Antibody response to Newcastle disease virus recombinant fusion protein in post-vaccinated laying hens

This study was aimed to analyze the antibody response in laying hens post-vaccination to Newcastle disease virus (NDV) recombinant fusion (F) protein, which has been successfully expressed using the F gene of local isolates from Kulon Progo Strain (0663/04/2013), Yogyakarta, Indonesia. The F gene was cloned into an expression vector plasmid pBT7-N-His. Two types of NDV vaccine, a concentrated and pure F recombinant protein, were used for vaccination. The concentrated recombinant F protein was collected from centrifugal ultrafiltration, while the pure sample was obtained from the electroelution process. Recombinant F protein of NDV was successfully expressed, purified, and
visualized by Sodium Dodecyl Sulphate–Polyacrylamide Gel Electrophoresis (SDS-PAGE) and Coomassie Brilliant Blue staining with a molecular weight of 28 kDa. The two types of recombinant F protein and a commercial live vaccine as a positive control were injected two times at 14 and 18th
weeks of age in laying hens to analyze the antibody response in serum. In comparison with a commercial live NDV vaccine, indirect Enzyme-linked Immunosorbent Assay (ELISA) revealed that antibody responses were high in both recombinant F protein vaccinated groups. Therefore, the recombinant F protein has the potential to be developed as a vaccine candidate to obtain a higher antibody response in laying hens compared to commercially available live NDV vaccines.