DNA immunization against very virulent infectious bursal disease virus with VP2-4-3 gene and chicken IL-6 gene.
The present study was to investigate the feasibility and efficiency of the DNA vaccine to protect chickens against very virulent infectious bursal disease virus (vvIBDV) infection. A plasmid DNA carrying VP2-4-3 genes of vvIBDV SH95 and a plasmid DNA carrying chicken interleukin-6 (ChIL-6) genes were constructed and designated as pALTER-MAX-VP2-4-3 and pALTER-MAX-ChIL-6 respectively. Several DNA vaccination experiments were performed: 1-week-old chickens were intramuscularly injected with only plasmid pcDNA3-VP2, pALTER-MAX-VP2-4-3 or mixture with pALTER-MAX-ChIL-6. The chickens at 4 weeks old were orally inoculated with vvIBDV SH95. The results showed that immunization with the mixture of pALTER-MAX-VP2-4-3 and pALTER-MAX-ChIL-6 three times conferred protection for 90% of chickens. Enzyme-linked immunosorbent assay (ELISA) antibody titres in chickens immunized together with pALTER-MAX-ChIL-6 were higher than those immunized simply with plasmid pcDNA3-VP2 or pALTER-MAX-VP2-4-3. IBDV was not detected in the bursa of the protected chickens at 8 days after challenge by RT-PCR. The results indicate that protection against vvIBDV can be achieved by using the VP2-4-3 gene of vvIBDV as a DNA vaccine. Furthermore, the simultaneous injection of ChIL-6 plasmid significantly increased the protection after challenge with the very virulent strain.
Sun
J H
JH
The Institute of Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, 2678 Qi Xin Road, Shanghai 201101, China.
Yan
Y X
YX
Jiang
J
J
Lu
P
P
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D018175:Birnaviridae Infections / Q000517:prevention & control / Q000662:veterinary*; D002645:Chickens / Q000235:genetics; D007243:Infectious bursal disease virus / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity; D015850:Interleukin-6 / Q000235:genetics; D011201:Poultry Diseases / Q000517:prevention & control*; D013047:Specific Pathogen-Free Organisms; D014611:Vaccination / Q000662:veterinary; D019444:Vaccines, DNA; D015678:Viral Structural Proteins / Q000235:genetics; D014765:Viral Vaccines
D000914:Antibodies, Viral; D015850:Interleukin-6; C082513:VP2 protein, infectious bursal disease virus; C478244:VP3 protein, infectious bursal disease virus; C478245:VP4 protein, infectious bursal disease virus; D019444:Vaccines, DNA; D015678:Viral Structural Proteins; D014765:Viral Vaccines