Comparative studies of the capsid precursor polypeptide P1 and the capsid protein VP1 cDNA vectors for DNA vaccination against foot-and-mouth disease virus.
BACKGROUND
Foot-and-mouth disease virus (FMDV) causes a severe livestock disease, and the virus is an interesting target for virology and vaccine studies.


METHODS
Here we evaluated comparatively three different viral antigen-encoding DNA sequences, delivered via two physical means (i.e., gene gun delivery into skin and electroporation delivery into muscle), for naked DNA-mediated vaccination in a mouse system.


RESULTS
Both methods gave similar results, demonstrating commonality of the observed DNA vaccine effects. Immunization with a cDNA vector expressing the major viral antigen (VP1) alone routinely failed to induce the production of anti-VP1 or neutralizing antibodies in test mice. As a second approach, the plasmid L-VP1 that produces a transgenic membrane-anchored VP1 protein elicited a strong antibody response, but all test mice failed in the FMDV challenge experiment. In contrast, for mice immunized with the viral capsid precursor protein (P1) cDNA expression vector, both neutralizing antibodies and 80-100% protection in test mice were detected.


CONCLUSIONS
This strategy of using the whole capsid precursor protein P1 cDNA for vaccination, intentionally without the use of virus-specific protease or other encoding genes for safety reasons, may thus be employed as a relevant experimental system for induction or upgrading of effective neutralizing antibody response, and as a convenient surrogate test system for DNA vaccination studies of FMDV and presumably other viral diseases.
Yang
Ning-Sun
NS
Institute of BioAgricultural Sciences, Academia Sinica, Taipei, 11529, Taiwan, ROC. nsyang@gate.sinica.edu.tw
Wang
Jeng-Hwan
JH
Lin
Ku-Feng
KF
Wang
Chien-Yu
CY
Kim
Suk-Am
SA
Yang
Yu-Ling
YL
Jong
Ming-Hwa
MH
Kuo
Tsun-Yung
TY
Lai
Shiow-Suey
SS
Cheng
R Holland
RH
Chan
Ming-Tsair
MT
Liang
Shu-Mei
SM
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D019470:Biolistics; D002213:Capsid / Q000276:immunology; D036022:Capsid Proteins / Q000235:genetics / Q000276:immunology*; D002460:Cell Line; D006224:Cricetinae; D018076:DNA, Complementary; D018274:Electroporation; D029544:Foot-and-Mouth Disease Virus / Q000145:classification / Q000276:immunology*; D005822:Genetic Vectors; D007668:Kidney / Q000166:cytology / Q000196:embryology; D051379:Mice; D008807:Mice, Inbred BALB C; D009500:Neutralization Tests; D011498:Protein Precursors / Q000235:genetics; D011994:Recombinant Proteins / Q000276:immunology; D012703:Serotyping; D013997:Time Factors; D014162:Transfection; D014611:Vaccination; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology*
D000914:Antibodies, Viral; D036022:Capsid Proteins; D018076:DNA, Complementary; D011498:Protein Precursors; D011994:Recombinant Proteins; C442501:VP1 protein, Foot-and-mouth disease virus; D019444:Vaccines, DNA