing promoter, signal peptide and terminator was digested by NaeⅠ and XhoⅠ. The HN gene and the linearized pMP3 were purified and ligated to form a recombinant plasmid pMP3-HN1. Subsequently, pMP3-HN1 and plant vector pCAMBIA1300 were digested by EcoRⅠ and Hind Ⅲ, and the HN1 gene was cloned into pCAMBIA1300. The recombinant plasmid pCAMBIA1300-HN1 was introduced into Agrobacterium tumefaciens EHA105 by electrotransformation, and the pCAMBIA1300-HN1 was transferred into rice callus by agrobacterium-mediated method. After dark culture, callus screening, differentiation, rooting and transplanting, transgenic rice seeds were obtained 4 months later. PCR identified that the HN gene has been inserted into the rice genome. SDS-PAGE and Western blotting indicated that the HN protein was successfully expressed in the positive rice endosperm. The purity of the HN protein was more than 90% by SP cation exchange chromatography and gel filtration chromatography. According to the national standards for the diagnostic techniques of Newcastle disease HI test (HI≥4log₂, positive antibody reaction), a colloidal gold labeled purified HN protein was used to prepare a semi-quantitative test strip by double-antibody sandwich method for rapid detection of NDV antibody. The results showed that the test strip did not cross-react with positive sera against other viruses, and the sensitivity of the test strip reached 1:102 400 for standard positive sera of Newcastle disease. Testing of a total of 308 clinical sera showed that the compliance rate of the test strip with HI test was 97.08%, and the Kappa value was 0.942. In conclusion, high purity recombinant HN protein was obtained from rice endosperm, and a simple, rapid, highly sensitive and highly specific semi-quantitative immunochromatographic strip was developed. The test strip could be used for immune evaluation of the Newcastle disease vaccine.
Animals ; Antibodies, Viral ; Chickens ; HN Protein/metabolism* ; Newcastle Disease/prevention & control* ; Newcastle disease virus/metabolism* ; Oryza/genetics*

To expand the epidemiological understanding of Newcastle disease in Jeju Province, Korea, active surveillance was extensively performed through a virological examination for poultry farms and wild birds in Jeju Province during 2007~2008. Samples (swabs or fresh feces) were collected from a total of 6,485 birds including 6,405 domestic birds (chickens, ducks, pheasants, geese, quails, turkeys, and ostriches) and 80 wild birds. A total of 24 hemagglutinating agents were isolated from domestic birds on fourteen farms including five Korean native chicken, one layer chicken, two broiler chicken, four duck and two pheasant farms. The hemagglutinating agents were all identified as lentogenic NDV based on the reverse transcriptase polymerase chain reaction, sequence analysis of amino acids on the F cleavage site and mean death time in chicken embryos. The F gene-based phylogenetic analysis revealed that the NDV isolates were classified into genotypes 1 or 2 of class II. These lentogenic viruses were closely related to NDV vaccine strains used in Jeju Province. Active surveillance conducted for Newcastle disease indicates no scientific evidence of virulent NDV infection in chickens in Jeju Province, Korea since 2005.
Amino Acids ; Animals ; Birds ; Chickens ; Ducks ; Embryonic Structures ; Geese ; Genotype ; Korea ; Newcastle Disease ; Newcastle disease virus ; Poultry ; Quail ; Reverse Transcriptase Polymerase Chain Reaction ; Sequence Analysis ; Turkeys

A neutralization-resistant mutant of Newcastle disease virus (NDV) Kr005 strain belonging to class II genotype VII was generated using a neutralizing monoclonal antibody and its biological effects were assessed. The mutant showed single amino acid substitution (E to K) at position 347 of the hemagglutinin-neuraminidase (HN) protein (E347K mutant). The E347K mutant exhibited marked rounding of the cells and few syncytia in infected chicken embryofibroblast (CEF) cells. The hemadsorption and neuraminidase activities of the E347K mutant of the wild-type virus were 118% and 166%, respectively. The mutant produced a rapid elution pattern whereas the wild type had a slow elution pattern. Growth kinetics studies showed that the E347K mutant produced an 80-times higher yield of extracellular virus in CEF cells compared with the wild-type virus. The time-course virus titer showed a marked increase in mutant-infected cells from 6 h to 12 h post infection (pi), which was consistent with the titer pattern time-course for NA activity. The E347K mutant virus showed a slight decrease in virulence compared to the wild-type virus, but there was no change in pathotype when measured by in vivo pathogenicity testing. These results suggest that an E347K mutation in HN protein might be associated with increased NA activity and subsequent enhancement of virus release from infected cells without change in viral pathotype.
Amino Acid Substitution ; Animals ; Chickens ; Genotype ; Giant Cells ; Hemadsorption ; HN Protein ; Kinetics ; Neuraminidase ; Newcastle Disease ; Newcastle disease virus ; Sprains and Strains ; Viral Load ; Virus Release ; Viruses

Raw white rice has not been considered a good carrierfor oral vaccination, probably because of its antiviralactivity. Methods are required to overcome antiviralactivity in raw white rice. This study was carried out todetermine the effects of various treatments of raw whiterice on the survival of strain I-2 of Newcastle diseasevirus. These included cooking and baking the rice ormixing the rice with vegetable oil prior to coating withvaccine virus. The vaccine-coated rice was then stored for30min and 24h, followed by quantitative recovery of thevirus. Thirty min after mixing, uncooked, cooked, andbaked rice, and rice mixed with vegetable oil showed titersof 10(6.2), 10(7.2), 10(6.6), and 10(7.0) EID50/0.1ml, respectively.After storage for 24h at 22-25oC, the titers dropped to10(5.0), 10(6.5), 10(5.0), and 10(6.0) EID50/0.1ml for uncooked,cooked, baked, and oiled rice, respectively.
Animals ; Chick Embryo ; Chickens ; Cookery ; Newcastle Disease/*virology ; Newcastle disease virus/growth & development/*physiology ; Oryza sativa/chemistry/*virology ; Viral Vaccines/chemistry

Rabies remains an important worldwide health problem. Newcastle disease virus (NDV) was developed as a vaccine vector in animals by using a reverse genetics approach. Previously, our group generated a recombinant NDV (LaSota strain) expressing the complete rabies virus G protein (RVG), named rL-RVG. In this study, we constructed the variant rL-RVGTM, which expresses a chimeric rabies virus G protein (RVGTM) containing the ectodomain of RVG and the transmembrane domain (TM) and a cytoplasmic tail (CT) from the NDV fusion glycoprotein to study the function of RVG's TM and CT. The RVGTM did not detectably incorporate into NDV virions, though it was abundantly expressed at the surface of infected BHK-21 cells. Both rL-RVG and rL-RVGTM induced similar levels of NDV virus-neutralizing antibody (VNA) after initial and secondary vaccination in mice, whereas rabies VNA induction by rL-RVGTM was markedly lower than that induced by rL-RVG. Though rL-RVG could spread from cell to cell like that in rabies virus, rL-RVGTM lost this ability and spread in a manner similar to the parental NDV. Our data suggest that the TM and CT of RVG are essential for its incorporation into NDV virions and for spreading of the recombinant virus from the initially infected cells to surrounding cells.
Animals ; Antibody Formation ; Cytoplasm* ; Glycoproteins* ; GTP-Binding Proteins ; Humans ; Mice ; Newcastle disease virus* ; Newcastle Disease* ; Parents ; Rabies virus ; Rabies* ; Reverse Genetics ; Tail* ; Vaccination ; Virion*

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

PURPOSE: The aim of the present study was to develop a serodiagnostic test for differentiation infected from vaccinated animal (DIVA) strategy accompanying the marker vaccine lacking an immunodominant epitope (IDE) of nucleoprotein of Newcastle disease virus (NDV). MATERIALS AND METHODS: Recombinant epitope-repeat protein (rERP) gene encoding eight repeats of the IDE sequence (ETQFLDLMRAVANSMR) by tetra-glycine linker was synthesized. Recombinant baculovirus carrying the rERP gene was generated to express the rERP in insect cells. Specificity and sensitivity of an indirect enzyme-linked immunosorbent assay (ELISA) employing the rERP was evaluated. RESULTS: The rERP with molecular weight of 20 kDa was successfully expressed by the recombinant baculovirus in an insect-baculovirus system. The rERP was antigenically functional as demonstrated by Western blotting. An indirect ELISA employing the rERP was developed and its specificity and sensitivity was determined. The ELISA test allowed discrimination of NDV infected sera from epitope deletion virus vaccinated sera. CONCLUSION: The preliminary results represent rERP ELISA as a promising DIVA diagnostic tool.
Animals ; Baculoviridae ; Blotting, Western ; Discrimination (Psychology) ; Enzyme-Linked Immunosorbent Assay ; Insects ; Molecular Weight ; Newcastle disease virus* ; Newcastle Disease* ; Nucleoproteins ; Sensitivity and Specificity