Sindbis virus replicase-based DNA vaccine construct encoding FMDV-specific multivalent epitope gene: studies on its immune responses in guinea pigs.
Foot-and-mouth disease (FMD) is still a perennial global menace affecting livestock health and production. It is imperative to figure out new ways to curb this disease. In this study, a sindbis virus replicase-based DNA vaccine, pSinCMV-Vac-MEG990, encoding a multivalent epitope gene (representing tandemly linked VP1 C-terminal halves of three foot-and-mouth disease virus (FMDV) serotypes) was constructed. In vitro transfection studies in BHK-21 cells revealed that the construct was able to express FMDV-specific antigen but does not overproduce the antigen. Immunization of guinea pigs with the construct at dose rate of 10, 5, 2 and 1 μg per animal through intramuscular route showed significant neutralizing antibody induction at all doses against all serotype tested as compared to non-immunized controls. On viral challenge of guinea pigs 4 week post-immunization with 1000 GPID(50) of FMDV serotype A, it was observed that the immunization not only delayed the appearance and reduced the severity of FMD lesions significantly (P < 0.05) but also provided complete protection in several guinea pigs. In fact, two of six and one of six guinea pigs were completely protected in 10 and 5 μg immunized groups, respectively. These results suggest that the development of the replicase-based DNA vaccine may provide a promising approach as an alternative vaccine strategy for controlling FMD.
FMD Research Centre, Indian Veterinary Research Institute, Bengaluru, Karnataka, India.
P A
PA
Dar
K
K
Ganesh
G
G
Nagarajan
S
S
Sarika
G R
GR
Reddy
V V S
VV
Suryanarayana
D000818:Animals; D057134:Antibodies, Neutralizing / Q000096:biosynthesis; D000914:Antibodies, Viral / Q000096:biosynthesis / Q000276:immunology*; D002460:Cell Line; D006224:Cricetinae; D004274:DNA, Recombinant / Q000235:genetics / Q000276:immunology; D004259:DNA-Directed DNA Polymerase / Q000235:genetics / Q000276:immunology; D000939:Epitopes / Q000276:immunology; D005260:Female; D005536:Foot-and-Mouth Disease / Q000276:immunology / Q000473:pathology / Q000517:prevention & control*; D029544:Foot-and-Mouth Disease Virus / Q000276:immunology*; D005822:Genetic Vectors / Q000276:immunology; D006168:Guinea Pigs; D007273:Injections, Intramuscular; D008297:Male; D012845:Sindbis Virus / Q000235:genetics*; D014611:Vaccination; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D014764:Viral Proteins / Q000235:genetics / Q000276:immunology*; D014765:Viral Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*
D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D004274:DNA, Recombinant; D000939:Epitopes; D019444:Vaccines, DNA; D014764:Viral Proteins; D014765:Viral Vaccines; C023140:DNA replicase; D004259:DNA-Directed DNA Polymerase