Immunoinformatics analysis and antibody epitope comparison of Newcastle disease virus classical vaccines with a virus involved in the fifth NDV panzootic

Abstract

Newcastle disease virus (NDV) has negatively affected the poultry industry worldwide. Given that the antigenic similarity of a vaccine strain to a field virus is effective in protection, an immunoinformatics study was performed to examine the similarity between antibody epitopes of classical vaccines and a sub-genotype VII.2 NDV (VII.2 NDV). Considering the role of fusion (F) and hemagglutinin-neuraminidase (HN) proteins in the induction of neutralizing antibodies, the 3D structure of HN and F proteins of the VII.2 NDV and nine vaccine strains were predicted, refined, and validated. Using these structures, linear and conformational antibody epitopes were mapped. Epitope analysis showed distinct results from the evolutionary distance and protein identity analysis and it was found that the range of difference in the number of identical epitopes in relation to F is wider than HN protein. LaSota and B1 vaccine strains showed the least epitope identity to the VII.2 NDV. The V4 and I-2 vaccine strains showed the highest epitope identity with the VII.2 NDV especially in F protein which is important in virus cell-to-cell transmission. In conclusion, excellence of the LaSota vaccine under field condition shows that protection is not just about epitope similarities and especially in the case of live vaccines, the vaccine-induced damage, replicative capacity and tropism of the vaccine strain are important. The prediction of this study may be useful for inactivated vaccines in which the amount of antigen is all that matters.

Superior Efficacy of Apathogenic Genotype I (V4) over Lentogenic Genotype II (LaSota) Live Vaccines against Newcastle Disease Virus Genotype VII.1.1 in Pathogen-Associated Molecular Pattern-H9N2 Vaccinated Broiler Chickens

“…Further, Kim et al [12] reported that the F protein plays the most important role in the protection of virus infection following the use of genotype-matched vaccines. Tabatabaeizadeh [65] recorded that, the number of identical linear and conformational neutralizing epitopes of F and HN proteins (n = 15) of the vaccine strains compared with the VII.2 NDV were as follows: (V4 = 14) > (I-2 = 11) > (Ulster, VG/GA, and R2B = 10) > (F = 9) > (LaSota = 7) > (PHY.LMV.42 = 6) > (B1 = 5). In the same previous study, V4 and I-2 vaccine strains showed the highest number of identical epitopes compared with the other vaccine strains, while the B1, PHY.LMV.42, and LaSota strains revealed the lowest epitope identity compared with VII.2 NDV, "especially in F protein".…”