Immunization with a bovine herpesvirus 1 glycoprotein B DNA vaccine induces cytotoxic T-lymphocyte responses in mice and cattle.
Virus-specific cytotoxic T lymphocytes (CTLs) are considered to be important in protection against and recovery from viral infections. In this study, several approaches to induce cytotoxicity against bovine herpesvirus 1 (BHV-1) were evaluated. Vaccination of C57BL/6 mice with BHV-1 induced a strong humoral, but no CTL, response, which may be due to downregulation of major histocompatibility complex class I molecules. In contrast, vaccinia virus expressing glycoprotein B (gB) elicited a weaker antibody response, but strong cytotoxicity, in mice. As an approach to inducing both strong humoral and cellular immune responses, a plasmid vector was then used to express gB. Both antibody and CTL responses were induced by the plasmid encoding gB in C57BL/6 and C3H mice, regardless of the type of vector backbone. This demonstrated that DNA immunization induces a broad-based immune response to BHV-1 gB. Interestingly, removal of the membrane anchor, which resulted in secretion of gB from transfected cells, did not result in reduced cytotoxicity. Here, it is shown that, compared with the cell-associated counterpart, plasmid-encoded secreted protein may induce enhanced immune responses in cattle. Therefore, calves were immunized intradermally with pMASIAtgB, a plasmid encoding the secreted form of gB (tgB), using a needle-free injection system. This demonstrated that pMASIAtgB elicited both humoral responses and activated gamma interferon-secreting CD8+ CTLs, suggesting that a DNA vaccine expressing tgB induces a CTL response in the natural host of BHV-1.
Huang
Y
Y
Vaccine and Infectious Disease Organization, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan, Canada S7N 5E3.
Babiuk
L A
LA
Vaccine and Infectious Disease Organization, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan, Canada S7N 5E3.
van Drunen Littel-van den Hurk
S
S
Vaccine and Infectious Disease Organization, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan, Canada S7N 5E3.
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology / Q000517:prevention & control*; D006566:Herpesviridae Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary; D007242:Herpesvirus 1, Bovine / Q000276:immunology*; D022283:Herpesvirus Vaccines / Q000008:administration & dosage* / Q000276:immunology; D007114:Immunization / Q000662:veterinary; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D010957:Plasmids; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D019444:Vaccines, DNA / Q000008:administration & dosage* / Q000276:immunology; D014764:Viral Proteins / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*
D000914:Antibodies, Viral; D022283:Herpesvirus Vaccines; D019444:Vaccines, DNA; D014764:Viral Proteins; C046998:bovine herpesvirus type-1 glycoproteins