Design and Evaluation of Multi-Epitope Based Vaccine against Newcastle Disease Virus

Abstract

Newcastle disease virus is a single stranded RNA virus of negative polarity, is the main causative agent of NDV infection in chickens. Despite the availability of commercial live attenuated vaccine, the outbreaks are common in poultry industry causing huge economic losses. The main factors responsible for the vaccine ineffectiveness are; high mutation rate, genetic variability of the virus and other factors causing immunosuppression in birds. In this study, computational and immune-informatics approach was used to design a multi- epitope vaccine based on the sequences reported from Pakistan. The 8 prioritized epitopes were predicted from structural proteins; HN and F of NDV. These non-host homologous epitopes were capable of inducing strong B cell, T cell and IFN- γ response against the virus. Furthermore, the epitopes were arranged on the basis of epitope - epitope interaction analysis and linked with each other through GPGPG linkers. An adjuvant (CTB) was added at the N terminal to enhance the immunogenicity of the construct. Construct was then modeled, refined and evaluated using online tools. Significant docking score signal out towards great interaction between vaccine construct and TLR receptors, thus enabling the vaccine to induce TLR activation which will be followed by an amplified immune response against the virus. These results show that the proposed vaccine construct can induce a strong innate and adaptive immune response against NDV in chickens, however, experimental validation will be necessary to confirm its potential. In future, this study can be utilized in finding genetic diversity among NDV strains reported globally from different regions of the world and can also be helpful in detection of genetic determinants associated vaccine resistance in vaccinated chickens.