Escherichia coli expression of NDV fusion protein gene and determination of its antigenic epitopes

Abstract

Recurrent outbreaks of Newcastle disease have questioned the usage of existing vaccines that whether they are still adequate to protect clinical diseases and inhibit virus transmission in poultry. Advancement in molecular biology has led to the production of recombinant vaccines in recent years, which can be a more useful strategy to control infections of Newcastle disease virus (NDV). Studies indicate that the pathogenic nature of NDV is mediated by its membrane associated fusion (F) protein. Here we report the cloning of the full-length F gene-pET30a and its expression in Escherichia coli BL21 DE3 cells through isopropyl β-D-1-thiogalactopyranoside induction. Transferring the protein on nitrocellulose membrane in Western blotting confirmed its specificity with histidine-tagged antibody reaction at the proper size of 67 kDa. Protein purification with nickel charged sepharose column affinity chromatography resulted in a single band of 67 kDa purified His-tag F protein on SDS-PAGE. Analysis of its immunogenicity through bioinformatics tools revealed that more than 70% of its sequence is antigenically active comprising 24 linear immunogenic peptides predicted by the Linear epitope prediction tool and 9 immunogenic peptides predicted by ElliPro. This is a key achievement of the study, which may lead towards recombinant vaccine production in future. In conclusion, our findings suggest that rather than employing live viral vaccines, using a purified immunogenic recombinant F protein as a vaccine or cloning the same gene in a suitable plant vector for production of edible vaccine will provide better protection against the NDV into chicken.

Immunogenicity of the Multi-Epitopic Recombinant Glycoproteins of Newcastle Disease Virus: Implications for the Serodiagnosis Applications

“…A comparison of the endpoint titers showed that there are not statistically significant differences. These results were in line with the findings of other researchers using similar epitopic or the full-length of F or HN protein for immunogenicity in the animal models (16, 17, 19). Furthermore, the detection of the HN and F glycoproteins with the individually produced antibodies revealed the potential application of these antibodies as probes for the viral glycoprotein in immunological analyses.…”

“…However, there is relatively limited information about the immunological properties of the recombinant surface glycoproteins of the NDV expressed in the E. coli system. There are a few reports about the successful expression and purification of NDV glycoproteins in the E. coli in which the recombinant HN was used as main the component in the ELISA based method (17) and purification of the immunogenic F protein that were studied elsewhere (18, 19).…”

E. coli expression and immunological assessment of expressed recombinant Newcastle disease virus hemagglutinin-neuraminidase protein in chickens

“…the hN protein is the most important antigen that can induce a strong immune response. the hN protein is a capsid protein that attaches itself firmly to the viral membrane, thus making it very difficult to isolate and purify from infected cells (Shahid et al, 2015). immunization with recombinant hN protein has been attempted many times to study protective immune responses in chickens (Boursnell et al, 1990;Edbauer et al, 1990;Sun et al, 2008;Su et al, 2011).…”