Authors : FenYi He, JiongJie He, HuiLin Guo, Ming Yang, ZhiHua Chen and SiJiu Yu
Abstract: One pair of primers were designed based on F gene of Pigeon Paramyxovirus type I (PPMV-1) sequences reported in GenBank. F gene fragment about 1.66 kb was amplified by Reverse Transcription Polymerase Chain Reaction (RT-PCR) with the genome of Newcastle Disease Virus (NDV) PL strain as the template. Sequence analysis showed that F gene of PL strain shared 76.3-98.6% homology with the nucleotide sequence of F gene of domestic and foreign 17 strains PPMV-1 or NDV. The F gene of PL strain was inserted into eukaryotic expression vector PCDNA3.1V5HIS so eukaryotic expressing plasmid PCDNA3.1-PPMV-1-F was constructed. Researchers immunized some 1 month old young pigeons which were not immunized against NDV with the constructed eukaryotic expression recombinant plasmid. The dose was 100 μg/feather. After 2 weeks, researchers boosted immunization one time. Respectively, collected blood from vein under the wings and separated serum on days 0, 7, 14, 21 and 28 after booster immunization. The blood serum antibody titers of different groups were assayed by indirect ELISA. The results showed that the antibodies producing after immunizing young pigeons with eukaryotic expression plasmid specifically reacted with F protein of PPMV-1. The antibody began to produce on day 7 after immunization were maximum on day 14 and then the level began to decline. This indicated that F protein had good immunogenicity. All young pigeons were challenged with 100 times 50% Egg Infections Dose (EID50) of virus homologous to F gene on day 28 after immunization with eukaryotic expression recombinant plasmid. The results showed that the protective rate of immunized with recombinant plasmid group and immunized with pigeon NDV propolis inactivated vaccine group were respectively, 3.3 and 100% significantly higher than physiological saline group and PCDNA3.1V5HIS mock-vehicle group. The protective rate of pigeon NDV propolis inactivated vaccine group was also higher than the recombinant plasmid group. This indicated that the eukaryotic expressing plasmid of F gene constructed by us as candidated genetic vaccines could induce young pigeons to produce protective immune response but it also needed other methods to raise the efficiency of immunity.
FenYi He, JiongJie He, HuiLin Guo, Ming Yang, ZhiHua Chen and SiJiu Yu, 2012. The Cloning F Gene of Pigeon Paramyxovirus TypeI (PPMV-1) PL Strain and the Study on DNA Vaccine. Journal of Animal and Veterinary Advances, 11: 4210-4216.