A prime-boost vaccination strategy using naked DNA followed by recombinant porcine adenovirus protects pigs from classical swine fever.
Weaned pigs (6-week-old) and 7-day-old pre-weaned piglets were vaccinated with naked plasmid DNA expressing the gp55/E2 gene from classical swine fever virus (CSFV). Both groups of pigs were then given a booster dose of recombinant porcine adenovirus expressing the gp55 gene (rPAV-gp55). Following challenge with CSFV, 100% of weaned pigs and 75% pre-weaned piglets were protected from disease. Weaned pigs given a single dose of rPAV-gp55 were also protected, but showed a slight increase in temperature immediately post-challenge. However, weaned animals given a DNA prime before rPAV-gp55 showed no fluctuation in body temperature following challenge and no pathology in spleen or lymph nodes upon post-mortem. In addition, no CSFV could be re-isolated from the rPAV vaccinated group and from only one pig in the prime-boost group following challenge, suggesting that both vaccination regimes have the potential to reduce or prevent virus shedding following experimental challenge.
Hammond
J M
JM
CSIRO, Australian Animal Health Laboratory, Geelong, 3220 Vic., Australia.
Jansen
E S
ES
Morrissy
C J
CJ
Goff
W V
WV
Meehan
G C
GC
Williamson
M M
MM
Lenghaus
C
C
Sproat
K W
KW
Andrew
M E
ME
Coupar
B E
BE
Johnson
M A
MA
D000256:Adenoviridae; D000818:Animals; D001831:Body Temperature; D006691:Classical Swine Fever / Q000517:prevention & control*; D004274:DNA, Recombinant / Q000008:administration & dosage; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D013552:Swine; D014611:Vaccination / Q000662:veterinary*; D019444:Vaccines, DNA; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology; D014886:Weaning
D004274:DNA, Recombinant; D019444:Vaccines, DNA; D014759:Viral Envelope Proteins; C087086:glycoprotein E2, classical swine fever virus