A DNA vaccine encoding the FMDV capsid precursor polypeptide P1 and the enhancing effect of bovine herpesvirus 1 VP22 protein as molecular adjuvant.

Abstract

UNLABELLED: DNA vaccines containing the capsid precursor polypeptide P1 gene of foot-and-mouth disease virus (FMDV) alone or combined with the VP22 gene of bovine herpesvirus 1 (BVP22) as molecular adjuvant were constructed and used for immunization of BALB/c mice. The latter were challenged with FMDV and their humoral as well as cell-mediated immune responses and virus clearance capacity were assayed. Both DNA vaccines elicited specific immune responses, however, the DNA vaccine with the BVP22 adjuvant showed stronger responses and more efficient virus clearance. A stronger Th1 response was indicated by the IgG2a/IgG1 ratio. These results indicate that (i) a DNA vaccine based on FMDV P1 can stimulate significant immune responses and virus clearance and (ii) BVP22 is a potentially useful molecular adjuvant for such a vaccine. KEYWORDS: DNA vaccine; foot-and-mouth disease virus; bovine herpesvirus 1.