Correction: Generation by Reverse Genetics of an Effective, Stable, Live-Attenuated Newcastle Disease Virus Vaccine Based on a Currently Circulating, Highly Virulent Indonesian Strain.

[This corrects the article DOI: 10.1371/journal.pone.

Contributions of HA1 and HA2 Subunits of Highly Pathogenic Avian Influenza Virus in Induction of Neutralizing Antibodies and Protection in Chickens.

Highly pathogenic avian influenza virus (HPAIV) subtype H5N1 causes a devastating disease in poultry. Vaccination is an effective method of controlling avian influenza virus (AIV) infection in poultry. The hemagglutinin (HA) protein is the major determinant recognized by the immune system of the host.

Author Correction: A recombinant avian paramyxovirus serotype 3 expressing the hemagglutinin protein protects chickens against H5N1 highly pathogenic avian influenza virus challenge.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

A recombinant avian paramyxovirus serotype 3 expressing the hemagglutinin protein protects chickens against H5N1 highly pathogenic avian influenza virus challenge.

Highly pathogenic avian influenza (HPAI) is a devastating disease of poultry and a serious threat to public health. Vaccination with inactivated virus vaccines has been applied for several years as one of the major policies to control highly pathogenic avian influenza virus (HPAIV) infections in chickens. Viral-vectored HA protein vaccines are a desirable alternative for inactivated vaccines.

Author Correction: A Recombinant Newcastle Disease Virus (NDV) Expressing S Protein of Infectious Bronchitis Virus (IBV) Protects Chickens against IBV and NDV.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Novel avian paramyxovirus-based vaccine vectors expressing the Ebola virus glycoprotein elicit mucosal and humoral immune responses in guinea pigs.

Paramyxovirus vaccine vectors based on human parainfluenza virus type 3 (HPIV-3) and Newcastle disease virus (NDV) have been previously evaluated against Ebola virus (EBOV) challenge. Although both the viral vectored vaccines efficiently induce protective immunity, some concerns remain to be solved. Since HPIV-3 is a common human pathogen, the human population has pre-existing immunity to HPIV-3, which may restrict the replication of the vaccine vector.

Development of a recombinant Newcastle disease virus-vectored vaccine for infectious bronchitis virus variant strains circulating in Egypt.

Infectious bronchitis virus (IBV) causes a major disease problem for the poultry industry worldwide. The currently used live-attenuated vaccines have the tendency to mutate and/or recombine with circulating field strains resulting in the emergence of vaccine-derived variant viruses. In order to circumvent these issues, and to develop a vaccine that is more relevant to Egypt and its neighboring countries, a recombinant avirulent Newcastle disease virus (rNDV) strain LaSota was constructed to express the codon-optimized S glycoprotein of the Egyptian IBV variant strain IBV/Ck/EG/CU/4/2014 belonging to GI-23 lineage, that is prevalent in Egypt and in the Middle East.

A Recombinant Newcastle Disease Virus (NDV) Expressing S Protein of Infectious Bronchitis Virus (IBV) Protects Chickens against IBV and NDV.

Infectious bronchitis virus (IBV) causes a highly contagious respiratory, reproductive and urogenital tract disease in chickens worldwide, resulting in substantial economic losses for the poultry industry. Currently, live-attenuated IBV vaccines are used to control the disease. However, safety, attenuation and immunization outcomes of current vaccines are not guaranteed.

Effect of fusion protein cleavage site sequence on generation of a genotype VII Newcastle disease virus vaccine.

Newcastle disease (ND) causes severe economic loss to poultry industry worldwide. Frequent outbreaks of ND in commercial chickens vaccinated with live vaccines suggest a need to develop improved vaccines that are genetically matched against circulating Newcastle disease virus (NDV) strains. In this study, the fusion protein cleavage site (FPCS) sequence of NDV strain Banjarmasin/010 (Banj), a genotype VII NDV, was individually modified using primer mutagenesis to those of avian paramyxovirus (APMV) serotypes 2, 7 and 8 and compared with the recombinant Banjarmasin (rBanj) with avirulent NDV LaSota cleavage site (rBanj-LaSota).

Complete genome sequences of two avian infectious bronchitis viruses isolated in Egypt: Evidence for genetic drift and genetic recombination in the circulating viruses.

Avian infectious bronchitis virus (IBV) is highly prevalent in chicken populations and is responsible for severe economic losses to poultry industry worldwide. In this study, we report the complete genome sequences of two IBV field strains, CU/1/2014 and CU/4/2014, isolated from vaccinated chickens in Egypt in 2014. The genome lengths of the strains CU/1/2014 and CU/4/2014 were 27,615 and 27,637 nucleotides, respectively.

Evaluation of fusion protein cleavage site sequences of Newcastle disease virus in genotype matched vaccines.

Newcastle disease virus (NDV) causes a devastating poultry disease worldwide. Frequent outbreaks of NDV in chickens vaccinated with conventional live vaccines suggest a need to develop new vaccines that are genetically matched against circulating NDV strains, such as the genotype V virulent strains currently circulating in Mexico and Central America. In this study, a reverse genetics system was developed for the virulent NDV strain Mexico/01/10 strain and used to generate highly attenuated vaccine candidates by individually modifying the cleavage site sequence of fusion (F) protein.

A novel chimeric Newcastle disease virus vectored vaccine against highly pathogenic avian influenza virus.

Avian influenza (AI) is an economically-important disease of poultry worldwide. The use of vaccines to control AI has increased because of frequent outbreaks of the disease in endemic countries. Newcastle disease virus (NDV) vectored vaccine has shown to be effective in protecting chickens against a highly pathogenic avian influenza virus (HPAIV) infection.

A Y527A mutation in the fusion protein of Newcastle disease virus strain LaSota leads to a hyperfusogenic virus with increased replication and immunogenicity.

Newcastle disease is a highly contagious and economically important disease of poultry. Low-virulence Newcastle disease virus (NDV) strains such as B1 and LaSota have been used as live vaccines, with a proven track record of safety and efficacy. However, these vaccines do not completely prevent infection or virus shedding.

Effects of naturally occurring six- and twelve-nucleotide inserts on Newcastle disease virus replication and pathogenesis.

Newcastle disease virus (NDV) isolates contain genomes of 15,186, 15,192 or 15,198 nucleotides (nt). The length differences reflect a 6-nt insert in the 5' (downstream) non-translated region (NTR) of the N gene (15,192-nt genome) or a 12-nt insert in the ORF encoding the P and V proteins (causing a 4-amino acid insert; 15,198-nt genome). We evaluated the role of these inserts in the N and P genes on viral replication and pathogenicity by inserting them into genomes of two NDV strains that have natural genome lengths of 15,186 nt and represent two different pathotypes, namely the mesogenic strain Beaudette C (BC) and the velogenic strain GB Texas (GBT).

Modified Newcastle disease virus vectors expressing the H5 hemagglutinin induce enhanced protection against highly pathogenic H5N1 avian influenza virus in chickens.

Naturally-occurring attenuated strains of Newcastle disease virus (NDV) are being developed as vaccine vectors for use in poultry and humans. However, some NDV strains, such as Beaudette C (BC), may retain too much virulence in poultry for safe use, and more highly attenuated strains may be suboptimally immunogenic. We therefore modified the BC strain by changing the multibasic cleavage site sequence of the F protein to the dibasic sequence of avirulent strain LaSota.

Evaluation of the contributions of individual viral genes to newcastle disease virus virulence and pathogenesis.

Unlabelled: Naturally occurring Newcastle disease virus (NDV) strains vary greatly in virulence. The presence of multibasic residues at the proteolytic cleavage site of the fusion (F) protein has been shown to be a primary determinant differentiating virulent versus avirulent strains. However, there is wide variation in virulence among virulent strains.

A recombinant Newcastle disease virus (NDV) expressing infectious laryngotracheitis virus (ILTV) surface glycoprotein D protects against highly virulent ILTV and NDV challenges in chickens.

Infectious laryngotracheitis (ILT) is a highly contagious acute respiratory disease of chickens caused by infectious laryngotracheitis virus (ILTV). Currently, modified live ILTV vaccines are used to control ILT infections. However, the live ILTV vaccines can revert to virulence after bird-to-bird passage and are capable of establishing latent infections, suggesting the need to develop safer vaccines against ILT.

Role of C596 in the C-terminal extension of the haemagglutinin-neuraminidase protein in replication and pathogenicity of a highly virulent Indonesian strain of Newcastle disease virus.

We modified the haemagglutinin-neuraminidase (HN) glycoprotein of the virulent Newcastle disease virus (NDV) strain Banjarmasin/010/10 (Ban/010) by adding C-terminal extensions similar to those found in certain avirulent NDV strains. Extension of the 571 aa wt Ban/010 HN protein to 577 and 616 aa by removal of one or two translational stop codons moderately reduced HN function and viral pathogenicity in 1-day-old and 3-week-old chickens. Substantially greater reductions were achieved by altering the 616 aa form by introducing a R596C mutation or by replacing the C-terminal extension with that of avirulent strain Ulster, which naturally contains the amino acid 596C.

Evaluation of the replication, pathogenicity, and immunogenicity of avian paramyxovirus (APMV) serotypes 2, 3, 4, 5, 7, and 9 in rhesus macaques.

Avian paramyxoviruses (APMV) serotypes 1-9 are frequently isolated from domestic and wild birds worldwide. APMV-1 (also called Newcastle disease virus, NDV) is attenuated in non-human primates and is being developed as a candidate human vaccine vector. The vector potential of the other serotypes was unknown.

Newcastle disease virus fusion protein is the major contributor to protective immunity of genotype-matched vaccine.

Virulent strains of Newcastle disease virus (NDV) can cause devastating disease in chickens worldwide. Although the current vaccines are substantially effective, they do not completely prevent infection, virus shedding and disease. To produce genotype-matched vaccines, a full-genome reverse genetics system has been used to generate a recombinant virus in which the F protein cleavage site has been changed to that of avirulent vaccine virus.

Mutations in the cytoplasmic domain of the Newcastle disease virus fusion protein confer hyperfusogenic phenotypes modulating viral replication and pathogenicity.

The Newcastle disease virus (NDV) fusion protein (F) mediates fusion of viral and host cell membranes and is a major determinant of NDV pathogenicity. In the present study, we demonstrate the effects of functional properties of F cytoplasmic tail (CT) amino acids on virus replication and pathogenesis. Out of a series of C-terminal deletions in the CT, we were able to rescue mutant viruses lacking two or four residues (rΔ2 and rΔ4).

Complete genome sequence of a highly virulent newcastle disease virus currently circulating in Mexico.

The complete genome sequence was determined for a highly virulent Newcastle disease virus strain from vaccinated chicken farms in Mexico during outbreaks in 2010. On the basis of phylogenetic analysis this strain was classified into genotype V in the class II cluster that was closely related to Mexican strains that appeared in 2004-2006.

Complete genome sequence of an avian paramyxovirus type 4 from north america reveals a shorter genome and new genotype.

An avian paramyxovirus type 4 (APMV-4) was isolated from a duck in Delaware in 2010. Its genome is 15,048 nucleotides (nt) long, which is shorter by 6 nt than those for all previously reported strains. Phylogenetic analysis revealed that this strain formed a separate cluster within APMV-4 strains.